10-K

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

WASHINGTON, DC 20549

FORM 10-K

(Mark One)

☒ ANNUAL REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934

For the fiscal year ended December 31, 2023

OR

☐ TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934

For the transition period from ________________ to ___________________

Commission File Number	Registrant; State of Incorporation; Address; and Telephone Number	IRS Employer Identification No.
001-01245	WISCONSIN ELECTRIC POWER COMPANY	39-0476280

(A Wisconsin Corporation)

231 West Michigan Street

P.O. Box 2046

Milwaukee, WI 53201

(414) 221-2345

Securities registered pursuant to Section 12(b) of the Act:

None

Securities registered pursuant to Section 12(g) of the Act:

Serial Preferred Stock, 3.60% Series, $100 Par Value

Six Per Cent. Preferred Stock, $100 Par Value

Indicate by check mark if the Registrant is a well-known seasoned issuer, as defined in Rule 405 of the Securities Act.

Yes ☐    No ☒

Indicate by check mark if the Registrant is not required to file reports pursuant to Section 13 or Section 15(d) of the Act.

Yes ☐    No ☒

Indicate by check mark whether the Registrant (1) has filed all reports required to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during the preceding 12 months (or for such shorter period that the Registrant was required to file such reports), and (2) has been subject to such filing requirements for the past 90 days.

Yes ☒    No ☐

Indicate by check mark whether the registrant has submitted electronically every Interactive Data File required to be submitted pursuant to Rule 405 of Regulation S-T (§232.405 of this chapter) during the preceding 12 months (or for such shorter period that the registrant was required to submit such files).

Yes ☒    No ☐

Indicate by check mark whether the Registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, a smaller reporting company, or an emerging growth company. See the definitions of "large accelerated filer," "accelerated filer," "smaller reporting company," and "emerging growth company" in Rule 12b-2 of the Exchange Act.

Large accelerated filer	☐	Accelerated filer	☐
Non-accelerated filer	☒	Smaller reporting company		☐
		Emerging growth company		☐

If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act. ☐

Indicate by check mark whether the registrant has filed a report on and attestation to its management’s assessment of

the effectiveness of its internal control over financial reporting under Section 404(b) of the Sarbanes-Oxley Act (15 U.S.C.

7262(b)) by the registered public accounting firm that prepared or issued its audit report. ☐

If securities are registered pursuant to Section 12(b) of the Act, indicate by check mark whether the financial statements of the registrant included in the filing reflect the correction of an error to previously issued financial statements.     ☐

Indicate by check mark whether any of those error corrections are restatements that required a recovery analysis of incentive-based compensation received by any of the registrant's executive officers during the relevant recovery period pursuant to §240.10D-1(b).  ☐

Indicate by check mark whether the Registrant is a shell company (as defined in Rule 12b-2 of the Exchange Act).

Yes ☐    No ☒

As of June 30, 2023 (and currently), all of the common stock of Wisconsin Electric Power Company is held by WEC Energy Group, Inc.

State the aggregate market value of the voting and non-voting common equity held by non-affiliates of the Registrant.

None.

Number of shares outstanding of each class of common stock, as of

January 31, 2024

Common Stock, $10 par value, 33,289,327 shares outstanding

Documents incorporated by reference:

Portions of Wisconsin Electric Power Company's Definitive Information Statement on Schedule 14C for its Annual Meeting of Shareholders, to be held on April 26, 2024, are incorporated by reference into Part III hereof.

WISCONSIN ELECTRIC POWER COMPANY

ANNUAL REPORT ON FORM 10-K

For the Year Ended December 31, 2023

TABLE OF CONTENTS

					Page
CAUTIONARY STATEMENT REGARDING FORWARD-LOOKING INFORMATION					1
PART I					3
ITEM 1.	BUSINESS				3
	A.	INTRODUCTION			3
	B.	UTILITY SEGMENT			3
	C.	REGULATION			12
	D.	ENVIRONMENTAL COMPLIANCE			14
	E.	HUMAN CAPITAL			14
ITEM 1A.	RISK FACTORS				16
ITEM 1B.	UNRESOLVED STAFF COMMENTS				28
ITEM 1C.	CYBERSECURITY				28
ITEM 2.	PROPERTIES				30
ITEM 3.	LEGAL PROCEEDINGS				31
ITEM 4.	MINE SAFETY DISCLOSURES				31
	INFORMATION ABOUT OUR EXECUTIVE OFFICERS				32
PART II					33
ITEM 5.	MARKET FOR REGISTRANT'S COMMON EQUITY, RELATED STOCKHOLDER MATTERS AND ISSUER PURCHASES OF EQUITY SECURITIES				33
ITEM 6.	RESERVED				33
ITEM 7.	MANAGEMENT'S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND RESULTS OF OPERATIONS				34
ITEM 7A.	QUANTITATIVE AND QUALITATIVE DISCLOSURES ABOUT MARKET RISK				53
ITEM 8.	FINANCIAL STATEMENTS AND SUPPLEMENTARY DATA				54
	A.	Report of Independent Registered Public Accounting Firm			54
	B.	Consolidated Income Statements			56
	C.	Consolidated Balance Sheets			57
	D.	Consolidated Statements of Cash Flows			58
	E.	Consolidated Statements of Equity			59
	F.	Notes to Consolidated Financial Statements			60
		Note 1	Summary of Significant Accounting Policies	60
		Note 2	Acquisitions	68
		Note 3	Disposition	68
		Note 4	Related Parties	69
		Note 5	Operating Revenues	71
		Note 6	Credit Losses	72
		Note 7	Regulatory Assets and Liabilities	73
		Note 8	Property, Plant, and Equipment	75
		Note 9	Jointly Owned Utility Facilities	76
		Note 10	Asset Retirement Obligations	77
		Note 11	Common Equity	77
		Note 12	Preferred Stock	79
		Note 13	Short-Term Debt and Lines of Credit	79
		Note 14	Long-Term Debt	80
		Note 15	Leases	81
		Note 16	Income Taxes	85
		Note 17	Fair Value Measurements	87
		Note 18	Derivative Instruments	88
		Note 19	Employee Benefits	88

2023 Form 10-K i Wisconsin Electric Power Company

		Note 20	Segment Information	93
		Note 21	Variable Interest Entities	93
		Note 22	Commitments and Contingencies	94
		Note 23	Supplemental Cash Flow Information	100
		Note 24	Regulatory Environment	100
		Note 25	Other Income, Net	103
		Note 26	New Accounting Pronouncements	103
ITEM 9.	CHANGES IN AND DISAGREEMENTS WITH ACCOUNTANTS ON ACCOUNTING AND FINANCIAL DISCLOSURE				104
ITEM 9A.	CONTROLS AND PROCEDURES				104
ITEM 9B.	OTHER INFORMATION				104
ITEM 9C.	DISCLOSURE REGARDING FOREIGN JURISDICTIONS THAT PREVENT INSPECTIONS				104
PART III					105
ITEM 10.	DIRECTORS, EXECUTIVE OFFICERS AND CORPORATE GOVERNANCE OF THE REGISTRANT				105
ITEM 11.	EXECUTIVE COMPENSATION				105
ITEM 12.	SECURITY OWNERSHIP OF CERTAIN BENEFICIAL OWNERS AND MANAGEMENT AND RELATED STOCKHOLDER MATTERS				105
ITEM 13.	CERTAIN RELATIONSHIPS AND RELATED TRANSACTIONS, AND DIRECTOR INDEPENDENCE				105
ITEM 14.	PRINCIPAL ACCOUNTING FEES AND SERVICES				105
PART IV					106
ITEM 15.	EXHIBITS AND FINANCIAL STATEMENT SCHEDULES				106
ITEM 16.	FORM 10-K SUMMARY				109
SCHEDULE II — VALUATION AND QUALIFYING ACCOUNTS					110
SIGNATURES					111

2023 Form 10-K ii Wisconsin Electric Power Company

GLOSSARY OF TERMS AND ABBREVIATIONS

The abbreviations and terms set forth below are used throughout this report and have the meanings assigned to them below:

Subsidiaries and Affiliates
ATC	American Transmission Company LLC
Bluewater	Bluewater Natural Gas Holding, LLC
UMERC	Upper Michigan Energy Resources Corporation
WBS	WEC Business Services LLC
WE	Wisconsin Electric Power Company
We Power	W.E. Power, LLC
WEC Energy Group	WEC Energy Group, Inc.
WEPCo Environmental Trust	WEPCo Environmental Trust Finance I, LLC
WG	Wisconsin Gas LLC
WPS	Wisconsin Public Service Corporation
Federal and State Regulatory Agencies
Army Corps	United States Army Corps of Engineers
CBP	United States Customs and Border Protection Agency
DOC	United States Department of Commerce
EPA	United States Environmental Protection Agency
FERC	Federal Energy Regulatory Commission
IRS	United States Internal Revenue Service
PSCW	Public Service Commission of Wisconsin
SEC	Securities and Exchange Commission
WDNR	Wisconsin Department of Natural Resources
Accounting Terms
AFUDC	Allowance for Funds Used During Construction
ARO	Asset Retirement Obligation
ASC	Accounting Standards Codification
ASU	Accounting Standards Update
CWIP	Construction Work in Progress
FASB	Financial Accounting Standards Board
GAAP	Generally Accepted Accounting Principles
OPEB	Other Postretirement Employee Benefits
VIE	Variable Interest Entity
Environmental Terms
Act 141	2005 Wisconsin Act 141
BATW	Bottom Ash Transport Water
BTA	Best Technology Available
CASAC	Clean Air Scientific Advisory Committee
CCR	Coal Combustion Residual
CO2	Carbon Dioxide
CWA	Clean Water Act
ELG	Steam Electric Effluent Limitation Guidelines
FGD	Flue Gas Desulfurization
GHG	Greenhouse Gas
LDC	Local Natural Gas Distribution Company
MATS	Mercury and Air Toxics Standards
NAAQS	National Ambient Air Quality Standards
NOx	Nitrogen Oxide
NSPS	New Source Performance Standards
PM	Particulate Matter
SO2	Sulfur Dioxide
WOTUS	Waters of the United States

2023 Form 10-K iii Wisconsin Electric Power Company

WPDES	Wisconsin Pollutant Discharge Elimination System
ZLD	Zero Liquid Discharge
Measurements
Bcf	Billion Cubic Feet
Dth	Dekatherm
lb/MMBtu	Pound Per Million British Thermal Unit
MW	Megawatt
MWh	Megawatt-hour
µg/m3	Micrograms Per Cubic Meter
Other Terms and Abbreviations
AIA	Affiliated Interest Agreement
AMI	Advanced Metering Infrastructure
AOC	Audit and Oversight Committee of the Board of Directors of WEC Energy Group, Inc.
ARR	Auction Revenue Right
Badger Hollow II	Badger Hollow Solar Park II
Blue Sky	Blue Sky Green Field Wind Park
CAO	Chief Administrative Officer
CEO	Chief Executive Officer
CFR	Code of Federal Regulations
Chicago, IL-IN-WI	Chicago, Illinois, Indiana, and Wisconsin
Compensation Committee	Compensation Committee of the Board of Directors of WEC Energy Group, Inc.
CSIRT	Cybersecurity Incident Response Team
Darien	Darien Solar Park
DER	Distributed Energy Resource
DRER	Dedicated Renewable Energy Resource
Enterprise Security Director	Director of Enterprise Security & Compliance
ERGS	Elm Road Generating Station
ER 1	Elm Road Generating Station Unit 1
ER 2	Elm Road Generating Station Unit 2
ERSC	Enterprise Risk Steering Committee
ESG Progress Plan	WEC Energy Group's Capital Investment Plan for Efficiency, Sustainability, and Growth for 2024-2028
ETB	Environmental Trust Bond
EV	Electric Vehicle
Exchange Act	Securities Exchange Act of 1934, as amended
Executive Order 13990	Executive Order 13990 of January 20, 2021 - Protecting Public Health and the Environment and Restoring Science To Tackle the Climate Crisis
FTR	Financial Transmission Right
GCRM	Gas Cost Recovery Mechanism
Glacier Hills	Glacier Hills Wind Park
High Noon	High Noon Solar Energy Center
IRA	Inflation Reduction Act
IT/OT	Information Technology and Operational Technology
ITC	Investment Tax Credit
Koshkonong	Koshkonong Solar Park
LIBOR	London Interbank Offered Rate
LMP	Locational Marginal Price
LNG	Liquefied Natural Gas
MISO	Midcontinent Independent System Operator, Inc.
MISO Energy Markets	MISO Energy and Operating Reserves Market
Montfort	Montfort Wind Energy Center
NYMEX	New York Mercantile Exchange
OCPP	Oak Creek Power Plant
Omnibus Stock Incentive Plan	WEC Energy Group Omnibus Stock Incentive Plan, Amended and Restated, Effective as of May 6, 2021

2023 Form 10-K iv Wisconsin Electric Power Company

Paris	Paris Solar-Battery Park
PHMSA	Pipeline and Hazardous Materials Safety Administration
PIPP	Presque Isle Power Plant
Point Beach	Point Beach Nuclear Power Plant
PPA	Power Purchase Agreement
PSB	Public Service Building
PTC	Production Tax Credit
PWGS	Port Washington Generating Station
PWGS 1	Port Washington Generating Station Unit 1
PWGS 2	Port Washington Generating Station Unit 2
RICE	Reciprocating Internal Combustion Engine
RNG	Renewable Natural Gas
ROE	Return on Equity
RTO	Regional Transmission Organization
S&P	Standard & Poor's
SIP	State Implementation Plan
SSR	System Support Resource
Supreme Court	United States Supreme Court
Tax Legislation	Tax Cuts and Jobs Act of 2017
UFLPA	Uyghur Forced Labor Prevention Act
VAPP	Valley Power Plant
West Riverside	West Riverside Energy Center
Whitewater	Whitewater Cogeneration Facility
WRO	Withhold Release Order
WUA	Wisconsin Utilities Association

2023 Form 10-K v Wisconsin Electric Power Company

CAUTIONARY STATEMENT REGARDING FORWARD-LOOKING INFORMATION

In this report, we make statements concerning our expectations, beliefs, plans, objectives, goals, strategies, and future events or performance. These statements are "forward-looking statements" within the meaning of Section 27A of the Securities Act of 1933, as amended, and Section 21E of the Exchange Act. Readers are cautioned not to place undue reliance on these forward-looking statements. Forward-looking statements may be identified by reference to a future period or periods or by the use of terms such as "anticipates," "believes," "could," "estimates," "expects," "forecasts," "goals," "guidance," "intends," "may," "objectives," "plans," "possible," "potential," "projects," "seeks," "should," "targets," "will," or variations of these terms.

Forward-looking statements include, among other things, statements concerning management's expectations and projections regarding earnings, completion of capital projects, sales and customer growth, rate actions and related filings with regulatory authorities, environmental and other regulations, including associated compliance costs, legal proceedings, effective tax rates, pension and OPEB plans, fuel costs, sources of electric energy supply, coal and natural gas deliveries, remediation costs, climate-related matters, the ESG Progress Plan, liquidity and capital resources, and other matters.

Forward-looking statements are subject to a number of risks and uncertainties that could cause our actual results to differ materially from those expressed or implied in the statements. These risks and uncertainties include those described in Item 1A. Risk Factors and those identified below:

•Factors affecting utility operations such as catastrophic weather-related damage, environmental incidents, unplanned facility outages and repairs and maintenance, and electric transmission or natural gas pipeline system constraints;

•Factors affecting the demand for electricity and natural gas, including political or regulatory developments, varying, adverse, or unusually severe weather conditions, including those caused by climate change, changes in economic conditions, customer growth and declines, commodity prices, energy conservation efforts, and continued adoption of distributed generation by customers;

•The timing, resolution, and impact of rate cases and negotiations, including recovery of deferred and current costs and the ability to earn a reasonable return on investment, and other regulatory decisions impacting our regulated operations;

•The impact of federal, state, and local legislative and/or regulatory changes, including changes in rate-setting policies or procedures, the results of recent rate orders, deregulation and restructuring of the electric and/or natural gas utility industries, transmission or distribution system operation, the approval process for new construction, reliability standards, pipeline integrity and safety standards, allocation of energy assistance, energy efficiency mandates, electrification initiatives and other efforts to reduce the use of natural gas, and tax laws, including those that affect our ability to use PTCs and ITCs, as well as changes in the interpretation and/or enforcement of any laws or regulations by regulatory agencies;

•Federal, state, and local legislative and regulatory changes relating to the environment, including climate change and other environmental regulations impacting generation facilities and renewable energy standards, the enforcement of these laws and regulations, changes in the interpretation of regulations or permit conditions by regulatory agencies, and the recovery of associated remediation and compliance costs;

•The ability to obtain and retain customers, including wholesale customers, due to increased competition in our electric and natural gas markets from retail choice and alternative electric suppliers, and continued industry consolidation;

•The timely completion of capital projects within budgets and the ability to recover the related costs through rates;

•The impact of changing expectations and demands of our customers, regulators, investors, and other stakeholders, including focus on environmental, social, and governance concerns;

•The risk of delays and shortages, and increased costs of equipment, materials, or other resources that are critical to our business operations and corporate strategy, as a result of supply chain disruptions (including disruptions from rail congestion), inflation, and other factors;

•The impact of public health crises, including epidemics and pandemics, on our business functions, financial condition, liquidity, and results of operations;

2023 Form 10-K 1 Wisconsin Electric Power Company

•Factors affecting the implementation of WEC Energy Group's CO2 emission and/or methane emission reduction goals and opportunities and actions related to those goals, including related regulatory decisions, the cost of materials, supplies, and labor, technology advances, the feasibility of competing generation projects, and the ability to execute WEC Energy Group's capital plan;

•The financial and operational feasibility of taking more aggressive action to further reduce GHG emissions in order to limit future global temperature increases;

•The risks associated with inflation and changing commodity prices, including natural gas and electricity;

•The availability and cost of sources of natural gas and other fossil fuels, purchased power, materials needed to operate environmental controls at our electric generating facilities, or water supply due to high demand, shortages, transportation problems, nonperformance by electric energy or natural gas suppliers under existing power purchase or natural gas supply contracts, or other developments;

•Any impacts on the global economy, including from sanctions and impacts on supply chains and fuel prices, generally, from ongoing, expanding, or escalating regional conflicts, including those in Ukraine, Israel, and parts of the Middle East;

•Changes in credit ratings, interest rates, and our ability to access the capital markets, caused by volatility in the global credit markets, our capitalization structure, and market perceptions of the utility industry or us;

•Costs and effects of litigation, administrative proceedings, investigations, settlements, claims, and inquiries;

•The direct or indirect effect on our business resulting from terrorist or other physical attacks and cybersecurity intrusions, as well as the threat of such incidents, including the failure to maintain the security of personally identifiable information, the associated costs to protect our utility assets, technology systems, and personal information, and the costs to notify affected persons to mitigate their information security concerns and to comply with state notification laws;

•The risk of financial loss, including increases in bad debt expense, associated with the inability of our customers, counterparties, and affiliates to meet their obligations;

•Changes in the creditworthiness of the counterparties with whom we have contractual arrangements, including participants in the energy trading markets and fuel suppliers and transporters;

•The investment performance of our employee benefit plan assets, as well as unanticipated changes in related actuarial assumptions, which could impact future funding requirements;

•Factors affecting the employee workforce, including loss of key personnel, internal restructuring, work stoppages, and collective bargaining agreements and negotiations with union employees;

•Advances in technology, and related legislation or regulation supporting the use of that technology, that result in competitive disadvantages and create the potential for impairment of existing assets;

•The risk associated with the value of long-lived assets, including intangible assets, and their possible impairment;

•Potential business strategies to acquire and dispose of assets, which cannot be assured to be completed timely or within budgets;

•The timing and outcome of any audits, disputes, and other proceedings related to taxes;

•The effect of accounting pronouncements issued periodically by standard-setting bodies; and

•Other considerations disclosed elsewhere herein and in other reports we file with the SEC or in other publicly disseminated written documents.

Except as may be required by law, we expressly disclaim any obligation to publicly update or revise any forward-looking statements, whether as a result of new information, future events, or otherwise.

2023 Form 10-K 2 Wisconsin Electric Power Company

PART I

ITEM 1. BUSINESS

A. INTRODUCTION

In this report, when we refer to "us," "we," "our," or "ours," we are referring to Wisconsin Electric Power Company. The term "utility" refers to our regulated activities, while the term "non-utility" refers to our activities that are not regulated. References to "Notes" are to the Notes to Consolidated Financial Statements included in this Annual Report on Form 10-K.

We are a subsidiary of WEC Energy Group and were incorporated in the state of Wisconsin in 1896. We maintain our principal executive offices in Milwaukee, Wisconsin and serve customers in Wisconsin. We conduct our business primarily through our utility reportable segment.

For more information about our utility operations, including financial and geographic information, see Note 20, Segment Information, and Item 7. Management's Discussion and Analysis of Financial Condition and Results of Operations – Results of Operations. For information about our business strategy, see Item 7. Management's Discussion and Analysis of Financial Condition and Results of Operations – Corporate Developments.

Available Information

Our annual reports on Form 10-K, quarterly reports on Form 10-Q, current reports on Form 8-K, and any amendments to those reports are made available on WEC Energy Group's website, www.wecenergygroup.com, free of charge, as soon as reasonably practicable after they are filed with or furnished to the SEC. The SEC maintains an Internet site that contains reports, proxy and information statements, and other information regarding issuers that file electronically with the SEC at www.sec.gov.

B. UTILITY SEGMENT

Electric Utility Operations

We generate and distribute electric energy to customers located in southeastern Wisconsin (including the metropolitan Milwaukee area), east central Wisconsin, and northern Wisconsin.

Operating Revenues

For information about our operating revenues disaggregated by customer class for the years ended December 31, 2023, 2022, and 2021, see Note 1(d), Operating Revenues, and Note 5, Operating Revenues.

Electric Sales

Our electric energy deliveries included supply and distribution sales to retail, wholesale, and resale customers. In 2023, retail revenues accounted for 93.1% of total electric operating revenues, wholesale revenues accounted for 1.2% of total electric operating revenues, and resale revenues accounted for 4.9% of total electric operating revenues. See Item 7. Management's Discussion and Analysis of Financial Condition and Results of Operations – Results of Operations – Utility Segment Contribution to Net Income Attributed to Common Shareholder for information on MWh sales by customer class.

We are authorized to provide retail electric service in designated territories in the state of Wisconsin, as established by indeterminate permits and boundary agreements with other utilities.

We provide wholesale electric service to various customers, including electric cooperatives, municipal joint action agencies, other investor-owned utilities, municipal utilities, and energy marketers.

The majority of our sales for resale are sold into an energy market operated by MISO at market rates based on the availability of our generation and market demand. Retail fuel costs are reduced by the amount that revenue exceeds the costs of sales derived from these opportunity sales.

2023 Form 10-K 3 Wisconsin Electric Power Company

We buy and sell electric power by participating in the MISO Energy Markets. The cost of our individual generation offered into the MISO Energy Markets compared to our competitors affects how often our generating units are dispatched and whether we buy or sell power. For more information on the MISO Energy Markets, see C. Regulation.

Steam Sales

We have a steam utility that generates, distributes, and sells steam supplied by the VAPP to customers in metropolitan Milwaukee, Wisconsin. Steam is used by customers for processing, space heating, domestic hot water, and humidification. Annual sales of steam fluctuate from year to year based on system growth and variations in weather conditions.

Electric Sales Forecast

Our service territory experienced slightly lower weather-normalized retail electric sales in 2023, compared with 2022, due to lower sales to large commercial & industrial customers. We currently forecast retail electric sales volumes to remain relatively flat for 2024, assuming normal weather.

Customers

	Year Ended December 31
(in thousands)	2023	2022	2021
Electric customers – end of year
Residential	1,044.9	1,032.6	1,025.7
Small commercial and industrial	119.3	117.6	116.8
Large commercial and industrial	0.6	0.6	0.6
Wholesale and other	1.6	1.6	1.6
Total electric customers – end of year	1,166.4	1,152.4	1,144.7
Steam customers – end of year	0.4	0.4	0.4

Electric Commercial and Industrial Retail Customers

We provide electric utility service to a diversified base of customers in industries such as metals and other manufacturing, governmental, health services, real estate, and food products.

Electric Generation and Supply Mix

Our electric supply strategy is to provide our customers with energy from a diverse generation portfolio that is expected to balance a stable, reliable, and affordable supply of electricity with environmental stewardship. Through our participation in the MISO Energy Markets, we supply a significant amount of electricity to our customers from generation that we own or lease from We Power. We supplement our internally generated power supply with long-term PPAs, including the Point Beach PPA discussed under the heading "Power Purchase Commitments," and through spot purchases in the MISO Energy Markets. We also sell excess power supply into the MISO Energy Markets when it is economical, which reduces net fuel costs by offsetting costs of purchased power. All options, including owned generation resources and purchased power opportunities, are continually evaluated on a real time basis to select and dispatch the lowest-cost resources available to meet system load requirements.

2023 Form 10-K 4 Wisconsin Electric Power Company

The table below indicates our sources of electric energy supply as a percentage of sales for the three years ended December 31, as well as estimates for 2024:

	Estimate (1)		Actual
	2024		2023		2022		2021
Company-owned or leased generation units:
Coal	25.7	%	30.6	%	29.0	%	36.2	%
Natural gas:
Combined cycle	32.2	%	28.4	%	26.8	%	23.4	%
Steam turbine	1.1	%	1.2	%	1.5	%	1.1	%
Natural gas/oil peaking units	2.8	%	3.5	%	1.7	%	1.1	%
Renewables (2)	5.7	%	4.0	%	4.7	%	3.9	%
Total company-owned or leased generation units	67.5	%	67.7	%	63.7	%	65.7	%
Power purchase contracts:
Nuclear	29.8	%	30.0	%	30.3	%	28.9	%
Natural gas	—	%	—	%	3.3	%	2.9	%
Renewables (2)	0.9	%	0.8	%	0.7	%	0.8	%
Other	—	%	0.2	%	0.3	%	—	%
Total power purchase contracts	30.7	%	31.0	%	34.6	%	32.6	%
Purchased power from MISO	1.8	%	1.3	%	1.7	%	1.7	%
Total purchased power	32.5	%	32.3	%	36.3	%	34.3	%
Total electric utility supply	100.0	%	100.0	%	100.0	%	100.0	%

(1)    The values included in the estimate assume a natural gas price based on the December 2023 NYMEX.

(2)    Includes hydroelectric, biomass, solar, and wind generation.

Electric Generation Facilities

Our generation portfolio is a mix of energy resources having different operating characteristics and fuel sources designed to balance providing energy that is stable, reliable, and affordable with environmental stewardship. We own or lease 5,466 MWs of generation capacity. Our facilities include natural gas-fired plants, coal-fired plants, and renewable generation. Certain of our natural gas-fired generation units have the ability to burn oil if natural gas is not available due to delivery constraints. For more information about our facilities, see Item 2. Properties.

Generation from Leased W.E. Power, LLC Units

We supply electricity to our customers from power plants that we lease from We Power. These plants include the ERGS units and the PWGS units. Lease payments are billed from We Power to us and then recovered in our rates as authorized by the PSCW and the FERC. We operate the We Power units and are authorized by the PSCW and state law to fully recover prudently incurred operating and maintenance costs in our electric rates. As the operator of the units, we may request We Power to make capital improvements to, or further investments in, the units. Under the lease terms, these capital improvements or further investments will increase lease payments paid by us and should ultimately be recovered in our rates.

Environmental Goals

WEC Energy Group has announced goals to achieve reductions in carbon emissions from its electric generation fleet, which includes us, by 60% by the end of 2025 and by 80% by the end of 2030, both from a 2005 baseline. As of the end of 2023, WEC Energy Group's electric generation fleet has achieved a 54% reduction in carbon emissions from the 2005 baseline. WEC Energy Group expects to achieve these goals by continuing to make operating refinements, retiring less efficient generating units, and executing its capital plan. Over the longer term, the target for WEC Energy Group's generation fleet is to be net carbon neutral by 2050.

As part of our path toward these goals, we have started implementing co-firing with natural gas at the ERGS coal-fired units. By the end of 2030, WEC Energy Group expects to use coal as a backup fuel only and believes it will be in a position to eliminate coal as an energy source by the end of 2032.

2023 Form 10-K 5 Wisconsin Electric Power Company

Creating a Sustainable Future

WEC Energy Group's ESG Progress Plan includes the retirement of older, fossil-fueled generation, to be replaced with zero-carbon-emitting renewables and clean natural gas-fired generation. The retirements will contribute to meeting WEC Energy Group's and our goals to reduce CO2 emissions from our electric generation. When taken together, the retirements and new investments in renewables and clean generation discussed in more detail below, should better balance our supply with our demand, while maintaining reliable, affordable energy for our customers.

WEC Energy Group has already retired more than 1,900 MWs of coal-fired generation since the beginning of 2018, which included the 2019 retirement of the PIPP as well as the 2018 retirement of the Pleasant Prairie power plant. See Note 7, Regulatory Assets and Liabilities, for more information related to these power plant retirements. WEC Energy Group expects to retire approximately 1,800 MWs of additional fossil-fueled generation by the end of 2031, which includes the planned retirement in 2024-2025 of OCPP Units 5-8. See Note 8, Property, Plant, and Equipment, for more information.

See Item 7. Management's Discussion and Analysis of Financial Condition and Results of Operations – Corporate Developments for more information on the ESG Progress Plan.

Also see Item 1A. Risk Factors - Risks Related to Legislation and Regulation - Our operations, capital expenditures, and financial results may be affected by the impact of GHG legislation, regulation, and emission reduction goals.

Renewable Generation

We meet a portion of our electric generation supply with various renewable energy resources, including wind, solar, hydroelectric, and biomass. This helps us work towards our goals of reducing carbon emissions while also maintaining compliance with renewable energy legislation. These renewable energy resources also help us maintain diversity in our generation portfolio, which effectively serves as a price hedge against future fuel costs, and will help mitigate the risk of potential unknown costs associated with any future carbon restrictions for electric generators.

In December 2018, we received approval from the PSCW for the DRER pilot program, a program designed to allow large commercial and industrial customers to access renewable resources that we would operate. The DRER pilot is intended to help these larger customers meet their sustainability and renewable energy goals and could add up to 35 MWs of renewables to our portfolio. In addition, in July 2023, the PSCW approved the Renewable Pathway Pilot, which allows our commercial and industrial customers to subscribe to a portion of a utility-scale, Wisconsin-based renewable energy generating facility for up to 125 MWs.

Solar and Battery Storage

In December 2023, the construction of Badger Hollow II located in Iowa County, Wisconsin was completed, and the facility became commercially operational. We own Badger Hollow II together with an unaffiliated utility. Our ownership of this facility is 100 MW.

As part of our commitment to invest in additional zero-carbon generation, in February 2024, we, along with WPS and an unaffiliated utility, filed a request with the PSCW for approval to acquire and construct High Noon. High Noon is a utility-scale solar-powered electric generating facility. The project will be located in Columbia County, Wisconsin and once fully constructed, we will own 225 MWs of solar generation of this project. The construction is expected to be completed by the end of 2026.

We have also received approvals from the PSCW to invest in 680 MWs of additional projects currently in construction, including the following:

•In April 2023, we, along with WPS and an unaffiliated utility, received PSCW approval to acquire Koshkonong, a utility-scale solar-powered electric generating facility. The project will be located in Dane County, Wisconsin and once fully constructed, we will own 225 MWs of solar generation of this project. The construction is expected to be completed in 2026.

•In December 2022, we, along with WPS and an unaffiliated utility, received PSCW approval to acquire and construct Darien, a utility-scale solar-powered electric generating facility. The project will be located in Rock and Walworth counties, Wisconsin and once fully constructed, we will own 188 MWs of solar generation of this project. The construction is expected to be completed in 2024.

2023 Form 10-K 6 Wisconsin Electric Power Company

•In January 2022, we, along with WPS and an unaffiliated utility, received PSCW approval to acquire and construct Paris, a utility-scale solar-powered electric generating facility with a battery energy storage system. The project will be located in Kenosha County, Wisconsin and once fully constructed, we will own 150 MWs of solar generation and 82 MWs of battery storage of this project. The construction of the solar portion and battery storage is expected to be completed in 2024 and 2025, respectively.

•In December 2018, we received approval from the PSCW for the Solar Now pilot program, which is expected to add a total of 35 MWs of solar generation to our portfolio, allowing non-profit and government entities, as well as commercial and industrial customers, to site utility owned solar arrays on their property. Under this program, we have energized 28 Solar Now projects and currently have another one under construction, together totaling more than 30 MWs.

We actively review and pursue distribution system interconnected solar projects. We partner with proven developers to identify and purchase cost effective solar projects for our customers. These projects are typically ground mounted modules in the range of 5-10 MWs and are connected to our distribution system. Currently, we have 30 MWs of distribution connected projects under contract, which are estimated to go in-service in 2024.

Natural Gas-Fired Generation

In July 2023, we, along with WPS, completed construction of seven natural gas-fired generation RICE units at WPS's Weston power plant site. We own 65 MWs of this natural gas-fired generation facility's rated capacity.

In June 2023, we completed the acquisition of 100 MWs of West Riverside's nameplate capacity, in the first of two potential option exercises. West Riverside is a commercially operational dual fueled combined cycle generation facility in Beloit, Wisconsin, and is operated by an unaffiliated utility. In addition, WPS filed a request with the PSCW in September 2023 to exercise a second option to acquire an additional 100 MWs of West Riverside's nameplate capacity. As it did with the first option, in October 2023, WPS filed for approval to assign its ownership interest pursuant to this second option to us, with the transaction expected to close in 2024.

In January 2023, we and WPS completed the acquisition of Whitewater, a commercially operational dual fueled combined cycle generation facility in Whitewater, Wisconsin. We own 121 MWs of Whitewater's rated capacity.

Other Sustainability Programs

In August 2021, the PSCW approved a pilot program for us to install and maintain EV charging equipment for customers at their homes or businesses. The program provides direct benefits to customers by removing cost barriers associated with installing EV equipment. In October 2021, subject to the receipt of any necessary regulatory approvals, WEC Energy Group pledged to expand the EV charging network within the service territories of its electric utilities. In doing so, WEC Energy Group joined a coalition of utility companies in a unified effort to make EV charging convenient and widely available throughout the Midwest. The coalition WEC Energy Group joined is planning to help build and grow EV charging corridors, enabling the general public to safely and efficiently charge their vehicles.

Electric System Reliability

The PSCW requires us to maintain a planning reserve margin above our projected annual peak demand forecast to help ensure reliability of electric service to our customers. These planning reserve requirements are consistent with the MISO calculated planning reserve margin. In 2008, the PSCW established a 14.5% reserve margin requirement for long-term planning (planning years two through ten). For short-term planning (planning year one), the PSCW requires Wisconsin utilities to follow the planning reserve margin established by MISO. MISO implemented seasonal requirements effective June 1, 2023. The installed capacity reserve margins for the planning year June 1, 2024 through May 31, 2025 are as follows: 16.6% summer (June – August); 26.6% fall (September – November); 41.1% winter (December – February); and 39.5% spring (March – May). MISO's short-term reserve margin requirements experience year-to-year and season-to-season fluctuations, primarily due to changes in the generation resource mix and average forced outage rate of generation within the MISO footprint.

We believe that we have adequate capacity through company-owned generation units, leased generating units, and power purchase contracts to meet the MISO calculated planning reserve margin during the current planning year. We also fully anticipate that we will have adequate capacity to meet the planning reserve margin requirements for the upcoming planning year.

2023 Form 10-K 7 Wisconsin Electric Power Company

Fuel and Purchased Power Costs

Our retail electric rates in Wisconsin are established by the PSCW and include base amounts for fuel and purchased power costs. The electric fuel rules set by the PSCW generally allow us to defer, for subsequent rate recovery or refund, under- or over-collections of actual fuel and purchased power costs beyond a 2% price variance from the costs included in the rates charged to customers. For more information about the fuel rules, see C. Regulation.

Our average fuel and purchased power costs per MWh by fuel type, including delivery costs, were as follows for the years ended December 31:

	2023		2022		2021
Coal	$	25.68	$	24.65	$	20.11
Natural gas combined cycle	29.47		41.62		24.35
Natural gas/oil peaking units	68.56		95.89		81.06
Biomass	87.73		78.42		86.24
Purchased power	61.78		59.49		52.84

We purchase coal under long-term contracts, which helps with price stability. Coal and associated transportation services are exposed to volatility in pricing due to changing domestic and world-wide demand for coal and diesel fuel. To mitigate against this volatility risk, we have PSCW approval for a hedging program. This program allows us to hedge, over a 60-month period, up to 75% of our potential risks related to rail transportation fuel surcharge exposure. The results of this hedging program, when used, are reflected in the average costs of fuel and purchased power.

We purchase natural gas for our plants on the spot market from natural gas marketers, utilities, and producers, and we arrange for transportation of the natural gas to our plants. We have firm and interruptible transportation, as well as balancing and storage agreements, intended to support our plants' variable usage. We also have PSCW approval for a hedging program to mitigate against volatility related to natural gas price risk. This program allows us to hedge, over a 60-month period, up to 75% of our estimated natural gas use for electric generation. The results of this hedging program are reflected in the average costs of natural gas.

Coal Supply

We diversify the coal supply for our leased and owned electric generating facilities by purchasing coal from several mines in Wyoming and Pennsylvania, as well as from various other states. For 2024, 100% of our projected coal requirements of 4.7 million tons are contracted under fixed-price contracts. See Note 22, Commitments and Contingencies, for more information on amounts of coal purchases and coal deliveries under contract.

The annual tonnage amounts contracted for the next three years are as follows:

(in thousands)	Annual Tonnage
2024	5,275	(1)
2025	2,500
2026	800

(1)    Coal contracts exceed the total projected requirement due to prior year delivery constraints and forecasted lower operating hours.

Coal Deliveries

All of our coal requirements are expected to be shipped by unit trains that we own or lease under existing transportation agreements. The unit trains transport the coal for electric generating facilities from mines in Wyoming and Pennsylvania. Additional small volume agreements may also be used to supplement the normal coal supply for our facilities. For additional information concerning risks related to coal supply chain disruptions, see the risk factor below.

•Item 1A. Risk Factors – Risks Related to Economic and Market Volatility – We may not be able to obtain an adequate supply of coal, which could limit our ability to operate our coal-fired facilities.

2023 Form 10-K 8 Wisconsin Electric Power Company

Power Purchase Commitments

We enter into short- and long-term power purchase commitments to meet a portion of our anticipated electric energy supply needs. Excluding planning capacity purchases, our power purchase commitments with unaffiliated parties consists of 1,033 MWs per year for 2024 through 2028 related to a long-term PPA for electricity generated by Point Beach. To procure additional planning capacity, we purchase capacity from the MISO annual auction to ensure that we maintain our compliance with planning reserve requirements as established by the PSCW and MISO.

Seasonality

Our electric utility sales are impacted by seasonal factors and varying weather conditions. We sell more electricity during the summer months because of the residential cooling load. We continue to upgrade our electric distribution system, including substations, transformers, and lines, to meet the demand of our customers. In 2023, our generating plants performed as expected during the warmest periods of the summer, and all power purchase commitments under firm contract were received. During this period, we did not make any public appeals for conservation, and we did not interrupt or curtail service to non-firm customers who participate in load management programs. We did have economic interruption events; however, service to customers was not curtailed. Economic interruptions are declared during times in which the price of electricity in the regional market exceeds the cost of operating our peaking generation. During this time, customers taking service under these interruptible programs can choose to continue using electricity at a price based on wholesale market prices or to reduce their load.

Competition

We face competition from various entities and other forms of energy sources available to customers, including self-generation by customers and alternative energy sources. We compete with other utilities for sales to municipalities and cooperatives as well as with other utilities and marketers for wholesale electric business.

For more information on competition in our service territory, see Item 7. Management's Discussion and Analysis of Financial Condition and Results of Operations – Factors Affecting Results, Liquidity, and Capital Resources – Competitive Markets.

Natural Gas Utility Operations

We are authorized to provide retail natural gas distribution service in designated territories in the state of Wisconsin, as established by indeterminate permits and boundary agreements with other utilities. We operate in three distinct service areas including west and south of the City of Milwaukee, the Appleton area, and areas within Iron and Vilas Counties, Wisconsin.

We provide service to residential and commercial and industrial customers. In addition, we offer natural gas transportation services to our customers that elect to purchase natural gas directly from a third-party supplier. Major industries served include real estate, restaurants, governmental, food products, and metals manufacturing. See Item 7. Management's Discussion and Analysis of Financial Condition and Results of Operations – Results of Operations – Utility Segment Contribution to Net Income Attributed to Common Shareholder for information on natural gas sales volumes by customer class.

Operating Revenues

For information about our operating revenues disaggregated by customer class for the years ended December 31, 2023, 2022, and 2021, see Note 1(d), Operating Revenues, and Note 5, Operating Revenues.

Natural Gas Sales Forecast

Our service territory experienced lower weather-normalized retail natural gas deliveries (excluding natural gas deliveries for electric generation) in 2023 as compared to 2022. We currently forecast retail natural gas delivery volumes to grow 0.7% in 2024, assuming normal weather.

2023 Form 10-K 9 Wisconsin Electric Power Company

Customers

	Year Ended December 31
(in thousands)	2023	2022	2021
Customers – end of year
Residential	468.9	463.7	458.6
Commercial and industrial	41.3	40.5	40.2
Transportation	1.0	1.0	1.0
Total customers	511.2	505.2	499.8

Natural Gas Supply, Pipeline Capacity and Storage

We manage portfolios of natural gas supply contracts, storage services, and pipeline transportation services designed to meet varying customer use patterns. For more information on our natural gas utility supply and transportation contracts, see Note 22, Commitments and Contingencies.

Pipeline Capacity and Storage

The interstate pipelines serving Wisconsin access supply from natural gas producing areas in the Southern and Eastern United States, along with western Canada. We have contracted for long-term firm capacity from a number of these sources. This strategy reflects management's belief that overall supply security is enhanced by geographic diversification of the supply portfolio.

Due to variations in natural gas usage in Wisconsin, we have also contracted for substantial underground storage capacity, primarily in Michigan. We have entered into a long-term service agreement for natural gas storage with a wholly owned subsidiary of Bluewater. Bluewater, a wholly owned subsidiary of WEC Energy Group, owns natural gas storage facilities in Michigan and provides approximately one-third of our current storage needs. We target storage inventory levels at approximately 40% of forecasted demand for November through March. Diversity of natural gas supply enables us to manage significant changes in demand and to optimize our overall natural gas supply and capacity costs. We generally inject natural gas into storage during the spring and summer months and withdraw it in the winter months.

We hold daily transportation and storage capacity entitlements with interstate pipeline companies as well as other service providers under varied-length long-term contracts.

Natural gas pipeline capacity and storage and natural gas supplies under contract can be resold in secondary markets. Peak or near-peak demand generally occurs only a few times each year. The secondary markets facilitate utilization of capacity and supply during times when the contracted capacity and supply are in excess of utility demand. The proceeds from these transactions are passed through to customers, subject to our approved GCRM. For information on our GCRM, see Note 1(d), Operating Revenues.

To ensure a reliable supply of natural gas during peak winter conditions, we have LNG and propane facilities located within our distribution system. These facilities are typically utilized during extreme demand conditions to ensure reliable supply to our customers. We recently finished construction of an LNG facility that was placed into service in November 2023, which provides approximately one Bcf of natural gas supply. The use of LNG allows us to meet anticipated peak demand without requiring the construction of additional interstate pipeline capacity.

Combined with our storage capability, management believes that the volume of natural gas under contract is sufficient to meet our forecasted firm peak-day and seasonal demand. Our forecasted design peak-day throughput is 11.4 million therms for the 2023 through 2024 heating season. Our peak daily send-out during 2023 was 6.2 million therms on January 31, 2023.

Natural Gas Supply

Our natural gas supply requirements are met through a combination of fixed-price purchases, index-priced purchases, storage, peak-shaving facilities, and natural gas supply call options. We contract for fixed-term firm natural gas supply each year to meet the demand of firm system sales customers. To supplement natural gas supply and manage risk, we purchase additional natural gas supply on the monthly and daily spot markets.

2023 Form 10-K 10 Wisconsin Electric Power Company

Hedging Natural Gas Supply Prices

As part of our hedging programs, we further reduce our supply cost volatility through the use of a mix of financial instruments, such as NYMEX-based natural gas options and futures contracts. We have PSCW approval to hedge up to 60% of planned winter demand and up to 15% of planned summer demand. This approval allows us to pass 100% of the hedging costs (premiums, brokerage fees and losses) and proceeds (gains) to customers through our GCRM.

Seasonality

Since the majority of our customers use natural gas for heating, customer use is sensitive to weather and is generally higher during the winter months. Accordingly, we are subject to some variations in earnings and working capital throughout the year as a result of changes in weather.

Our working capital needs are met by cash generated from operations and debt (both long-term and short-term). The seasonality of natural gas revenues causes the timing of cash collections to be concentrated from January through June. A portion of our winter natural gas supply needs is typically purchased and stored from April through November. Also, planned capital spending on our natural gas distribution facilities is concentrated in April through November. Because of these timing differences, the cash flow from customers is typically supplemented with temporary increases in short-term borrowings (from external sources) during the late summer and fall. Short-term debt is typically reduced over the January through June period.

Competition

We face varying degrees of competition from other entities and other forms of energy available to consumers. Many large commercial and industrial customers have the ability to switch between natural gas and alternative fuels. Electrification initiatives or mandates are being considered or proposed by local and state governments. In addition, all of our customers have the opportunity to choose a natural gas supplier other than us. We offer natural gas transportation services for customers that elect to purchase natural gas directly from a third-party supplier. We continue to earn distribution revenues from these transportation customers for their use of our distribution system to transport natural gas to their facilities. As such, the loss of revenue associated with the cost of natural gas that our transportation customers purchase from third-party suppliers has little impact on our net income, as it is offset by an equal reduction to natural gas costs.

For more information on competition in our service territory, see Item 7. Management's Discussion and Analysis of Financial Condition and Results of Operations – Factors Affecting Results, Liquidity, and Capital Resources – Competitive Markets.

Environmental Goals

WEC Energy Group continues to reduce methane emissions by improving its natural gas distribution system, and has set a target across its natural gas distribution operations to achieve net-zero methane emissions by the end of 2030. WEC Energy Group plans to achieve its net-zero goal through an effort that includes both continuous operational improvements and equipment upgrades, as well as the use of RNG throughout its utility systems. In 2022, we received approval from the PSCW for an RNG pilot associated with our natural gas distribution system.

2023 Form 10-K 11 Wisconsin Electric Power Company

C. REGULATION

In addition to the specific regulations noted below, we are also subject to various other regulations, which primarily consist of regulations, where applicable, of the EPA, the WDNR, and the Army Corps.

Rates

Our retail electric, natural gas, and steam rates are regulated by the PSCW, and the FERC regulates our wholesale electric rates. Decisions by these regulators can significantly impact our liquidity, financial condition, and results of operations. The following table compares our utility operating revenues by regulatory jurisdiction for each of the three years ended December 31:

	2023				2022				2021
(in millions)	Amount		Percent		Amount		Percent		Amount		Percent
Electric
Wisconsin	$	3,338.6	94.0	%	$	3,172.8	91.7	%	$	2,960.9	92.9	%
FERC – Wholesale	214.9		6.0	%	289.0		8.3	%	227.7		7.1	%
Total	3,553.5		100.0	%	3,461.8		100.0	%	3,188.6		100.0	%
Natural Gas – Wisconsin	491.5		100.0	%	608.5		100.0	%	475.9		100.0	%
Total utility operating revenues	$	4,045.0			$	4,070.3			$	3,664.5

Retail Rates

The PSCW has general supervisory and regulatory powers over public utilities in its jurisdiction including, but not limited to, approval of retail utility rates and standards of service, security issuances, mergers, affiliate transactions, location and construction of electric generating units and natural gas facilities, and certain other additions and extensions to utility facilities.

Historically, retail rates approved by the PSCW have been designed to provide utilities the opportunity to generate revenues to recover all prudently-incurred costs, along with a return on investment sufficient to pay interest on debt and provide a reasonable ROE. Rates charged to customers vary according to customer class and rate jurisdiction. We are subject to an earnings sharing mechanism in which a portion of our earnings are required to be refunded to customers if we earn above our authorized ROE. See Note 24, Regulatory Environment, for more information on our earnings sharing mechanism. The table below reflects our approved ROE and capital structure during 2023.

Regulated Retail Rates	Regulatory Commission	Authorized ROE	Average Common Equity Component
Electric, natural gas, and steam	PSCW	9.80%	53.0%

In addition to amounts collected from customers through approved base rates, we have certain recovery mechanisms in place that allow us to recover or refund prudently incurred costs that differ from those approved in base rates.

Embedded within our electric rates is an amount to recover fuel and purchased power costs. The Wisconsin retail fuel rules require us to defer, for subsequent rate recovery or refund, any under-collection or over-collection of fuel and purchased power costs that are outside of our symmetrical fuel cost tolerance, which the PSCW typically sets at plus or minus 2% of our approved fuel and purchased power cost plan. Our deferred fuel and purchased power costs are subject to an excess revenues test. If our ROE in a given year exceeds the ROE authorized by the PSCW, the recovery of under-collected fuel and purchased power costs would be reduced by the amount by which our return exceeds the authorized amount.

Our natural gas utility operates under a GCRM as approved by the PSCW. Generally, the GCRM allows for a dollar-for-dollar recovery of prudently incurred natural gas costs.

See Note 1(d), Operating Revenues, for more information on the significant mechanisms we had in place during 2023 that allowed us to recover or refund changes in prudently incurred costs from rate case-approved amounts.

We file periodic requests with the PSCW for changes in retail rates. Our rate requests are based on forward looking test years, which reflect additions to infrastructure and changes in costs incurred or expected to be incurred. For information on our regulatory

2023 Form 10-K 12 Wisconsin Electric Power Company

proceedings, see Note 24, Regulatory Environment. Orders from the PSCW can be viewed at https://psc.wi.gov/. The material and information contained on this website are not intended to be a part of, nor are they incorporated by reference into, this Annual Report on Form 10-K.

Wholesale Rates

The FERC regulates our wholesale sales of electric energy, capacity, and ancillary services. We have received market-based rate authority from the FERC. Market-based rate authority allows wholesale electric sales to be made in the MISO market and directly to third parties based on the negotiated market value of the transaction. We also make wholesale sales pursuant to cost-based formula rates. Cost-based formula rates provide for recovery of our costs and an approved rate of return. The predetermined formula is initially based on our expenses from the previous year, but is eventually trued up to reflect actual, current-year costs.

Electric Transmission, Capacity, and Energy Markets

In connection with its status as a FERC-approved RTO, MISO operates an energy and ancillary services market and manages the flow of high-voltage electricity across the transmission system in its region. MISO is responsible for monitoring and ensuring equal access to the electric transmission system in its footprint.

In MISO, transmission costs are allocated in accordance with the MISO tariff, which is reviewed and approved by the FERC. Base transmission costs are paid by load-serving entities located in the service territories of each MISO transmission owner. Costs for new regional transmission projects are allocated to load-serving entities throughout the MISO footprint, while the costs for new generation interconnections are allocated to the interconnection customer.

Within MISO, transmission congestion is monetized and included within an LMP that is established through the energy market. The LMP system includes the ability to hedge transmission congestion costs through ARRs and FTRs. ARRs are allocated to market participants by MISO, and FTRs are purchased through auctions. A new allocation and auction was completed for the period of June 1, 2023, through May 31, 2024. The resulting ARR allocation and the secured FTRs are expected to mitigate our transmission congestion risk for that period.

MISO has seasonal zonal resource adequacy requirements to ensure there is sufficient generation capacity to serve load within each zone and the MISO footprint. To meet this requirement, load-serving entities can own generation and demand response resources, acquire generation capacity through MISO's annual capacity auction, or acquire generation capacity through bilateral contracts. The zone in which our load resides, along with the MISO North region as a whole, had sufficient generation capacity resources to meet their respective planning reserve margins for the period between June 1, 2023 and May 31, 2024.

We manage our electric generation portfolio to minimize our exposure within MISO’s annual capacity auction. This includes managing the retirement of existing generation resources and the addition of new generation resources to maintain a diversified portfolio to ensure we do not have a significant short position.

Other Electric Regulations

We are subject to the Federal Power Act and the corresponding regulations developed by certain federal agencies. Among other things, the Federal Power Act makes electric utility industry consolidation more feasible and authorizes the FERC to review proposed mergers and the acquisition of generation facilities. The FERC also oversees the Electric Reliability Organization, which establishes mandatory electric reliability standards and has the authority to levy monetary sanctions for failure to comply with these standards.

We are subject to Act 141 in Wisconsin which contains certain minimum requirements for renewable energy generation.

Other Natural Gas Regulations

Almost all of the natural gas we distribute is transported to our distribution systems by interstate pipelines. The pipelines' transportation and storage services are regulated by the FERC under the Natural Gas Act and the Natural Gas Policy Act of 1978. In addition, the PHMSA and the PSCW are responsible for monitoring and enforcing requirements governing our natural gas safety compliance programs for our pipelines under United States Department of Transportation regulations. These regulations include 49 CFR Part 191 (Transportation of Natural and Other Gas by Pipeline; Annual Reports, Incident Reports, and Safety-Related

2023 Form 10-K 13 Wisconsin Electric Power Company

Condition Reports), 49 CFR Part 192 (Transportation of Natural and Other Gas by Pipeline: Minimum Federal Safety Standards), and 49 CFR Part 195 (Transportation of Hazardous Liquids by Pipeline).

We also continue to monitor the progress of the PHMSA’s proposed rulemaking titled "Gas Pipeline Leak Detection and Repair," which could have a significant impact on us. A final rule is expected to be released in 2024.

We are required to provide natural gas service and grant credit (with applicable deposit requirements) to customers within our service territory. We are generally not allowed to discontinue natural gas service during winter moratorium months to residential heating customers who do not pay their bills. Federal and certain state governments have programs that provide for a limited amount of funding for assistance to our low-income customers.

Compliance Costs

The regulations and oversight described above significantly influence our operating environment, and may cause us to incur compliance and other related costs and may affect our ability to recover these costs from our utility customers. Any anticipated capital expenditures for compliance with government regulations for the next three years are included in the estimated capital expenditures described in Item 7. Management's Discussion and Analysis of Financial Condition and Results of Operations – Liquidity and Capital Resources – Cash Requirements.

D. ENVIRONMENTAL COMPLIANCE

Our operations, especially as they relate to our coal-fired generating facilities, are subject to extensive environmental regulation by state and federal environmental agencies governing air and water quality, hazardous and solid waste management, environmental remediation, and management of natural resources. Costs associated with complying with these requirements are significant. Additional future environmental regulations or revisions to existing laws, including for example, additional regulation related to GHG emissions, coal combustion products, air emissions, water use, or wastewater discharges and other climate change issues, could significantly increase these environmental compliance costs.

Anticipated expenditures for environmental compliance and certain remediation issues for the next three years are included in the estimated capital expenditures described in Item 7. Management's Discussion and Analysis of Financial Condition and Results of Operations – Liquidity and Capital Resources – Cash Requirements. For a discussion of certain environmental matters affecting us, including rules and regulations relating to air quality, water quality, land quality, and climate change, see Note 22, Commitments and Contingencies.

E. HUMAN CAPITAL

We believe our employees are among our most important resources, so investing in human capital is critical to our success. We strive to foster a diverse workforce and inclusive workplace; attract, retain and develop talented personnel; and keep our employees safe and healthy.

WEC Energy Group's Board of Directors retains collective responsibility for comprehensive risk oversight of WEC Energy Group and its subsidiaries, including critical areas that could impact our sustainability, such as human capital. Management regularly reports to WEC Energy Group's Board of Directors on human capital management topics, including corporate culture, diversity, equity, and inclusion, employee development, and safety and health. WEC Energy Group's Board of Directors delegates specified duties to its committees. In addition to its responsibilities relative to executive compensation, the Compensation Committee has oversight responsibility for reviewing organizational matters that could significantly impact us, including succession planning. The Compensation Committee reviews recruiting and development programs and priorities, receives updates on key talent, and assesses workforce diversity across WEC Energy Group and its subsidiaries.

Workforce

As of December 31, 2023, we had 2,533 employees, including 1,955 that are represented under union agreements. We believe we have very good overall relations with our workforce. In order to attract and retain talent, we provide competitive wages and benefits to our employees based on their performance, role, location, and market data. Our compensation package also includes a 401(k)

2023 Form 10-K 14 Wisconsin Electric Power Company

savings plan with an employer match, an annual incentive plan based on meeting company goals, healthcare and insurance benefits, vacation and paid time off days, as well as other benefits.

Diversity, Equity, and Inclusion

We are committed to fostering a diverse workforce and inclusive workplace. Our commitment is a core strategic competency and an integral part of our culture. As of December 31, 2023, women and racial minorities represented approximately 25% and 19%, respectively, of our workforce. WEC Energy Group has a number of initiatives that promote diverse workforce contributions, educate employees about diversity, equity, and inclusion, and ensure its companies, including us, are attractive employers for persons of diverse backgrounds. These initiatives include nine business resource groups (voluntary, employee-led groups organized around a particular shared background or interest), mentoring programs, and training for leaders on countering unconscious bias, building inclusive teams, and preventing workplace harassment. We also support external leadership and educational programs that support, train, and promote women and minorities in the communities we serve.

Safety and Health

WEC Energy Group's Executive Safety Committee directs our safety and health strategy, works to ensure consistency across groups, and reinforces our ongoing safety commitment that we refer to as “Target Zero.” Under our Target Zero commitment, we have an ultimate goal of zero incidents, accidents, and injuries. Our corporate safety program provides a forum for addressing employee concerns, training employees and contractors on current safety standards, and recognizing those who demonstrate a safety focus. We monitor and set goals for days away, restricted or transferred metrics, and measurable leading indicators, which together raise awareness about employee safety and guide injury-prevention activities.

We also provide employees various benefits and resources designed to promote healthy living, both at work and at home. We encourage employees to receive preventive examinations and to proactively care for their health through free health screenings, wellness challenges, and other resources.

Development and Training

Employee training and development of both technical and leadership skills are integral aspects of our human capital strategy. We provide employees with a wide range of development opportunities, including online training, simulations, live classes, and mentoring to assist with their career advancement. These programs include safety and technical job skill training as well as soft-skill programs focused on relevant subjects, including communication and change management. Development of leadership skills remains a top priority and is specialized for all levels of employees. We have specific leadership programs for aspiring leaders and new supervisors, managers, and directors. This development of our employees is an integral part of our succession planning and provides continuity for our senior leadership.

2023 Form 10-K 15 Wisconsin Electric Power Company

ITEM 1A. RISK FACTORS

We are subject to a variety of risks, many of which are beyond our control, that may adversely affect our business, financial condition, and results of operations. You should carefully consider the following risk factors, as well as the other information included in this report and other documents filed by us with the SEC from time to time, when making an investment decision.

Risks Related to Legislation and Regulation

Our business is significantly impacted by governmental regulation and oversight.

We are subject to significant state, local, and federal governmental regulations, including regulations by the PSCW and the FERC. These regulations significantly influence our operating environment, may affect our ability to recover costs from utility customers, affect our ability to implement WEC Energy Group's corporate strategy, and cause us to incur substantial compliance and other costs. Changes in regulations, interpretations of regulations, or the imposition of new regulations could also significantly impact us, including requiring us to change our business operations. Many aspects of our operations are regulated and impacted by government regulation, including, but not limited to: the rates we charge our retail electric, natural gas, and steam customers; our authorized rate of return; construction and operation of electric generating facilities and electric and natural gas distribution systems, including the ability to recover such costs; decommissioning generating facilities, the ability to recover the related costs, and continuing to recover the return on the net book value of these facilities; wholesale power service practices; electric reliability requirements and accounting; participation in the interstate natural gas pipeline capacity market; standards of service; issuance of debt securities; short-term debt obligations; transactions with affiliates; and billing practices. Failure to comply with any applicable rules or regulations may lead to customer refunds, penalties, and other payments, which could materially and adversely affect our results of operations and financial condition.

The rates we are allowed to charge our customers for retail and wholesale services have the most significant impact on our financial condition, results of operations, and liquidity. Rate regulation provides us an opportunity to recover prudently incurred costs and earn a reasonable rate of return on invested capital. However, our ability to obtain rate adjustments in the future is dependent upon regulatory action, the outcome of which can be influenced by the level of opposition by intervening parties; potential rate impacts; increasing levels of regulatory review; and changes in the political, regulatory, or legislative environments. There is no assurance that our regulators will consider all of our costs to have been prudently incurred. In addition, our rate proceedings may not always result in rates that fully recover our costs or provide for a reasonable ROE. We defer certain costs and revenues as regulatory assets and liabilities for future recovery from or refund to customers, as authorized by our regulators. Future recovery of regulatory assets is not assured and is subject to review and approval by our regulators. If recovery of regulatory assets is not approved or is no longer deemed probable, these costs would be recognized in current period expense and could have a material adverse impact on our results of operations, cash flows, and financial condition.

Changes in the local and national political, regulatory, and economic environment have had, and may in the future have, an adverse effect on regulatory decisions, which could impair our ability to recover costs historically collected from customers. These decisions, which may come from any level of government, may cause us to cancel or delay current or planned projects, to reduce or delay other planned capital expenditures, or to pay for investments or otherwise incur costs that we may not be able to recover through rates or otherwise.

We believe we have obtained the necessary permits, approvals, authorizations, certificates, and licenses for our existing operations, have complied in all material respects with all of their associated terms, and that our business is conducted in accordance with applicable laws. These permits, approvals, authorizations, certificates, and licenses may be revoked or modified by the agencies that granted them if facts develop that differ significantly from the facts assumed when they were issued. In addition, permits and other approvals and licenses are often granted for a term that is less than the expected life of the associated facility. Licenses and permits may require periodic renewal, which may result in additional requirements being imposed by the granting agency. In addition, existing regulations may be revised or reinterpreted by federal, state, and local agencies, or these agencies may adopt new laws and regulations that apply to us. We cannot predict the impact on our business and operating results of any such actions by these agencies.

If we are unable to recover costs of complying with regulations or other associated costs in customer rates in a timely manner, or if we are unable to obtain, renew, or comply with these governmental permits, approvals, authorizations, certificates, or licenses, our results of operations and financial condition could be materially and adversely affected.

2023 Form 10-K 16 Wisconsin Electric Power Company

We face significant costs to comply with existing and future environmental laws and regulations.

Our operations are subject to extensive and evolving federal, state, and local environmental laws, regulations, and permit requirements related to, among other things, air emissions (including, but not limited to: CO2, methane, mercury, SO2, and NOx), protection of natural resources, water quality, wastewater discharges, and management of hazardous and toxic substances and solid wastes and soils. The EPA has recently adopted and implemented (or is in the process of implementing) new environmental regulations, with more in the proposal process. These include regulations that govern the emission of NOx, ozone, fine particulates, and other air pollutants under the Clean Air Act through the NAAQS, climate change, NSPS for GHG emissions from new, modified, and reconstructed fossil-fueled power plants, other air quality regulations, and water quality regulations. For example, the EPA finalized regulations under the CWA that govern cooling water intake structures at our power plants, revised again the effluent guidelines for steam electric generating plants, and along with the Army Corps, released a final rule revising the definition of WOTUS that may impact projects requiring federal permits. Several of these rules were challenged or reviewed by agencies under the Biden Administration's Executive Order 13990, which creates additional uncertainty. As a result of these challenges and reviews, existing environmental laws and regulations may be revised or new laws or regulations may be adopted at the federal, state, or local level.

We incur significant capital and operating resources to comply with environmental laws, regulations, and requirements, including costs associated with the installation of pollution control equipment; operating restrictions on our facilities; and environmental monitoring, emissions fees, and permits at our facilities. The operation of emission control equipment and compliance with rules regulating our intake and discharge of water could also increase our operating costs and reduce the generating capacity of our power plants. These regulations may create substantial additional costs in the form of taxes or emission allowances and could affect the availability and/or cost of fossil fuels and our ability to continue operating certain generating units. Failure to comply with these laws, regulations, and requirements, even if caused by factors beyond our control, may result in the assessment of civil or criminal penalties and fines. We continue to assess the potential cost of complying, and to explore different alternatives in order to comply, with these and other environmental regulations.

As a result of these compliance costs and other factors, certain of our coal-fired electric generating facilities have become uneconomical to maintain and operate, which has resulted in these units being retired or converted to an alternative type of fuel. As part of WEC Energy Group's commitment to a cleaner energy future, we have already retired approximately 1,500 MWs of coal-fired generation since the beginning of 2018. WEC Energy Group expects to retire approximately 1,800 MWs of additional fossil-fueled generation by the end of 2031, and plans to replace a portion of the retired capacity by building and owning zero-carbon-emitting renewable generation facilities. We continue to evaluate the conversion of certain coal units to natural gas.

We are also subject to significant liabilities related to the investigation and remediation of environmental impacts at certain of our current and former facilities and at third-party owned sites. We accrue liabilities and defer costs (recorded as regulatory assets) incurred in connection with our former manufactured gas plant sites. These costs include all costs incurred to date that we expect to recover, management's best estimates of future costs for investigation and remediation and related legal expenses, and are net of amounts recovered (or that may be recovered) from insurance or other third parties. Due to the potential for the imposition of stricter standards and greater regulation in the future, the possibility that other potentially responsible parties may not be willing or financially able to contribute to cleanup costs, a change in conditions or the discovery of additional contamination, our remediation costs could increase, and the timing of our capital and/or operating expenditures in the future may accelerate or could vary from the amounts currently accrued.

Litigation over environmental issues and claims of various types, including property damage, personal injury, common law nuisance, and citizen enforcement of environmental laws and regulations, occurs frequently throughout the United States. This litigation has included claims for damages alleged to have been caused by GHG and other emissions and exposure to regulated substances and/or requests for injunctive relief in connection with such matters. In addition to claims relating to our current facilities, we may also be subject to potential liability in connection with the environmental condition of facilities that we previously owned and operated, regardless of whether the liabilities arose before, during, or after the time we owned or operated these facilities. If we fail to comply with environmental laws and regulations or cause (or caused) harm to the environment or persons, that failure or harm may result in the assessment of civil penalties and damages against us. The incurrence of a material environmental liability or a material judgment in any action for personal injury or property damage related to environmental matters could have a material adverse effect on our results of operations and financial condition.

In the event we are not able to recover all of our environmental expenditures and related costs from our customers in the future, our results of operations and financial condition could be adversely affected. Further, increased costs recovered through rates could contribute to reduced demand for electricity and natural gas, which could adversely affect our results of operations, cash flows, and financial condition.

2023 Form 10-K 17 Wisconsin Electric Power Company

Our operations, capital expenditures, and financial results may be affected by the impact of greenhouse gas legislation, regulation, and emission reduction goals.

There is significant attention to issues concerning climate change. Management expects this attention to continue since climate change is one of President Biden's primary initiatives, with significant actions being taken by his administration. As a result, we expect the EPA and states to finalize and implement additional regulations to restrict emissions of GHGs. There have also been increasing efforts to introduce and adopt electrification initiatives and/or mandates and other efforts to reduce or eliminate reliance on natural gas as an energy source. In addition, there is increasing activism from other stakeholders, including institutional investors and other sources of financing, to accelerate the transition to lower GHG emissions.

Costs associated with such legislation, regulation, and emission reduction goals could be significant within our electric and natural gas operations. GHG regulations that may be finalized in the future, at either the federal or state level, may cause our environmental compliance spending to differ materially from the amounts currently estimated. There is no guarantee that we will be allowed to fully recover costs incurred to comply with these and other federal and state regulations or that cost recovery will not be delayed or otherwise conditioned. These regulations, as well as changes in the fuel markets and advances in technology, could make additional electric generating units uneconomic to maintain or operate, may impact how we operate our existing fossil-fueled power plants and biomass facility, and could cause us to retire and replace units earlier than planned under the ESG Progress Plan, which could lead to a possible loss on abandonment and reduced revenues. In addition, our natural gas delivery system may generate fugitive gas as a result of normal operations and as a result of excavation, construction, and repair. Fugitive gas typically vents to the atmosphere and consists primarily of methane. CO2 is also a byproduct of natural gas consumption.

In a movement toward electrification, certain states and municipalities near our service territory have passed legislation or are considering ordinances banning natural gas used in new construction in order to limit GHG emissions. There have also been efforts to restrict residential natural gas-fired appliances. Future local, statewide, or nationwide actions like these to regulate GHG emissions could increase the price of natural gas, reduce the demand for natural gas, cause us to accelerate the replacement and/or updating of our natural gas delivery system, and adversely affect our ability to operate our natural gas facilities. A significant increase in the price of natural gas may increase rates for our natural gas customers, which could also reduce natural gas demand and revenues. The adoption of electrification initiatives and/or mandates could also result in an increase in electrical demand and increased investment costs for existing or new electrical systems. These types of initiatives and/or mandates could result in increased costs associated with permitting and siting of new technologies and delayed installation and start-up timelines. In addition, financial investments in older carbon intensive technologies may not be fully realized.

WEC Energy Group has set goals to achieve reductions in carbon emissions from its electric generation fleet by 60% by the end of 2025 and by 80% by the end of 2030, both from a 2005 baseline. Over the longer term, the target for WEC Energy Group's generation fleet is to be net carbon neutral by 2050. WEC Energy Group also believes it will be in a position to eliminate coal as an energy source by the end of 2032.

We continue to monitor the financial and operational feasibility of taking more aggressive action to further reduce GHG emissions in order to limit future global temperature increases. WEC Energy Group continues to reduce methane emissions by improving its natural gas distribution systems. WEC Energy Group set a target across its natural gas distribution operations to achieve net-zero methane emissions by the end of 2030.

The ability to achieve these reductions in CO2 and methane emissions depends on many external factors, including the ability to make operating refinements, the retirement of less efficient generating units, the development of relevant energy technologies, the use of RNG throughout our natural gas utility systems, and the ability of WEC Energy Group to execute its capital plan. These efforts could impact how we operate our electric generating units and natural gas facilities and lead to increased competition and regulation, all of which could have a material adverse effect on our operations and financial condition.

Changes in tax legislation, IRS audits, or our inability to use certain tax benefits and carryforwards, may adversely affect our financial condition, results of operations, and cash flows, as well as our credit ratings.

Tax legislation and regulations can adversely affect, among other things, our financial condition, results of operations, cash flows, liquidity, and credit ratings. Future changes to corporate tax rates or policies, including under Treasury Regulations and guidance issued in connection with the IRA, could require us to take material charges against earnings. Such changes include, among other things, increasing the federal corporate income tax rate, disallowing or limiting the use of certain tax benefits and carryforwards, limiting interest deductions, and altering the expensing of capital expenditures. Our inability to manage these changes, an adverse

2023 Form 10-K 18 Wisconsin Electric Power Company

determination by one of the applicable taxing jurisdictions, or additional interpretations, implementing regulations, amendments, or technical corrections by the Treasury Department, the IRS, or state income tax authorities, could significantly impact our financial results and cash flows.

We have significantly reduced our federal and state income tax liabilities in the past through tax credits, net operating losses, and charitable contribution deductions. A reduction in or disallowance of these tax benefits could adversely affect our earnings and cash flows. We have not fully used these allowed tax benefits in our previous tax filings and have carried them forward to use against future taxable income. Our inability to generate sufficient taxable income in the future to fully use these tax carryforwards before they expire, or to transfer future tax credits as discussed below, could significantly affect our tax obligations and financial results.

In addition, we have invested, and plan to continue to invest, in renewable energy generating facilities. These facilities generate PTCs or ITCs that we can use to reduce our federal tax obligations. Under the IRA, a transferability option also allows us to sell these tax credits to third parties. This is a new market that may require additional regulations and guidance from taxing authorities. The amount of tax credits we earn depends on available government incentives and policies, the amount of electricity produced, the applicable tax credit rate, or the amount of the investment in qualifying property. In addition, a variety of operating and economic factors, including transmission constraints, adverse weather conditions, and breakdown or failure of equipment, could significantly reduce the PTCs generated by the renewable projects we have invested in, resulting in a material adverse impact on our financial condition and results of operations. The imposition of additional taxes, tariffs, or other assessments related to renewable energy projects or the equipment necessary to generate or deliver it, as well as any reductions or eliminations of tax credits or other governmental incentives that promote renewable energy generating facilities, may limit our ability to make further investments in renewable energy generating facilities or reduce the returns on our existing investments.

We are also uncertain as to how credit rating agencies, capital markets, the FERC, or state public utility commissions will treat any future changes to federal or state tax legislation. These impacts could subject us to credit rating downgrades. In addition, certain financial metrics used by credit rating agencies, such as our funds from operations-to-debt percentage, could be negatively impacted by changes in federal or state income tax legislation.

We could be subject to higher costs and penalties as a result of mandatory reliability standards.

We are subject to mandatory reliability and critical infrastructure protection standards established by the North American Electric Reliability Corporation and enforced by the FERC. The critical infrastructure protection standards focus on controlling access to critical physical and cybersecurity assets. Compliance with the mandatory reliability standards could subject us to higher operating costs. If we are found to be in noncompliance with the mandatory reliability standards, we could be subject to sanctions, including substantial monetary penalties, or damage to our reputation.

Risks Related to the Operation of Our Business

Public health crises, including epidemics and pandemics, could adversely affect our business functions, financial condition, liquidity, and results of operations.

Public health crises, including epidemics and pandemics, and any related government responses may adversely impact the economy and financial markets and could have a variety of adverse impacts on us, including a decrease in revenues; increased bad debt expense; increases in past due accounts receivable balances; and access to the capital markets at unreasonable terms or rates.

Public health crises, including epidemics and pandemics, and any related government responses could also impair our ability to develop, construct, and operate facilities. Risks include extended disruptions to supply chains and inflation, resulting in increased costs for labor, materials, and services, which could adversely impact WEC Energy Group's ability to implement its corporate strategy. We may also be adversely impacted by labor disruptions and productivity as a result of infections, employee attrition, and a reduced ability to replace departing employees as a result of employees who leave or forego employment to avoid any required precautionary measures.

Despite our efforts to manage the impacts of public health crises, including epidemics and pandemics, that may occur in the future, the extent to which they may affect us depends on factors beyond our knowledge or control. As a result, we are unable to determine the potential impact any such public health crises, including epidemics and pandemics, may have on our business plans and operations, liquidity, financial condition, and results of operations.

2023 Form 10-K 19 Wisconsin Electric Power Company

Our operations are subject to risks arising from the reliability of our electric generation, transmission, and distribution facilities, natural gas infrastructure facilities, renewable energy facilities, and other facilities, as well as the reliability of third-party transmission providers.

Our financial performance depends on the successful operation of our electric generation, natural gas and electric distribution facilities, and renewable energy facilities. The operation of these facilities involves many risks, including operator error and the breakdown or failure of equipment or processes.

Potential breakdown or failure may occur due to severe weather (i.e., storms, tornadoes, floods, droughts, etc.); catastrophic events (i.e., fires, earthquakes, and explosions); public health crises, including epidemics and pandemics; significant changes in water levels in waterways; fuel supply or transportation disruptions; accidents; employee labor disputes; construction delays or cost overruns; delays in the replacement of aging infrastructure; shortages of or delays in obtaining equipment, material, and/or labor; performance below expected levels; operating limitations that may be imposed by environmental or other regulatory requirements; terrorist or other physical attacks; or cybersecurity intrusions. Any of these events could lead to substantial financial losses, including increased maintenance costs, and unanticipated capital expenditures. Because our electric generation and renewable energy facilities are interconnected with third-party transmission facilities, the operation of our facilities could also be adversely affected by events impacting their systems. Unplanned outages at our power plants may reduce our revenues, cause us to incur significant costs if we are required to operate our higher cost electric generators or purchase replacement power to satisfy our obligations, and could result in additional maintenance expenses.

Insurance, warranties, performance guarantees, or recovery through the regulatory process may not cover any or all of these lost revenues or increased expenses, which could adversely affect our results of operations and cash flows.

Our natural gas operations depend upon the availability of adequate interstate pipeline transportation capacity and natural gas.

We purchase almost all of our natural gas supply from interstate sources that must be transported to our service territory. Interstate pipeline companies transport the natural gas to our natural gas systems under firm service agreements that are designed to meet the requirements of our core markets. A significant disruption to interstate pipelines capacity or reduction in natural gas supply due to events including, but not limited to, operational failures or disruptions, hurricanes, tornadoes, floods, freeze-off of natural gas wells, terrorist or physical attacks, cyberattacks, other acts of war, or legislative or regulatory actions or requirements, including remediation related to integrity inspections or regulations and laws enacted to address climate change or other environmental matters, could reduce the normal interstate supply of natural gas and thereby significantly disrupt our operations and/or reduce earnings.

Our operations are subject to various conditions that can result in fluctuations in energy sales to customers, including customer growth and general economic conditions in our service area, varying weather conditions, and energy conservation efforts.

Our results of operations and cash flows are affected by the demand for electricity and natural gas, which can vary greatly based upon:

•Fluctuations in customer growth and general economic conditions in our service area. Customer growth and energy use can be negatively impacted by population declines as well as economic factors in our service territory, including workforce reductions, stagnant wage growth, changing levels of support from state and local government for economic development, business closings, and reductions in the level of business investment. Our electric and natural gas operations are impacted by economic cycles and the competitiveness of the commercial and industrial customers we serve. Any economic downturn, disruption of financial markets, or reduced incentives by state government for economic development could adversely affect the financial condition of our customers and demand for their products or services. These risks could directly influence the demand for electricity and natural gas as well as the need for additional power generation and generating facilities. We could also be exposed to greater risks of accounts receivable write-offs if customers are unable to pay their bills.

•Weather conditions. Demand for electricity is greater in the summer and winter months when cooling and heating is necessary. In addition, demand for natural gas peaks in the winter heating season. As a result, our overall results may fluctuate substantially on a seasonal basis. In addition, milder temperatures during the summer cooling season and during the winter heating season may result in lower revenues and net income.

•Our customers' continued focus on energy conservation. Our customers' use of electricity and natural gas has decreased as a result of continued individual conservation efforts, including the use of more energy efficient technologies, and could be further reduced by new building codes, DERs, energy storage technology, and private solar. Customers could also voluntarily reduce their consumption of energy in response to decreases in their disposable income and increases in energy prices. Conservation of

2023 Form 10-K 20 Wisconsin Electric Power Company

energy can be influenced by certain federal and state programs that are intended to influence how consumers use energy. For example, several states, including Wisconsin, have adopted energy efficiency targets to reduce energy consumption.

As part of our planning process, we estimate the impacts of changes in customer growth and general economic conditions, weather, and customer energy conservation efforts, but risks still remain. Any of these matters, as well as any regulatory delay in adjusting rates as a result of reduced sales from effective conservation measures or the adoption of new technologies, could adversely impact our results of operations and financial condition.

Our operations are subject to the effects of global climate change.

A changing climate creates uncertainty and could result in broad changes, both physical and financial in nature, to our service territory. If climate changes occur that result in extreme temperatures in our service territory, our financial results could be adversely impacted by lower electric and natural gas usage and higher natural gas costs. An extreme weather event could result in downed wires and poles or damage to other operating equipment, which could result in us incurring significant restoration costs and foregoing sales of energy and lost revenues. Extreme weather in summer could cause electric load to be interrupted or certain customers to be curtailed who participate in load management programs. Additionally, an extreme weather event could also cause the cost of natural gas purchased for our natural gas utility customers and for the use of fuel at our generation facilities to be temporarily driven significantly higher than our normal winter weather expectations. Although we have a regulatory mechanism in place for recovering all prudently incurred natural gas costs, our regulators could disallow recovery or order the refund of any costs determined to be imprudent.

In addition, our operations could be adversely affected and our facilities placed at greater risk of damage should changes in global climate produce, among other possible conditions, unusual variations in temperature and weather patterns, which could result in more intense, frequent and extreme weather events, such as wind storms including derecho events, floods, tornadoes, snow and ice storms, or abnormal levels of precipitation. Extreme weather may result in unexpected increases in customer load, requiring us to procure additional power at wholesale prices for our retail operations, unpredictable curtailment of customer load by MISO to maintain grid reliability, or other grid reliability issues. Any of these events could lead to substantial financial losses including increased maintenance costs or unanticipated capital expenditures. The cost of storm restoration efforts may also not be fully recoverable through the regulatory process.

Our corporate strategy may be impacted by policy and legal, technology, market, and reputational risks and opportunities that are associated with the transition to lower GHG emissions. In addition, changes in policy to combat climate change, including mitigation and adaptation efforts, and technology advancement, each of which can also accelerate the implications of a transition to lower emissions, may materially adversely impact our results of operations and cash flows through significant capital expenditures and investments in renewable generation.

Our operations and future results may be impacted by changing expectations and demands of our customers, regulators, investors, and other stakeholders, including heightened emphasis on environmental, social, and governance concerns.

Our ability to execute WEC Energy Group's strategy and achieve anticipated financial outcomes are influenced by the expectations of our customers, regulators, investors, and other stakeholders. Those expectations are based in part on the core fundamentals of affordability and reliability but are also increasingly focused on our ability to meet rapidly changing demands for new and varied products, services, and offerings. Additionally, the risks of global climate change continues to shape our customers’ sustainability goals and energy needs, as well as the investment and financing criteria of investors. Failure to meet these increasing expectations or to adequately address the risks and external pressures from regulators, customers, investors, and other stakeholders may impact our reputation and affect our ability to achieve favorable outcomes in future rate cases or our results of operations. Furthermore, the increasing use of social media may accelerate and increase the potential scope of negative publicity we might receive and could increase the negative impact on our reputation, business, results of operations, and financial condition.

As it relates to electric generation, a diversified fleet with increasingly clean generation resources may facilitate more efficient financing and lower costs. Conversely, jurisdictions utilizing more carbon-intensive generation such as coal may experience difficulty attracting certain investors and obtaining the most economical financing terms available. Furthermore, with this heightened emphasis on environmental, social, and governance concerns, and climate change in particular, there is an increased risk of litigation.

2023 Form 10-K 21 Wisconsin Electric Power Company

Our operations and corporate strategy may be adversely affected by supply chain disruptions and inflation.

Our business is dependent on the global supply chain to ensure that equipment, materials, and other resources are available to both expand and maintain services in a safe and reliable manner. Protracted, expanding or escalating regional conflicts, including the conflicts in Ukraine, Israel, and parts of the Middle East, as well as strained relationships between the United States and other countries related to such conflicts, could further contribute to current domestic and global supply chain disruptions that are delaying the delivery, and in some cases resulting in shortages of, materials, equipment, and other resources that are critical to our business operations. Failure to eliminate or manage the constraints in the supply chain may eventually impact the availability of items that are necessary to support normal operations as well as materials that are required to implement our corporate strategy for continued utility and infrastructure growth, including our renewable energy projects.

Moreover, prices of equipment, materials, and other resources have increased as a result of these supply chain disruptions and may continue to increase in the future, as a result of inflation. Increases in inflation raise our costs for labor, materials, and services, and failure to secure these resources on economically acceptable terms, as well as any regulatory delay in adjusting rates to account for increased costs, may adversely impact our financial condition and results of operations.

We are actively involved with multiple significant capital projects, which are subject to a number of risks and uncertainties that could adversely affect project costs and completion of construction projects.

Our business requires substantial capital expenditures for investments in, among other things, capital improvements to our electric generating facilities, electric and natural gas distribution infrastructure, LNG storage, and other projects, including projects for environmental compliance. We also expect to continue constructing and investing in renewable energy generating facilities as part of WEC Energy Group's ESG Progress Plan and its goal to be net carbon neutral by 2050.

Achieving the intended benefits of any large construction project is subject to many uncertainties, some of which we will have limited or no control over, that could adversely affect project costs and completion time. Supply chain disruptions, including solar panel shortages and delays, increasing material costs, government tariffs, and other factors, could impact the timing of completion of our renewable projects. For example, the UFLPA's prohibition on imports of solar panels manufactured with certain silica-based products originating in Xinjiang, China, has delayed the release of solar panels to us for our renewables projects. Additional risks include, but are not limited to, the ability to adhere to established budgets and time frames; the availability of labor or materials at estimated costs; the ability of contractors to perform under their contracts; strikes; adverse weather conditions; potential legal challenges; changes in applicable laws or regulations; rising interest rates; the impact of public health crises, including epidemics and pandemics; other governmental actions; continued public and policymaker support for such projects; and events in the global economy.

Certain of these projects require the approval of the PSCW. If construction of PSCW-approved projects should materially and adversely deviate from the schedules, estimates, and/or projections on which the approval was based, the PSCW may deem the additional capital costs as imprudent and disallow recovery of them through rates, and otherwise available PTCs and ITCs for renewable energy projects could be lost or lose value. In addition, the PSCW, in a future rate proceeding, may alter the timing or amount of certain costs for which recovery is allowed.

We sometimes enter into equipment purchase orders and construction contracts and incur engineering and design service costs in advance of receiving necessary regulatory approvals and/or siting or environmental permits. If any of these projects are canceled for any reason, including failure to receive necessary regulatory approvals and/or siting or environmental permits, significant cancellation penalties under the equipment purchase orders and construction contracts could occur. In addition, if any construction work or investments have been recorded as an asset, an impairment may need to be recorded in the event the project is canceled.

To the extent that delays occur, costs become unrecoverable, tax credits are lost or lose value, or we or third parties with whom we invest and/or partner otherwise become unable to effectively manage and complete capital projects, our results of operations, cash flows, and financial condition may be adversely affected.

Our operations are subject to risks beyond our control, including but not limited to, cybersecurity intrusions, terrorist or other physical attacks, acts of war, or unauthorized access to personally identifiable information.

We have been subject to attempted cyber attacks from time to time, and will likely continue to be subject to such attempted attacks; however, these prior attacks have not had a material impact on our system or business operations. Despite the implementation of security measures, all assets and systems are potentially vulnerable to disability, failures, or unauthorized access

2023 Form 10-K 22 Wisconsin Electric Power Company

due to physical or cybersecurity intrusions caused by human error, vendor bugs, terrorist or other physical attacks (including potential attacks on our substations and other electric distribution equipment), acts of war, or other malicious acts. These threats could result in a full or partial disruption of our ability to generate, transmit, purchase, or distribute electricity or natural gas or cause environmental repercussions. If our assets or systems were to fail, be physically damaged, or be breached, and were not recovered in a timely manner, we may be unable to perform critical business functions, and data, including sensitive information, could be compromised. Cybersecurity attacks, including attacks targeting utility systems and other critical infrastructure may increase during periods of heightened or escalating geopolitical tensions.

We operate in an industry that requires the use of sophisticated information technology systems and network infrastructure, which in turn control an interconnected network of generation, distribution, and transmission systems shared with third parties. A successful physical or cybersecurity intrusion may occur despite our security measures or those we require of our vendors, including compliance with reliability and critical infrastructure protection standards. Successful cybersecurity intrusions, including those targeting the electronic control systems used at our generating facilities and electric and natural gas transmission, distribution, and LNG storage systems, could disrupt our operations and result in loss of service to customers. Attacks may come through ransomware, software updates or patches, or firmware that hackers can manipulate. These intrusions may cause unplanned outages at our power plants, which may reduce our revenues or cause us to incur significant costs if we are required to operate our higher cost electric generators or purchase replacement power to satisfy our obligations, and could result in additional maintenance expenses. The risk of such intrusions may also increase our capital and operating costs as a result of having to implement increased security measures for protection of our information technology and infrastructure.

Our continued efforts to integrate, consolidate, and streamline our operations with those of WEC Energy Group's other subsidiaries have also resulted in increased reliance on current and recently completed projects for technology systems. The failure to enhance existing information technology systems and implement new technology, could adversely affect our operations. We implement procedures to protect our systems, but we cannot guarantee that the procedures we have implemented to protect against unauthorized access to secured data and systems are adequate to safeguard against all security breaches. The failure of any of these or other similarly important technologies, or our inability to support, update, expand, and/or integrate these technologies with those of our affiliates could materially and adversely impact our operations, diminish customer confidence and our reputation, materially increase the costs we incur to protect against these risks, and subject us to possible financial liability or increased regulation or litigation.

Our business requires the collection and retention of personally identifiable information of our customers and employees, who expect that we will adequately protect such information. In some cases, we rely on third-party hosted services to support our business operations. Malicious actors may target these providers to disrupt the services they provide to us, or to use those third parties to attack us. Security breaches of our or our third-party service providers' systems may expose us to a risk of loss or misuse of confidential and proprietary information. A significant theft, loss, or fraudulent use of personally identifiable information may lead to potentially large costs to notify and protect the impacted persons, and/or could cause us to become subject to significant litigation, costs, liability, fines, or penalties, any of which could materially and adversely impact our results of operations as well as our reputation with customers and regulators, among others. In addition, we may be required to incur significant costs associated with governmental actions in response to such intrusions or to strengthen our information and electronic control systems. We may also need to obtain additional insurance coverage related to the threat of such intrusions.

Threats to our systems and operations continue to emerge as new ways to compromise components into our systems or networks are developed. Any operational disruption or environmental repercussions caused by on-going or future threats to our assets and technology systems could result in a significant decrease in our revenues or significant reconstruction or remediation costs, which could materially and adversely affect our results of operations, financial condition, and cash flows. The costs of repairing damage to our facilities, operational disruptions, protecting personally identifiable information, and notifying impacted persons, as well as related legal claims, may also not be recoverable in rates, may exceed the insurance limits on our insurance policies, or, in some cases, may not be covered by insurance.

Advances in technology, and legislation or regulations supporting such technology, could make our electric generating facilities less competitive and may impact the demand for natural gas.

Advances in new technologies that produce or store power or reduce power consumption are ongoing and include renewable energy technologies, customer-oriented generation, energy storage devices, and energy efficiency technologies. We generate power at central station power plants and utility-scale renewable generation facilities to achieve economies of scale and produce power at a competitive cost. Distributed generation technologies that produce power, including fuel cells, microturbines, wind turbines, solar

2023 Form 10-K 23 Wisconsin Electric Power Company

cells, and related energy storage devices, have technologically improved and have become more cost competitive than they were in the past.

Recently enacted legislation, including the IRA and the Infrastructure Investment and Jobs Act, promotes the construction and cost-effectiveness of renewable energy generation, including distributed generation technologies for self-supply of electricity by our customers and third parties. Increased use of technologies such as private solar and battery storage in our service territories could reduce our recovery of fixed costs, could result in customers leaving the electric distribution system, and could cause an increase in customer net energy metering, which allows customers with private solar to receive bill credits for surplus power at the full retail amount. Over time, customer adoption of these technologies could result in us not being able to fully recover the costs and investment in generation. In December 2022, the PSCW issued a declaratory ruling finding that a third-party financed DER is not a “public utility” under Wisconsin law. Although the finding was limited to the specific facts and circumstances of the lease presented in that petition and is being appealed, similar findings or a broader policy position could have a material adverse impact on our business operations.

Federal and state regulations and other efforts designed to promote and expand the use of distributed generation technologies also incentivize modernization of the electric distribution grid to, among other things, accommodate two-way flows of electricity and increase the grid's capacity to interconnect to these distributed generation technologies. Other legislation or regulations could be adopted supporting the use of these technologies at below cost or that permit third-party sales from such facilities, and allow these facilities to interconnect to our distribution system. There is also a risk that advances in technology will continue to reduce the costs of these alternative methods of producing power to a level that is competitive with that of central station and utility-scale renewable power production.

In addition, we cannot predict the effect that development of alternative energy sources or new technology may have on our natural gas operations, including whether subsidies of alternative energy sources by local, state, and federal governments might be expanded, or what impact this might have on the supply of or the demand for natural gas.

If these technologies become cost competitive and achieve economies of scale, our market share could be eroded, and the value of our generating facilities and natural gas distribution systems could be reduced. Advances in technology, or changes in legislation or regulations, could also change the channels through which our customers purchase or use power and natural gas, which could reduce our sales and revenues or increase our expenses.

We transport and distribute natural gas, which involves numerous risks that may result in accidents and other operating risks and costs.

Inherent in natural gas distribution activities are a variety of hazards and operational risks, such as leaks, accidental explosions, and mechanical problems, which could materially and adversely affect our results of operations, financial condition, and cash flows. In addition, these risks could result in serious injury to employees and non-employees, loss of human life, significant damage to property, environmental pollution, impairment of operations, and substantial losses to us. The location of natural gas pipelines near populated areas, including residential areas, commercial business centers, and industrial sites, could increase the level of damages resulting from these risks. These activities may subject us to litigation and/or administrative proceedings from time to time, which could result in substantial monetary judgments, fines, or penalties against us, or be resolved on unfavorable terms. Further, delays in the replacement of aging infrastructure may lead to increased costs and disruptions in operations that could also negatively impact our financial results.

We may fail to attract and retain an appropriately qualified workforce.

We operate in an industry that requires many of our employees to possess unique technical skill sets. Events such as an aging workforce without appropriate replacements, the mismatch of skill sets to future needs, or the unavailability of contract resources may lead to operating challenges or increased costs. These operating challenges include lack of resources, loss of knowledge, and a lengthy time period associated with skill development. Failure to hire and obtain replacement employees, including the ability to transfer significant internal historical knowledge and expertise to the new employees, may adversely affect our ability to manage and operate our business. If we are unable to successfully attract and retain an appropriately qualified workforce, our results of operations could be adversely affected.

2023 Form 10-K 24 Wisconsin Electric Power Company

Our counterparties may fail to meet their obligations, including obligations under power purchase, natural gas supply, natural gas pipeline capacity, and transportation agreements.

We are exposed to the risk that counterparties to various arrangements who owe us money, electricity, natural gas, or other commodities or services will not be able to perform their obligations. Should the counterparties to these arrangements fail to perform or if capacity is inadequate, we may be required to replace the underlying commitment at current market prices or we may be unable to meet all of our customers' electric and natural gas requirements unless or until alternative supply arrangements are put in place. In such event, we may incur losses, and our results of operations, financial position, or liquidity could be adversely affected.

We have entered into several power purchase, natural gas supply, natural gas pipeline capacity, and transportation agreements with non-affiliated companies. Revenues are dependent on the continued performance by the counterparties of their obligations under these agreements. Although we have a comprehensive credit evaluation process and contractual protections, it is possible that one or more counterparties could fail to perform their obligations. If this were to occur, we generally would expect that any operating and other costs that were initially allocated to a defaulting customer's power purchase, natural gas supply, natural gas pipeline capacity, or transportation agreement would be reallocated among our retail customers. To the extent these costs are not allowed to be reallocated by our regulators or there is any regulatory delay in adjusting rates, a counterparty default under these agreements could have a negative impact on our results of operations and cash flows.

Risks Related to Economic and Market Volatility

Our business is dependent on our ability to successfully access capital markets on competitive terms and rates.

We rely on access to credit and capital markets to support our capital requirements, including expenditures for our utility infrastructure and to comply with future regulatory requirements, to the extent not satisfied by the cash flow generated by our operations. We have historically secured funds from a variety of sources, including the issuance of short-term and long-term debt securities. In addition, we rely on a committed bank credit agreement as back-up liquidity, which allows us to access the low cost commercial paper markets. The availability of credit depends upon the ability of banks providing commitments under the facility to provide funds when their obligations to do so arise. Systemic risk of the banking system and the financial markets could prevent a bank from meeting its obligations under the credit agreement.

Successful implementation of our long-term business strategies, including capital investment, is dependent upon our ability to access the capital markets, including the banking and commercial paper markets, on competitive terms and rates. Continued elevation of, or further increases in, interest rates may adversely affect our results of operations and our ability to earn our approved rate of return. High interest rates may also impair our ability to cost-effectively finance capital expenditures and to refinance maturing debt.

Our access to the credit and capital markets could be limited, or our cost of capital significantly increased, due to any of the following risks and uncertainties:

•A rating downgrade;

•Failure to comply with debt covenants;

•An economic downturn or uncertainty;

•Prevailing market conditions and rules;

•Political tensions, including civil unrest and election volatility;

•Concerns over foreign economic conditions;

•Changes in tax policy;

•Changes in investment criteria of institutional investors or banks, including any policies that would limit or restrict funding for companies with fossil fuel-related investments;

•War or the threat of war; and

•The overall health and view of the utility and financial institution industries.

If any of these risks or uncertainties limit our access to the credit and capital markets or significantly increase our cost of capital, it could limit our ability to implement, or increase the costs of implementing, our business plan, which, in turn, could materially and adversely affect our results of operations, cash flows, and financial condition.

2023 Form 10-K 25 Wisconsin Electric Power Company

A downgrade in our credit ratings could negatively affect our ability to access capital at reasonable costs and/or require the posting of collateral.

There are a number of factors that impact our credit ratings, including, but not limited to, capital structure, regulatory environment, the ability to cover liquidity requirements, and other requirements for capital. We could experience a downgrade in ratings if the rating agencies determine that our level of business or financial risk, or that of the utility industry, has deteriorated. Changes in rating methodologies by the rating agencies could also have a negative impact on credit ratings.

Any downgrade by the rating agencies could:

•Increase borrowing costs under our existing credit facility;

•Require the payment of higher interest rates in future financings and possibly reduce the pool of creditors;

•Decrease funding sources by limiting our access to the commercial paper market;

•Limit the availability of adequate credit support for our operations; and

•Trigger collateral requirements in various contracts.

Fluctuating commodity prices could negatively impact our operations.

Our operating and liquidity requirements are impacted by changes in the forward and current market prices of natural gas, coal, electricity, renewable energy credits, and ancillary services.

We burn natural gas in several of our electric generation plants and as a supplemental fuel at several coal-fired plants. In many instances the cost of purchased power is tied to the cost of natural gas. The cost of natural gas may increase because of disruptions in the supply of natural gas due to a curtailment in production or distribution, international market conditions, the demand for natural gas, and the availability of shale gas and potential regulations and/or other government action affecting its accessibility.

For Wisconsin retail electric customers, we bear the risk for the recovery of fuel and purchased power costs within a symmetrical 2% fuel tolerance band compared to the forecast of fuel and purchased power costs established in our rate structure. Prudently incurred fuel and purchased power costs are recovered dollar-for-dollar from our wholesale electric customers. We receive dollar-for-dollar recovery of prudently incurred natural gas costs from our natural gas customers.

Changes in commodity prices could result in:

•Higher working capital requirements, particularly related to natural gas inventory, accounts receivable, and cash collateral postings;

•Reduced profitability to the extent that lower revenues, increased bad debt, and higher interest expense are not recovered through rates;

•Higher rates charged to our customers, which could impact our competitive position;

•Reduced demand for energy, which could impact revenues and operating expenses; and

•Shutting down of generation facilities if the cost of generation exceeds the market price for electricity.

We may not be able to obtain an adequate supply of coal, which could limit our ability to operate our coal-fired facilities.

We own, lease, and operate several coal-fired electric generating units. Although we generally carry sufficient coal inventory at our generating facilities to protect against an interruption or decline in supply, there can be no assurance that the inventory levels will be adequate. While we have coal supply and transportation contracts in place, we cannot assure that the counterparties to these agreements will be able to fulfill their obligations to supply coal to us or that we will be able to take delivery of all the coal volume contracted for. Coal deliveries may occasionally be restricted because of rail congestion and maintenance, derailments, weather, public health crises, including epidemics and pandemics, and supplier financial hardship. Supplier financial hardship is a result of decreased demand for coal due to increased natural gas and renewable energy generation, the impact of environmental regulations, and environmental concerns related to coal-fired generation.

If we are unable to obtain our coal requirements under our coal supply and transportation contracts, we may be required to purchase coal at higher prices or we may be forced to reduce generation at our coal-fired units, which could lead to increased fuel costs. The increase in fuel costs could result in either reduced margins on net sales into the MISO Energy Markets, a reduction in the volume of net sales into the MISO Energy Markets, and/or an increase in net power purchases in the MISO Energy Markets. There is

2023 Form 10-K 26 Wisconsin Electric Power Company

no guarantee that we would be able to fully recover any increased costs in rates or that recovery would not otherwise be delayed, either of which could adversely affect our results of operations and cash flows.

Our use of derivative contracts could result in financial losses.

We use derivative instruments such as swaps, options, futures, and forwards to manage commodity price exposure. We could recognize financial losses as a result of volatility in the market value of these contracts or if a counterparty fails to perform. These risks are managed through risk management policies, which might not work as planned and cannot entirely eliminate the risks associated with these activities. In addition, although our hedging programs must be approved by the PSCW, derivative contracts entered into for hedging purposes might not offset the underlying exposure being hedged as expected, resulting in financial losses. In the absence of actively quoted market prices and pricing information from external sources, the value of these financial instruments can involve management's judgment or use of estimates. Changes in the underlying assumptions or use of alternative valuation methods could affect the reported fair value of these contracts.

Restructuring in the regulated energy industry and competition in the retail and wholesale markets could have a negative impact on our business and revenues.

The regulated energy industry continues to experience significant structural changes. Deregulation or other changes in Wisconsin could allow third-party suppliers to contract directly with customers for their natural gas and electric supply requirements. In addition, legislation or regulation that supports distributed energy technologies or that allows third party sales from such technologies could result in further competition. This increased competition in the retail and wholesale markets could have a material adverse financial impact on us.

The FERC continues to support the existing RTOs that affect the structure of the wholesale market within these RTOs. In connection with its status as a FERC-approved RTO, MISO implemented bid-based energy markets that are part of the MISO Energy Markets. All market participants, including us, must submit day-ahead and/or real time bids and offers for energy at locations across the MISO region. MISO then calculates the most efficient solution for all of the bids and offers made into the market that day and establishes an LMP that reflects the market price for energy. We are required to follow MISO's instructions when dispatching generating units to support MISO's responsibility for maintaining the stability of the transmission system. MISO also implemented an ancillary services market for operating reserves that schedules energy and ancillary services at the same time as part of the energy market, allowing for more efficient use of generation assets in the MISO Energy Markets. These market designs continue to have the potential to increase the costs of transmission, the costs associated with inefficient generation dispatching, the costs of participation in the MISO Energy Markets, and the costs associated with estimated payment settlements.

The FERC rules related to transmission are designed to facilitate competition in the wholesale electricity markets among regulated utilities, non-utility generators, wholesale power marketers, and brokers by providing greater flexibility and more choices to wholesale customers, including initiatives designed to encourage the integration of renewable sources of supply. In addition, along with transactions contemplating physical delivery of energy, financial laws and regulations impact hedging and trading based on futures contracts and derivatives that are traded on various commodities exchanges, as well as over-the-counter. Technology changes in the power and fuel industries also have significant impacts on wholesale transactions and related costs. We currently cannot predict the impact of these and other developments or the effect of changes in levels of wholesale supply and demand, which are driven by factors beyond our control.

Volatility in the securities markets, interest rates, changes in assumptions, market conditions, and other factors may impact the performance of our benefit plan holdings and other investment funds.

We have significant obligations related to pension and OPEB plans. If WEC Energy Group is unable to successfully manage our benefit plan assets and medical costs, our cash flows, financial condition, or results of operations could be adversely impacted. Our cost of providing these plans is dependent upon a number of factors, including actual plan experience, changes made to the plans, and assumptions concerning the future. Types of assumptions include earnings on plan assets, discount rates, the level of interest rates used to measure the required minimum funding levels of the plans, future government regulation, estimated withdrawals by retirees, and our required or voluntary contributions to the plans. Plan assets are subject to market fluctuations and may yield returns that fall below projected return rates. In addition, medical costs for both active and retired employees may increase at a rate that is significantly higher than we currently anticipate. Our funding requirements could be impacted by a decline in the market value of plan assets, changes in interest rates, changes in demographics (including the number of retirements), or changes in life expectancy assumptions.

2023 Form 10-K 27 Wisconsin Electric Power Company

General Risks

We may be unable to obtain insurance on acceptable terms or at all, and the insurance coverage we do obtain may not provide protection against all significant losses.

Our ability to obtain insurance, as well as the cost and coverage of such insurance, could be affected by developments affecting our business; international, national, state, or local events; and the financial condition of insurers and our contractors that are required to acquire and maintain insurance for our benefit. Insurance coverage may not continue to be available at all or at rates or terms similar to those presently available to us. In addition, our insurance may not be sufficient or effective under all circumstances and against all hazards or liabilities to which we may be subject. Any losses for which we are not fully insured or that are not covered by insurance at all could materially adversely affect our results of operations, cash flows, and financial position.

ITEM 1B. UNRESOLVED STAFF COMMENTS

None.

ITEM 1C. CYBERSECURITY

As a wholly-owned subsidiary of WEC Energy Group, our cybersecurity-related risks are managed by WEC Energy Group's cybersecurity risk management program.

WEC Energy Group's Board of Directors is responsible for general oversight of the risk environment and associated management policies and practices of WEC Energy Group and its subsidiaries, including us. The WEC Energy Group Board of Directors has delegated to its AOC the responsibility for oversight of our major risk categories and exposures, including with respect to cybersecurity, and management's processes to monitor and control them. The AOC meets regularly throughout the year and receives and reviews various risk management reports about IT/OT cybersecurity, data security, and physical security risk management reports, and discusses these matters with appropriate management and other personnel. WEC Energy Group's CEO (who also serves as our CEO) and its CAO regularly report to the AOC and the WEC Energy Group Board of Directors about cybersecurity matters and risks as well as the adequacy and effectiveness of the cybersecurity risk management program.

To foster an enterprise-wide approach to risk management, WEC Energy Group has established an ERSC chaired by its CEO and comprised of a cross-functional group of senior leaders from across WEC Energy Group's organization. The ERSC regularly reviews key risk areas and oversees the development and implementation of effective compliance and risk management practices, including the use of internal and external audits. WEC Energy Group's Board of Directors and the AOC receive reports regarding the same. Governance of WEC Energy Group's cybersecurity risk management program is overseen by the ERSC, along with steering committees for information security, operational technology security, third-party vendor security controls, Sarbanes-Oxley security controls, and North American Electric Reliability Corporation Critical Infrastructure Protection compliance.

WEC Energy Group's CAO is responsible for enterprise-wide information technology services and cybersecurity system strategy. In this capacity, the CAO oversees the cybersecurity risk management program, which is maintained and implemented by the Enterprise Security Director. WEC Energy Group's CAO has 24 years of experience at the company, during which time she has held a number of management and leadership positions, including Chief Information Officer, through which she has developed expertise in WEC Energy Group's IT/OT cybersecurity, data security, and physical security environment and risk profile.

The Enterprise Security Director, in collaboration with her team, is responsible for IT/OT cybersecurity, data security, and physical security. The Enterprise Security Director identifies, evaluates, and facilitates mitigation of cyber, data, and physical security risks and reports on cybersecurity matters and risks to the ERSC and the AOC. The Enterprise Security Director has over 26 years of experience in IT/OT cybersecurity, data security and physical security, and is a certified information system security professional. She is also a member of numerous state and national cybersecurity organizations.

Cybersecurity Risk Management Program

Our cybersecurity-related risks are managed through monitoring, defense and response tools, audits and assessments of the program’s effectiveness, industry collaboration, and employee training and awareness. WEC Energy Group's cybersecurity risk management program utilizes the cybersecurity framework and maturity models from the National Institute of Standards and Technology and the United States Department of Energy to continually assess its maturity. This includes regular internal security

2023 Form 10-K 28 Wisconsin Electric Power Company

audits and vulnerability assessments, as well as regular engagement with third-party security experts for external assessments of WEC Energy Group's security controls, including technical, physical, and social aspects. To better comprehend the scope and magnitude of any active threats to our industry and nation and their potential impact on our IT/OT systems, we communicate with other utility companies, government agencies, and other sectors of the economy concerning cybersecurity incidents. All employees are required to complete training annually regarding information security and acceptable use of corporate electronic resources. Annual role-based cybersecurity training as well as ongoing participation in a corporate phishing campaign program, is also required of employees and contractors. In addition, as part of the cybersecurity program, WEC Energy Group has established controls and procedures to assess the adequacy of controls in place at third-party vendors to protect corporate information, including restricted and confidential restricted information we provide to third-party vendors, their employees, or authorized agents. These third-party vendors are also subject to a background investigation prior to being granted physical or electronic access to the company's private property, or physical access to customer premises on behalf of the company.

As part of the cybersecurity program, WEC Energy Group has adopted a cybersecurity incident response plan (the “Plan”) designed to identify, evaluate, respond to, and resolve cybersecurity incidents impacting IT/OT systems. Pursuant to the terms of the Plan, WEC Energy Group has established a CSIRT Steering Committee which includes, among others, WEC Energy Group's Chief Financial Officer (who also serves as our Chief Financial Officer), CAO, and the Enterprise Security Director. The CSIRT Steering Committee is responsible for overseeing and implementing the Plan in the event of a cybersecurity threat or incident and provides updates regarding the status of the response to senior management, including WEC Energy Group's CEO, who provide updates and reports regarding cybersecurity incidents to the AOC and/or the WEC Energy Group Board of Directors at regularly scheduled meetings or more frequently, as needed.

In response to an identified cybersecurity incident, or as it deems appropriate, the CSIRT Steering Committee will assemble and oversee a CSIRT, comprised of appropriate personnel and subject matter experts depending on the scope and severity of the incident, relevant or impacted business units and entities, and type of information or systems potentially compromised by the cybersecurity incident. When assembled, the CSIRT is responsible for developing and implementing an overall response strategy to contain, control, and remediate the cybersecurity incident, including securing affected systems and/or information, mitigating harmful effects of the incident, preventing further compromises, and communicating information to affected parties, regulatory agencies and law enforcement, as necessary. The CSIRT may seek assistance from or engage external support providers including legal counsel, outside technology or forensic experts, investigation service providers, and others, as appropriate, to assist in the response to the incident, based on its nature and scope. Pursuant to the Plan and at the direction of WEC Energy Group's CAO, the Enterprise Security Director will conduct a post-incident remediation analysis and report findings to the CSIRT Steering Committee. The Plan is tested and reviewed at least annually.

We have been subject to attempted cybersecurity attacks from time to time, and will likely continue to be subject to such attempted attacks; however, these prior attacks have not had a material impact on our system or business operations. For information about cybersecurity risks to our business, see Item 1A. Risk Factors and the risk factor titled "Our operations are subject to risks beyond our control, including but not limited to, cybersecurity intrusions, terrorist or other physical attacks, acts of war, or unauthorized access to personally identifiable information."

2023 Form 10-K 29 Wisconsin Electric Power Company

ITEM 2. PROPERTIES

We own our principal properties outright. However, the major portion of our electric utility distribution lines, steam utility distribution mains and natural gas utility distribution mains and services are located on or under streets and highways, on land owned by others, and are generally subject to granted easements, consents, or permits. In addition, we lease the ERGS and PWGS generating units from We Power.

Electric Facilities

The following table summarizes information on generating assets we owned or leased from We Power as of December 31, 2023:

Name	Location	Fuel	Number of Generating Units	Capacity In MW (1)
Natural gas-fired plants
PWGS	Port Washington, WI	Natural Gas	2	1,217
Concord	Watertown, WI	Natural Gas/Oil	4	365
Paris	Union Grove, WI	Natural Gas/Oil	4	361
VAPP	Milwaukee, WI	Natural Gas	2	275
Germantown	Germantown, WI	Natural Gas/Oil	5	263
Whitewater	Whitewater, WI	Natural Gas/Oil	1	121	(2)
West Riverside	Beloit, WI	Natural Gas	2	85	(2)
Weston	Rothschild, WI	Natural Gas	7	65	(2)
Total natural gas-fired plants			27	2,752
Coal-fired plants
OCPP	Oak Creek, WI	Coal	4	1,103	(5)
ERGS	Oak Creek, WI	Coal	2	1,082	(2)
Total coal-fired plants			6	2,185
Wind facilities
Glacier Hills	Cambria, WI	Wind	90	162
Blue Sky	Fond du Lac, WI	Wind	88	145
Montfort	Montfort, WI	Wind	20	30
Total wind facilities			198	337
Other renewable facilities
Badger Hollow II	Iowa County, WI	Solar	40	100	(2)
Hydro plants (13 in number)	WI and MI	Hydro	30	46	(3)
Rothschild Biomass Plant	Rothschild, WI	Biomass	1	46	(4)
Total other renewable facilities			71	192
Total system			302	5,466

(1)    Capacity for our electric generation facilities, other than wind and solar generating facilities, is based on rated capacity, which is the net power output under average operating conditions with equipment in an average state of repair as of a given month in a given year. Values are primarily based on the net dependable expected capacity ratings for summer 2024 established by tests and may change slightly from year to year. The summer period is the most relevant for capacity planning purposes. This is a result of continually reaching demand peaks in the summer months, primarily due to air conditioning demand. Capacity for wind generating facilities is based on nameplate capacity, which is the amount of energy a turbine should produce at optimal wind speeds. Capacity for solar generating facilities is based on nameplate capacity, which is the maximum output that a generator should produce at continuous full power.

(2)    We jointly own these facilities with various other unaffiliated entities. The capacity indicated for each of these units is equal to our portion of total plant capacity based on its percent of ownership. See Note 9, Jointly Owned Utility Facilities, for more information

(3)     All of our hydroelectric facilities follow FERC guidelines and/or regulations.

(4)    We have a biomass power plant that uses wood waste and wood shavings to produce electric power as well as steam to support the paper mill's operations. Fuel for the power plant is supplied by both the paper mill and through contracts with biomass suppliers. The plant also has the ability to burn natural gas if wood waste and wood shavings are not available.

(5)    WEC Energy Group expects to retire approximately 1,800 MWs of additional fossil-fueled generation by the end of 2031, which includes the planned retirement in 2024-2025 of OCPP Units 5-8.

2023 Form 10-K 30 Wisconsin Electric Power Company

As of December 31, 2023, we operated approximately 19,500 miles of overhead distribution lines and approximately 26,300 miles of underground distribution cable, as well as approximately 300 electric distribution substations and approximately 303,300 line transformers.

Natural Gas Facilities

At December 31, 2023, our natural gas properties were located in three distinct service areas including west and south of the City of Milwaukee, the Appleton area, and areas within Iron and Vilas Counties, Wisconsin, and consisted of the following:

•Approximately 9,600 miles of natural gas distribution mains,

•Approximately 425,700 natural gas lateral services,

•Approximately 30 gas distribution and transmission gate stations,

•A 1.0 Bcf LNG plant located in southern Wisconsin, and

•LNG storage plants with a total send-out capability of 170,000 Dth per day.

Our natural gas distribution and gas storage systems included distribution and transmission mains connected to the pipeline transmission systems of ANR Pipeline Company, DTE Gas Company, Enbridge Gas Inc., Great Lakes Transmission Company, Guardian Pipeline L.L.C., Natural Gas Pipeline Company of America, Northern Natural Gas Company, and Vector Pipeline. Our LNG storage plant converts and stores, in liquefied form, natural gas received during periods of low consumption.

We also own office buildings, natural gas regulating and metering stations, and major service centers, including garage and warehouse facilities, in certain communities we serve. Where distribution lines and services and natural gas distribution mains and services occupy private property, we have in some, but not all instances, obtained consents, permits or easements for these installations from the apparent owners or those in possession of those properties, generally without an examination of ownership records or title.

Steam Facilities

As of December 31, 2023, the steam system supplied by the VAPP consisted of approximately 40 miles of both high pressure and low pressure steam piping, approximately four miles of walkable tunnels, and other pressure regulating equipment.

ITEM 3. LEGAL PROCEEDINGS

The following should be read in conjunction with Note 22, Commitments and Contingencies, and Note 24, Regulatory Environment, in this report for additional information on material legal proceedings and matters related to us.

In addition to those legal proceedings discussed in Note 22, Commitments and Contingencies, and Note 24, Regulatory Environment, and below, we are currently, and from time to time, subject to claims and suits arising in the ordinary course of business. Although the results of these additional legal proceedings cannot be predicted with certainty, management believes, after consultation with legal counsel, that the ultimate resolution of these proceedings will not have a material impact on our financial statements.

Employee Retirement Savings Plan Matter

In May 2022, a putative class action, Munt, et al. v. WEC Energy Group, Inc., et al., was filed in the United States District Court for the Eastern District of Wisconsin - Milwaukee Division. The plaintiffs allege that WEC Energy Group and others breached their fiduciary duties with respect to the operation and oversight of WEC Energy Group's Employee Retirement Saving Plan (the “Plan”) in violation of the Employee Retirement Income Security Act of 1974, as amended. The class is alleged to be participants in the Plan from

May 10, 2016 through the date of judgment. The complaint seeks injunctive relief, damages, interest, costs, and attorneys' fees. WEC Energy Group is vigorously defending against the allegations made in this lawsuit and intends to continue to do so.

ITEM 4. MINE SAFETY DISCLOSURES

Not applicable.

2023 Form 10-K 31 Wisconsin Electric Power Company

INFORMATION ABOUT OUR EXECUTIVE OFFICERS

The names, ages, and positions of our executive officers are listed below along with their business experience during the past five years. All officers are appointed until their resignation, death, or removal pursuant to our Bylaws. There are no family relationships among these officers, nor is there any agreement or understanding between any officer and any other person pursuant to which the officer was selected.

Robert M. Garvin. Age 57.

•WEC Energy Group — Executive Vice President - External Affairs since June 2015.

•WBS (a centralized service company of WEC Energy Group) – Executive Vice President - External Affairs since January 2019.

William J. Guc. Age 54.

•WEC Energy Group — Controller since October 2015. Vice President since June 2015.

•WE — Vice President and Controller since October 2015. Assistant Corporate Secretary since January 2020.

Margaret C. Kelsey. Age 59.

•WEC Energy Group — Executive Vice President, Corporate Secretary and General Counsel since January 2018.

•WE — Executive Vice President, Corporate Secretary and General Counsel since January 2018. Director since January 2018.

Scott J. Lauber. Age 58.

•WEC Energy Group — President and Chief Executive Officer since February 1, 2022. Senior Executive Vice President and Chief Operating Officer from June 2020 to January 31, 2022. Senior Executive Vice President and Chief Financial Officer from October 2019 to June 2020. Senior Executive Vice President, Chief Financial Officer and Treasurer from February 2019 to October 2019. Executive Vice President, Chief Financial Officer and Treasurer from October 2018 to February 2019. Director since February 1, 2022.

•WE — Chairman of the Board and Chief Executive Officer since February 1, 2022. President since January 1, 2022. Executive Vice President from June 2020 to December 31, 2021. Executive Vice President and Chief Financial Officer from October 2019 to June 2020. Executive Vice President, Chief Financial Officer and Treasurer from October 2018 to October 2019. Director since April 2016.

Xia Liu. Age 54.

•WEC Energy Group — Executive Vice President and Chief Financial Officer since June 2020.

•WE — Executive Vice President and Chief Financial Officer since June 2020. Director since June 2020.

•CenterPoint Energy, Inc. – Senior Advisor from April 2020 to May 2020. Executive Vice President and Chief Financial Officer from April 2019 to April 2020. CenterPoint Energy, Inc. is a public utility holding company whose operating subsidiaries provide electric and natural gas service to customers in parts of the South and Midwest.

•Georgia Power Company – Executive Vice President, Chief Financial Officer and Treasurer from October 2017 to April 2019. Georgia Power Company is a utility subsidiary of The Southern Company that provides electric service to customers throughout Georgia.

William Mastoris. Age 60.

•WBS (a centralized service company of WEC Energy Group) – Executive Vice President – Customer Service and Operations since December 2021. Vice President – Supply Chain and Fleet from January 2019 through November 2021. Director since November 2021.

•WE – Executive Vice President – Customer Service and Operations since December 2021. Director since November 2021.

Anthony L. Reese. Age 42.

•WEC Energy Group — Vice President and Treasurer since October 2019.

•WE — Vice President and Treasurer since October 2019.

•The Peoples Gas Light and Coke Company – Controller - Illinois from September 2015 to September 2019.

Certain executive officers also hold officer and/or director positions at WEC Energy Group's other significant subsidiaries.

2023 Form 10-K 32 Wisconsin Electric Power Company

PART II

ITEM 5. MARKET FOR REGISTRANT'S COMMON EQUITY, RELATED STOCKHOLDER MATTERS AND ISSUER PURCHASES OF EQUITY SECURITIES

There is no established public trading market for our common stock, as WEC Energy Group owns all of our outstanding common stock. See Note 11, Common Equity, for more information.

ITEM 6. RESERVED

2023 Form 10-K 33 Wisconsin Electric Power Company

ITEM 7. MANAGEMENT'S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND RESULTS OF OPERATIONS

CORPORATE DEVELOPMENTS

Introduction

We are a wholly owned subsidiary of WEC Energy Group, and derive revenues from the distribution and sale of electricity and natural gas to retail customers in Wisconsin. We also provide wholesale electric service to numerous utilities and cooperatives for resale. We conduct our business primarily through our utility reportable segment. See Note 20, Segment Information, for more information on our reportable business segments.

Corporate Strategy

Our goal is to continue to build and sustain long-term value for our customers and WEC Energy Group's shareholders by focusing on the fundamentals of our business: environmental stewardship; reliability; operating efficiency; financial discipline; exceptional customer care; and safety. WEC Energy Group's capital investment plan for efficiency, sustainability and growth, referred to as its ESG Progress Plan, provides a roadmap to achieve this goal. It is an aggressive plan to cut emissions, maintain superior reliability, deliver significant savings for customers, and grow WEC Energy Group's and our investment in the future of energy.

Throughout its strategic planning process, WEC Energy Group takes into account important developments, risks and opportunities, including new technologies, customer preferences and affordability, energy resiliency efforts, and sustainability.

Creating a Sustainable Future

WEC Energy Group's ESG Progress Plan includes the retirement of older, fossil-fueled generation, to be replaced with zero-carbon-emitting renewables and clean natural gas-fired generation at its electric utilities, including us. The retirements will contribute to meeting WEC Energy Group's and our goals to reduce CO2 emissions from electric generation. When taken together, the retirements and new investments in renewables and clean generation should better balance supply with demand, while maintaining reliable, affordable energy for our customers.

WEC Energy Group announced goals to achieve reductions in carbon emissions from its electric generation fleet by 60% by the end of 2025 and by 80% by the end of 2030, both from a 2005 baseline. WEC Energy Group expects to achieve these goals by continuing to make operating refinements, retiring less efficient generating units, and executing its capital plan. Over the longer term, the target for its generation fleet is to be net carbon neutral by 2050.

As part of our path toward these goals, we have started implementing co-firing with natural gas at the ERGS coal-fired units. By the end of 2030, WEC Energy Group expects to use coal as a backup fuel only, and WEC Energy Group believes it will be in a position to eliminate coal as an energy source by the end of 2032.

WEC Energy Group already has retired more than 1,900 MWs of coal-fired generation since the beginning of 2018, which included the 2019 retirement of the PIPP as well as the 2018 retirement of the Pleasant Prairie power plant. See Note 7, Regulatory Assets and Liabilities, for more information related to these power plant retirements. WEC Energy Group expects to retire approximately 1,800 MWs of additional fossil-fueled generation by the end of 2031, which includes the planned retirement in 2024-2025 of OCPP Units 5-8. See Note 8, Property, Plant, and Equipment, for more information related to the planned OCPP retirements.

In addition to retiring these older, fossil-fueled plants, WEC Energy Group expects to invest approximately $7.0 billion from 2024-2028 in regulated renewable energy in Wisconsin. WEC Energy Group's plan is to replace a portion of the retired capacity by building and owning zero-carbon-emitting renewable generation facilities that are anticipated to include the following new investments made by either us or WPS based on specific customer needs:

•2,700 MWs of utility-scale solar;

•880 MWs of wind; and

•250 MWs of battery storage.

2023 Form 10-K 34 Wisconsin Electric Power Company

WEC Energy Group also plans on investing in a combination of clean, natural gas-fired generation, made by either us or WPS based on specific customer needs, including:

•1,125 MWs of combustion turbines;

•132 MWs of RICE natural gas-fueled generation; and

•the purchase of 100 MWs of additional capacity in West Riverside.

For more details, see Liquidity and Capital Resources – Cash Requirements – Significant Capital Projects.

In December 2018, we received approval from the PSCW for two renewable energy pilot programs. The Solar Now pilot is expected to add a total of 35 MWs of solar generation to our portfolio, allowing non-profit and government entities, as well as commercial and industrial customers, to site utility owned solar arrays on their property. Under this program, we have energized 28 Solar Now projects and currently have another one under construction, together totaling more than 30 MWs. The second program, the DRER pilot, is designed to allow large commercial and industrial customers to access renewable resources that we would operate. The DRER pilot is intended to help these larger customers meet their sustainability and renewable energy goals, and could add up to 35 MWs of renewables to our portfolio. In July 2023, the PSCW approved the Renewable Pathway Pilot, the third renewable energy program. This program allows our commercial and industrial customers to subscribe to a portion of a utility-scale, Wisconsin-based renewable energy generating facility for up to 125 MWs.

In August 2021, the PSCW approved pilot programs for us to install and maintain EV charging equipment for customers at their homes or businesses. The programs provide direct benefits to customers by removing cost barriers associated with installing EV equipment. In October 2021, subject to the receipt of any necessary regulatory approvals, WEC Energy Group pledged to expand the EV charging network within its utilities' electric service territories. In doing so, WEC Energy Group joined a coalition of utility companies in a unified effort to make EV charging convenient and widely available throughout the Midwest. The coalition WEC Energy Group joined is planning to help build and grow EV charging corridors, enabling the general public to safely and efficiently charge their vehicles.

WEC Energy Group also continues to reduce methane emissions by improving its natural gas distribution system, and has set a target across its natural gas distribution operations to achieve net-zero methane emissions by the end of 2030. WEC Energy Group plans to achieve its net-zero goal through an effort that includes both continuous operational improvements and equipment upgrades, as well as the use of RNG throughout its natural gas utility systems. In 2022, we received approval from the PSCW for an RNG pilot associated with our natural gas distribution system.

In December 2023, WEC Energy Group started a pilot program with the Electric Power Research Institute and CMBlu Energy, a Germany-based designer and manufacturer, to test a new form of long-duration energy storage on the U.S. electric grid. The program will test battery system performance, including the ability to store and discharge energy for up to twice as long as the typical lithium-ion batteries in use today. WEC Energy Group expects the full pilot to be completed in 2024.

Reliability

We have made significant reliability-related investments in recent years, and in accordance with the ESG Progress Plan, expect to continue strengthening and modernizing our generation fleet, as well as our electric and natural gas distribution networks to further improve reliability.

We constructed an LNG facility that was placed into commercial operation at the end of 2023. The facility will provide approximately one Bcf of natural gas supply to meet anticipated peak demand without requiring the construction of additional interstate pipeline capacity.

Included in the WEC Energy Group capital plan, are our additional proposed LNG storage facilities providing approximately three Bcf of natural gas supply, which is needed to ensure gas supply for winter reliability.

For more details, see Liquidity and Capital Resources – Cash Requirements – Significant Capital Projects.

2023 Form 10-K 35 Wisconsin Electric Power Company

Operating Efficiency

We continually look for ways to optimize the operating efficiency of our company and will continue to do so under the ESG Progress Plan. For example, we are making progress on our AMI program, replacing aging meter-reading equipment on both our network and customer property. An integrated system of smart meters, communication networks, and data management programs enables two-way communication between us and our customers. This program reduces the manual effort for disconnects and reconnects and enhances outage management capabilities.

WEC Energy Group continues to focus on integrating the resources of its businesses and finding the best and most efficient processes.

Financial Discipline

A strong adherence to financial discipline is essential to meeting our earnings projections and maintaining a strong balance sheet, stable cash flows, and quality credit ratings.

We follow an asset management strategy that focuses on investing in and acquiring assets consistent with our strategic plans, as well as disposing of assets, including property, plants, and equipment, that are no longer strategic to operations, are not performing as intended, or have an unacceptable risk profile. See Note 2, Acquisitions, for more information on our recent acquisitions. See Note 3, Disposition, for more information on a recent transaction.

Exceptional Customer Care

Our approach is driven by an intense focus on delivering exceptional customer care every day. We strive to provide the best value for our customers by demonstrating personal responsibility for results, leveraging our capabilities and expertise, and using creative solutions to meet or exceed our customers’ expectations.

A multiyear effort is driving a standardized, seamless approach to digital customer service across all of the WEC Energy Group companies. It has moved all utilities, including us, to a common platform for all customer-facing self-service options. Using common systems and processes reduces costs, provides greater flexibility and enhances the consistent delivery of exceptional service to customers.

Safety

Safety is one of our core values and a critical component of our culture. We are committed to keeping our employees and the public safe through a comprehensive corporate safety program that focuses on employee engagement and elimination of at-risk behaviors.

Under our "Target Zero" mission, we have an ultimate goal of zero incidents, accidents, and injuries. Management and union leadership work together to reinforce the Target Zero culture. We set annual goals for safety results as well as measurable leading indicators, in order to raise awareness of at-risk behaviors and situations and guide injury-prevention activities. All employees are encouraged to report unsafe conditions or incidents that could have led to an injury. Injuries and tasks with high levels of risk are assessed, and findings and best practices are shared across the WEC Energy Group companies.

Our corporate safety program provides a forum for addressing employee concerns, training employees and contractors on current safety standards, and recognizing those who demonstrate a safety focus.

RESULTS OF OPERATIONS

The following discussion and analysis of our Results of Operations includes comparisons of our results for the year ended December 31, 2023 with the year ended December 31, 2022. For a similar discussion that compares our results for the year ended December 31, 2022 with the year ended December 31, 2021, see Item 7. Management's Discussion and Analysis of Financial Condition and Results of Operations – Results of Operations in Part II of our 2022 Annual Report on Form 10-K, which was filed with the SEC on February 23, 2023.

2023 Form 10-K 36 Wisconsin Electric Power Company

Consolidated Earnings

Our earnings for the year ended December 31, 2023 were $480.6 million, compared with $396.7 million for the year ended December 31, 2022. See below for additional information on the $83.9 million increase in earnings.

Non-GAAP Financial Measures

The discussion below addresses the contribution of our utility segment to net income attributed to common shareholder. The discussion includes financial information prepared in accordance with GAAP, as well as electric margins and natural gas margins, which are not measures of financial performance under GAAP. Electric margins (electric revenues less fuel and purchased power costs) and natural gas margins (natural gas revenues less cost of natural gas sold) are non-GAAP financial measures because they exclude other operation and maintenance expense, depreciation and amortization, and property and revenue taxes.

We believe that electric and natural gas margins provide a useful basis for evaluating utility operations since the majority of prudently incurred fuel and purchased power costs, as well as prudently incurred natural gas costs, are passed through to customers in current rates. As a result, management uses electric and natural gas margins internally when assessing the operating performance of our utility segment as these measures exclude the majority of revenue fluctuations caused by changes in these expenses. Similarly, the presentation of electric and natural gas margins herein is intended to provide supplemental information for investors regarding our operating performance.

Our electric margins and natural gas margins may not be comparable to similar measures presented by other companies. Furthermore, these measures are not intended to replace operating income as determined in accordance with GAAP as an indicator of operating performance. Our utility segment operating income for the years ended December 31, 2023 and 2022 was $1,022.2 million and $940.0 million, respectively. The discussion below includes a table that provides the calculation of electric margins and natural gas margins, along with a reconciliation to the most directly comparable GAAP measure, operating income.

Utility Segment Contribution to Net Income Attributed to Common Shareholder

	Year Ended December 31
(in millions)	2023		2022		B (W)
Electric revenues	$	3,553.5	$	3,461.8	$	91.7
Fuel and purchased power	1,178.9		1,274.0		95.1
Total electric margins	2,374.6		2,187.8		186.8
Natural gas revenues	491.5		608.5		(117.0)
Cost of natural gas sold	272.5		419.3		146.8
Total natural gas margins	219.0		189.2		29.8
Total electric and natural gas margins	2,593.6		2,377.0		216.6
Other operation and maintenance	931.1		831.7		(99.4)
Depreciation and amortization	525.0		479.7		(45.3)
Property and revenue taxes	115.3		125.6		10.3
Operating income	1,022.2		940.0		82.2
Other income, net	68.8		49.4		19.4
Interest expense	466.5		458.4		(8.1)
Income before income taxes	624.5		531.0		93.5
Income tax expense	142.7		133.1		(9.6)
Preferred stock dividend requirements	1.2		1.2		—
Net income attributed to common shareholder	$	480.6	$	396.7	$	83.9

2023 Form 10-K 37 Wisconsin Electric Power Company

The following table shows a breakdown of other operation and maintenance:

	Year Ended December 31
(in millions)	2023		2022		B (W)
Operation and maintenance not included in line items below	$	329.1	$	357.7	$	28.6
Transmission (1)	357.3		275.8		(81.5)
We Power (2)	141.4		108.1		(33.3)
Regulatory amortizations and other pass through expenses (3)	97.1		69.7		(27.4)
Earnings sharing mechanism (4)	5.6		—		(5.6)
Other	0.6		20.4		19.8
Total other operation and maintenance	$	931.1	$	831.7	$	(99.4)

(1)    Represents transmission expense that we are authorized to collect in rates. The PSCW has approved escrow accounting for ATC and MISO network transmission expenses. As a result, we defer as a regulatory asset or liability, the difference between actual transmission costs and those included in rates until recovery or refund is authorized in a future rate proceeding. During 2023 and 2022, $339.0 million and $340.0 million, respectively, of costs were billed to us by transmission providers.

During 2022, we amortized $62.0 million of the regulatory liability associated with our transmission escrow to offset certain 2022 revenue deficiencies, as approved by the PSCW in order to forego filing for 2022 base rate increases. This amortization drove the lower transmission expense during 2022.

(2)    Represents costs associated with the We Power generation units, including operating and maintenance costs we recognized. During 2023 and 2022, $124.5 million and $121.7 million, respectively, of costs were billed to or incurred by us related to the We Power generation units, with the difference in costs billed or incurred and expenses recognized, either deferred or deducted from the regulatory asset.

(3)    Regulatory amortizations and other pass through expenses are substantially offset in margins and therefore do not have a significant impact on net income. Effective January 1, 2023, the PSCW approved escrow accounting for pension and OPEB costs. As a result, we defer as a regulatory asset or liability, the difference between these actual costs and those included in rates until recovery or refund is authorized in a future rate proceeding.

(4)    Represents operation and maintenance associated with the earnings sharing mechanism we have in place. See Note 24, Regulatory Environment, for more information.

The following tables provide information on delivered sales volumes by customer class and weather statistics:

	Year Ended December 31
	MWh (in thousands)
Electric Sales Volumes	2023	2022	B (W)
Customer class
Residential	7,791.0	8,099.8	(308.8)
Small commercial and industrial	8,545.1	8,655.9	(110.8)
Large commercial and industrial	6,475.1	6,655.9	(180.8)
Other	103.7	110.2	(6.5)
Total retail	22,914.9	23,521.8	(606.9)
Wholesale	542.3	857.5	(315.2)
Resale	5,638.2	3,618.7	2,019.5
Total sales in MWh	29,095.4	27,998.0	1,097.4

	Year Ended December 31
	Therms (in millions)
Natural Gas Sales Volumes	2023	2022	B (W)
Customer class
Residential	341.6	400.1	(58.5)
Commercial and industrial	200.8	224.9	(24.1)
Total retail	542.4	625.0	(82.6)
Transportation	231.7	324.2	(92.5)
Total sales in therms	774.1	949.2	(175.1)

2023 Form 10-K 38 Wisconsin Electric Power Company

	Year Ended December 31
	Degree Days
Weather (1)	2023	2022	B (W)
Heating (6,509 Normal)	5,409	6,369	(15.1)	%
Cooling (775 Normal)	876	944	(7.2)	%

(1)    Normal degree days are based on a 20-year moving average of monthly temperatures from Mitchell International Airport in Milwaukee, Wisconsin.

Electric Revenues

Electric revenues increased $91.7 million during 2023, compared with 2022. To the extent that changes in fuel and purchased power costs are passed through to customers, the changes are offset by comparable changes in revenues. The remaining drivers of changes in electric revenues are described in the discussion of electric utility margins below.

Electric Utility Margins

Electric utility margins increased $186.8 million during 2023, compared with 2022. The significant factors impacting the higher electric utility margins were:

•A $245.2 million increase in margins related to the impact of our rate order approved by the PSCW, effective January 1, 2023.

•A $15.7 million increase in margins during 2023, related to the expiration of a capacity purchase contract driven by the acquisition of the Whitewater facility, effective January 1, 2023.

These increases in margins were partially offset by:

•A $49.5 million decrease in margins related to lower retail electric sales volumes, including steam operations, driven by the impact of unfavorable weather during 2023, compared with 2022. As measured by cooling degree days, 2023 was 7.2% cooler than 2022. As measured by heating degree days, 2023 was 15.1% warmer than 2022.

•A $13.2 million decrease in other revenues, primarily related to third-party use of our assets and a FERC order in January 2023 that eliminated reactive power compensation MISO was required to pay to generators, including us. The decrease in reactive power revenues is substantially offset by a decrease in transmission expense related to a deferral of these revenues as a component of our transmission escrow, as approved by the PSCW in June 2023 and discussed below.

•Lower margins of $8.0 million driven by the expiration of a wholesale contract in May 2022.

Natural Gas Revenues

Natural gas revenues decreased $117.0 million during 2023, compared with 2022. Because prudently incurred natural gas costs are passed through to our customers in current rates, the changes are offset by comparable changes in revenues. The average per-unit cost of natural gas decreased approximately 29% during 2023, compared with 2022. The remaining drivers of changes in natural gas revenues are described in the discussion of natural gas utility margins below.

Natural Gas Utility Margins

Natural gas utility margins increased $29.8 million during 2023, compared with 2022. The most significant factor impacting the higher natural gas utility margins was a $48.8 million increase in margins related to the impact of our rate order approved by the PSCW, effective January 1, 2023. This increase in margins was partially offset by a $19.5 million decrease in margins from lower sales volumes, driven by the impact of unfavorable weather during 2023, compared with 2022.

2023 Form 10-K 39 Wisconsin Electric Power Company

Other Operating Expenses (includes other operation and maintenance, depreciation and amortization, and property and revenue taxes)

Other operating expenses at the utility segment increased $134.4 million during 2023, compared with 2022. The significant factors impacting the increase in other operating expenses were:

•An $81.5 million increase in transmission expense as approved in the PSCW's 2023 rate order, effective January 1, 2023. See the notes under the other operation and maintenance table above for more information. This amount is net of a deferral of $5.3 million approved by the PSCW in June 2023, retroactive to December 1, 2022, in response to a FERC order eliminating reactive power compensation, as discussed in electric margins above.

•A $45.3 million increase in depreciation and amortization, driven by assets being placed into service as we continue to execute on our capital plan.

•A $33.3 million increase in other operation and maintenance expense related to the We Power leases, as discussed in the notes under the other operation and maintenance table above.

•A $27.4 million increase in regulatory amortizations and other pass through expenses, as discussed in the notes under the other operation and maintenance table above.

•A $23.4 million increase in other operating and maintenance related to our power plants, driven by increases to certain plant-related regulatory assets in 2022 as a result of the December 2022 Wisconsin rate order as well as operating costs associated with Whitewater, which we purchased in January 2023. These increases were partially offset by lower severance during 2023.

•A $5.6 million increase in expense related to the earnings sharing mechanism we have in place, as discussed in the notes under the other operation and maintenance table above.

These increases in other operating expenses were partially offset by:

•A $21.6 million increase in pre-tax gains on the sale of land, primarily at the site of our former Pleasant Prairie power plant in 2023.

•A $19.8 million decrease in expense primarily related to lower commitments made in 2023 to fund our charitable foundation.

•A $10.3 million decrease in property and revenue taxes during 2023, compared with 2022.

•A $5.5 million decrease in expense related to environmental remediation and related studies.

•A $4.0 million decrease in expenses associated with the settlement of legal claims.

•A $3.9 million decrease in benefit costs, driven by lower stock-based compensation, partially offset by an increase in deferred compensation costs.

•A $3.7 million decrease in electric and natural gas distribution expenses, driven by lower costs to maintain the distribution system during 2023, compared with 2022.

Other Income, Net

Other income, net increased $19.4 million during 2023, compared with 2022, driven by higher AFUDC-Equity due to continued capital investment. See Note 25, Other Income, Net, for more information.

Interest Expense

Interest expense increased $8.1 million during 2023, compared with 2022, driven by the impact of higher long-term debt balances related to a $500.0 million issuance in September 2022, and higher short-term debt interest rates. The increase was partially offset

2023 Form 10-K 40 Wisconsin Electric Power Company

by higher AFUDC-Debt due to continued capital investment and lower interest expense on finance lease liabilities, primarily related to the We Power leases, as finance lease liabilities decrease each year as payments are made.

Income Tax Expense

Income tax expense increased $9.6 million during 2023, compared with 2022, primarily due to higher pre-tax income. This increase in income tax expense was partially offset by a $9.3 million increase in PTCs and a $4.7 million increase in income tax benefits associated with AFUDC-Equity, both driven by continued capital investment.

LIQUIDITY AND CAPITAL RESOURCES

Overview

We expect to maintain adequate liquidity to meet our cash requirements for operation of our business and implementation of our corporate strategy through internal generation of cash from operations and access to the capital markets.

The following discussion and analysis of our Liquidity and Capital Resources includes comparisons of our cash flows for the year ended December 31, 2023 with the year ended December 31, 2022. For a similar discussion that compares our cash flows for the year ended December 31, 2022 with the year ended December 31, 2021, see Item 7. Management's Discussion and Analysis of Financial Condition and Results of Operations – Liquidity and Capital Resources in Part II of our 2022 Annual Report on Form 10-K, which was filed with the SEC on February 23, 2023.

Cash Flows

The following table summarizes our cash flows during the years ended December 31:

(in millions)	2023		2022		Change in 2023 Over 2022
Cash provided by (used in):
Operating activities	$	939.1	$	637.0	$	302.1
Investing activities	(1,227.3)		(914.0)		(313.3)
Financing activities	248.0		321.7		(73.7)

Operating Activities

Net cash provided by operating activities increased $302.1 million during 2023, compared with 2022, driven by:

•A $441.7 million increase in cash from lower payments for fuel and purchased power at our generation plants, as well as lower natural gas costs related to the natural gas sold to our customers during 2023, compared with 2022, primarily driven by a decrease in the price of natural gas.

•A $79.7 million increase in cash from higher overall collections from customers during 2023, compared with 2022. This increase was driven by the impact of our rate order approved by the PSCW, effective January 1, 2023. See Note 24, Regulatory Environment, for more information, on our 2023 rate order.

These increases in net cash provided by operating activities were partially offset by:

•A $115.2 million decrease in cash driven by collateral paid to counterparties during 2023, compared with collateral received from counterparties during 2022, as well as realized losses on derivative instruments recognized during 2023, compared with realized gains recognized during 2022.

•A $73.5 million decrease in cash related to higher payments for other operation and maintenance expenses. During 2023, our payments were higher associated with previous commitments to charitable projects and operating and maintenance related to our electric generating units and those we lease from We Power.

2023 Form 10-K 41 Wisconsin Electric Power Company

•A $14.6 million decrease in cash from higher payments for interest, driven by the issuance of long-term debt in September 2022, and higher average short-term debt interest rates during 2023, compared with 2022.

•An $11.5 million decrease in cash related to higher payments for property and revenue taxes during 2023, compared with 2022, driven by the timing of payments for gross receipt taxes payable.

•An $11.1 million decrease in cash related to higher cash paid for income taxes, driven by higher taxable income during 2023, compared with 2022, partially offset by proceeds received in 2023 related to PTCs that were sold to a third party.

Investing Activities

Net cash used in investing activities increased $313.3 million during 2023, compared with 2022, driven by:

•A $164.2 million increase in cash paid for capital expenditures, which is discussed in more detail below.

•The acquisition of a 13.8% ownership interest in West Riverside in June 2023 for $95.3 million. See Note 2, Acquisitions, for more information.

•Insurance proceeds of $41.0 million received during 2022, for property damage related to the PSB water damage claim. See Note 8, Property, Plant, and Equipment, for more information.

•The acquisition of a 50% ownership interest in Whitewater in January 2023 for $38.0 million. See Note 2, Acquisitions, for more information.

These increases in net cash used in investing activities were partially offset by proceeds received of $24.3 million during 2023, driven by the sale of land at the site of our former Pleasant Prairie power plant. See Note 3, Disposition, for more information.

Capital Expenditures

Capital expenditures for the years ended December 31 were as follows:

(in millions)	2023		2022		Change in 2023 Over 2022
Capital expenditures	$	1,094.6	$	930.4	$	164.2

The increase in cash paid for capital expenditures during 2023, compared with 2022, was driven by higher payments related to renewable energy projects, upgrades to our electric distribution system, and the construction of our LNG facility. These increases were partially offset by lower payments for capital expenditures related to our share of the natural gas-fired generation constructed at WPS's Weston power plant site.

See Liquidity and Capital Resources – Cash Requirements – Significant Capital Projects below for more information.

Financing Activities

Net cash provided by financing activities decreased $73.7 million during 2023, compared with 2022, driven by:

•A $500.0 million decrease in cash due to issuances of long-term debt during 2022. We did not issue any long-term debt during 2023.

•A $185.6 million decrease in cash due to $99.9 million of net repayments of commercial paper during 2023, compared with $85.7 million of net borrowings of commercial paper during 2022.

These decreases in net cash provided by financing activities were partially offset by:

•A $350.0 million increase in cash related to higher equity contributions received from our parent during 2023, compared with 2022, to balance our capital structure.

2023 Form 10-K 42 Wisconsin Electric Power Company

•A $260.0 million increase in cash due to lower dividends paid to our parent during 2023, compared with 2022, to balance our capital structure.

Significant Financing Activities

For more information on our financing activities, see Note 13, Short-Term Debt and Lines of Credit, and Note 14, Long-Term Debt.

Cash Requirements

We require funds to support and grow our business. Our significant cash requirements primarily consist of capital and investment expenditures, payments to retire and pay interest on long-term debt, the payment of common stock dividends to our parent, and the funding of our ongoing operations. Our significant cash requirements are discussed in further detail below.

Significant Capital Projects

We have several capital projects that will require significant capital expenditures over the next three years and beyond. All projected capital requirements are subject to periodic review and may vary significantly from estimates, depending on a number of factors. These factors include environmental requirements, regulatory restraints and requirements, changes in tax laws and regulations, acquisition and development opportunities, market volatility, economic trends, supply chain disruptions, inflation, and interest rates. Our estimated capital expenditures and acquisitions for the next three years are reflected below. These amounts include anticipated expenditures for environmental compliance and certain remediation issues. For a discussion of certain environmental matters affecting us, see Note 22, Commitments and Contingencies.

(in millions)
2024	$	1,740.0
2025	2,035.7
2026	2,235.5
Total	$	6,011.2

We continue to upgrade our electric and natural gas distribution systems to enhance reliability. These upgrades include addressing our aging infrastructure, system hardening, and the AMI program. AMI is an integrated system of smart meters, communication networks, and data management systems that enable two-way communication between utilities and customers.

WEC Energy Group is committed to investing in solar, wind, battery storage, and clean natural gas-fired generation. Below are examples of projects that are proposed or currently underway.

•We, along with WPS and an unaffiliated utility, received PSCW approval to acquire and construct Paris, a utility-scale solar-powered electric generating facility with a battery energy storage system. The project will be located in Kenosha County, Wisconsin and once fully constructed, we will own 150 MWs of solar generation and 82 MWs of battery storage of this project. Our share of the cost of this project is estimated to be approximately $452 million, with construction of the solar portion and battery storage expected to be completed in 2024 and 2025, respectively.

•We, along with WPS and an unaffiliated utility, received PSCW approval to acquire and construct Darien, a utility-scale solar-powered electric generating facility. The project will be located in Rock and Walworth counties, Wisconsin and once fully constructed, we will own 188 MWs of solar generation. Our share of the cost of this project is estimated to be approximately $337.5 million, with construction expected to be completed in 2024. As part of its order, the PSCW approved battery capacity at this project, which is no longer included in the current capital plan. We will continue to evaluate timing, cost, and feasibility of the installation of batteries.

•We, along with WPS and an unaffiliated utility, received PSCW approval to acquire Koshkonong, a utility-scale solar-powered electric generating facility. The project will be located in Dane County, Wisconsin and once fully constructed, we will own 225 MWs of solar generation. Our share of the cost of this project is estimated to be approximately $405 million, with construction expected to be completed in 2026. As part of its order, the PSCW approved battery capacity at this project, which is no longer included in the current capital plan. We will continue to evaluate timing, cost, and feasibility of the installation of batteries.

2023 Form 10-K 43 Wisconsin Electric Power Company

•In September 2023, WPS filed a request with the PSCW to exercise a second option to acquire an additional 100 MWs of capacity in West Riverside, a combined cycle natural gas plant operated by an unaffiliated utility in Rock County, Wisconsin. In October 2023, WPS filed for approval to assign the second option to purchase West Riverside to us. If approved, our share of the cost of this ownership interest is expected to be approximately $100 million, with the transaction expected to close in 2024.

•We plan to enhance fuel flexibility at the coal-fired ERGS units.

•In February 2024, we, along with WPS and an unaffiliated utility, filed a request with the PSCW to acquire and construct High Noon, a utility-scale solar-powered electric generating facility. The project will be located in Columbia County, Wisconsin and once fully constructed, we will own 225 MWs of solar generation of this project. If approved, our share of the cost of this project is estimated to be approximately $480 million, with construction expected to be completed by the end of 2026. Approval for battery capacity at this project was also requested, which is not included in the current capital plan. We will continue to evaluate the timing, cost, and feasibility of the installation of batteries.

In August 2023, the DOC issued a ruling in its investigation into whether new tariffs should be imposed on solar panels and cells imported from multiple southeast Asian countries. See Factors Affecting Results, Liquidity, and Capital Resources – Regulatory, Legislative, and Legal Matters – United States Department of Commerce Complaint and Factors Affecting Results, Liquidity, and Capital Resources – Regulatory, Legislative, and Legal Matters – Uyghur Forced Labor Prevention Act for information on the potential impacts to our solar projects as a result of the DOC ruling and CBP actions related to solar panels, respectively. The expected in-service dates and costs identified above already reflect some of these impacts.

The construction of additional LNG facilities has been proposed as part of WEC Energy Group's 2024 -2028 capital plan, which includes us. The facilities would provide approximately four Bcf of natural gas supply (of which our portion is expected to be approximately three Bcf) and are expected to reduce the likelihood of constraints on the natural gas systems during the highest demand days of winter. The total cost of the four Bcf projects is estimated to be approximately $860 million.

Long-Term Debt

A significant amount of cash is required to retire and pay interest on our long-term debt obligations. See Note 14, Long-Term Debt, for more information on our outstanding long-term debt, including a schedule of our long-term debt maturities over the next five years. The following table summarizes our required interest payments on long-term debt (excluding finance lease obligations) as of December 31, 2023:

	Interest Payments Due by Period
(in millions)	Total		Less Than 1 Year		1-3 Years		3-5 Years		More Than 5 Years
Interest payments due on long-term debt	$	2,136.3	$	139.9	$	255.4	$	243.2	$	1,497.8

Common Stock Dividends

During the years ended December 31, 2023, 2022, and 2021, we paid common stock dividends of $370.0 million, $630.0 million, and $360.0 million, respectively, to the sole holder of our common stock, WEC Energy Group. Any payment of future dividends is subject to approval by our Board of Directors and is dependent upon future earnings, capital requirements, and financial and other business conditions. In addition, various financing arrangements and regulatory requirements impose certain restrictions on our ability to transfer funds to WEC Energy Group in the form of cash dividends, loans, or advances. We do not believe that these restrictions will materially affect our operations or limit any dividend payments in the foreseeable future. See Note 11, Common Equity, for more information related to these restrictions and our other common stock matters.

Other Significant Cash Requirements

Our utility operations have purchase obligations under various contracts for the procurement of fuel, power, and gas supply, as well as the related storage and transportation. These costs are a significant component of funding our ongoing operations. See Note 22, Commitments and Contingencies, for more information, including our minimum future commitments related to these purchase obligations.

2023 Form 10-K 44 Wisconsin Electric Power Company

In addition to our energy-related purchase obligations, we have commitments for other costs incurred in the normal course of business, including costs related to information technology services, meter reading services, maintenance and other service agreements for certain generating facilities, and various engineering agreements. Our estimated future cash requirements related to these purchase obligations, excluding energy-related obligations, are reflected below.

	Payments Due by Period
(in millions)	Total		Less Than 1 Year		1-3 Years		3-5 Years		More Than 5 Years
Purchase orders	$	220.3	$	104.5	$	108.3	$	7.3	$	0.2

We have various finance and operating lease obligations. Our finance lease obligations primarily relate to power purchase commitments and land leases for Badger Hollow II. Our operating lease obligations are for office space and land. See Note 15, Leases, for more information, including an analysis of our minimum lease payments due in future years.

We make contributions to our pension and OPEB plans based upon various factors affecting us, including our liquidity position and tax law changes. See Note 19, Employee Benefits, for our expected contributions in 2024 and our expected pension and OPEB payments for the next 10 years. We expect the majority of these future pension and OPEB payments to be paid from our outside trusts. See Sources of Cash–Investments in Outside Trusts below for more information.

In addition to the above, our balance sheet at December 31, 2023 included various other liabilities that, due to the nature of the liabilities, the amount and timing of future payments cannot be determined with certainty. These liabilities include AROs, liabilities for the remediation of manufactured gas plant sites, and liabilities related to the accounting treatment for uncertainty in income taxes. For additional information on these liabilities, see Note 10, Asset Retirement Obligations, Note 22, Commitments and Contingencies, and Note 16, Income Taxes, respectively.

Off-Balance Sheet Arrangements

We are a party to various financial instruments with off-balance sheet risk as a part of our normal course of business, including letters of credit that primarily support our commodity contracts. We believe that these agreements do not have, and are not reasonably likely to have, a current or future material effect on our financial condition, changes in financial condition, revenues or expenses, results of operations, liquidity, capital expenditures, or capital resources. See Note 1(q), Guarantees, Note 13, Short-Term Debt and Lines of Credit, and Note 21, Variable Interest Entities, for more information.

Sources of Cash

Liquidity

We anticipate meeting our short-term and long-term cash requirements to operate our business and implement our corporate strategy through internal generation of cash from operations, equity contributions from our parent, and access to the capital markets, which allows us to obtain external short-term borrowings, including commercial paper, and intermediate or long-term debt securities. Cash generated from operations is primarily driven by sales of electricity and natural gas to our utility customers, reduced by costs of operations. Our access to the capital markets is critical to our overall strategic plan and allows us to supplement cash flows from operations with external borrowings to manage seasonal variations, working capital needs, commodity price fluctuations, unplanned expenses, and unanticipated events.

We maintain a bank back-up credit facility, which provides liquidity support for our obligations with respect to commercial paper and for general corporate purposes. We review our bank back-up credit facility needs on an ongoing basis and expect to be able to maintain adequate credit facilities to support our operations.

The amount, type, and timing of any financings in 2024, as well as in subsequent years, will be contingent on investment opportunities and our cash requirements and will depend upon prevailing market conditions, regulatory approvals, and other factors. We plan to maintain a capital structure consistent with that approved by the PSCW. For more information on our approved capital structure, see Item 1. Business – C. Regulation.

The issuance of our securities is subject to the approval of the PSCW. Additionally, with respect to the public offering of securities, we file registration statements with the SEC under the Securities Act of 1933, as amended (1933 Act). The amounts of securities

2023 Form 10-K 45 Wisconsin Electric Power Company

authorized by the PSCW, as well as the securities registered under the 1933 Act, are closely monitored and appropriate filings are made to ensure flexibility in the capital markets.

At December 31, 2023, our current liabilities exceeded our current assets by $279.6 million. We do not expect this to have any impact on our liquidity as we currently believe that our cash and cash equivalents, our available capacity under our existing revolving credit facility, cash generated from ongoing operations, and access to the capital markets are adequate to meet our short-term and long-term cash requirements.

See Note 13, Short-Term Debt and Lines of Credit, and Note 14, Long-Term Debt, for more information about our credit facility and debt securities.

Investments in Outside Trusts

We maintain investments in outside trusts to fund the obligation to provide pension and certain OPEB benefits to current and future retirees. As of December 31, 2023, these trusts had investments of approximately $1.1 billion, consisting of fixed income and equity securities, that are subject to the volatility of the stock market and interest rates. The performance of existing plan assets, long-term discount rates, changes in assumptions, and other factors could affect our future contributions to the plans, our financial position if our accumulated benefit obligation exceeds the fair value of the plan assets, and future results of operations related to changes in pension and OPEB expense and the assumed rate of return. For additional information, see Note 19, Employee Benefits.

Debt Covenants

Our credit facility contains financial covenants that we must satisfy, including a debt to capitalization ratio. At December 31, 2023, we were in compliance with all such covenants. We expect to be in compliance with all such debt covenants for the foreseeable future. See Note 13, Short-Term Debt and Lines of Credit, and Note 14, Long-Term Debt, for more information.

Credit Rating Risk

Cash collateral postings and prepayments made with external parties, including postings related to exchange-traded contracts, and cash collateral posted by external parties were immaterial as of December 31, 2023. From time to time, we may enter into commodity contracts that could require collateral or a termination payment in the event of a credit rating change to below BBB- at S&P Global Ratings, a division of S&P Global Inc., and/or Baa3 at Moody’s Investors Service, Inc. If we had a sub-investment grade credit rating at December 31, 2023, we could have been required to post $100 million of additional collateral or other assurances pursuant to the terms of a PPA. We also have other commodity contracts that, in the event of a credit rating downgrade, could result in a reduction of our unsecured credit granted by counterparties.

In addition, access to capital markets at a reasonable cost is determined in large part by credit quality. Any credit ratings downgrade could impact our ability to access capital markets.

Subject to other factors affecting the credit markets as a whole, we believe our current ratings should provide a significant degree of flexibility in obtaining funds on competitive terms. However, these security ratings reflect the views of the rating agency only. An explanation of the significance of these ratings may be obtained from the rating agency. Such ratings are not a recommendation to buy, sell, or hold securities. Any rating can be revised upward or downward or withdrawn at any time by a rating agency.

FACTORS AFFECTING RESULTS, LIQUIDITY, AND CAPITAL RESOURCES

Competitive Markets

Electric Utility Industry

The FERC supports large RTOs, which directly impacts the structure of the wholesale electric market. Due to the FERC's support of RTOs, MISO uses the MISO Energy Markets to carry out its operations, including the use of LMPs to value electric transmission congestion and losses. Increased competition in the retail and wholesale markets, which may result from restructuring efforts, could have a significant and adverse financial impact on us.

2023 Form 10-K 46 Wisconsin Electric Power Company

Electric utility revenues in Wisconsin are regulated by the PSCW. The PSCW continues to maintain the position that the question of whether to implement electric retail competition in Wisconsin should ultimately be decided by the Wisconsin legislature. No such legislation has been introduced in Wisconsin to date, and it is uncertain when, if at all, retail choice might be implemented in Wisconsin.

Natural Gas Utility Industry

We offer both natural gas transportation service and interruptible natural gas sales to enable customers to better manage their energy costs. Customers continue to switch between firm system supply, interruptible system supply, and transportation service each year as the economics and service options change.

Due to the PSCW's previous proceedings on natural gas industry regulation in a competitive environment, the PSCW currently provides all Wisconsin customer classes with competitive markets the option to choose a third-party natural gas supplier. All of our Wisconsin non-residential customer classes have competitive market choices and, therefore, can purchase natural gas directly from either a third-party supplier or us. Since third-party suppliers can be used in Wisconsin, the PSCW has also adopted standards for transactions between a utility and its natural gas marketing affiliates.

We offer natural gas transportation services to our customers that elect to purchase natural gas directly from a third-party supplier. Since these transportation customers continue to use our distribution systems to transport natural gas to their facilities, we earn distribution revenues from them. As such, the loss of revenue associated with the cost of natural gas that our transportation customers purchase from third-party suppliers has little impact on our net income, as it is substantially offset by an equal reduction to natural gas costs.

We are currently unable to predict the impact, if any, of potential future industry restructuring on our results of operations or financial position.

Regulatory, Legislative, and Legal Matters

Regulatory Recovery

We account for our regulated operations in accordance with accounting guidance under the Regulated Operations Topic of the FASB ASC. Our rates are determined by the PSCW and the FERC. See Item 1. Business – C. Regulation for more information on these commissions. See Note 24, Regulatory Environment, for additional information regarding recent rate proceedings and orders.

Regulated entities are allowed to defer certain costs that would otherwise be charged to expense if the regulated entity believes the recovery of those costs is probable. We record regulatory assets pursuant to generic and/or specific orders issued by our regulators. Recovery of the deferred costs in future rates is subject to the review and approval by our regulators. We assume the risks and benefits of ultimate recovery of these items in future rates. If the recovery of the deferred costs is not approved by our regulators, the costs would be charged to income in the current period. Regulators can impose liabilities on a prospective basis for amounts previously collected from customers and for amounts that are expected to be refunded to customers. We record these items as regulatory liabilities. See Note 7, Regulatory Assets and Liabilities, for more information on our regulatory assets and liabilities.

Petitions Before PSCW Regarding Third-Party Financed Distributed Energy Resources

In May 2022, two petitions were filed with the PSCW requesting a declaratory ruling that the owner of a third-party financed DER is not a "public utility" as defined under Wisconsin law and, therefore, is not subject to the PSCW’s jurisdiction under any statute or rule regulating public utilities. The parties that filed the petitions provide financing to their customers for installation of DERs (including solar panels and energy storage) on the customer’s property. A DER is connected to the host customer’s utility meter and is used for the customer’s energy needs. It may also be connected to the grid for distribution.

In July 2022, the PSCW found that the specific facts and circumstances merited the opening of a docket for each petition to consider whether to grant all or part of the requested declaratory ruling.

In December 2022, the PSCW granted one petitioner’s request for a declaratory ruling, finding that the owner of the third-party financed DER at issue in the petitioner’s brief is not a public utility under Wisconsin law. The ruling was limited to the specific facts and circumstances of the lease presented in that petition. A petition by the WUA to reopen or rehear the case expired without

2023 Form 10-K 47 Wisconsin Electric Power Company

action by the PSCW. The WUA has filed an appeal which is pending consideration by the circuit court. The second petition was denied. Although the finding in the first petition was limited to the specific facts and circumstances of the lease presented in that petition, similar findings or a broader policy position could adversely impact our business operations.

Uyghur Forced Labor Prevention Act

The CBP issued a WRO in June 2021, applicable to certain silica-based products originating from the Xinjiang Uyghur Autonomous Region of China (Xinjiang), such as polysilicon, included in the manufacturing of solar panels. In June 2022, the WRO was superseded by the implementation of the UFLPA. The UFLPA establishes a rebuttable presumption that any imports wholly or partially manufactured in Xinjiang are prohibited from entering the United States. While our suppliers were able to provide the CBP sufficient documentation to meet WRO compliance requirements, and we expect the same will be true for UFLPA purposes, we cannot currently predict what, if any, long-term impact the UFLPA will have on the overall supply of solar panels into the United States and whether we will experience any further impacts to the timing and cost of our solar projects included in WEC Energy Group's long-term capital plan.

United States Department of Commerce Complaints

In February 2022, a California based company filed a petition (Antidumping and Countervailing Duties) with the DOC seeking to impose new tariffs on solar panels and cells imported from multiple countries, including Malaysia, Vietnam, Thailand, and Cambodia. The petitioners claimed that Chinese solar manufacturers are shifting products to these countries to avoid the tariffs required on products imported from China and requested that the DOC conduct a country-wide inquiry into each of the four countries. After investigation, in December 2022, the DOC announced its preliminary determination that certain companies are circumventing anti-dumping and countervailing duty orders on solar cells and modules from China.

In August 2023, the DOC issued its final decision, substantially affirming its preliminary determination that circumvention was occurring in each of the four Southeast Asian countries noted above. In its decision, the DOC affirmed that the Biden Administration’s current 24-month tariff moratorium will remain in effect until June 6, 2024, subject to certain use and installation requirements, at which time tariffs are expected to resume. In December 2023, two U.S. solar manufacturers filed a challenge to this moratorium in the United States Court of International Trade.

The Biden Administration also invoked the Defense Production Act to accelerate the production of solar panels in the U.S.; however, the DOC’s ruling may have an adverse impact on the solar industry overall. Additionally, the Biden Administration's actions did not address whether WROs applied to panels under previous complaints would be affected. At this time, we do not expect this final ruling to have a material impact on our results of operations.

Infrastructure Investment and Jobs Act

In November 2021, President Biden signed into law the Infrastructure Investment and Jobs Act, which provides for approximately $1.2 trillion of federal spending over a five year period, including approximately $85 billion for investments in power, utilities, and renewables infrastructure across the United States. We expect funding from this Act will support the work we are doing to reduce GHG emissions, increase EV charging, and strengthen and protect the energy grid. Funding in the Act should also help to expand emerging technologies, like hydrogen and carbon management, as we continue the transition to a clean energy future. We believe the Infrastructure Investment and Jobs Act will accelerate investment in projects that will help us meet our net zero emission goals to the benefit of our customers, the communities we serve, and our company.

Inflation Reduction Act

In August 2022, President Biden signed into law the IRA, which provides for $258 billion in energy-related provisions over a 10-year period. The provisions of the IRA are intended to, among other things, lower gasoline and electricity prices, incentivize domestic clean energy investment, manufacturing, and production, and promote reductions in carbon emissions. We believe that we and our customers can benefit from the IRA’s provisions that extend tax benefits for renewable technologies, increase or restore higher rates for PTCs, add an option to claim PTCs for solar projects, expand qualified ITC facilities to include standalone energy storage, and its provision to allow companies to transfer tax credits generated from renewable projects. Under this new IRA transferability option, we entered into a sales agreement in September 2023 to sell substantially all of our 2023 PTCs to a third party. See Note 1(n), Income Taxes, for more information about the impact of these sales. The IRA also implements a 15% corporate alternative minimum tax and a 1% excise tax on stock repurchases. Although significant regulatory guidance is expected on the tax provisions in the IRA,

2023 Form 10-K 48 Wisconsin Electric Power Company

we currently believe the provisions on alternative minimum tax and stock repurchases will not have a material impact on us. Overall, we believe the IRA will help reduce our cost of investing in projects that will support our commitment to reduce emissions and provide customers affordable, reliable, and clean energy over the longer term.

Environmental Matters

See Note 22, Commitments and Contingencies, for a discussion of certain environmental matters affecting us, including rules and regulations relating to air quality, water quality, and land quality.

Market Risks and Other Significant Risks

We are exposed to market and other significant risks as a result of the nature of our businesses and the environments in which those businesses operate. These risks, described in further detail below, include but are not limited to:

Commodity Costs

In the normal course of providing energy, we are subject to market fluctuations in the costs of coal, natural gas, purchased power, and fuel oil used in the delivery of coal. We manage our fuel and natural gas supply costs through a portfolio of short and long-term procurement contracts with various suppliers for the purchase of coal, natural gas, and fuel oil. In addition, we manage the risk of price volatility through natural gas and electric hedging programs.

Embedded within our rates are amounts to recover fuel, natural gas, and purchased power costs. We have recovery mechanisms in place that generally allow us to recover or refund all or a portion of the changes in prudently incurred fuel, natural gas, and purchased power costs from rate case-approved amounts. See Item 1. Business – C. Regulation for more information on these mechanisms.

Higher commodity costs can increase our working capital requirements, result in higher gross receipts taxes, and lead to increased energy efficiency investments by our customers to reduce utility usage and/or fuel substitution. Higher commodity costs combined with slower economic conditions also expose us to greater risks of accounts receivable write-offs as more customers are unable to pay their bills. See Note 6, Credit Losses, for more information on our mechanism that allows for cost recovery or refund of uncollectible expense.

Weather

Our utility rates are based upon estimated normal temperatures. Our electric utility margins are unfavorably sensitive to below normal temperatures during the summer cooling season and, to some extent, to above normal temperatures during the winter heating season. Our natural gas utility margins are unfavorably sensitive to above normal temperatures during the winter heating season. A summary of actual weather information in our service territory during 2023 and 2022, as measured by degree days, may be found in Results of Operations.

Interest Rates

We are exposed to interest rate risk resulting from our short-term borrowings and projected near-term debt financing needs. We manage exposure to interest rate risk by limiting the amount of our variable rate obligations and continually monitoring the effects of market changes on interest rates. When it is advantageous to do so, we enter into long-term fixed rate debt.

Based on our variable rate debt outstanding at December 31, 2023 and 2022, a hypothetical increase in market interest rates of one percentage point would have increased annual interest expense by $3.6 million and $4.6 million in 2023 and 2022, respectively. This sensitivity analysis was performed assuming a constant level of variable rate debt during the period and an immediate increase in interest rates, with no other changes for the remainder of the period.

Marketable Securities Return

We use various trusts to fund our pension and OPEB obligations. These trusts invest in debt and equity securities. Changes in the market prices of these assets can affect future pension and OPEB expenses. Additionally, future contributions can also be affected by

2023 Form 10-K 49 Wisconsin Electric Power Company

the investment returns on trust fund assets. The financial risks associated with investment returns are mitigated through the requirement that we implement escrow accounting treatment for pension and OPEB costs in 2023 and 2024, as required by the December 2022 rate order issued by the PSCW. See Note 24, Regulatory Environment, for more information on our 2023 and 2024 rates.

The fair value of our trust fund assets and expected long-term returns were approximately:

(in millions)	As of December 31, 2023		Expected Return on Assets in 2024
Pension trust funds	$	932.2	6.50	%
OPEB trust funds	$	172.8	6.50	%

Fiduciary oversight of the pension and OPEB trust fund investments is the responsibility of an Investment Trust Policy Committee. The Committee works with external actuaries and investment consultants on an ongoing basis to establish and monitor investment strategies and target asset allocations. Forecasted cash flows for plan liabilities are regularly updated based on annual valuation results. Target asset allocations are determined utilizing projected benefit payment cash flows and risk analyses of appropriate investments. The targeted asset allocations are intended to reduce risk, provide long-term financial stability for the plans, and maintain funded levels which meet long-term plan obligations while preserving sufficient liquidity for near-term benefit payments. Investment strategies utilize a wide diversification of asset types and qualified external investment managers.

WEC Energy Group consults with its investment advisors on an annual basis to help it forecast expected long-term returns on plan assets by reviewing actual historical returns and calculating expected total trust returns using the weighted-average of long-term market returns for each of the major target asset categories utilized in the funds.

Economic Conditions

Our service territories are within the state of Wisconsin. As such, we are exposed to market risks in the regional Midwest economy. In addition, any economic downturn or disruption of national or international markets could adversely affect the financial condition of our customers and demand for their products, which could affect their demand for our products.

Inflation and Supply Chain Disruptions

We continue to monitor the impact of inflation and supply chain disruptions. We monitor the costs of medical plans, fuel, transmission access, construction costs, regulatory and environmental compliance costs, and other costs in order to minimize inflationary effects in future years, to the extent possible, through pricing strategies, productivity improvements, and cost reductions. We monitor the global supply chain, and related disruptions, in order to ensure we are able to procure the necessary materials and other resources necessary to both maintain our energy services in a safe and reliable manner and to grow our infrastructure in accordance with WEC Energy Group's capital plan, which includes us. For additional information concerning risks related to inflation and supply chain disruptions, see the four risk factors below.

•Item 1A. Risk Factors – Risks Related to the Operation of Our Business – Public health crises, including epidemics and pandemics, could adversely affect our business functions, financial condition, liquidity, and results of operations.

•Item 1A. Risk Factors – Risks Related to the Operation of Our Business – Our operations and corporate strategy may be adversely affected by supply chain disruptions and inflation.

•Item 1A. Risk Factors – Risks Related to the Operation of Our Business – We are actively involved with multiple significant capital projects, which are subject to a number of risks and uncertainties that could adversely affect project costs and completion of construction projects.

•Item 1A. Risk Factors – Risks Related to Economic and Market Volatility – Fluctuating commodity prices could negatively impact our operations.

For additional information concerning risk factors, including market risks, see the Cautionary Statement Regarding Forward-Looking Information at the beginning of this report and Item 1A. Risk Factors.

2023 Form 10-K 50 Wisconsin Electric Power Company

Critical Accounting Policies and Estimates

The preparation of financial statements in compliance with GAAP requires the application of accounting policies, as well as the use of estimates, assumptions, and judgments that could have a material impact on our financial statements and related disclosures. Judgments regarding future events may include the likelihood of success of particular projects, legal and regulatory challenges, and anticipated recovery of costs. Actual results may differ significantly from estimated amounts based on varying assumptions.

Our significant accounting policies are described in Note 1, Summary of Significant Accounting Policies. The following is a list of accounting policies and estimates that require management's most difficult, subjective, or complex judgments and may change in subsequent periods.

Regulatory Accounting

Our utility operations follow the guidance under the Regulated Operations Topic of the FASB ASC (Topic 980). Our financial statements reflect the effects of the ratemaking principles followed by the jurisdictions regulating us. Certain items that would otherwise be immediately recognized as revenues and expenses are deferred as regulatory assets and regulatory liabilities for future recovery or refund to customers, as authorized by our regulators.

Future recovery of regulatory assets, including the timeliness of recovery and our ability to earn a reasonable return, is not assured and is generally subject to review by regulators in rate proceedings for matters such as prudence and reasonableness. Once approved, the regulatory assets and liabilities are amortized into earnings over the rate recovery or refund period. If recovery or refund of costs is not approved or is no longer considered probable, these regulatory assets or liabilities are recognized in current period earnings. Management regularly assesses whether these regulatory assets and liabilities are probable of future recovery or refund by considering factors such as changes in the regulatory environment, earnings from our electric and natural gas utility operations, rate orders issued by our regulators, historical decisions by our regulators regarding regulatory assets and liabilities, and the status of any pending or potential deregulation legislation.

The application of the Regulated Operations Topic of the FASB ASC would be discontinued if all or a separable portion of our utility operations no longer met the criteria for application. Our regulatory assets and liabilities would be written off to income as an unusual or infrequently occurring item in the period in which discontinuation occurred. See Note 7, Regulatory Assets and Liabilities, for more information on our regulatory assets and liabilities.

Long-Lived Assets

In accordance with ASC 980-360, Regulated Operations – Property, Plant, and Equipment, we periodically assess the recoverability of certain long-lived assets when events or changes in circumstances indicate that the carrying amount of those long-lived assets may not be recoverable. Examples of events or changes in circumstances include, but are not limited to, a significant decrease in the market price, a significant change in use, a regulatory decision related to recovery of assets from customers, adverse legal factors or a change in business climate, operating or cash flow losses, or an expectation that the asset might be sold or abandoned. See Note 1(j), Asset Impairment, for our policy on accounting for abandonments and recently completed plant subject to disallowance.

Performing an impairment evaluation involves a significant degree of estimation and judgment by management in areas such as identifying circumstances that indicate an impairment may exist, identifying and grouping affected assets, and developing the undiscounted future cash flows. An impairment loss is measured as the excess of the carrying amount of the asset in comparison to the fair value of the asset. The fair value of the asset is assessed using various methods, including internally developed discounted cash flow analysis, expected recovery of regulated assets, and analysis from outside advisors.

See Note 8, Property, Plant, and Equipment, for more information on our generating units probable of being retired. See Note 7, Regulatory Assets and Liabilities, and Note 24, Regulatory Environment, for more information on our retired generating units, including various approvals we received from the FERC and the PSCW.

Pension and Other Postretirement Employee Benefits

The costs of providing non-contributory defined pension benefits and OPEB, described in Note 19, Employee Benefits, are dependent upon numerous factors resulting from actual plan experience and assumptions of future experience.

2023 Form 10-K 51 Wisconsin Electric Power Company

Pension and OPEB costs are impacted by actual employee demographics (including age, compensation levels, and employment periods), the level of contributions made to the plans, and earnings on plan assets. Pension and OPEB costs may also be significantly affected by changes in key actuarial assumptions, including anticipated rates of return on plan assets, mortality and discount rates, and expected health care cost trends. Changes made to the plan provisions may also impact current and future pension and OPEB costs.

Pension and OPEB plan assets are primarily made up of equity and fixed income investments. Fluctuations in actual equity and fixed income market returns, as well as changes in general interest rates, may result in increased or decreased benefit costs in future periods. Changes in benefit costs are mitigated through the requirement that we implement escrow accounting treatment for pension and OPEB costs in 2023 and 2024, as required by the December 2022 rate order issued by the PSCW. See Note 24, Regulatory Environment, for more information on our 2023 and 2024 rates.

The following table shows how a given change in certain actuarial assumptions would impact the projected benefit obligation and the reported net periodic pension cost (including amounts capitalized to our balance sheets). Each factor below reflects an evaluation of the change based on a change in that assumption only.

Actuarial Assumption (in millions, except percentages)	Percentage-Point Change in Assumption	Impact on Projected Benefit Obligation		Impact on 2023 Pension Cost
Discount rate	(0.5)	$	34.2	$	2.3
Discount rate	0.5	(32.9)		(1.8)
Rate of return on plan assets	(0.5)	N/A		5.0
Rate of return on plan assets	0.5	N/A		(5.0)

The following table shows how a given change in certain actuarial assumptions would impact the accumulated OPEB obligation and the reported net periodic OPEB cost (including amounts capitalized to our balance sheets). Each factor below reflects an evaluation of the change based on a change in that assumption only.

Actuarial Assumption (in millions, except percentages)	Percentage-Point Change in Assumption	Impact on Postretirement Benefit Obligation		Impact on 2023 Postretirement Benefit Cost
Discount rate	(0.5)	$	8.7	$	1.1
Discount rate	0.5	(8.2)		(1.0)
Health care cost trend rate	(0.5)	(4.0)		(0.9)
Health care cost trend rate	0.5	4.6		1.1
Rate of return on plan assets	(0.5)	N/A		1.0
Rate of return on plan assets	0.5	N/A		(1.0)

The discount rates are selected based on hypothetical bond portfolios consisting of noncallable, high-quality corporate bonds across the full maturity spectrum. From the hypothetical bond portfolios, a single rate is determined that equates the market value of the bonds purchased to the discounted value of the plans' expected future benefit payments.

We establish our expected return on assets based on consideration of historical and projected asset class returns, as well as the target allocations of the benefit trust portfolios. The assumed long-term rate of return on pension plan assets was 6.50% in 2023 and 6.75% in 2022 and 2021. The actual rate of return on pension plan assets, net of fees, was 8.09%, (11.36)%, and 8.82% in 2023, 2022, and 2021, respectively.

In selecting assumed health care cost trend rates, past performance and forecasts of health care costs are considered. For more information on health care cost trend rates and a table showing future payments that we expect to make for our pension and OPEB, see Note 19, Employee Benefits.

Unbilled Revenues

We record utility operating revenues when energy is delivered to our customers. However, the determination of energy sales to individual customers is based upon the reading of their meters, which occurs on a systematic basis throughout the month. At the end of each month, amounts of energy delivered to customers since the date of their last meter reading are estimated and corresponding unbilled revenues are calculated.

2023 Form 10-K 52 Wisconsin Electric Power Company

Unbilled revenues are estimated each month based upon actual generation and throughput volumes, recorded sales, estimated customer usage by class, weather factors, estimated line losses, and applicable customer rates. Energy demand for the unbilled period or changes in rate mix due to fluctuations in usage patterns of customer classes could impact the accuracy of the unbilled revenue estimate. Total unbilled utility revenues were $176.1 million and $201.5 million as of December 31, 2023 and 2022, respectively. The changes in unbilled revenues are primarily due to changes in the cost of natural gas, weather, and customer rates.

Income Tax Expense

Significant management judgment is required in determining our provision for income taxes, deferred income tax assets and liabilities, the liability for unrecognized tax benefits, and any valuation allowance recorded against deferred income tax assets. The assumptions involved are supported by historical data, reasonable projections, and interpretations of applicable tax laws and regulations across multiple taxing jurisdictions. Significant changes in these assumptions could have a material impact on our financial condition and results of operations. See Note 1(n), Income Taxes, and Note 16, Income Taxes, for a discussion of accounting for income taxes.

We are required to estimate income taxes for each of our applicable tax jurisdictions as part of the process of preparing consolidated financial statements. This process involves estimating current income tax liabilities together with assessing temporary differences resulting from differing treatment of items, such as depreciation, for income tax and accounting purposes. These differences result in deferred income tax assets and liabilities, which are included within our balance sheets. We also assess the likelihood that our deferred income tax assets will be recovered through future taxable income. To the extent we believe that realization is not likely, we establish a valuation allowance, which is offset by an adjustment to income tax expense in our income statements.

Uncertainty associated with the application of tax statutes and regulations, the outcomes of tax audits and appeals, changes in income tax law, enacted tax rates or amounts subject to income tax, and changes in the regulatory treatment of any tax reform benefits requires that judgments and estimates be made in the accrual process and in the calculation of effective tax rates. Only income tax benefits that meet the "more likely than not" recognition threshold may be recognized or continue to be recognized. Unrecognized tax benefits are re-evaluated quarterly and changes are recorded based on new information, including the issuance of relevant guidance by the courts or tax authorities and developments occurring in the examinations of our tax returns.

We expect our 2024 annual effective tax rate to be between 21.5% and 22.5%. Our effective tax rate calculations are revised every quarter based on the best available year-end tax assumptions, adjusted in the following year after returns are filed. Tax accrual estimates are trued-up to the actual amounts claimed on the tax returns and further adjusted after examinations by taxing authorities, as needed.

ITEM 7A. QUANTITATIVE AND QUALITATIVE DISCLOSURES ABOUT MARKET RISK

See Item 7. Management's Discussion and Analysis of Financial Condition and Results of Operations – Factors Affecting Results, Liquidity, and Capital Resources – Market Risks and Other Significant Risks, as well as Note 1(o), Fair Value Measurements, Note 1(p), Derivative Instruments, and Note 1(q), Guarantees, for information concerning potential market risks to which we are exposed.

2023 Form 10-K 53 Wisconsin Electric Power Company

ITEM 8. FINANCIAL STATEMENTS AND SUPPLEMENTARY DATA

A. REPORT OF INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM

To the shareholders and the Board of Directors of Wisconsin Electric Power Company

Opinion on the Financial Statements

We have audited the accompanying consolidated balance sheets of Wisconsin Electric Power Company and subsidiary (the "Company") as of December 31, 2023 and 2022, the related consolidated statements of income, equity, and cash flows, for each of the three years in the period ended December 31, 2023, and the related notes and the schedule listed in the Index at Item 15 (collectively referred to as the "financial statements"). In our opinion, the financial statements present fairly, in all material respects, the financial position of the Company as of December 31, 2023 and 2022, and the results of its operations and its cash flows for each of the three years in the period ended December 31, 2023, in conformity with accounting principles generally accepted in the United States of America.

Basis for Opinion

These financial statements are the responsibility of the Company's management. Our responsibility is to express an opinion on the Company's financial statements based on our audits. We are a public accounting firm registered with the Public Company Accounting Oversight Board (United States) (PCAOB) and are required to be independent with respect to the Company in accordance with the U.S. federal securities laws and the applicable rules and regulations of the Securities and Exchange Commission and the PCAOB.

We conducted our audits in accordance with the standards of the PCAOB. Those standards require that we plan and perform the audit to obtain reasonable assurance about whether the financial statements are free of material misstatement, whether due to error or fraud. The Company is not required to have, nor were we engaged to perform, an audit of its internal control over financial reporting. As part of our audits, we are required to obtain an understanding of internal control over financial reporting but not for the purpose of expressing an opinion on the effectiveness of the Company’s internal control over financial reporting. Accordingly, we express no such opinion.

Our audits included performing procedures to assess the risks of material misstatement of the financial statements, whether due to error or fraud, and performing procedures that respond to those risks. Such procedures included examining, on a test basis, evidence regarding the amounts and disclosures in the financial statements. Our audits also included evaluating the accounting principles used and significant estimates made by management, as well as evaluating the overall presentation of the financial statements. We believe that our audits provide a reasonable basis for our opinion.

Critical Audit Matter

The critical audit matter communicated below is a matter arising from the current-period audit of the financial statements that was communicated or required to be communicated to the audit committee and that (1) relates to accounts or disclosures that are material to the financial statements and (2) involved our especially challenging, subjective, or complex judgments. The communication of critical audit matters does not alter in any way our opinion on the financial statements, taken as a whole, and we are not, by communicating the critical audit matter below, providing a separate opinion on the critical audit matter or on the accounts or disclosures to which it relates.

Regulatory Assets and Liabilities - Impact of rate regulation on financial statements — Refer to Notes 7 and 24 to the financial statements

Critical Audit Matter Description

The Company is subject to regulation by state and federal regulatory bodies (collectively the “Commissions”) which have jurisdiction with respect to the rates of electric and gas distribution. Management has determined the Company meets the requirements under accounting principles generally accepted in the United States of America to prepare its financial statements applying the Regulated Operations Topic of the Financial Accounting Standards Board’s Accounting Standard Codification.

2023 Form 10-K 54 Wisconsin Electric Power Company

Rates are determined and approved in regulatory proceedings based on an analysis of the Company’s costs to provide utility service and a return on, and recovery of, the Company’s investment in the utility business. Current and future regulatory decisions can have an impact on the recovery of costs, the rate of return earned on investment, and the timing and amount of assets to be recovered through rates. The Commissions’ regulation of rates is premised on the full recovery of prudently incurred costs and a reasonable rate of return on invested capital. Certain items that would otherwise be immediately recognized as revenues and expenses are deferred as regulatory assets and regulatory liabilities for future recovery or refund to customers, as authorized by the Company’s regulators. While the Company has indicated it expects to recover costs from customers through regulated rates, there is a risk that the Commissions will not approve: (1) full recovery of the costs of providing utility service, (2) full recovery of all amounts invested in the utility business and a reasonable return on that investment or (3) timely recovery of costs incurred.

We identified the impact of rate regulation as a critical audit matter due to the significant judgments made by management to support its assertions about impacted account balances and disclosures and the subjectivity involved in assessing the impact of future regulatory orders on the financial statements. Management judgments include assessing the likelihood of (1) recovery in future rates of incurred costs and/or (2) a refund to customers. Auditing these judgments required specialized knowledge of accounting for rate regulation and the rate setting process due to its inherent complexities.

How the Critical Audit Matter Was Addressed in the Audit

Our audit procedures related to the impact of rate regulation on certain assets and liabilities included the following, among others:

•We tested the effectiveness of management’s controls over regulatory assets and liabilities, including management’s controls over the identification of costs recorded as regulatory assets and liabilities and the monitoring and evaluation of regulatory developments that may affect the likelihood of recovering costs in future rates.

•We inquired of Company management and independently obtained and read: (1) relevant regulatory orders issued by the Commissions for the Company, (2) Company filings with the Commissions, (3) filings made by intervenors and (4) other publicly available information to assess the likelihood of recovery in future rates or of a future reduction in rates based on precedents of the Commissions’ treatment of similar costs under similar circumstances. To assess completeness, we evaluated the information obtained and compared it to management’s recorded regulatory asset and liability balances.

•For regulatory matters in process, we inspected the Company’s filings with the Commissions and the filings with the Commissions by intervenors that may impact the Company’s future rates, for any evidence that might contradict management’s assertions.

•We evaluated management’s analysis regarding probability of recovery for regulatory assets or refund or future reduction in rates for regulatory liabilities not yet addressed in a regulatory order to assess management’s assertion that amounts are probable of recovery or a future reduction in rates.

•We evaluated the Company’s disclosures related to the impacts of rate regulation, including the balances recorded and regulatory developments.

/s/DELOITTE & TOUCHE LLP

Milwaukee, Wisconsin

February 22, 2024

We have served as the Company's auditor since 2002.

2023 Form 10-K 55 Wisconsin Electric Power Company

B. CONSOLIDATED INCOME STATEMENTS

Year Ended December 31
(in millions)	2023		2022		2021
Operating revenues	$	4,045.0	$	4,070.3	$	3,664.5
Operating expenses
Cost of sales	1,451.4		1,693.3		1,341.1
Other operation and maintenance	931.1		831.7		898.4
Depreciation and amortization	525.0		479.7		457.9
Property and revenue taxes	115.3		125.6		98.4
Total operating expenses	3,022.8		3,130.3		2,795.8
Operating income	1,022.2		940.0		868.7
Other income, net	68.8		49.4		32.1
Interest expense	466.5		458.4		460.3
Other expense	(397.7)		(409.0)		(428.2)
Income before income taxes	624.5		531.0		440.5
Income tax expense	142.7		133.1		58.1
Net income	481.8		397.9		382.4
Preferred stock dividend requirements	1.2		1.2		1.2
Net income attributed to common shareholder	$	480.6	$	396.7	$	381.2

The accompanying Notes to Consolidated Financial Statements are an integral part of these financial statements.

2023 Form 10-K 56 Wisconsin Electric Power Company

C. CONSOLIDATED BALANCE SHEETS

At December 31
(in millions, except share and per share amounts)	2023		2022
Assets
Current assets
Cash and cash equivalents	$	6.1	$	6.1
Accounts receivable and unbilled revenues, net of reserves of $44.5 and $49.7, respectively	573.0		582.6
Accounts receivable from related parties	143.9		113.2
Materials, supplies, and inventories	310.6		292.9
Prepaid taxes	112.7		113.1
Other prepayments	26.7		25.6
Other	32.3		73.8
Current assets	1,205.3		1,207.3
Long-term assets
Property, plant, and equipment, net of accumulated depreciation and amortization of $5,779.2 and $5,450.3, respectively	11,585.5		10,718.6
Regulatory assets (December 31, 2023 and December 31, 2022 include $85.9 and $92.4, respectively, related to WEPCo Environmental Trust)	2,860.7		2,817.5
Pension and OPEB assets	71.0		143.3
Other	118.9		133.5
Long-term assets	14,636.1		13,812.9
Total assets	$	15,841.4	$	15,020.2
Liabilities and Equity
Current liabilities
Short-term debt	$	360.8	$	460.7
Current portion of long-term debt (December 31, 2023 and December 31, 2022 include $9.0 and $8.9, respectively, related to WEPCo Environmental Trust)	309.0		8.9
Current portion of finance lease obligations	87.8		112.3
Accounts payable	332.1		400.5
Accounts payable to related parties	193.8		179.4
Other	201.4		210.5
Current liabilities	1,484.9		1,372.3
Long-term liabilities
Long-term debt (December 31, 2023 and December 31, 2022 include $85.3 and $94.1, respectively, related to WEPCo Environmental Trust)	3,045.4		3,351.5
Finance lease obligations	2,752.2		2,702.3
Deferred income taxes	1,513.5		1,467.3
Regulatory liabilities	1,631.4		1,637.4
Other	330.5		322.2
Long-term liabilities	9,273.0		9,480.7
Commitments and contingencies (Note 22)
Common shareholder's equity
Common stock – $10 par value; 65,000,000 shares authorized; 33,289,327 shares outstanding	332.9		332.9
Additional paid in capital	2,552.4		1,746.8
Retained earnings	2,167.8		2,057.1
Common shareholder's equity	5,053.1		4,136.8
Preferred stock	30.4		30.4
Total liabilities and equity	$	15,841.4	$	15,020.2

The accompanying Notes to Consolidated Financial Statements are an integral part of these financial statements.

2023 Form 10-K 57 Wisconsin Electric Power Company

D. CONSOLIDATED STATEMENTS OF CASH FLOWS

Year Ended December 31
(in millions)	2023		2022		2021
Operating activities
Net income	$	481.8	$	397.9	$	382.4
Reconciliation to cash provided by operating activities
Depreciation and amortization	525.0		479.7		457.9
Deferred income taxes and ITCs, net	20.7		54.6		(26.4)
Net change in transmission regulatory asset and liability	18.4		(64.2)		2.7
Change in –
Accounts receivable and unbilled revenues, net	(4.6)		(69.8)		(68.4)
Materials, supplies, and inventories	(12.8)		(46.5)		(26.9)
Collateral on deposit	20.0		(40.9)		0.8
Other current assets	(4.8)		(16.1)		(0.9)
Accounts payable	(41.3)		14.5		85.5
Other current liabilities	(8.2)		28.8		(6.9)
Other, net	(55.1)		(101.0)		2.4
Net cash provided by operating activities	939.1		637.0		802.2
Investing activities
Capital expenditures	(1,094.6)		(930.4)		(813.3)
Acquisition of Whitewater	(38.0)		—		—
Acquisition of West Riverside	(95.3)		—		—
Proceeds from the sale of assets	24.3		1.6		1.4
Payments for ATC's construction costs that will be reimbursed	(16.5)		(19.2)		(2.6)
Proceeds from assets transferred to affiliates	—		—		10.7
Insurance proceeds received for property damage	0.5		41.0		—
Other, net	(7.7)		(7.0)		5.8
Net cash used in investing activities	(1,227.3)		(914.0)		(798.0)
Financing activities
Change in short-term debt	(99.9)		85.7		83.0
Issuance of long-term debt	—		500.0		418.8
Retirement of long-term debt	(8.9)		(8.8)		(304.1)
Payments for finance lease obligations	(77.0)		(73.6)		(67.5)
Equity contribution from parent	805.0		455.0		230.0
Payment of dividends to parent	(370.0)		(630.0)		(360.0)
Other, net	(1.2)		(6.6)		(8.6)
Net cash provided by (used in) financing activities	248.0		321.7		(8.4)
Net change in cash, cash equivalents, and restricted cash	(40.2)		44.7		(4.2)
Cash, cash equivalents, and restricted cash at beginning of year	47.7		3.0		7.2
Cash, cash equivalents, and restricted cash at end of year	$	7.5	$	47.7	$	3.0

The accompanying Notes to Consolidated Financial Statements are an integral part of these financial statements.

2023 Form 10-K 58 Wisconsin Electric Power Company

E. CONSOLIDATED STATEMENTS OF EQUITY

	Wisconsin Electric Power Company Common Shareholder's Equity
	Common Stock		Additional Paid In Capital		Retained Earnings		Total Common Shareholder's Equity		Preferred Stock		Total Equity
(in millions)
Balance at December 31, 2020	$	332.9	$	1,060.1	$	2,269.2	$	3,662.2	$	30.4	$	3,692.6
Net income attributed to common shareholder	—		—		381.2		381.2		—		381.2
Payment of dividends to parent	—		—		(360.0)		(360.0)		—		(360.0)
Equity contribution from parent	—		230.0		—		230.0		—		230.0
Stock-based compensation and other	—		0.8		0.1		0.9		—		0.9
Balance at December 31, 2021	$	332.9	$	1,290.9	$	2,290.5	$	3,914.3	$	30.4	$	3,944.7
Net income attributed to common shareholder	—		—		396.7		396.7		—		396.7
Payment of dividends to parent	—		—		(630.0)		(630.0)		—		(630.0)
Equity contribution from parent	—		455.0		—		455.0		—		455.0
Stock-based compensation and other	—		0.9		(0.1)		0.8		—		0.8
Balance at December 31, 2022	$	332.9	$	1,746.8	$	2,057.1	$	4,136.8	$	30.4	$	4,167.2
Net income attributed to common shareholder	—		—		480.6		480.6		—		480.6
Payment of dividends to parent	—		—		(370.0)		(370.0)		—		(370.0)
Equity contribution from parent	—		805.0		—		805.0		—		805.0
Stock-based compensation and other	—		0.6		0.1		0.7		—		0.7
Balance at December 31, 2023	$	332.9	$	2,552.4	$	2,167.8	$	5,053.1	$	30.4	$	5,083.5

The accompanying Notes to Consolidated Financial Statements are an integral part of these financial statements.

2023 Form 10-K 59 Wisconsin Electric Power Company

F. NOTES TO CONSOLIDATED FINANCIAL STATEMENTS

NOTE 1—SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES

(a) Nature of Operations—We are an electric, natural gas, and steam utility company that serves electric and natural gas customers in Wisconsin, and steam customers in metropolitan Milwaukee, Wisconsin. WEC Energy Group owns all of our outstanding common stock.

As used in these notes, the term "financial statements" refers to the consolidated financial statements. This includes the income statements, balance sheets, statements of cash flows, and statements of equity, unless otherwise noted. On our financial statements, we consolidate VIEs of which we are the primary beneficiary.

These financial statements reflect our proportionate interests in certain jointly owned utility facilities. See Note 9, Jointly Owned Utility Facilities, for more information.

(b) Basis of Presentation—We prepare our financial statements in conformity with GAAP. We make estimates and assumptions that affect the reported amounts of assets and liabilities, the disclosure of contingent assets and liabilities at the date of the financial statements, and the reported amounts of revenues and expenses during the reporting period. Actual results may differ from these estimates.

(c) Cash and Cash Equivalents—Cash and cash equivalents include marketable debt securities with an original maturity of three months or less.

(d) Operating Revenues—The following discussion includes our significant accounting policies related to operating revenues. For additional required disclosures on disaggregation of operating revenues, see Note 5, Operating Revenues.

Revenues from Contracts with Customers

Electric Utility Operating Revenues

Electricity sales to residential and commercial and industrial customers are generally accomplished through requirements contracts, which provide for the delivery of as much electricity as the customer needs. These contracts represent discrete deliveries of electricity and consist of one distinct performance obligation satisfied over time, as the electricity is delivered and consumed by the customer simultaneously. For our residential and commercial and industrial customers, our performance obligation is bundled to consist of both the sale and the delivery of the electric commodity.

The transaction price of the performance obligations for residential and commercial and industrial customers is valued using the rates, charges, terms, and conditions of service included in our tariffs, which have been approved by the PSCW. These rates often have a fixed component customer charge and a usage-based variable component charge. We recognize revenue for the fixed component customer charge monthly using a time-based output method. We recognize revenue for the usage-based variable component charge using an output method based on the quantity of electricity delivered each month. Our retail electric rates in Wisconsin include base amounts for fuel and purchased power costs, which also impact our revenues. The electric fuel rules set by the PSCW allow us to defer, for subsequent rate recovery or refund, under- or over-collections of actual fuel and purchased power costs beyond a 2% price variance from the costs included in the rates charged to customers. We monitor the deferral of under-collected costs to ensure that it does not cause us to earn a greater ROE than authorized by the PSCW. In addition, our residential tariffs include a mechanism for cost recovery or refund of uncollectible expense based on the difference between actual uncollectible write-offs and the amounts recovered in rates.

Wholesale customers who resell power can choose to either bundle capacity and electricity services together under one contract with a supplier or purchase capacity and electricity separately from multiple suppliers. Furthermore, wholesale customers can choose to have us provide generation to match the customer's load, similar to requirements contracts, or they can purchase specified quantities of electricity and capacity. Contracts with wholesale customers that include capacity bundled with the delivery of electricity contain two performance obligations, as capacity and electricity are often transacted separately in the marketplace at the wholesale level. When recognizing revenue associated with these contracts, the transaction price is allocated to each performance obligation based on its relative standalone selling price. Revenue is recognized as control of each individual component is transferred to the customer. Electricity is the primary product sold by our electric operations and represents a single performance

2023 Form 10-K 60 Wisconsin Electric Power Company

obligation satisfied over time through discrete deliveries to a customer. Revenue from electricity sales is generally recognized as units are produced and delivered to the customer within the production month. Capacity represents the reservation of an electric generating facility and conveys the ability to call on a plant to produce electricity when needed by the customer. The nature of our performance obligation as it relates to capacity is to stand ready to deliver power. This represents a single performance obligation transferred over time, which generally represents a monthly obligation. Accordingly, capacity revenue is recognized on a monthly basis.

The transaction price of the performance obligations for wholesale customers is valued using the rates, charges, terms, and conditions of service, which have been approved by the FERC. These wholesale rates include recovery of fuel and purchased power costs from customers on a one-for-one basis. For the majority of our wholesale customers, the price billed for energy and capacity is a formula-based rate. Formula-based rates initially set a customer's current year rates based on the previous year’s expenses. This is a predetermined formula derived from the utility’s costs and a reasonable rate of return. Because these rates are eventually trued up to reflect actual current-year costs, they represent a form of variable consideration in certain circumstances. The variable consideration is estimated and recognized over time as wholesale customers receive and consume the capacity and electricity services.

We are an active participant in the MISO Energy Markets, where we bid our generation into the Day Ahead and Real Time markets and procure electricity for our retail and wholesale customers at prices determined by the MISO Energy Markets. Purchase and sale transactions are recorded using settlement information provided by MISO. These purchase and sale transactions are accounted for on a net hourly position. Net purchases in a single hour are recorded as purchased power in cost of sales and net sales in a single hour are recorded as resale revenues on our income statements. For resale revenues, our performance obligation is created only when electricity is sold into the MISO Energy Markets.

For all of our customers, consistent with the timing of when we recognize revenue, customer billings generally occur on a monthly basis, with payments typically due in full within 30 days.

Natural Gas Utility Operating Revenues

We recognize natural gas utility operating revenues under requirements contracts with residential, commercial and industrial, and transportation customers served under our tariffs. Tariffs provide our customers with the standard terms and conditions, including rates, related to the services offered. Requirements contracts provide for the delivery of as much natural gas as the customer needs. These requirements contracts represent discrete deliveries of natural gas and constitute a single performance obligation satisfied over time. Our performance obligation is both created and satisfied with the transfer of control of natural gas upon delivery to the customer. For most of our customers, natural gas is delivered and consumed by the customer simultaneously. A performance obligation can be bundled to consist of both the sale and the delivery of the natural gas commodity. In Wisconsin, our customers can purchase the commodity from a third party. In this case, the performance obligation only includes the delivery of the natural gas to the customer.

The transaction price of the performance obligations for our natural gas customers is valued using the rates, charges, terms, and conditions of service included in our tariffs, which have been approved by the PSCW. These rates often have a fixed component customer charge and a usage-based variable component charge. We recognize revenue for the fixed component customer charge monthly using a time-based output method. We recognize revenue for the usage-based variable component charge using an output method based on natural gas delivered each month.

Our tariffs include various rate mechanisms that allow us to recover or refund changes in prudently incurred costs from rate case-approved amounts. Our rates include a one-for-one recovery mechanism for natural gas commodity costs. Under normal circumstances, we defer any difference between actual natural gas costs incurred and costs recovered through rates as a current asset or liability. The deferred balance is returned to or recovered from customers at intervals throughout the year. However, as a result of the extreme weather in the Midwest in February 2021, the cost of gas purchased for our natural gas customers was temporarily driven significantly higher than our normal winter weather expectations. See Note 24, Regulatory Environment, for more information on the recovery of these high natural gas costs.

In addition, our residential tariffs include a mechanism for cost recovery or refund of uncollectible expense based on the difference between actual uncollectible write-offs and the amounts recovered in rates.

Consistent with the timing of when we recognize revenue, customer billings generally occur on a monthly basis, with payments typically due in full within 30 days.

2023 Form 10-K 61 Wisconsin Electric Power Company

Other Operating Revenues

Alternative Revenues

Alternative revenues are created from programs authorized by regulators that allow us to record additional revenues by adjusting rates in the future, usually as a surcharge applied to future billings, in response to past activities or completed events. We record alternative revenues when the regulator-specified conditions for recognition have been met. We reverse these alternative revenues as the customer is billed, at which time this revenue is presented as revenues from contracts with customers.

Our only alternative revenue program relates to the wholesale electric service that we provide to customers under market-based rates and FERC formula rates. The customer is charged a base rate each year based upon a formula using prior year actual costs and customer demand. A true-up is calculated based on the difference between the amount billed to customers for the demand component of their rates and what the actual cost of service was for the year. The true-up can result in an amount that we will recover from or refund to the customer. We consider the true-up portion of the wholesale electric revenues to be alternative revenues.

(e) Credit Losses—The following discussion includes our significant accounting policies related to credit losses. For additional required disclosures on credit losses, see Note 6, Credit Losses.

Our exposure to credit losses is related to our accounts receivable and unbilled revenue balances, which are generated from the sale of electricity and natural gas by our regulated utility operations. Our regulated utility operations are included in our utility segment. No accounts receivable and unbilled revenue balances were reported in the other segment at December 31, 2023 and 2022.

We evaluate the collectability of our accounts receivable and unbilled revenue balances considering a combination of factors. For some of our larger customers and also in circumstances where we become aware of a specific customer's inability to meet its financial obligations to us, we record a specific allowance for credit losses against amounts due in order to reduce the net recognized receivable to the amount we reasonably believe will be collected. For all other customers, we use the accounts receivable aging method to calculate an allowance for credit losses. Using this method, we classify accounts receivable into different aging buckets and calculate a reserve percentage for each aging bucket based upon historical loss rates. The calculated reserve percentages are updated on at least an annual basis, in order to ensure recent macroeconomic, political, and regulatory trends are captured in the calculation, to the extent possible. Risks identified that we do not believe are reflected in the calculated reserve percentages, are assessed on a quarterly basis to determine whether further adjustments are required.

We monitor our ongoing credit exposure through active review of counterparty accounts receivable balances against contract terms and due dates. Our activities include timely account reconciliation, dispute resolution and payment confirmation. To the extent possible, we work with customers with past due balances to negotiate payment plans, but will disconnect customers for non-payment as allowed by the PSCW, if necessary, and employ collection agencies and legal counsel to pursue recovery of defaulted receivables. For our larger customers, detailed credit review procedures may be performed in advance of any sales being made. We sometimes require letters of credit, parental guarantees, prepayments or other forms of credit assurance from our larger customers to mitigate credit risk.

(f) Materials, Supplies, and Inventories—Our inventories as of December 31 consisted of:

(in millions)	2023		2022
Materials and supplies	$	186.6	$	150.6
Fossil fuel	74.5		62.7
Natural gas in storage	49.5		79.6
Total	$	310.6	$	292.9

Substantially all materials and supplies, fossil fuel, and natural gas in storage inventories are recorded using the weighted-average cost method of accounting.

(g) Regulatory Assets and Liabilities—The economic effects of regulation can result in regulated companies recording costs and revenues that are allowed in the ratemaking process in a period different from the period they would have been recognized by a nonregulated company. When this occurs, regulatory assets and regulatory liabilities are recorded on the balance sheet. Regulatory

2023 Form 10-K 62 Wisconsin Electric Power Company

assets represent deferred costs probable of recovery from customers that would have otherwise been charged to expense. Regulatory liabilities represent amounts that are expected to be refunded to customers in future rates or future costs already collected from customers in rates.

The recovery or refund of regulatory assets and liabilities is based on specific periods determined by our regulators or occurs over the normal operating period of the related assets and liabilities. If a previously recorded regulatory asset is no longer probable of recovery, the regulatory asset is reduced to the amount considered probable of recovery, and the reduction is charged to expense in the current period. See Note 7, Regulatory Assets and Liabilities, for more information.

(h) Property, Plant, and Equipment—We record property, plant, and equipment at cost. Cost includes material, labor, overhead, and both debt and equity components of AFUDC. Additions to and significant replacements of property are charged to property, plant, and equipment at cost; minor items are charged to other operation and maintenance expense. The cost of depreciable utility property less salvage value is charged to accumulated depreciation when property is retired.

We record straight-line depreciation expense over the estimated useful life of utility property using depreciation rates approved by the PSCW that include estimates for salvage value and removal costs. Annual utility composite depreciation rates were 3.03%, 3.06%, and 3.09% in 2023, 2022, and 2021, respectively.

We capitalize certain costs related to software developed or obtained for internal use and record these costs to amortization expense over the estimated useful life of the related software, which ranges from 3 to 15 years. If software is retired prior to being fully amortized, the difference is recorded as a loss on the income statement.

Third parties reimburse us for all or a portion of expenditures for certain capital projects. Such contributions in aid of construction costs are recorded as a reduction to property, plant, and equipment.

See Note 8, Property, Plant, and Equipment, for more information.

(i) Allowance for Funds Used During Construction—AFUDC is included in utility plant accounts and represents the cost of borrowed funds (AFUDC-Debt) used during plant construction, and a return on shareholders' capital (AFUDC-Equity) used for construction purposes. AFUDC-Debt is recorded as a reduction of interest expense, and AFUDC-Equity is recorded in other income, net.

Approximately 50% of our retail jurisdictional CWIP expenditures are subject to the AFUDC calculation. Our average AFUDC retail rates were 8.45%, 8.68%, and 8.68% for 2023, 2022, and 2021, respectively. Our average AFUDC wholesale rates were 6.70%, 5.35%, and 1.79% for 2023, 2022, and 2021, respectively.

We recorded the following AFUDC for the years ended December 31:

(in millions)	2023		2022		2021
AFUDC-Debt	$	13.0	$	6.9	$	2.9
AFUDC-Equity	41.0		18.8		7.9

(j) Asset Impairment—Intangible assets with indefinite lives are subject to an annual impairment test. Interim impairment tests are performed when impairment indicators are present. At December 31, 2023 and 2022, we had $12.1 million and $9.1 million, respectively, of indefinite-lived intangible assets consisting of spectrum frequencies purchased in 2022 and 2023. The spectrum frequencies enable us to transmit data and voice communications over a wavelength dedicated to us throughout our service territory. These indefinite-lived intangible assets are included in other long-term assets on our balance sheets. An impairment loss is recognized when the carrying amount of an asset is not recoverable and exceeds its fair value. An impairment loss is measured as the excess of the carrying amount of the intangible asset over its fair value. No impairment losses were recorded for our indefinite-lived intangible assets during the years ended December 31, 2023 and 2022.

We periodically assess the recoverability of certain long-lived assets when factors indicate the carrying value of such assets may be impaired or such assets are planned to be sold. Long-lived assets that would be subject to an impairment assessment generally include any assets within regulated operations that may not be fully recovered from our customers as a result of regulatory decisions that will be made in the future. An impairment loss is recognized when the carrying amount of an asset is not recoverable and exceeds its fair value. The carrying amount of an asset is not recoverable if it exceeds the sum of the undiscounted cash flows

2023 Form 10-K 63 Wisconsin Electric Power Company

expected to result from the use and eventual disposition of the asset. An impairment loss is measured as the excess of the carrying amount of the asset over its fair value.

We assess the likelihood of a disallowance of part of the cost of recently completed plant by considering factors such as applicable regulatory environment changes, our own recent rate orders, as well as recent rate orders of other regulated entities in similar jurisdictions. When it becomes probable that part of the cost of recently completed plant will be disallowed for rate-making purposes, we assess whether a reasonable estimate of the amount of the disallowance can be made. The estimated amount of the probable disallowance will then be deducted from the reported cost of the plant and recognized as an impairment loss.

When it becomes probable that a generating unit will be retired before the end of its useful life, we assess whether the generating unit meets the criteria for abandonment accounting. Generating units that are considered probable of abandonment are expected to cease operations in the near term, significantly before the end of their original estimated useful lives. If a generating unit meets the applicable criteria to be considered probable of abandonment, and the unit has been abandoned, we assess the likelihood of recovery of the remaining net book value of that generating unit at the end of each reporting period. If it becomes probable that regulators will disallow full recovery as well as a return on the remaining net book value of a generating unit that is either abandoned or probable of being abandoned, an impairment loss may be required. An impairment loss would be recorded if the remaining net book value of the generating unit is greater than the present value of the amount expected to be recovered from ratepayers, using an incremental borrowing rate. See Note 7, Regulatory Assets and Liabilities, and Note 8, Property, Plant, and Equipment, for more information.

(k) Asset Retirement Obligations—We recognize, at fair value, legal obligations associated with the retirement of long-lived assets that result from the acquisition, construction, development, and normal operation of the assets. An ARO liability is recorded, when incurred, for these obligations as long as the fair value can be reasonably estimated, even if the timing or method of settling the obligation is unknown. The associated retirement costs are capitalized as part of the related long-lived asset and are depreciated over the useful life of the asset. The ARO liabilities are accreted each period using the credit-adjusted risk-free interest rates associated with the expected settlement dates of the AROs. These rates are determined when the obligations are incurred. Subsequent changes resulting from revisions to the timing or the amount of the original estimate of undiscounted cash flows are recognized as an increase or a decrease to the carrying amount of the liability and the associated capitalized retirement costs. We recognize regulatory assets or liabilities for the timing differences between when we recover an ARO in rates and when we recognize the associated retirement costs. See Note 10, Asset Retirement Obligations, for more information.

(l) Stock-Based Compensation—Our employees participate in the WEC Energy Group stock-based compensation plans. In accordance with the Omnibus Stock Incentive Plan, WEC Energy Group provides long-term incentives through its equity interests to its non-employee directors, officers, and other key employees. The plan provides for the granting of stock options, restricted stock, performance shares, and other stock-based awards. Awards may be paid in WEC Energy Group common stock, cash, or a combination thereof. In addition to those shares of WEC Energy Group common stock that were subject to awards outstanding as of May 6, 2021, when the plan was last approved by shareholders, 9.0 million shares of WEC Energy Group common stock were reserved for issuance under the plan.

Stock-based compensation expense is allocated to us based on the outstanding awards held by our employees and our allocation of labor costs. Awards classified as equity awards are measured based on their grant-date fair value. Awards classified as liability awards are recorded at fair value each reporting period. We account for forfeitures as they occur, rather than estimating potential future forfeitures and recording them over the vesting period.

Stock Options

Our employees are granted WEC Energy Group non-qualified stock options that generally vest on a cliff-basis after three years. The exercise price of a stock option under the plan cannot be less than 100% of the fair market value of WEC Energy Group common stock on the grant date. Historically, all stock options have been granted with an exercise price equal to the fair market value of WEC Energy Group common stock on the date of the grant. Options vest immediately upon retirement, death, or disability; however, they may not be exercised within six months of the grant date except in connection with certain termination of employment events following a change in control. Options expire no later than 10 years from the date of grant.

2023 Form 10-K 64 Wisconsin Electric Power Company

WEC Energy Group stock options are classified as equity awards. The fair value of each stock option was calculated using a binomial option-pricing model. The following table shows the estimated weighted-average fair value per stock option granted to our employees along with the weighted-average assumptions used in the valuation models:

	2023			2022			2021
Stock options granted	30,495			51,511			60,108
Estimated weighted-average fair value per stock option	$	19.58		$	14.71		$	13.20
Assumptions used to value the options:
Risk-free interest rate	3.8% – 4.8%			0.2% – 1.6%			0.1% – 0.9%
Dividend yield	3.2		%	3.2		%	2.9		%
Expected volatility	22.0		%	21.0		%	21.0		%
Expected life (years)	8.3			8.7			8.7

The risk-free interest rate was based on the United States Treasury interest rate with a term consistent with the expected life of the stock options. The dividend yield was based on WEC Energy Group's dividend rate at the time of the grant and historical stock prices. Expected volatility and expected life assumptions were based on WEC Energy Group's historical experience.

Restricted Shares

WEC Energy Group restricted shares granted to our employees have a vesting period of three years with one-third of the award vesting on each anniversary of the grant date. The restricted shares are classified as equity awards.

Performance Units

Officers and other key employees are granted performance units under the WEC Energy Group Performance Unit Plan. All grants of performance units are settled in cash and are accounted for as liability awards accordingly. Performance units accrue forfeitable dividend equivalents in the form of additional performance units. The fair value of the performance units reflects our estimate of the final expected value of the awards, which is based on WEC Energy Group's stock price and performance achievement under the terms of the award. Stock-based compensation costs are generally recorded over the performance period, which is three years.

The ultimate number of units that will be awarded is dependent on WEC Energy Group's total shareholder return (stock price appreciation plus dividends) as compared to the total shareholder return of a peer group of companies over three years, as well as other performance metrics, as may be determined by the Compensation Committee. Under the terms of awards granted prior to 2023, participants may earn between 0% and 175% of the performance unit award based on WEC Energy Group's total shareholder return. Pursuant to the plan terms governing these awards, these percentages can be adjusted upwards or downwards by up to 10% based on WEC Energy Group's performance against additional performance measures, if any, adopted by the Compensation Committee.

The WEC Energy Group Performance Unit Plan was amended and restated, effective January 1, 2023. In accordance with the amended plan, the Compensation Committee selected multiple performance measures that will be weighted to determine the ultimate payout for the awards granted in 2023 and 2024. The ultimate number of units awarded will be based on WEC Energy Group's total shareholder return compared to the total shareholder return of a peer group of companies over three years (55%), and WEC Energy Group's performance against the weighted average authorized ROE of all of its utility subsidiaries (45%). In addition, the Compensation Committee selected the level of WEC Energy Group's stock price to earnings ratio compared to its peer companies as a performance measure that can increase the payout by up to 25%. In no event can the performance unit payout be greater than 200% of the target award.

See Note 11, Common Equity, for more information on WEC Energy Group's stock-based compensation plans.

(m) Leases—We recognize a right of use asset and lease liability for operating and finance leases with a term of greater than one year. As a policy election, we account for each lease component separately from the nonlease components of a contract.

We are currently party to several easement agreements that allow us access to land we do not own for the purpose of constructing and maintaining certain electric power and natural gas equipment. The majority of payments we make related to easements relate

2023 Form 10-K 65 Wisconsin Electric Power Company

to our renewable generating facilities. We have not classified our easements as leases because we view the entire parcel of land specified in our easement agreements to be the identified asset, not just that portion of the parcel that contains our easement. As such, we have concluded that we do not control the use of an identified asset related to our easement agreements, nor do we obtain substantially all of the economic benefits associated with these shared-use assets.

See Note 15, Leases, for more information.

(n) Income Taxes—We follow the liability method in accounting for income taxes. Accounting guidance for income taxes requires the recording of deferred assets and liabilities to recognize the expected future tax consequences of events that have been reflected in our financial statements or tax returns and the adjustment of deferred tax balances to reflect tax rate changes. We are required to assess the likelihood that our deferred tax assets would expire before being realized. If we conclude that certain deferred tax assets are likely to expire before being realized, a valuation allowance would be established against those assets. GAAP requires that, if we conclude in a future period that it is more likely than not that some or all of the deferred tax assets would be realized before expiration, we reverse the related valuation allowance in that period. Any change to the allowance, as a result of a change in judgment about the realization of deferred tax assets, is reported in income tax expense.

ITCs associated with regulated operations are deferred and amortized over the life of the assets. PTCs are recognized in the period in which such credits are generated. The amount of the credit is based upon power production from our qualifying generation facilities. We are included in WEC Energy Group's consolidated federal and state income tax returns. In accordance with our tax allocation agreement with WEC Energy Group, we are allocated income tax payments and refunds based upon the benefit for loss method, where attributes are realized when WEC Energy Group is able to realize them.

We recognize interest and penalties accrued related to unrecognized tax benefits in income tax expense in our income statements.

The IRA contains a tax credit transferability provision that allows us to sell PTCs produced after December 31, 2022, to third parties. In September 2023, under this transferability provision, WEC Energy Group entered into an agreement to sell substantially all of our 2023 PTCs to a third party. We elect to account for tax credits transferred under the scope of ASC 740. We include the discount from the sale of tax credits as a component of income tax expense. We will also include any expected proceeds from the sale of tax credits in the evaluation of the realizability of deferred tax assets related to PTCs. The sale of tax credits is presented in the operating activities section of the statements of cash flows consistent with the presentation of cash taxes paid.

In April 2023, the IRS issued Revenue Procedure 2023-15, which provides a safe harbor method of accounting that taxpayers may use to determine whether expenses to repair, maintain, replace, or improve natural gas transmission and distribution property must be capitalized for tax purposes. We are currently evaluating the impact this guidance may have on our financial statements and related disclosures.

See Note 16, Income Taxes, for more information.

(o) Fair Value Measurements—Fair value is the price that would be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants at the measurement date (exit price).

Fair value accounting rules provide a fair value hierarchy that prioritizes the inputs used to measure fair value. The hierarchy gives the highest priority to unadjusted quoted prices in active markets for identical assets or liabilities (Level 1 measurement) and the lowest priority to unobservable inputs (Level 3 measurement). The three levels of the fair value hierarchy are defined as follows:

Level 1 – Quoted prices are available in active markets for identical assets or liabilities as of the reporting date. Active markets are those in which transactions for the asset or liability occur in sufficient frequency and volume to provide pricing information on an ongoing basis.

Level 2 – Pricing inputs are observable, either directly or indirectly, but are not quoted prices included within Level 1. Level 2 includes those financial instruments that are valued using external inputs within models or other valuation methods.

Level 3 – Pricing inputs include significant inputs that are generally less observable from objective sources. These inputs may be used with internally developed methods that result in management's best estimate of fair value. Level 3 instruments include those that may be more structured or otherwise tailored to customers' needs.

2023 Form 10-K 66 Wisconsin Electric Power Company

Assets and liabilities are classified in their entirety based on the lowest level of input that is significant to the fair value measurement. We use a mid-market pricing convention (the mid-point price between bid and ask prices) as a practical measure for valuing certain derivative assets and liabilities. We primarily use a market approach for recurring fair value measurements and attempt to use valuation techniques that maximize the use of observable inputs and minimize the use of unobservable inputs.

When possible, we base the valuations of our derivative assets and liabilities on quoted prices for identical assets and liabilities in active markets. These valuations are classified in Level 1. The valuations of certain contracts not classified as Level 1 may be based on quoted market prices received from counterparties and/or observable inputs for similar instruments. Transactions valued using these inputs are classified in Level 2. Certain derivatives, such as FTRs, are categorized in Level 3 due to the significance of unobservable or internally-developed inputs. Our FTRs are valued using MISO auction prices.

See Note 17, Fair Value Measurements, for more information.

(p) Derivative Instruments—We use derivatives as part of our risk management program to manage the risks associated with the price volatility of purchased power, generation, and natural gas costs for the benefit of our customers. Our approach is non-speculative and designed to mitigate risk. Our regulated hedging programs are approved by the PSCW.

We record derivative instruments on our balance sheets as assets or liabilities measured at fair value, unless they qualify for the normal purchases and sales exception, and are so designated. We continually assess our contracts designated as normal and will discontinue the treatment of these contracts as normal if the required criteria are no longer met. Changes in the derivative's fair value are recognized currently in earnings unless specific hedge accounting criteria are met or we receive regulatory treatment for the derivative. For most energy related physical and financial contracts in our regulated operations that qualify as derivatives, the PSCW allows the effects of fair value accounting to be offset to regulatory assets and liabilities.

We classify derivative assets and liabilities as current or long-term on our balance sheets based on the maturities of the underlying contracts. Cash flows from derivative activities are presented in the same category as the item being hedged within operating activities on our statements of cash flows.

Derivative accounting rules provide the option to present certain asset and liability derivative positions net on the balance sheets and to net the related cash collateral against these net derivative positions. We elected not to net these items. On our balance sheets, cash collateral provided to others is reflected in other current assets. See Note 18, Derivative Instruments, for more information.

(q) Guarantees—We follow the guidance of the Guarantees Topic of the FASB ASC, which requires, under certain circumstances, that the guarantor recognize a liability for the fair value of the obligation undertaken in issuing the guarantee at its inception. As of December 31, 2023, we had $26.0 million of standby letters of credit issued by financial institutions for the benefit of third parties that have extended credit to us, which automatically renew each year unless proper termination notice is given. These amounts are not reflected on our balance sheets.

(r) Employee Benefits—The costs of pension and OPEB plans are expensed over the periods during which employees render service. These costs are distributed among WEC Energy Group's subsidiaries based on current employment status and actuarial calculations, as applicable. Our regulators allow recovery in rates for our net periodic benefit cost calculated under GAAP. See Note 19, Employee Benefits, for more information.

(s) Customer Deposits and Credit Balances—When utility customers apply for new service, they may be required to provide a deposit for the service. Customer deposits are recorded within other current liabilities on our balance sheets.

Utility customers can elect to be on a budget plan. Under this type of plan, a monthly installment amount is calculated based on estimated annual usage. During the year, the monthly installment amount is reviewed by comparing it to actual usage. If necessary, an adjustment is made to the monthly amount. Annually, the budget plan is reconciled to actual annual usage. Payments in excess of actual customer usage are recorded within other current liabilities on our balance sheets.

(t) Environmental Remediation Costs—We are subject to federal and state environmental laws and regulations that in the future may require us to pay for environmental remediation at sites where we have been, or may be, identified as a potentially responsible party. Loss contingencies may exist for the remediation of hazardous substances at various potential sites, including CCR

2023 Form 10-K 67 Wisconsin Electric Power Company

landfills and manufactured gas plant sites. See Note 10, Asset Retirement Obligations, for more information regarding CCR landfills and Note 22, Commitments and Contingencies, for more information regarding manufactured gas plant sites.

We record environmental remediation liabilities when site assessments indicate remediation is probable, and we can reasonably estimate the loss or a range of losses. The estimate includes both our share of the liability and any additional amounts that will not be paid by other potentially responsible parties or the government. When possible, we estimate costs using site-specific information but also consider historical experience for costs incurred at similar sites. Remediation efforts for a particular site generally extend over a period of several years. During this period, the laws governing the remediation process may change, as well as site conditions, potentially affecting the cost of remediation.

We have received approval to defer certain environmental remediation costs, as well as estimated future costs, through a regulatory asset. The recovery of deferred costs is subject to the PSCW's approval.

We review our estimated costs of remediation annually for our manufactured gas plant sites and CCR landfills. We adjust the liabilities and related regulatory assets, as appropriate, to reflect the new cost estimates. Any material changes in cost estimates are adjusted throughout the year.

(u) Customer Concentrations of Credit Risk—The geographic concentration of our customers did not contribute significantly to our overall exposure to credit risk. We periodically review customers' credit ratings, financial statements, and historical payment performance and require them to provide collateral or other security as needed. Our credit risk exposure is mitigated by our recovery mechanism for uncollectible expense discussed in Note 1(d), Operating Revenues. As a result, we did not have any significant concentrations of credit risk at December 31, 2023. In addition, there were no customers that accounted for more than 10% of our revenues for the year ended December 31, 2023.

NOTE 2—ACQUISITIONS

In accordance with Topic 805: Clarifying the Definition of a Business (ASU 2017-01), transactions are evaluated and are accounted for as acquisitions of assets or businesses, and transaction costs are capitalized in asset acquisitions. It was determined that all of the below acquisitions met the criteria of asset acquisitions.

Acquisitions of Electric Generation Facilities in Wisconsin

In June 2023, we completed the acquisition of 100 MWs of West Riverside's nameplate capacity, in the first of two potential option exercises. West Riverside is a commercially operational dual fueled combined cycle generation facility in Beloit, Wisconsin. Our investment was $95.3 million. In addition, WPS filed a request with the PSCW in September 2023 to exercise a second option to acquire an additional 100 MWs of West Riverside's nameplate capacity. As it did with the first option, in October 2023, WPS filed for approval to assign its ownership interest pursuant to this second option to us. If these approvals are obtained, our incremental share of this investment is expected to be approximately $100 million, with the transaction expected to close in 2024.

In January 2023, we, along with WPS, completed the acquisition of Whitewater, a commercially operational 236.5 MW dual fueled (natural gas and low sulfur fuel oil) combined cycle electrical generation facility in Whitewater, Wisconsin. Our share of the cost of this facility was $38.0 million for 50% of the capacity.

NOTE 3—DISPOSITION

Sale of Real Estate

In June 2023, we sold approximately 192 acres of real estate at our former Pleasant Prairie power plant site that was no longer being utilized in our operations, for $23.0 million, which is net of closing costs. As a result of the sale, a pre-tax gain in the amount of $22.2 million was recorded within other operation and maintenance expense on our income statement. The book value of the real estate included in the sale was not material and, therefore, was not presented as held for sale.

2023 Form 10-K 68 Wisconsin Electric Power Company

NOTE 4—RELATED PARTIES

We routinely enter into transactions with related parties, including WEC Energy Group, its other subsidiaries, ATC, and other affiliated entities.

We provide and receive services, property, and other items of value to and from our parent, WEC Energy Group, and other subsidiaries of WEC Energy Group pursuant to an AIA that became effective in 2017. The AIA was approved by the appropriate regulators, including the PSCW. In accordance with the AIA, WBS provides several categories of services to us (including financial, human resource, and administrative services). As required by FERC regulations for centralized service companies, WBS renders services at cost. Services provided by any regulated subsidiary of WEC Energy Group to another regulated subsidiary or WBS are provided at cost, and any services provided by a regulated subsidiary to a nonregulated subsidiary of WEC Energy Group are provided at the greater of cost or fair market value.

We pay ATC for transmission and other related services it provides. In addition, we provide a variety of operational, maintenance, and project management work for ATC, which is reimbursed by ATC. Services are billed to and from ATC under agreements approved by the PSCW, at each of our fully allocated costs. We are also required to initially fund the construction of transmission infrastructure upgrades needed for new generation projects. ATC owns these transmission assets and reimburses us for these costs when the new generation is placed in service.

Our balance sheets included the following receivables and payables for services provided to or received from ATC:

(in millions)	December 31, 2023		December 31, 2022
Accounts receivable
Services provided to ATC	$	0.9	$	0.7
Amounts due from ATC for transmission infrastructure upgrades (1)	39.5		23.3
Accounts payable
Services received from ATC	36.7		20.0

(1)     The transmission infrastructure upgrades were primarily related to the construction of our renewable energy projects.

2023 Form 10-K 69 Wisconsin Electric Power Company

The following table shows activity associated with our related party transactions for the years ended December 31:

(in millions)	2023		2022		2021
Transactions with WPS
Natural gas related purchases from WPS (1)	$	1.3	$	3.3	$	2.9
Charges to WPS for services and other items (2)	16.2		13.3		11.8
Charges from WPS for services and other items (2)	11.3		10.7		9.4
Transactions with WG
Natural gas related purchases from WG (1)	19.7		6.2		5.9
Natural gas related sales to WG (1)	0.3		1.3		0.3
Charges to WG for services and other items (2)	38.3		39.5		40.4
Charges from WG for services and other items (2)	27.9		29.8		29.7
Transactions with UMERC
Charges to UMERC for services and other items (2)	11.8		13.7		10.5
Charges from UMERC for services and other items (2)	2.0		1.2		1.2
Transactions with Bluewater
Charges from Bluewater for storage service fees (3)	17.2		14.8		13.6
Charges from Bluewater for other operating fees (3)	4.1		3.3		1.4
Natural gas related sales to Bluewater (1)	2.8		2.7		2.6
Charges to Bluewater for services and other items (2)	2.7		2.7		3.0
Transactions with We Power
Lease payments and other lease-related charges from We Power (4)	422.0		412.6		406.0
Charges to We Power for services and other items (2)	7.8		4.2		6.7
Transactions with WBS
Charges to WBS for services and other items (2)	41.1		49.5		67.8		(5)
Charges from WBS for services and other items (2)	113.3		123.1		123.8
Transactions with ATC
Charges to ATC for services and construction	8.1		9.3		14.9
Charges from ATC for network transmission services	248.8		239.3		240.4
Net refund (payment) from (to) ATC related to FERC ROE orders	—		(0.1)		5.1

(1)    Includes amounts related to the purchase or sale of natural gas and/or pipeline capacity.

(2)    Includes amounts charged for services, pass through costs, asset and liability transfers, and other items in accordance with the approved AIA.

(3)    We have a long-term service agreement with a wholly owned subsidiary of Bluewater that was previously approved by the PSCW. Bluewater owns natural gas storage facilities in Michigan and provides a portion of our current storage needs.

(4)    We make lease payments to We Power for PWGS Units 1 and 2 and ERGS Units 1 and 2. See Note 15, Leases, for more information.

(5)     Includes $11.3 million for the transfer of certain software assets to WBS.

2023 Form 10-K 70 Wisconsin Electric Power Company

NOTE 5—OPERATING REVENUES

For more information about our significant accounting policies related to operating revenues, see Note 1(d), Operating Revenues.

Disaggregation of Operating Revenues

The following tables present our operating revenues disaggregated by revenue source for our utility segment. We do not have any revenues associated with our other segment. We disaggregate revenues into categories that depict how the nature, amount, timing, and uncertainty of revenues and cash flows are affected by economic factors. Revenues are further disaggregated by electric and natural gas operations and then by customer class. Each customer class within our electric and natural gas operations has different expectations of service, energy and demand requirements, and can be impacted differently by regulatory activities within their jurisdictions.

	Year Ended December 31
(in millions)	2023		2022		2021
Wisconsin Electric Power Company
Electric utility	$	3,540.2	$	3,448.7	$	3,171.6
Natural gas utility	489.8		606.8		474.2
Total revenues from contracts with customers	4,030.0		4,055.5		3,645.8
Other operating revenues	15.0		14.8		18.7
Total operating revenues	$	4,045.0	$	4,070.3	$	3,664.5

Revenues from Contracts with Customers

Electric Utility Operating Revenues

The following table disaggregates electric utility operating revenues into customer class:

	Year Ended December 31
(in millions)	2023		2022		2021
Residential	$	1,480.6	$	1,376.3	$	1,306.2
Small commercial and industrial	1,177.2		1,095.0		1,019.7
Large commercial and industrial	616.0		629.1		568.6
Other	21.1		20.4		20.2
Total retail revenues	3,294.9		3,120.8		2,914.7
Wholesale	40.9		58.4		71.0
Resale	173.7		224.3		148.2
Steam	25.2		28.4		28.7
Other utility revenues	5.5		16.8		9.0
Total electric utility operating revenues	$	3,540.2	$	3,448.7	$	3,171.6

Natural Gas Utility Operating Revenues

The following table disaggregates natural gas utility operating revenues into customer class:

	Year Ended December 31
(in millions)	2023		2022		2021
Residential	$	323.3	$	397.8	$	309.1
Commercial and industrial	148.2		193.7		141.9
Total retail revenues	471.5		591.5		451.0
Transportation	21.6		17.8		17.3
Other utility revenues (1)	(3.3)		(2.5)		5.9
Total natural gas utility operating revenues	$	489.8	$	606.8	$	474.2

(1)    Includes the revenues subject to our purchased gas recovery mechanism, which fluctuate based on actual natural gas costs incurred, compared with the recovery of natural gas costs that were anticipated in rates.

2023 Form 10-K 71 Wisconsin Electric Power Company

Other Operating Revenues

Other operating revenues consist of the following:

	Year Ended December 31
(in millions)	2023		2022		2021
Late payment charges	$	12.2	$	12.1	$	13.3
Rental revenues	2.5		2.5		3.0
Alternative revenues	0.3		0.2		2.4
Total other operating revenues	$	15.0	$	14.8	$	18.7

NOTE 6—CREDIT LOSSES

The table below shows our gross third-party receivable balances and related allowance for credit losses.

(in millions)	December 31, 2023			December 31, 2022
Accounts receivable and unbilled revenues	$	617.5		$	632.3
Allowance for credit losses	44.5			49.7
Accounts receivable and unbilled revenues, net (1)	$	573.0		$	582.6
Total accounts receivable, net – past due greater than 90 days (1)	$	37.2		$	35.8
Past due greater than 90 days – collection risk mitigated by regulatory mechanisms (1)	94.1		%	97.5		%

(1)    Our exposure to credit losses for certain regulated utility customers is mitigated by a regulatory mechanism we have in place. Specifically, our residential tariffs include a mechanism for cost recovery or refund of uncollectible expense based on the difference between actual uncollectible write-offs and the amounts recovered in rates. As a result, at December 31, 2023, $342.5 million, or 59.8%, of our net accounts receivable and unbilled revenues balance had regulatory protections in place to mitigate the exposure to credit losses.

A rollforward of the allowance for credit losses is included below:

	Year Ended December 31
(in millions)	2023		2022		2021
Balance at January 1	$	49.7	$	51.4	$	59.3
Provision for credit losses	23.8		27.3		24.8
Provision for credit losses deferred for future recovery or refund	45.7		34.0		(0.3)
Write-offs charged against the allowance	(94.1)		(83.4)		(47.6)
Recoveries of amounts previously written off	19.4		20.4		15.2
Balance at December 31	$	44.5	$	49.7	$	51.4

The allowance for credit losses decreased during the year ended December 31, 2023, primarily related to lower customer energy costs (driven by the warmer weather during the fourth quarter of 2023 when compared to the same quarter in 2022 and lower natural gas prices), which contributed to a reduction in past due accounts receivable balances and a related decrease in the allowance for credit losses. Customer write-offs also contributed to the decrease in the allowance for credit losses. After a customer is disconnected for a period of time without payment on their account, we will write off that customer balance.

The allowance for credit losses decreased during the year ended December 31, 2022, driven by customer write-offs related to collection practices returning to pre-pandemic levels in 2021, including the restoration of our ability to disconnect customers. Partially offsetting the decrease in the allowance for credit losses, we believe that the high energy costs that customers were seeing, which were driven by high natural gas prices, contributed to higher past due accounts receivable balances and a related increase in the allowance of credit losses.

The allowance for credit losses decreased during the year ended December 31, 2021, primarily related to normal collection practices resuming in April 2021. Higher year-over-year natural gas prices drove an increase in gross accounts receivable balances, partially offsetting the decrease in the allowance for credit losses attributed to collection efforts.

2023 Form 10-K 72 Wisconsin Electric Power Company

NOTE 7—REGULATORY ASSETS AND LIABILITIES

The following regulatory assets were reflected on our balance sheets as of December 31:

(in millions)	2023		2022		See Note
Regulatory assets (1) (2)
Finance leases	$	1,109.7	$	1,072.0	15
Plant retirement related items	595.5		632.7
Income tax related items	373.1		382.1		16
Pension and OPEB costs (3)	348.9		337.2		19, 24
SSR (4)	113.2		123.5
Securitization	85.9		92.4		21
Uncollectible expense	62.1		16.4		6
Derivatives	45.2		40.3		1(p)
AROs	41.2		41.1		1(k), 10
Energy efficiency programs (5)	23.3		17.7
We Power generation (6)	4.7		21.6
Other, net	57.9		40.5
Total regulatory assets	$	2,860.7	$	2,817.5

(1)    Based on prior and current rate treatment, we believe it is probable that we will continue to recover from customers the regulatory assets in this table. In accordance with GAAP, our regulatory assets do not include the allowance for ROE that is capitalized for regulatory purposes. This allowance was $16.5 million and $14.7 million at December 31, 2023 and 2022, respectively.

(2)    As of December 31, 2023, we had $1.9 million of regulatory assets not earning a return, $4.7 million of regulatory assets earning a return based on short-term interest rates, and $129.7 million of regulatory assets earning a return based on long-term interest rates. The regulatory assets not earning a return relate to certain environmental remediation costs. The other regulatory assets in the table either earn a return at our weighted average cost of capital or the cash has not yet been expended, in which case the regulatory assets are offset by liabilities.

(3)    Primarily represents the unrecognized future pension and OPEB costs related to our defined benefit pension and OPEB plans. We are authorized recovery of these regulatory assets over the average remaining service life of each plan.

(4)    This regulatory asset relates to our 2014 announcement to retire the PIPP. Despite our intent to retire the PIPP, MISO designated the PIPP as an SSR, which meant the PIPP's operation was necessary for reliability, and the plant could not be shut down until new generation or transmission facilities were built. In December 2014, the PSCW authorized escrow accounting for our SSR revenues because of the fluctuations in the actual revenues we received under the PIPP SSR agreements. The rate order we received from the PSCW in December 2019 authorized recovery of this SSR regulatory asset over a 15-year period that began on January 1, 2020.

(5)    Represents amounts recoverable from customers related to programs designed to meet energy efficiency standards.

(6)    Represents amounts recoverable from customers related to our costs of the generating units leased from We Power, including subsequent capital additions.

2023 Form 10-K 73 Wisconsin Electric Power Company

The following regulatory liabilities were reflected on our balance sheets as of December 31:

(in millions)	2023		2022		See Note
Regulatory liabilities
Removal costs (1)	$	758.9	$	718.1
Income tax related items	683.5		716.1		16
Pension and OPEB benefits (2)	124.0		144.4		19, 24
Electric transmission costs (3)	23.9		0.2
Energy efficiency programs (4)	10.6		1.0
Derivatives	4.5		39.1		1(p)
Other, net	31.3		19.9
Total regulatory liabilities	$	1,636.7	$	1,638.8
Balance sheet presentation
Other current liabilities	$	5.3	$	1.4
Regulatory liabilities	1,631.4		1,637.4
Total regulatory liabilities	$	1,636.7	$	1,638.8

(1)    Represents amounts collected from customers to cover the future cost of property, plant, and equipment removals that are not legally required. Legal obligations related to the removal of property, plant, and equipment are recorded as AROs. See Note 10, Asset Retirement Obligations, for more information on our legal obligations.

(2)    Primarily represents the unrecognized future pension and OPEB benefits related to our defined benefit pension and OPEB plans. We will amortize these regulatory liabilities into net periodic benefit cost over the average remaining service life of each plan.

(3)    In accordance with the PSCW's approval of escrow accounting for our ATC and MISO network transmission expenses, we defer as a regulatory asset or liability the difference between actual transmission costs and those included in rates until recovery or refund is authorized in a future rate proceeding.

(4)    Represents amounts refundable to customers related to programs designed to meet energy efficiency standards.

Pleasant Prairie Power Plant

The Pleasant Prairie power plant was retired on April 10, 2018. The net book value of this plant was $542.4 million at December 31, 2023, representing book value less cost of removal and accumulated depreciation. In addition, previously deferred unprotected tax benefits from the Tax Legislation related to the unrecovered balance of this plant were $16.4 million as of December 31, 2023. The net amount of $526.0 million was classified as a regulatory asset on our balance sheet at December 31, 2023 due to the retirement of the plant. This regulatory asset does not include certain other previously recorded deferred tax liabilities of $147.8 million related to the retired Pleasant Prairie power plant. Pursuant to our rate order issued by the PSCW in December 2019, we will continue to amortize this regulatory asset on a straight-line basis through 2039, using the composite depreciation rates approved by the PSCW before this plant was retired. The amortization is included in depreciation and amortization in the income statement. We also have FERC approval to continue to collect the net book value of the Pleasant Prairie power plant using the approved composite depreciation rates, in addition to a return on the remaining net book value.

We received approval from the PSCW in December 2019 to collect a full return of the net book value of the Pleasant Prairie power plant and a return on all but $100 million of the net book value. During May 2021, we securitized the remaining $100 million of the Pleasant Prairie power plant's book value, the carrying costs accrued on the $100 million during the securitization process, and the related financing fees, in accordance with a written order issued by the PSCW in November 2020. See Note 21, Variable Interest Entities, for more information on this securitization.

Presque Isle Power Plant

Pursuant to MISO's April 2018 approval of the retirement of the PIPP, these units were retired on March 31, 2019, and the plant was reclassified to a regulatory asset on our balance sheets. After the retirement of the PIPP, a portion of the regulatory asset and related cost of removal reserve was transferred to UMERC for recovery from its retail customers. On our balance sheet, the net book value of the PIPP was $141.2 million at December 31, 2023, representing book value less cost of removal and accumulated depreciation. In addition, previously deferred unprotected tax benefits from the Tax Legislation related to our unrecovered balance of these units were $4.8 million, resulting in a net amount of $136.4 million at December 31, 2023. This regulatory asset does not

2023 Form 10-K 74 Wisconsin Electric Power Company

include certain other previously recorded deferred tax liabilities of $38.5 million related to the retired PIPP. Effective with our rate order issued by the PSCW in December 2019, we received approval to collect a return of and on our share of the net book value of the PIPP, and as a result, will continue to amortize the regulatory assets on a straight-line basis through 2037, using the composite depreciation rates approved by the PSCW before the units were retired. The amortization is included in depreciation and amortization in the income statement. We also have FERC approval to continue to collect the net book value of the PIPP using the approved composite depreciation rates, in addition to a return on the net book value.

NOTE 8—PROPERTY, PLANT, AND EQUIPMENT

Property, plant, and equipment consisted of the following at December 31:

(in millions)	2023		2022
Electric – generation	$	2,721.3	$	2,200.0
Electric – distribution	6,116.7		5,822.4
Natural gas – distribution, storage, and transmission	2,059.4		1,757.0
Property, plant, and equipment to be retired	783.7		812.5
Other	1,087.0		1,044.9
Less: Accumulated depreciation	3,530.3		3,213.4
Net	9,237.8		8,423.4
CWIP	624.7		556.1
Net utility and non-utility property, plant, and equipment	9,862.5		8,979.5
Property under finance leases	3,206.8		3,248.8
Less: Accumulated amortization	1,483.8		1,509.7
Net leased facilities	1,723.0		1,739.1
Total property, plant, and equipment	$	11,585.5	$	10,718.6

Severance Liability for Plant Retirements

We have severance liabilities related to past and future plant retirements recorded in other current and other long-term liabilities on our balance sheets. Activity related to these severance liabilities for the years ended December 31 was as follows:

(in millions)	2023		2022		2021
Severance liability at January 1	$	13.5	$	3.3	$	0.7
Severance expense	1.6		10.2		3.0
Severance payments	—		—		(0.4)
Total severance liability at December 31	$	15.1	$	13.5	$	3.3

Plant to be Retired

Oak Creek Power Plant Units 5-8

As a result of a PSCW approval in December 2022 for the acquisition and construction of Darien, the retirement of OCPP Units 5-8 became probable. In early 2023, we received additional approvals for electric generation facilities, including Koshkonong and 100 MWs of West Riverside. See Note 2, Acquisitions, for more information on the West Riverside acquisition, which was completed in June 2023. OCPP Units 5 and 6 are expected to be retired by May 2024, while OCPP Units 7 and 8 are expected to be retired by late 2025. The total net book value of our ownership share of OCPP Units 5-8 was $783.7 million at December 31, 2023, which does not include deferred taxes. This amount was classified as plant to be retired within property, plant, and equipment on our balance sheet. These units are included in rate base, and we continue to depreciate them on a straight-line basis using the composite depreciation rates approved by the PSCW.

Public Service Building and Steam Tunnel Assets

During a significant rain event in May 2020, an underground steam tunnel in downtown Milwaukee flooded and steam vented into our PSB. The damage to the building and adjacent steam tunnel assets from the flooding and steam was extensive and required

2023 Form 10-K 75 Wisconsin Electric Power Company

significant repairs and restorations. As of December 31, 2023, we had incurred $95.3 million of costs related to these repairs and restorations. In June 2021, we received approval from the PSCW to restore the PSB and adjacent steam tunnel assets and to defer the project costs, net of insurance proceeds, as a component of rate base. As a result, we do not currently expect a significant impact to our future results of operations.

NOTE 9—JOINTLY OWNED UTILITY FACILITIES

We hold joint ownership interests in certain electric generating facilities. We are entitled to our share of generating capability and output of each facility equal to our respective ownership interest. We have supplied our own financing for all jointly owned projects. We pay our ownership share of additional construction costs, fuel inventory purchases, and operating expenses, unless specific agreements have been executed to limit our maximum exposure to additional costs. We record our proportionate share of significant jointly owned electric generating facilities as property, plant, and equipment on the balance sheets. In addition, our proportionate share of direct expenses for the joint operation of these plants is recorded within operating expenses in the income statements.

Information related to jointly owned utility facilities at December 31, 2023 was as follows:

Jointly-Owned Utility Facilities	Ownership		Share of Capacity (MW)	In-Service /Acquisition Date	Operating Owner	Property, Plant, and Equipment		Accumulated Depreciation		CWIP
(in millions, except for percentages and MW)
West Riverside (1) (3)	13.8	%	84.9	2023	WE	$	108.7	$	(11.3)	$	0.9
Badger Hollow II (2)	66.7	%	100.0	2023	WE	170.1		(0.3)		0.1
Weston RICE units (1)	50.0	%	65.0	2023	WPS	92.4		(1.3)		—
Whitewater (1) (4)	50.0	%	121.4	2023	WE	125.7		(93.6)		0.3

(1)    Capacity is based on rated capacity, which is the net power output under average operating conditions with equipment in an average state of repair as of a given month in a given year. Values are primarily based on the net dependable expected capacity ratings for summer 2024 established by tests and may change slightly from year to year. The summer period is the most relevant for capacity planning purposes. This is a result of continually reaching demand peaks in the summer months, primarily due to air conditioning demand.

(2)     Capacity for solar generating facilities is based on nameplate capacity, which is the maximum output that a generator should produce at continuous full power.

(3)    We acquired our ownership interest in June 2023. In September 2023, WPS filed a request with the PSCW to exercise a second option to acquire an additional 100 MWs of West Riverside's nameplate capacity. WPS subsequently filed for approval to assign its ownership interest pursuant to this second option to us. See Note 2, Acquisitions, for more information.

(4)    Effective January 1, 2023, we, along with WPS, completed the acquisition of Whitewater. See Note 2, Acquisitions, for more information.

We, along with WPS and an unaffiliated utility, received PSCW approval to construct Koshkonong, a utility-scale solar-powered electric generating facility. The project will be located in Dane County, Wisconsin and once fully constructed, we will own 75%, or 225 MWs of solar generation of this project. Commercial operation of the solar facility is targeted for 2026. Our CWIP balance for Koshkonong was not significant as of December 31, 2023.

We, along with WPS and an unaffiliated utility, received PSCW approval to construct Paris, a utility-scale solar-powered electric generating facility with a battery energy storage system. The project will be located in Kenosha County, Wisconsin and once fully constructed, we will own 75%, or 150 MWs of solar generation and 82 MWs of battery storage of this project. Commercial operation of the solar facility is targeted for 2024 and construction of the battery storage is expected to be completed in 2025. Our CWIP balance for Paris was $279.1 million as of December 31, 2023.

We, along with WPS and an unaffiliated utility, received PSCW approval to construct Darien, a utility-scale solar-powered electric generating facility. The project will be located in Rock and Walworth counties, Wisconsin and once fully constructed, we will own 75%, or 188 MWs of solar generation of this project. Commercial operation of the solar facility is targeted for 2024. Our CWIP balance for Darien was $183.8 million as of December 31, 2023.

2023 Form 10-K 76 Wisconsin Electric Power Company

NOTE 10—ASSET RETIREMENT OBLIGATIONS

We have recorded AROs primarily for asbestos abatement at certain generation and substation facilities; the removal and dismantlement of a biomass generation facility; the dismantling of wind and solar generation projects; and the closure of CCR landfills at our generation facilities. We establish regulatory assets and liabilities to record the differences between ongoing expense recognition under the ARO accounting rules and the ratemaking practices for retirement costs authorized by the PSCW.

On our balance sheets, AROs are recorded within other long-term liabilities. The following table shows changes to our AROs during the years ended December 31:

(in millions)	2023			2022		2021
Balance as of January 1	$	71.7		$	70.8	$	54.5
Accretion	1.8			1.8		1.7
Additions	4.4		(1)	—		—
Revisions to estimated cash flows	(4.5)		(2)	0.3		17.3		(3)
Liabilities settled	(0.3)			(1.2)		(2.7)
Balance as of December 31	$	73.1		$	71.7	$	70.8

(1)    AROs increased primarily as a result of AROs being recorded for the legal requirement to dismantle, at retirement, the Badger Hollow II solar generation project.

(2)    AROs decreased primarily due to revisions made to removal estimates for fly ash landfills and changes in settlement timing of electric substation asbestos liabilities.

(3)     AROs increased primarily due to revisions made to removal estimates for Blue Sky, Glacier Hills, and Montfort.

NOTE 11—COMMON EQUITY

Stock-Based Compensation

The following table summarizes our pre-tax stock-based compensation expense, including amounts allocated from WBS, and the related tax benefit recognized in income for the years ended December 31:

(in millions)	2023			2022		2021
Stock options	$	1.9		$	2.4	$	2.3
Restricted stock	2.3			2.3		2.2
Performance units	(0.9)		(1)	8.5		1.7
Stock-based compensation expense	$	3.3		$	13.2	$	6.2
Related tax benefit	$	0.9		$	3.6	$	1.7

(1)    The reduction in expense was due to a decrease in the fair value of the outstanding performance units.

Stock-based compensation costs capitalized during 2023, 2022, and 2021 were not significant.

Stock Options

The following is a summary of our employees' WEC Energy Group stock option activity during 2023:

Stock Options	Number of Options	Weighted-Average Exercise Price		Weighted-Average Remaining Contractual Life (in years)	Aggregate Intrinsic Value (in millions)
Outstanding as of January 1, 2023	475,509	$	70.63
Granted	30,495	93.69
Exercised	(57,704)	43.70
Outstanding as of December 31, 2023	448,300	75.67		5.1	$	5.6
Exercisable as of December 31, 2023	332,592	69.45		4.2	$	5.6

2023 Form 10-K 77 Wisconsin Electric Power Company

The aggregate intrinsic value of outstanding and exercisable options in the above table represents the total pre-tax intrinsic value that would have been received by the option holders had they exercised all of their options on December 31, 2023. This is calculated as the difference between WEC Energy Group's closing stock price on December 31, 2023, and the option exercise price, multiplied by the number of in-the-money stock options. The intrinsic value of options exercised during the years ended December 31, 2023, 2022, and 2021 was $2.5 million, $6.1 million, and $2.9 million, respectively. Cash received by WEC Energy Group from exercises of its options by our employees was $2.5 million, $4.3 million, and $2.6 million during the years ended December 31, 2023, 2022, and 2021, respectively. The actual tax benefit from option exercises for the same years was approximately $0.7 million, $1.7 million, and $0.8 million, respectively.

As of December 31, 2023, we expected to recognize approximately $0.5 million of unrecognized compensation cost related to unvested and outstanding WEC Energy Group stock options over the next 1.6 years on a weighted-average basis.

During the first quarter of 2024, the Compensation Committee awarded 33,081 non-qualified WEC Energy Group stock options with an exercise price of $85.05 and a weighted-average grant date fair value of $16.20 per option to certain of our officers and other key employees under its normal schedule of awarding long-term incentive compensation.

Restricted Shares

The following is a summary of our employees' WEC Energy Group restricted stock activity during 2023:

Restricted Shares	Number of Shares	Weighted-Average Grant Date Fair Value
Outstanding and unvested as of January 1, 2023	7,208	$	93.97
Granted	4,544	93.69
Released	(3,358)	93.21
Forfeited	(223)	94.13
Outstanding and unvested as of December 31, 2023	8,171	94.12

The intrinsic value of WEC Energy Group restricted stock held by our employees that was released was $0.3 million for the year ended December 31, 2023, and $0.4 million for each of the years ended December 31, 2022 and 2021. The actual tax benefit from released restricted shares was $0.1 million for each of the years ended December 31, 2023, 2022, and 2021.

As of December 31, 2023, we expected to recognize approximately $1.1 million of unrecognized compensation cost related to unvested and outstanding WEC Energy Group restricted stock over the next 1.7 years on a weighted-average basis.

During the first quarter of 2024, the Compensation Committee awarded 7,754 WEC Energy Group restricted shares to our officers and other key employees under its normal schedule of awarding long-term incentive compensation. The grant date fair value of these awards was $85.05 per share.

Performance Units

During 2023, 2022, and 2021, the Compensation Committee awarded 19,780; 21,158; and 18,138 WEC Energy Group performance units, respectively, to our officers and other key employees under the WEC Energy Group Performance Unit Plan.

Performance units with an intrinsic value of $1.2 million, $2.8 million, and $3.1 million were settled during 2023, 2022, and 2021, respectively. The actual tax benefit from the distribution of performance units for the same years was $0.3 million, $0.7 million, and $0.7 million, respectively.

At December 31, 2023, our employees held 53,116 WEC Energy Group performance units, including dividend equivalents. A liability of $1.3 million was recorded on our balance sheet at December 31, 2023 related to these outstanding units. As of December 31, 2023, we expected to recognize approximately $5.2 million of unrecognized compensation cost related to unvested and outstanding WEC Energy Group performance units over the next 1.9 years on a weighted-average basis.

During the first quarter of 2024, performance units held by our employees with an intrinsic value of $0.1 million were settled. The actual tax benefit from the distribution of these awards was not significant. In January 2024, the Compensation Committee also

2023 Form 10-K 78 Wisconsin Electric Power Company

awarded 25,242 WEC Energy Group performance units to our officers and other key employees under its normal schedule of awarding long-term incentive compensation.

Restrictions

Various financing arrangements and regulatory requirements impose certain restrictions on our ability to transfer funds to WEC Energy Group in the form of cash dividends, loans, or advances. In addition, Wisconsin law prohibits us from making loans to or guaranteeing obligations of WEC Energy Group or its subsidiaries.

In accordance with our most recent rate order, we may not pay common dividends above the test year forecasted amount reflected in our rate case, if it would cause our average common equity ratio, on a financial basis, to fall below our authorized level of 53.0%. A return of capital in excess of the test year amount can be paid by us at the end of the year provided that our average common equity ratio does not fall below the authorized level.

We may not pay common dividends to WEC Energy Group under our Restated Articles of Incorporation if any dividends on our outstanding preferred stock have not been paid. In addition, pursuant to the terms of our 3.60% Serial Preferred Stock, our ability to declare common dividends would be limited to 75% or 50% of net income during a 12-month period if our common stock equity to total capitalization, as defined in the preferred stock designation, is less than 25% and 20%, respectively.

See Note 13, Short-Term Debt and Lines of Credit, for a discussion of certain financial covenants related to our short-term debt obligations.

As of December 31, 2023, our retained earnings were fully restricted.

We do not believe that these restrictions will materially affect our operations or limit any dividend payments in the foreseeable future.

NOTE 12—PREFERRED STOCK

The following table shows preferred stock authorized and outstanding at December 31, 2023 and 2022:

(in millions, except share and per share amounts)	Shares Authorized	Shares Outstanding	Redemption Price Per Share		Total
$100 par value, Six Per Cent. Preferred Stock	45,000	44,498	$	—	$	4.4
$100 par value, Serial Preferred Stock 3.60% Series	2,286,500	260,000	101		26.0
$25 par value, Serial Preferred Stock	5,000,000	—	—		—
Total					$	30.4

NOTE 13—SHORT-TERM DEBT AND LINES OF CREDIT

The following table shows our short-term borrowings and their corresponding weighted-average interest rates as of December 31:

(in millions, except percentages)	2023			2022
Commercial paper
Amount outstanding at December 31	$	360.8		$	460.7
Average interest rate on amounts outstanding at December 31	5.48		%	4.59		%

Our average amount of commercial paper borrowings based on daily outstanding balances during 2023 was $109.9 million, with a weighted-average interest rate during the period of 5.19%.

We have entered into a bank back-up credit facility to maintain short-term credit liquidity which, among other terms, requires us to maintain, subject to certain exclusions, a total funded debt to capitalization ratio of 65% or less. As of December 31, 2023, we were in compliance with this ratio.

2023 Form 10-K 79 Wisconsin Electric Power Company

The information in the table below relates to our revolving credit facility used to support our commercial paper borrowing program, including remaining available capacity under this facility as of December 31:

(in millions)	Maturity	2023
Revolving credit facility	September 2026	$	500.0
Less:
Letters of credit issued inside credit facility		1.0
Commercial paper outstanding		360.8
Available capacity under existing agreement		$	138.2

This facility has a renewal provision for two extensions, subject to lender approval. Each extension is for a period of one year.

Our bank back-up credit facility contains customary covenants, including certain limitations on our ability to sell assets. The credit facility also contains customary events of default, including payment defaults, material inaccuracy of representations and warranties, covenant defaults, bankruptcy proceedings, certain judgments, Employee Retirement Income Security Act of 1974 defaults and change of control.

NOTE 14—LONG-TERM DEBT

The following table is a summary of our long-term debt outstanding as of December 31:

(in millions)	Interest Rate	Year Due	2023		2022
WE Debentures (unsecured)	2.05%	2024	$	300.0	$	300.0
	3.10%	2025	250.0		250.0
	6.50%	2028	150.0		150.0
	1.70%	2028	300.0		300.0
	4.75%	2032	500.0		500.0
	5.625%	2033	335.0		335.0
	5.70%	2036	300.0		300.0
	3.65%	2042	250.0		250.0
	4.25%	2044	250.0		250.0
	4.30%	2045	250.0		250.0
	4.30%	2048	300.0		300.0
	6.875%	2095	100.0		100.0
WEPCo Environmental Trust (secured, nonrecourse) (1) (2)	1.578%	2024-2035	97.0		105.9
Total			3,382.0		3,390.9
Unamortized debt issuance costs			(13.0)		(14.9)
Unamortized discount, net			(14.6)		(15.6)
Total long-term debt, including current portion			3,354.4		3,360.4
Current portion of long-term debt			(309.0)		(8.9)
Total long-term debt			$	3,045.4	$	3,351.5

(1)    WEPCo Environmental Trust’s ETBs are secured by a pledge of and lien on environmental control property, which includes the right to impose, collect and receive a non-bypassable environmental control charge paid by all of our retail electric distribution customers, the right to obtain true-up adjustments of the environmental control charge, and all revenues or other proceeds arising from those rights and interests. See Note 21, Variable Interest Entities, for more information.

(2)    The long-term debt of WEPCo Environmental Trust requires periodic principal payments.

We amortize debt premiums, discounts, and debt issuance costs over the life of the debt using the straight-line method and we include the costs in interest expense.

2023 Form 10-K 80 Wisconsin Electric Power Company

The following table shows the future maturities of our long-term debt outstanding as of December 31, 2023:

(in millions)
2024	$	309.0
2025	259.2
2026	9.3
2027	9.5
2028	459.6
Thereafter	2,335.4
Total	$	3,382.0

Our long-term debt obligations contain covenants related to payment of principal and interest when due and various other obligations. Failure to comply with these covenants could result in an event of default, which could result in the acceleration of outstanding debt obligations.

NOTE 15—LEASES

Obligations Under Operating Leases

We have recorded right of use assets and lease liabilities associated with the following operating leases:

•Land we are leasing related to our Rothschild biomass plant through June 2051.

•Rail cars we are leasing to transport coal to various generating facilities through June 2027.

•Land we are leasing related to our utility solar generation projects through April 2073.

The operating leases generally require us to pay property taxes, insurance premiums, and operating and maintenance costs associated with the leased property. Certain of our leases contain options for early termination or to renew past the initial term, as set forth in the lease agreements. These options are included in our calculation of the lease obligations if it is reasonably certain that they will be exercised.

Obligations Under Finance Leases

In accordance with ASC Subtopic 980-842, Regulated Operations – Leases (Subtopic 980-842), the timing of expense recognition associated with our finance leases is modified to conform to the rate treatment. Amortization of the right-of-use asset is modified so that the total of the imputed interest and amortization costs equals the lease expense that is allowed for rate-making purposes. The difference between this lease expense and the sum of imputed interest and unadjusted amortization costs calculated under Topic 842 is deferred as a regulatory asset on our balance sheets in accordance with Subtopic 980-842.

Power Purchase Commitment

In 1997, we entered into a 25-year PPA with LSP-Whitewater Limited Partnership. The contract, for 236.5 MWs of firm capacity from a natural gas-fired cogeneration facility, included zero minimum energy requirements. The PPA expired on May 31, 2022; however, in November 2021, we entered into a tolling agreement with LSP-Whitewater Limited Partnership that commenced on June 1, 2022. Concurrent with the execution of the tolling agreement, we entered into an asset purchase agreement to acquire a 50% ownership interest in the natural gas-fired cogeneration facility, and the acquisition closed effective January 1, 2023. See Note 2, Acquisitions, for more information. Both the PPA and the tolling agreement were accounted for as a finance lease prior to the acquisition.

Port Washington Generating Station

We are leasing PWGS 1 and PWGS 2, two 545 MW natural gas-fired generation units, which were placed in service in July 2005 and May 2008, respectively, from We Power under PSCW approved leases. We are amortizing the leased units on a straight-line basis over the original 25-year term of the leases. The lease payments are expected to be recovered through our rates, as supported by Wisconsin's 2001 leased generation law.

The only variability associated with the PWGS lease payments relates to the potential for future changes in We Power's tax or interest rates, as the positive or negative impact of these changes is generally passed along to us, and subsequently to our

2023 Form 10-K 81 Wisconsin Electric Power Company

customers. Because variability in the lease payments is dependent upon a rate (interest rate or tax rate), the lease payments are considered unavoidable under Topic 842, and are included in the measurement of the right of use asset and lease liability.

When the PWGS 1 and PWGS 2 contracts expire in 2030 and 2033, respectively, we may, at our option and with proper notice, choose to renew one or both contracts for up to three consecutive renewal terms (each renewal term would approximate 80% of the then remaining economic useful life of the respective generation unit), purchase one or both generating facilities at fair market value, or allow the contracts to expire.

Elm Road Generating Station

We are leasing ER 1, ER 2, and the common facilities, which are also utilized by our OCPP generating units 5 through 8, from We Power under PSCW approved leases. We are amortizing the leased units on a straight-line basis over the 30-year term of the leases. ER 1 and ER 2 were placed in service in February 2010 and January 2011, respectively. The lease payments are expected to be recovered through our rates, as supported by Wisconsin's 2001 leased generation law.

The only variability associated with the ERGS lease payments relates to the potential for future changes in We Power's tax or interest rates, as the positive or negative impact of these changes are generally passed along to us, and subsequently to our customers. Because variability in the lease payments is dependent upon a rate (interest rate or tax rate), the lease payments are considered unavoidable under Topic 842, and are included in the measurement of the right of use asset and lease liability.

When the ER 1 and ER 2 contracts expire in 2040 and 2041, respectively, we may, at our option and with proper notice, choose to renew one or both contracts for up to three consecutive renewal terms (each renewal term would approximate 80% of the then remaining economic useful life of the respective generation unit), purchase one or both generating facilities at fair market value, or allow the contracts to expire.

Land Leases – Utility Solar Generation

We have entered into various land leases related to our investments in utility solar generation. Each lease has an initial term and one or more optional extensions. We expect the optional extensions to be exercised, and, as a result, all of the land leases are being amortized over an extended term of approximately 50 years. Once a solar project achieves commercial operation, the lease liability is remeasured to reflect the final total acres being leased. Our payments related to these leases are being recovered through rates.

2023 Form 10-K 82 Wisconsin Electric Power Company

Amounts Recognized in the Financial Statements and Other Information

The components of lease expense and supplemental cash flow information related to our leases for the years ended December 31 are as follows:

(in millions)	2023			2022			2021
Finance lease expense
Amortization of right of use assets (1)	$	77.5		$	74.2		$	68.1
Interest on lease liabilities (2)	329.5			334.3			341.2
Operating lease expense (3)	1.6			1.8			1.4
Total lease expense	$	408.6		$	410.3		$	410.7
Other information
Cash paid for amounts included in the measurement of lease liabilities
Operating cash flows for finance leases	$	329.5		$	334.3		$	341.2
Operating cash flows for operating leases	1.6			1.8			1.4
Financing cash flows for finance leases	77.0			73.6			67.5
Non-cash activities:
Right of use assets obtained in exchange for finance lease liabilities (4)	$	136.5		$	60.0		$	52.7
Right of use assets obtained in exchange for operating lease liabilities	2.3			—			0.3
Weighted-average remaining lease term – finance leases	16.2 years			16.5 years			16.9 years
Weighted-average remaining lease term – operating leases	24.9 years			27.0 years			28.5 years
Weighted-average discount rate – finance leases (5)	13.4		%	13.6		%	13.8		%
Weighted average discount rate – operating leases (5)	4.8		%	4.5		%	4.5		%

(1)    Amortization of right of use assets was included as a component of depreciation and amortization expense.

(2)    Interest on lease liabilities was included as a component of interest expense.

(3)    Operating lease expense was included as a component of other operation and maintenance expense.

(4)    Amounts are net of any reductions to right of use assets and finance lease liabilities resulting from remeasurements.

(5)    Because our operating leases and our power purchase commitment and solar land leases accounted for as finance leases do not provide an implicit rate of return, we used the fully collateralized incremental borrowing rates based upon information available for similarly rated companies in determining the present value of lease payments. For the PWGS and ERGS units that meet the definition of a finance lease, the rate implicit in the lease was readily determinable.

2023 Form 10-K 83 Wisconsin Electric Power Company

The following table summarizes our finance and operating lease right of use assets and obligations at December 31:

(in millions)	2023		2022		Balance Sheet Location
Right of use assets
Operating lease right of use assets, net	$	10.2	$	8.4	Other long-term assets
Finance lease right of use assets, net
Power purchase commitment (1)	$	—	$	38.3
PWGS	268.6		297.1
ERGS	1,362.0		1,335.8
Land leases – utility solar generation	92.4		67.9
Total finance lease right of use assets, net (2)	$	1,723.0	$	1,739.1	Property, plant, and equipment, net
Lease obligations
Current operating lease liabilities	$	0.8	$	0.6	Other current liabilities
Long-term operating lease liabilities	$	9.4	$	7.8	Other long-term liabilities
Current finance lease liabilities
Power purchase commitment (1)	$	—	$	36.3
PWGS	42.9		37.8
ERGS	44.9		38.2
Total current finance lease liabilities	$	87.8	$	112.3	Current portion of finance lease obligations
Long-term finance lease liabilities
PWGS	$	474.8	$	512.2
ERGS	2,177.8		2,118.8
Land leases – utility solar generation	99.6		71.3
Total long-term finance lease liabilities	$	2,752.2	$	2,702.3	Finance lease obligations

(1)    Effective January 1, 2023, we and WPS closed on the acquisition of Whitewater. See discussion above for more information.

(2)    Amounts are net of accumulated amortization of $1,483.8 million and $1,509.7 million at December 31, 2023 and 2022, respectively.

Future minimum lease payments under our operating and finance leases and the present value of our net minimum lease payments as of December 31, 2023, were as follows:

(in millions)	Total Operating Leases		PWGS		ERGS		Land Leases - Utility Solar Generation		Total Finance Leases
2024	$	1.3	$	102.8	$	314.0	$	3.4	$	420.2
2025	1.0		102.5		313.9		4.5		420.9
2026	1.0		102.4		313.9		4.6		420.9
2027	0.7		102.2		313.8		4.6		420.6
2028	0.5		102.2		313.7		4.7		420.6
Thereafter	13.9		302.0		3,614.2		347.5		4,263.7
Total minimum lease payments	18.4		814.1		5,183.5		369.3		6,366.9
Less: Interest	(8.2)		(296.4)		(2,960.8)		(269.7)		(3,526.9)
Present value of minimum lease payments	10.2		517.7		2,222.7		99.6		2,840.0
Less: Short-term lease liabilities	(0.8)		(42.9)		(44.9)		—		(87.8)
Long-term lease liabilities	$	9.4	$	474.8	$	2,177.8	$	99.6	$	2,752.2

As of February 22, 2024, we have not entered into any material leases that have not yet commenced.

2023 Form 10-K 84 Wisconsin Electric Power Company

NOTE 16—INCOME TAXES

Income Tax Expense

The following table is a summary of income tax expense for each of the years ended December 31:

(in millions)	2023		2022		2021
Current tax expense	$	122.0	$	81.0	$	90.3
Deferred income taxes, net	26.2		53.6		(30.7)
ITCs	(5.5)		(1.5)		(1.5)
Total income tax expense	$	142.7	$	133.1	$	58.1

Statutory Rate Reconciliation

The provision for income taxes for each of the years ended December 31 differs from the amount of income tax determined by applying the applicable United States statutory federal income tax rate to income before income taxes as a result of the following:

	2023				2022				2021
(in millions)	Amount		Effective Tax Rate		Amount		Effective Tax Rate		Amount		Effective Tax Rate
Statutory federal income tax	$	130.9	21.0	%	$	111.2	21.0	%	$	92.3	21.0	%
State income taxes net of federal tax benefit	37.4		6.0	%	33.1		6.3	%	28.2		6.4	%
Federal excess deferred tax amortization (1)	(20.8)		(3.3)	%	(23.2)		(4.4)	%	(23.2)		(5.3)	%
PTCs	(11.6)		(1.9)	%	(2.3)		(0.4)	%	(6.8)		(1.5)	%
AFUDC-Equity	(8.6)		(1.4)	%	(3.9)		(0.7)	%	(1.7)		(0.4)	%
Domestic production activities deferral	6.3		1.0	%	6.3		1.1	%	6.3		1.4	%
Federal excess deferred tax amortization – Wisconsin unprotected (2)	5.3		0.9	%	5.3		1.0	%	(42.7)		(9.7)	%
Other, net	3.8		0.6	%	6.6		1.2	%	5.7		1.3	%
Total income tax expense	$	142.7	22.9	%	$	133.1	25.1	%	$	58.1	13.2	%

(1)    The Tax Legislation required us to remeasure our deferred income taxes and we began to amortize the resulting excess protected deferred income taxes beginning in 2018 in accordance with normalization requirements. The decrease in income tax expense related to the amortization of the deferred tax benefits is offset by a decrease in revenue as the benefits are returned to customers, resulting in no impact on net income.

(2)    In accordance with the rate order received from the PSCW in December 2019, the majority of our net unprotected deferred tax benefits related to electric operations were amortized to reduce near-term impacts to our customers over a period of two years, beginning with 2020. Consistent with the same rate order, the net unprotected tax expense related to gas and steam operations continues to be amortized over a period of four years, which began in 2020. The increase (decrease) in income tax expense related to the amortization of the deferred taxes is offset by an increase (decrease) in revenue as amounts are either collected from or returned to customers, resulting in no impact on net income.

See Note 24, Regulatory Environment, for more information about the impact of the Tax Legislation and the Wisconsin rate order.

2023 Form 10-K 85 Wisconsin Electric Power Company

Deferred Income Tax Assets and Liabilities

The components of deferred income taxes as of December 31 were as follows:

(in millions)	2023		2022
Deferred tax assets
Tax gross up – regulatory items	$	103.4	$	110.3
Deferred revenues	103.9		106.5
Future tax benefits	7.1		10.1
Other	53.6		60.2
Total deferred tax assets	$	268.0	$	287.1
Deferred tax liabilities
Property-related	$	1,430.4	$	1,399.0
Deferred costs – plant retirements	186.2		198.0
Employee benefits and compensation	60.6		68.2
Deferred costs – SSR	37.5		40.9
Other	66.8		48.3
Total deferred tax liabilities	1,781.5		1,754.4
Deferred tax liability, net	$	1,513.5	$	1,467.3

Consistent with ratemaking treatment, deferred taxes in the table above are offset for temporary differences that have related regulatory assets and liabilities.

The components of net deferred tax assets associated with federal tax benefit carryforwards as of December 31, 2023 and 2022 are summarized in the tables below:

2023 (in millions)	Gross Value		Deferred Tax Effect		Earliest Year of Expiration
Future tax benefits as of December 31, 2023
Federal tax credit	$	—	$	7.1	2042
Balance as of December 31, 2023	$	—	$	7.1

2022 (in millions)	Gross Value		Deferred Tax Effect		Earliest Year of Expiration
Future tax benefits as of December 31, 2022
Federal tax credit	$	—	$	10.1	2041
Balance as of December 31, 2022	$	—	$	10.1

Unrecognized Tax Benefits

We had no unrecognized tax benefits at December 31, 2023 and 2022.

We do not expect any unrecognized tax benefits to affect our effective tax rate in periods after December 31, 2023.

For the years ended December 31, 2023, 2022, and 2021, we recognized no interest expense and no penalties related to unrecognized tax benefits in our income statements. At December 31, 2023 and 2022, we had no interest accrued and no penalties accrued related to unrecognized tax benefits on our balance sheets.

We do not anticipate any significant increases in the total amount of unrecognized tax benefits within the next 12 months.

Our primary tax jurisdictions include federal and the state of Wisconsin. With a few exceptions we are no longer subject to federal income tax examinations by the IRS for years prior to 2020. As of December 31, 2023, we were subject to examination by the Wisconsin taxing authority for tax years 2019 through 2023.

2023 Form 10-K 86 Wisconsin Electric Power Company

NOTE 17—FAIR VALUE MEASUREMENTS

The following tables summarize our financial assets and liabilities that were accounted for at fair value on a recurring basis, categorized by level within the fair value hierarchy:

	December 31, 2023
(in millions)	Level 1		Level 2		Level 3		Total
Derivative assets
Natural gas contracts	$	0.9	$	1.3	$	—	$	2.2
FTRs	—		—		2.5		2.5
Total derivative assets	$	0.9	$	1.3	$	2.5	$	4.7
Derivative liabilities
Natural gas contracts	$	16.1	$	3.1	$	—	$	19.2
Coal contracts	—		19.3		—		19.3
Total derivative liabilities	$	16.1	$	22.4	$	—	$	38.5

	December 31, 2022
(in millions)	Level 1		Level 2		Level 3		Total
Derivative assets
Natural gas contracts	$	1.6	$	2.5	$	—	$	4.1
FTRs	—		—		2.0		2.0
Coal contracts	—		32.7		—		32.7
Total derivative assets	$	1.6	$	35.2	$	2.0	$	38.8
Derivative liabilities
Natural gas contracts	$	29.3	$	0.7	$	—	$	30.0

The derivative assets and liabilities listed in the tables above include options, futures, physical commodity contracts, and other instruments used to manage market risks related to changes in commodity prices. They also include FTRs, which are used to manage electric transmission congestion costs in the MISO Energy Markets.

The following table summarizes the changes to derivatives classified as Level 3 in the fair value hierarchy at December 31:

(in millions)	2023		2022		2021
Balance at the beginning of the period	$	2.0	$	1.0	$	1.1
Purchases	8.1		7.6		3.1
Settlements	(7.6)		(6.6)		(3.2)
Balance at the end of the period	$	2.5	$	2.0	$	1.0

Fair Value of Financial Instruments

The following table shows the financial instruments included on our balance sheets that are not recorded at fair value:

	December 31, 2023				December 31, 2022
(in millions)	Carrying Amount		Fair Value		Carrying Amount		Fair Value
Preferred stock	$	30.4	$	21.4	$	30.4	$	22.7
Long-term debt, including current portion	3,354.4		3,255.4		3,360.4		3,143.2

The fair values of our long-term debt and preferred stock are categorized within Level 2 of the fair value hierarchy.

2023 Form 10-K 87 Wisconsin Electric Power Company

NOTE 18—DERIVATIVE INSTRUMENTS

Derivative assets and liabilities are included in the other current and other long-term line items on our balance sheets. The following table shows our derivative assets and derivative liabilities. None of the derivatives shown below were designated as hedging instruments.

	December 31, 2023				December 31, 2022
(in millions)	Derivative Assets		Derivative Liabilities		Derivative Assets		Derivative Liabilities
Current
Natural gas contracts	$	2.2	$	18.6	$	4.1	$	28.8
FTRs	2.5		—		2.0		—
Coal contracts	—		10.2		17.6		—
Total current	4.7		28.8		23.7		28.8
Long-term
Natural gas contracts	—		0.6		—		1.2
Coal contracts	—		9.1		15.1		—
Total long-term	—		9.7		15.1		1.2
Total	$	4.7	$	38.5	$	38.8	$	30.0

Realized gains and losses on derivatives are primarily recorded in cost of sales upon settlement; however, they may be subsequently deferred for future rate recovery or refund as the gains and losses are included in our fuel and natural gas cost recovery mechanisms. Our estimated notional sales volumes and realized gains and losses were as follows for the years ended:

	December 31, 2023			December 31, 2022			December 31, 2021
(in millions)	Volumes	Gains (Losses)		Volumes	Gains		Volumes	Gains
Natural gas contracts	68.5 Dth	$	(102.2)	59.7 Dth	$	86.6	69.2 Dth	$	50.8
FTRs	20.4 MWh	14.5		18.9 MWh	8.1		21.0 MWh	8.7
Total		$	(87.7)		$	94.7		$	59.5

At December 31, 2023 and 2022, we had posted cash collateral of $26.7 million and $46.7 million, respectively.

The following table shows derivative assets and derivative liabilities if derivative instruments by counterparty were presented net on our balance sheets:

	December 31, 2023					December 31, 2022
(in millions)	Derivative Assets		Derivative Liabilities			Derivative Assets		Derivative Liabilities
Gross amount recognized on the balance sheet	$	4.7	$	38.5		$	38.8	$	30.0
Gross amount not offset on the balance sheet	(1.3)		(16.5)		(1)	(1.8)		(29.5)		(2)
Net amount	$	3.4	$	22.0		$	37.0	$	0.5

(1)      Includes cash collateral posted of $15.2 million.

(2)      Includes cash collateral posted of $27.7 million.

NOTE 19—EMPLOYEE BENEFITS

Pension and Other Postretirement Employee Benefits

We participate in WEC Energy Group's defined benefit pension plans and OPEB plans that cover substantially all of our employees. We are responsible for our share of the plan assets and obligations. The benefits for a portion of these plans are funded through irrevocable trusts, as allowed for income tax purposes. Our balance sheets reflect only the liabilities associated with our past and current employees and our share of the plan assets and obligations. We also offer medical, dental, and life insurance benefits to active employees and their dependents. We expense the costs of these benefits as incurred.

Generally, employees who started with us after 1995 receive a benefit based on a percentage of their annual salary plus an interest credit, while employees who started before 1996 receive a benefit based upon years of service and final average salary.

2023 Form 10-K 88 Wisconsin Electric Power Company

Management employees hired after December 31, 2014, and certain new represented employees hired after May 1, 2017, receive an annual company contribution to their 401(k) savings plan instead of being enrolled in the defined benefit plans.

We use a year-end measurement date to measure the funded status of all of the pension and OPEB plans. Due to the regulated nature of our business, we have concluded that substantially all of the unrecognized costs resulting from the recognition of the funded status of the pension and OPEB plans qualify as a regulatory asset.

The following tables provide a reconciliation of the changes in our share of the plans' benefit obligations and fair value of assets:

	Pension Benefits				OPEB Benefits
(in millions)	2023		2022		2023		2022
Change in benefit obligation
Obligation at January 1	$	894.9	$	1,144.0	$	144.6	$	190.6
Service cost	10.3		13.4		2.6		3.9
Interest cost	47.1		32.6		7.7		5.6
Participant contributions	—		—		5.6		6.6
Net transfer from/to affiliates	(1.2)		4.7		(0.4)		—
Actuarial (gain) loss	29.1		(211.3)		19.5		(46.9)
Benefit payments	(79.4)		(88.5)		(18.7)		(19.0)
Federal subsidy on benefits paid	N/A		N/A		1.3		1.2
Transfer	—		—		1.2		2.6
Obligation at December 31	$	900.8	$	894.9	$	163.4	$	144.6
Change in fair value of plan assets
Fair value at January 1	$	940.7	$	1,136.9	$	211.3	$	255.7
Actual return on plan assets	68.9		(115.8)		17.7		(32.6)
Employer contributions net of plan transfer (1)	3.2		3.8		(42.9)		0.1
Participant contributions	—		—		5.6		6.6
Net transfer from/to affiliates	(1.2)		4.3		(0.2)		0.5
Benefit payments	(79.4)		(88.5)		(18.7)		(19.0)
Fair value at December 31	$	932.2	$	940.7	$	172.8	$	211.3
Funded status at December 31	$	31.4	$	45.8	$	9.4	$	66.7

(1)    Employer contribution includes a $43.0 million transfer out of the WEC Energy Group Retiree Welfare Plan, in 2023, associated with the overfunded position of this plan.

In 2023, we had actuarial losses related to our pension benefit obligations of $29.1 million and actuarial gains in 2022 of $211.3 million. The primary driver for the actuarial loss was the change in discount rate. Partially offsetting the loss in 2023, was higher than expected asset returns. The discount rate for our pension benefits was 5.20%, 5.50%, and 2.94% in 2023, 2022, and 2021, respectively.

In 2023, we had actuarial losses related to our OPEB benefit obligation of $19.5 million and actuarial gains in 2022 of $46.9 million. The primary driver for the actuarial loss was changes to medical trend assumptions and a lower discount rate in 2023. Partially offsetting the loss in 2023, was higher than expected asset returns. The discount rate for our OPEB benefits was 5.15%, 5.50%, and 2.95% in 2023, 2022, and 2021, respectively.

The amounts recognized on our balance sheets at December 31 related to the funded status of the benefit plans were as follows:

	Pension Benefits				OPEB Benefits
(in millions)	2023		2022		2023		2022
Pension and OPEB assets	$	61.6	$	76.6	$	9.4	$	66.7
Other long-term liabilities	30.2		30.8		—		—
Total net assets	$	31.4	$	45.8	$	9.4	$	66.7

The accumulated benefit obligation for all defined benefit pension plans was $900.0 million and $894.0 million as of December 31, 2023 and 2022, respectively.

2023 Form 10-K 89 Wisconsin Electric Power Company

The following table shows information for the pension plans with an accumulated benefit obligation in excess of plan assets. There were no plan assets related to these pension plans. Amounts presented are as of December 31:

(in millions)	2023		2022
Accumulated benefit obligation	$	30.0	$	30.6

The following table shows information for pension plans with a projected benefit obligation in excess of plan assets. There were no plan assets related to these pension plans. Amounts presented are as of December 31:

(in millions)	2023		2022
Projected benefit obligation	$	30.2	$	30.8

We do not have any OPEB plans with an accumulated benefit obligation in excess of plan assets.

The following table shows the amounts that had not yet been recognized in our net periodic benefit cost as of December 31:

	Pension Benefits				OPEB Benefits
(in millions)	2023		2022		2023		2022
Net regulatory assets (liabilities)
Net actuarial loss (gain)	$	342.1	$	326.7	$	(89.1)	$	(113.0)
Prior service credits	(1.9)		(2.0)		(0.4)		(1.3)
Total	$	340.2	$	324.7	$	(89.5)	$	(114.3)

The components of net periodic benefit cost (credit) (including amounts capitalized to our balance sheets) for the years ended December 31 were as follows:

	Pension Benefits						OPEB Benefits
(in millions)	2023		2022		2021		2023		2022		2021
Service cost	$	10.3	$	13.4	$	14.4	$	2.6	$	3.9	$	4.3
Interest cost	47.1		32.6		31.1		7.7		5.6		5.3
Expected return on plan assets	(64.3)		(71.4)		(70.3)		(13.4)		(17.7)		(16.9)
Amortization of prior service credit	(0.1)		(0.1)		(0.1)		(0.9)		(1.3)		(1.2)
Amortization of net actuarial loss (gain)	9.2		29.8		41.9		(8.7)		(12.1)		(10.9)
Net periodic benefit cost (credit)	$	2.2	$	4.3	$	17.0	$	(12.7)	$	(21.6)	$	(19.4)

Effective January 1, 2023, the PSCW approved escrow accounting for pension and OPEB costs. As a result, as of December 31, 2023, we recorded a $1.2 million regulatory liability for pension costs and a $5.3 million regulatory asset for OPEB costs. The above table does not reflect any adjustments for the creation of these regulatory assets and liabilities.

The weighted-average assumptions used to determine the benefit obligations for the plans were as follows for the years ended December 31:

	Pension Benefits		OPEB Benefits
	2023	2022	2023	2022
Discount rate	5.20%	5.50%	5.15%	5.50%
Rate of compensation increase	4.00%	4.00%	N/A	N/A
Interest credit rate	5.14%	5.14%	N/A	N/A
Assumed medical cost trend rate (Pre 65)	N/A	N/A	6.25%	6.50%
Ultimate trend rate (Pre 65)	N/A	N/A	5.00%	5.00%
Year ultimate trend rate is reached (Pre 65)	N/A	N/A	2031	2031
Assumed medical cost trend rate (Post 65)	N/A	N/A	6.55%	6.00%
Ultimate trend rate (Post 65)	N/A	N/A	5.00%	5.00%
Year ultimate trend rate is reached (Post 65)	N/A	N/A	2030	2031

2023 Form 10-K 90 Wisconsin Electric Power Company

The weighted-average assumptions used to determine the net periodic benefit cost for the plans were as follows for the years ended December 31:

	Pension Benefits
	2023	2022	2021
Discount rate	5.50%	2.94%	2.63%
Expected return on plan assets	6.50%	6.75%	6.75%
Rate of compensation increase	4.00%	4.00%	4.00%
Interest credit rate	5.14%	5.16%	5.16%

	OPEB Benefits
	2023	2022	2021
Discount rate	5.50%	2.95%	2.65%
Expected return on plan assets	6.50%	7.00%	7.00%
Assumed medical cost trend rate (Pre 65)	6.50%	5.70%	5.85%
Ultimate trend rate (Pre 65)	5.00%	5.00%	5.00%
Year ultimate trend rate is reached (Pre 65)	2031	2028	2028
Assumed medical cost trend rate (Post 65)	6.00%	5.72%	5.86%
Ultimate trend rate (Post 65)	5.00%	5.00%	5.00%
Year ultimate trend rate is reached (Post 65)	2031	2028	2028

WEC Energy Group consults with its investment advisors on an annual basis to help forecast expected long-term returns on plan assets by reviewing historical returns as well as calculating expected total trust returns using the weighted-average of long-term market returns for each of the major target asset categories utilized in the trust. For 2024, the expected return on asset assumption for the pension plan and OPEB plans is 6.50%.

Plan Assets

Current pension trust assets and amounts which are expected to be contributed to the trusts in the future are expected to be adequate to meet pension payment obligations to current and future retirees.

The Investment Trust Policy Committee oversees investment matters related to all of our funded benefit plans. The Committee works with external actuaries and investment consultants on an on-going basis to establish and monitor investment strategies and target asset allocations. Forecasted cash flows for plan liabilities are regularly updated based on annual valuation results. Target allocations are determined utilizing projected benefit payment cash flows and risk analyses of appropriate investments. They are intended to reduce risk, provide long-term financial stability for the plans and maintain funded levels which meet long-term plan obligations while preserving sufficient liquidity for near-term benefit payments.

Our pension trust target asset allocations are 25% equity investments, 55% fixed income investments, and 20% private equity and real estate investments. The OPEB trust target asset allocations are 45% equity investments, 45% fixed income investments, and 10% real estate investments. Equity securities include investments in large-cap, mid-cap, and small-cap companies. Fixed income securities include corporate bonds of companies from diversified industries, mortgage and other asset backed securities, commercial paper, and United States Treasuries.

Pension and OPEB plan investments are recorded at fair value. See Note 1(o), Fair Value Measurements, for more information regarding the fair value hierarchy and the classification of fair value measurements based on the types of inputs used.

2023 Form 10-K 91 Wisconsin Electric Power Company

The following tables provide the fair values of our investments by asset class:

	December 31, 2023
	Pension Plan Assets								OPEB Assets
(in millions)	Level 1		Level 2		Level 3		Total		Level 1		Level 2		Level 3		Total
Asset Class
Equity securities:
United States equity	$	57.4	$	—	$	—	$	57.4	$	17.3	$	—	$	—	$	17.3
International equity	51.4		—		—		51.4		16.3		—		—		16.3
Fixed income securities: (1)
United States bonds	—		404.1		—		404.1		13.4		52.4		—		65.8
International bonds	—		31.7		—		31.7		—		3.3		—		3.3
	$	108.8	$	435.8	$	—	$	544.6	$	47.0	$	55.7	$	—	$	102.7
Investments measured at net asset value:
Equity securities							137.9								34.4
Fixed income securities							0.1								6.3
Other							249.6								29.4
Total							$	932.2							$	172.8

(1)    This category represents investment grade bonds of United States and foreign issuers denominated in United States dollars from diverse industries.

	December 31, 2022
	Pension Plan Assets								OPEB Assets
(in millions)	Level 1		Level 2		Level 3		Total		Level 1		Level 2		Level 3		Total
Asset Class
Equity securities:
United States equity	$	69.5	$	—	$	—	$	69.5	$	23.6	$	—	$	—	$	23.6
International equity	60.8		—		—		60.8		20.2		—		—		20.2
Fixed income securities: (1)
United States bonds	—		419.2		—		419.2		25.8		45.8		—		71.6
International bonds	—		35.5		—		35.5		—		3.9		—		3.9
	$	130.3	$	454.7	$	—	$	585.0	$	69.6	$	49.7	$	—	$	119.3
Investments measured at net asset value:
Equity securities							139.7								47.3
Fixed income securities							—								12.7
Other							216.0								32.0
Total							$	940.7							$	211.3

(1)    This category represents investment grade bonds of United States and foreign issuers denominated in United States dollars from diverse industries.

Cash Flows

We expect to contribute $3.2 million to the pension plans and $0.2 million to the OPEB plans in 2024, dependent upon various factors affecting us, including our liquidity position and possible tax law changes.

2023 Form 10-K 92 Wisconsin Electric Power Company

The following table shows the payments, reflecting expected future service, that we expect to make for pension and OPEB over the next 10 years:

(in millions)	Pension Benefits		OPEB Benefits
2024	$	86.9	$	11.5
2025	80.3		11.3
2026	79.6		11.3
2027	76.0		11.5
2028	73.4		11.6
2029-2033	331.3		58.9

Savings Plans

WEC Energy Group sponsors 401(k) savings plans that allow substantially all of our full-time employees to contribute a portion of their pre-tax and/or after-tax income in accordance with plan-specified guidelines. A percentage of employee contributions are matched by us through a contribution into the employee's savings plan account, up to certain limits. The 401(k) savings plans include an Employee Stock Ownership Plan. Certain employees receive an employer retirement contribution, which amounts are contributed to an employee's savings plan account based on the employee's wages. Total costs incurred under all of these plans were $15.5 million, $14.2 million, and $12.3 million in 2023, 2022, and 2021, respectively.

NOTE 20—SEGMENT INFORMATION

We use net income attributed to common shareholder to measure segment profitability and to allocate resources to our business. At December 31, 2023, we reported two segments, our utility segment and our other segment, which are described below.

Our utility segment includes our electric utility operations, including steam operations, and our natural gas utility operations.

•Our electric utility operations are engaged in the generation, distribution, and sale of electricity to customers in southeastern Wisconsin (including metropolitan Milwaukee), east central Wisconsin, and northern Wisconsin. In addition, our steam operations produce, distribute, and sell steam to customers in metropolitan Milwaukee.

•Our natural gas utility operations are engaged in the purchase, distribution, and sale of natural gas to retail customers as well as the transportation of customer-owned natural gas in southeastern, east central, and northern Wisconsin.

No significant items were reported in the other segment during the twelve months ended December 31, 2023, 2022, and 2021.

All of our operations and assets are located within the United States.

NOTE 21—VARIABLE INTEREST ENTITIES

The primary beneficiary of a VIE must consolidate the entity's assets and liabilities. In addition, certain disclosures are required for significant interest holders in VIEs.

We assess our relationships with potential VIEs, such as our coal suppliers, natural gas suppliers, coal transporters, natural gas transporters, and other counterparties related to PPAs, investments, and joint ventures. In making this assessment, we consider, along with other factors, the potential that our contracts or other arrangements provide subordinated financial support, the obligation to absorb the entity's losses, the right to receive residual returns of the entity, and the power to direct the activities that most significantly impact the entity's economic performance.

WEPCo Environmental Trust Finance I, LLC

In November 2020, the PSCW issued a financing order approving the securitization of $100 million of undepreciated environmental control costs related to our retired Pleasant Prairie power plant, the carrying costs accrued on the $100 million during the securitization process, and the related financing fees. The financing order also authorized us to form WEPCo Environmental Trust, a bankruptcy-remote special purpose entity, for the sole purpose of issuing ETBs to recover the costs approved in the financing order. WEPCo Environmental Trust is our wholly owned subsidiary.

2023 Form 10-K 93 Wisconsin Electric Power Company

In May 2021, WEPCo Environmental Trust issued ETBs and used the proceeds to acquire environmental control property from us. The environmental control property is recorded as a regulatory asset on our balance sheets and includes the right to impose, collect, and receive a non-bypassable environmental control charge from our retail electric distribution customers until the ETBs are paid in full and all financing costs have been recovered. The ETBs are secured by the environmental control property. Cash collections from the environmental control charge and funds on deposit in trust accounts are the sole sources of funds to satisfy the debt obligation. The bondholders do not have any recourse to us or any of our affiliates.

We act as the servicer of the environmental control property on behalf of WEPCo Environmental Trust and are responsible for metering, calculating, billing, and collecting the environmental control charge. As necessary, we are authorized to implement periodic adjustments of the environmental control charge. The adjustments are designed to ensure the timely payment of principal, interest, and other ongoing financing costs. We remit all collections of the environmental control charge to WEPCo Environmental Trust's indenture trustee.

WEPCo Environmental Trust is a VIE primarily because its equity capitalization is insufficient to support its operations. As described above, we have the power to direct the activities that most significantly impact WEPCo Environmental Trust's economic performance. Therefore, we are considered the primary beneficiary of WEPCo Environmental Trust, and consolidation is required.

The following table summarizes the impact of WEPCo Environmental Trust on our balance sheet:

(in millions)	December 31, 2023		December 31, 2022
Assets
Other current assets (restricted cash)	$	0.8	$	3.0
Regulatory assets	85.9		92.4
Other long-term assets (restricted cash)	0.6		0.6
Liabilities
Current portion of long-term debt	9.0		8.9
Other current liabilities (accrued interest)	0.1		0.1
Long-term debt	85.3		94.1

Power Purchase Commitment

On May 31, 2022, our PPA with LSP-Whitewater Limited Partnership that represented a variable interest expired. This agreement was for 236.5 MWs of firm capacity from a natural gas-fired cogeneration facility, and we accounted for it as a finance lease.

In November 2021, we entered into a tolling agreement with LSP-Whitewater Limited Partnership that commenced on June 1, 2022, upon the expiration of the PPA. Concurrent with the execution of the tolling agreement, we, along with WPS, entered into an agreement to purchase the natural gas-fired cogeneration facility. This asset purchase agreement was approved by the PSCW in December 2022, and the acquisition closed effective January 1, 2023. In accordance with the purchase agreement, we acquired a 50% ownership interest. See Note 2, Acquisitions, for more information on the acquisition of this facility. The tolling agreement represented a variable interest until the facility was acquired since its terms were substantially similar to the terms of the PPA. Based on the risks of the entity, including operations, maintenance, dispatch, financing, fuel costs, and other factors, we were not the primary beneficiary of the entity. We did not hold an equity or debt interest in the entity, and there was no residual guarantee associated with the tolling agreement. Similar to the PPA, we accounted for the tolling agreement as a finance lease.

NOTE 22—COMMITMENTS AND CONTINGENCIES

We have significant commitments and contingencies arising from our operations, including those related to unconditional purchase obligations, environmental matters, and enforcement and litigation matters.

Unconditional Purchase Obligations

We have obligations to distribute and sell electricity and natural gas to our customers and expect to recover costs related to these obligations in future customer rates. In order to meet these obligations, we routinely enter into long-term purchase and sale commitments for various quantities and lengths of time.

2023 Form 10-K 94 Wisconsin Electric Power Company

The following table shows our minimum future commitments related to these purchase obligations as of December 31, 2023:

				Payments Due By Period
(in millions)	Date Contracts Extend Through	Total Amounts Committed		2024		2025		2026		2027		2028		Later Years
Electric utility:
Nuclear	2033	$	6,280.6	$	600.3	$	634.5	$	681.6	$	730.4	$	782.6	$	2,851.2
Coal supply and transportation	2026	354.9		247.9		94.2		12.8		—		—		—
Purchased power	2051	29.2		3.6		2.3		2.4		2.4		2.5		16.0
Natural gas utility supply and transportation	2048	460.8		68.2		39.9		33.2		28.6		25.1		265.8
Total		$	7,125.5	$	920.0	$	770.9	$	730.0	$	761.4	$	810.2	$	3,133.0

Environmental Matters

Consistent with other companies in the energy industry, we face significant ongoing environmental compliance and remediation obligations related to current and past operations. Specific environmental issues affecting us include, but are not limited to, current and future regulation of air emissions such as SO2, NOx, fine particulates, mercury, and GHGs; water intake and discharges; management of coal combustion products such as fly ash; and remediation of impacted properties, including former manufactured gas plant sites.

We have continued to pursue a proactive strategy to manage our environmental compliance obligations, including:

•the development of additional sources of renewable electric energy supply, battery storage, and natural gas and LNG storage facilities;

•the addition of improvements for water quality matters such as treatment technologies to meet regulatory discharge limits and improvements to our cooling water intake systems;

•the addition of emission control equipment to existing facilities to comply with ambient air quality standards and federal clean air rules;

•the protection of wetlands and waterways, biodiversity including threatened and endangered species, and cultural resources associated with utility construction projects;

•the retirement of older coal-fired power plants and conversion to modern, efficient, natural gas generation, super-critical pulverized coal generation, and/or replacement with renewable generation;

•the beneficial use of ash and other products from coal-fired and biomass generating units;

•the remediation of former manufactured gas plant sites;

•the reduction of methane emissions across our natural gas distribution system by upgrading infrastructure; and

•the reporting of GHG emissions to comply with federal clean air rules.

Air Quality

Cross State Air Pollution Rule – Good Neighbor Plan

In March 2023, the EPA issued its final Good Neighbor Plan, which became effective in August 2023 and requires significant reductions in ozone-forming emissions of NOx from power plants and industrial facilities. After review of the final rule, we believe that we are well positioned to meet the requirements.

Our RICE units in Wisconsin are not currently subject to the final rule as each unit is less than 25 MWs. To the extent we use RICE engines for natural gas distribution operations, those engines not part of an LDC are subject to the emission limits and operational requirements of the rule beginning in 2026. The EPA has exempted LDCs from the final rule.

Mercury and Air Toxics Standards

In 2012, the EPA issued the MATS to limit emissions of mercury, acid gases, and other hazardous air pollutants. In April 2023, the EPA issued the pre-publication version of a proposed rule to strengthen and update MATS to reflect recent developments in control technologies and performance of coal and oil-fired units. The EPA proposed three revisions including a proposal to lower the PM

2023 Form 10-K 95 Wisconsin Electric Power Company

limit from 0.03 lb/MMBtu to 0.01 lb/MMBtu. The EPA also sought comments on an even lower limit of 0.006 lb/MMBtu. Adoption of either of these lower limits could have an adverse effect on our operations.

National Ambient Air Quality Standards

Ozone

After completing its review of the 2008 ozone standard, the EPA released a final rule in October 2015, creating a more stringent standard than the 2008 NAAQS. The 2015 ozone standard lowered the 8-hour limit for ground-level ozone. In November 2022, the EPA's 2022 CASAC Ozone Review Panel issued a draft report supporting the reconsideration of the 2015 standard. The EPA staff initially issued a draft Policy Assessment in March 2023 that supported the reconsideration, however, in August 2023 it announced that it is instead restarting its ozone standard evaluation. The EPA has indicated it plans to release its Integrated Review Plan in fall 2024. This new review is anticipated to take 3 to 5 years to complete.

In February 2022, revisions to the Wisconsin Administrative Code to adopt the 2015 standard were finalized. The amended regulations incorporated by reference the federal air pollution monitoring requirements related to the standard. The WDNR submitted the rule updates as a SIP revision to the EPA, which the EPA approved in February 2023.

In April 2022, the EPA proposed to find that the Milwaukee, Sheboygan, and Chicago, IL-IN-WI nonattainment areas did not meet the marginal attainment deadline of August 2021 and should be adjusted to "moderate" nonattainment status for the 2015 standard. In October 2022, the EPA published its final reclassifications from "marginal" to "moderate" for these areas, effective November 7, 2022. Accordingly, the WDNR submitted a SIP revision to the EPA in December 2022 to address the moderate nonattainment status.

In October 2023, the EPA found that 11 states, including Wisconsin, failed to submit timely SIP revisions to address nonattainment areas classified as "moderate" for the 2015 standard. This action triggered a 24-month deadline for states to get their SIP approved or the EPA will issue a federal implementation plan. Additionally, offset sanctions will take effect in 18 months if the SIP is not approved. The offset sanctions impact volatile organic compound and NOx emissions from new or modified sources in the nonattainment areas.

We believe that we are well positioned to meet the requirements associated with the 2015 ozone standard and do not expect to incur significant costs to comply with the associated state and federal rules.

Particulate Matter

In December 2020, the EPA completed its 5-year review of the 2012 annual and 24-hour standards for fine PM and determined that no revisions were necessary to the current annual standard of 12 µg/m3 or the 24-hour standard of 35 µg/m3. All counties within our service territory are in attainment with the current 2012 standards. Under the Biden Administration's policy review, the EPA concluded that the scientific evidence and information from the December 2020 determination supports revising the level of the annual standard for the PM NAAQS to below the current level of 12 µg/m3, while retaining the 24-hour standard. In January 2023, the EPA announced its proposed decision to revise the primary (health-based) annual PM2.5 standard from its current level of 12 µg/m3 to within the range of 9 to 10 µg/m3. The EPA also proposed not to change the current secondary (welfare-based) annual PM2.5 standard, primary and secondary 24-hour PM2.5 standards, and primary and secondary PM10 standards. The EPA did, however, take comments on the full range (between 8 and 11 µg/m3) included in the CASAC's latest report. The EPA finalized the rule on February 7, 2024 and lowered the primary annual PM2.5 level to 9 µg/m3, which could cause some nonattainment areas that may affect permitting at our facilities. The secondary and 24-hour standards remain unchanged. The EPA will designate areas as attainment and nonattainment with the new standard by early 2026. The WDNR will need to draft and submit a SIP for the EPA's approval.

Climate Change

In May 2023, the EPA proposed GHG performance standards for existing fossil-fired steam generating and gas combustion units and also proposed to repeal the Affordable Clean Energy rule, which had replaced the Clean Power Plan. For coal plants, no standards would apply under the proposed version of the rule until 2032, and after 2032 the applicable standard would depend on the unit's retirement date. For combined cycle natural gas plants above a 50% capacity factor, the proposed rule is highly dependent on the use of hydrogen as an alternative fuel, and on carbon capture technology. For simple cycle natural gas-fired combustion turbines, the proposed version of the rule does not include applicable limits as long as the capacity factor is less than 20%. The new Weston

2023 Form 10-K 96 Wisconsin Electric Power Company

RICE project is not affected under the rule because each RICE unit is less than 25 MWs. We continue to evaluate the proposed rule to understand the impacts to our operations. A final rule is expected in the second quarter of 2024.

In May 2023, the EPA proposed to revise the NSPS for GHG emissions from new, modified, and reconstructed fossil-fueled power plants. The EPA is proposing two distinct 111(b) rules – one for natural gas-fired stationary combustion turbines and the other for coal-fired units. New stationary combustion turbine units would be divided into three subcategories based on their annual capacity factor – low load, intermediate load, and base load. Our RICE units are not affected by this rule since each unit is below 25 MWs. WEC Energy Group's ESG Progress Plan is heavily focused on reducing GHG emissions. The EPA has indicated that it anticipates a final rule in the second quarter of 2024.

The EPA released proposed regulations for the Mandatory Greenhouse Gas Reporting Rule, 40 CFR Part 98, in June 2022. In May 2023, the EPA released a supplementary proposal, which includes updates of the global warming potentials to determine CO2 equivalency for threshold reporting and the addition of a new section regarding energy consumption. The proposed revisions could impact the reporting required for our electric generation facilities and LDC. In August 2023, the EPA also issued its proposed updates to amend reporting requirements for petroleum and natural gas systems, with an anticipated final rule to be issued in early 2024. We are currently evaluating the potential impact of the proposed rule, if any, on our operations.

WEC Energy Group's ESG Progress Plan includes the retirement of older, fossil-fueled generation, to be replaced with zero-carbon-emitting renewables and clean natural gas-fueled generation. We have already retired approximately 1,500 MWs of fossil-fueled generation since the beginning of 2018. WEC Energy Group expects to retire approximately 1,800 MWs of additional fossil-fueled generation by the end of 2031, which includes the planned retirements in 2024-2025 of OCPP Units 5-8. See Note 8, Property, Plant, and Equipment, for more information related to these planned power plant retirements. In May 2021, WEC Energy Group announced goals to achieve reductions in carbon emissions from its electric generation fleet by 60% by the end of 2025 and by 80% by the end of 2030, both from a 2005 baseline. WEC Energy Group expects to achieve these goals by continuing to make operating refinements, retiring less efficient generating units, and executing its capital plan. Over the longer term, the target for WEC Energy Group's generation fleet is to be net carbon neutral by 2050.

WEC Energy Group also continues to reduce methane emissions by improving its natural gas distribution systems, and has set a target across its natural gas distribution operations to achieve net-zero methane emissions by the end of 2030. WEC Energy Group plans to achieve its net-zero goal through an effort that includes both continuous operational improvements and equipment upgrades, as well as the use of RNG throughout its utility systems.

Water Quality

Clean Water Act Cooling Water Intake Structure Rule

The EPA issued a final regulation under Section 316(b) of the CWA that became effective in October 2014 and requires the location, design, construction, and capacity of cooling water intake structures at existing power plants reflect the BTA for minimizing adverse environmental impacts. The rule applies to all of our existing generating facilities with cooling water intake structures, except for the ERGS units, which were permitted and received a final BTA determination under the rules governing new facilities.

Pursuant to a WDNR rule, which became effective in June 2020, the requirements of federal Section 316(b) of the CWA were incorporated into the Wisconsin Administrative Code. The WDNR applies this rule when establishing BTA requirements for cooling water intake structures at existing facilities. These BTA requirements are incorporated into WPDES permits for our facilities.

We have received a final BTA determination for VAPP. We have received interim BTA determinations for OCPP Units 5-8. We believe that existing technology installed at the OCPP facility meets the BTA requirements; however, depending on the timing of the permit reissuance, all four generating units at the OCPP may be retired prior to the WDNR making a final BTA decision, anticipated in 2025.

The WDNR reissued the WPDES permit for PWGS effective October 2023. This reissued permit includes a conditional BTA determination with conditions for the existing PWGS porous dike (rock breakwater) cooling water intake structure. We do not anticipate compliance with these conditions will result in a material impact on our financial condition or the efficiency of power plant operations.

2023 Form 10-K 97 Wisconsin Electric Power Company

Steam Electric Effluent Limitation Guidelines

The EPA's ELG rule, effective January 2016 and modified in 2020, revised the treatment technology requirements related to BATW and wet FGD wastewaters at existing coal-fueled facilities and created new requirements for several types of power plant wastewaters. The two new requirements that affect us relate to discharge limits for BATW and wet FGD wastewater. Although our power plant facilities already have advanced wastewater treatment technologies installed that meet many of the discharge limits established by this rule, certain facility modifications are necessary to meet the ELG rule requirements. Through 2023, compliance costs associated with the ELG rule required $97 million in capital investment. An $8 million BATW modification to OCPP Units 7 and 8 was completed and placed in-service in mid-2021, and in December 2021, the PSCW issued a Certificate of Authority approving the $89 million ERGS FGD wastewater treatment system modification. The BATW modifications did not require PSCW approval prior to construction. All of these ELG required projects were placed in-service ahead of WPDES permit deadlines.

In March 2023, the EPA issued the proposed "supplemental ELG rule." The rule would replace the existing 2020 ELG rule and, as proposed, would establish stricter limitations on: 1) BATW; 2) FGD wastewater; 3) CCR leachate; and 4) legacy wastewaters. The most significant proposed ELG rule change is a ZLD requirement for FGD wastewater. Under the proposed rule, this new ZLD requirement must be met by a date determined by the WDNR that is as soon as possible beginning 60 days following publication of the final rule, but no later than December 31, 2029.

The proposed rule would also create a subcategory for "early adopters" that have already installed a compliant biological treatment system by the date of the proposed rule. Early adopters would not be required to install further FGD wastewater treatment, provided the facility owner also agrees to permanently cease combustion of coal by December 31, 2032. Although the $89 million biological treatment system at ERGS is complete and was placed in service in December 2023 to meet the WPDES permit deadline, the timing of the project's completion did not comply with the deadline proposed by the EPA to qualify for the early adopter status. In addition, we do not believe that the biological treatment system would be compliant with the additional ZLD FGD wastewater treatment requirements as proposed. In May 2023, we submitted written comments to the EPA articulating these concerns, including the cost impact to our customers. The EPA has indicated that it anticipates issuing the final rule in the second quarter of 2024.

If the supplemental ELG rule is finalized as proposed, we anticipate that our coal-fueled facilities, including ER 1 and ER 2 that were built with ELG-compliant dry BA transport systems, will meet the BATW rule provisions.

The EPA also proposed requirements for legacy wastewaters and landfill leachate. We have reviewed the proposed requirements to determine potential costs and actions required for our facilities. We submitted comments to the EPA regarding these proposed requirements.

Waters of the United States

In January 2023, the EPA and the Army Corps (the agencies) together released a final rule effective in March 2023 that established standards for identifying which wetland or surface drainage features qualify as WOTUS based on its pre-2015 definition. The pre-2015 approach involved applying factors established through case law and agency precedents to determine whether a wetland or surface drainage feature is subject to federal jurisdiction.

In May 2023, in Sackett v. EPA, the Supreme Court issued a decision significantly narrowing federal jurisdiction over wetlands to "traditional navigable waters" and wetlands or other waters that have a "continuous surface connection" with a traditional navigable water.

In August 2023, the agencies revised the final rule to conform the definition of WOTUS to the Supreme Court's May 2023 Sackett decision. The conforming rule became effective upon publication in the Federal Register on September 8, 2023.

We anticipate this final rule revision based on the Sackett decision may lead to a decreased number of projects that require Army Corps federal wetland permits. This decision also may affect the administration of some state programs. At this point, our projects requiring federal permits are moving ahead, but we are monitoring these recent developments to better understand potential future impacts.

2023 Form 10-K 98 Wisconsin Electric Power Company

Land Quality

Manufactured Gas Plant Remediation

We have identified sites at which we or a predecessor company owned or operated a manufactured gas plant or stored manufactured gas. We have also identified other sites that may have been impacted by historical manufactured gas plant activities. We are responsible for the environmental remediation of these sites. We are also working with the state of Wisconsin in our investigation and remediation planning. These sites are at various stages of investigation, monitoring, remediation, and closure.

The future costs for detailed site investigation, future remediation, and monitoring are dependent upon several variables including, among other things, the extent of remediation, changes in technology, and changes in regulation. Historically, our regulators have allowed us to recover incurred costs, net of insurance recoveries and recoveries from potentially responsible parties, associated with the remediation of manufactured gas plant sites. Accordingly, we have established regulatory assets for costs associated with these sites.

We have established the following regulatory assets and reserves for manufactured gas plant sites as of December 31:

(in millions)	2023		2022
Regulatory assets	$	12.2	$	14.6
Reserves for future environmental remediation (1)	$	10.3	$	10.3

(1)    Recorded within other long-term liabilities on our balance sheets.

Coal Combustion Residuals Rule

The EPA issued a pre-publication proposed rule for CCR in May 2023 that would apply to landfills, historic fill sites, and projects where CCR was placed at a power plant site. As proposed, the rule would regulate previously exempt closed landfills.

We are actively engaged with our trade organizations and provided them information to include in their comments to the EPA. The EPA has indicated that it anticipates issuing a final rule in the second quarter of 2024. As proposed, the rule could have a material adverse impact on our coal ash landfills and require additional remediation that has not been required under the current state programs.

Renewables, Efficiency, and Conservation

Wisconsin Legislation

In 2005, Wisconsin enacted Act 141, which established a goal that 10% of all electricity consumed in Wisconsin be generated by renewable resources annually. We have achieved our required renewable energy percentage of 8.27% by constructing various wind parks, a solar park, a biomass facility, and by also relying on renewable energy purchases. We continue to review our renewable energy portfolio and acquire cost-effective renewables as needed to meet our requirements on an ongoing basis. The PSCW administers the renewable program related to Act 141, and we fund the program, along with other utilities, based on 1.2% of our annual retail operating revenues.

Enforcement and Litigation Matters

We are involved in legal and administrative proceedings before various courts and agencies with respect to matters arising in the ordinary course of business. Although we are unable to predict the outcome of these matters, management believes that appropriate reserves have been established and that final settlement of these actions will not have a material impact on our financial condition or results of operations.

2023 Form 10-K 99 Wisconsin Electric Power Company

NOTE 23—SUPPLEMENTAL CASH FLOW INFORMATION

Non-Cash Transactions

	Year Ended December 31
(in millions)	2023		2022		2021
Cash paid for interest, net of amount capitalized	$	463.8	$	449.2	$	460.8
Cash paid for income taxes, net (1)	99.1		88.0		88.0
Significant non-cash investing and financing transactions:
Accounts payable related to construction costs	71.8		89.1		42.4
Increase in receivables related to insurance proceeds	—		—		37.3
Liabilities accrued for software licensing agreement	—		3.1		—

(1)    Cash paid for income taxes in 2023 was net of $4.9 million of PTCs that were sold to a third party.

Restricted Cash

The statements of cash flows include our activity related to cash, cash equivalents, and restricted cash. The following table reconciles the cash, cash equivalents, and restricted cash amounts reported within the balance sheets at December 31 to the total of these amounts shown on the statements of cash flows:

(in millions)	2023		2022		2021
Cash and cash equivalents	$	6.1	$	6.1	$	—
Restricted cash included in other current assets	0.8		3.0		2.4
Restricted cash included in other long-term assets	0.6		38.6		0.6
Cash, cash equivalents, and restricted cash	$	7.5	$	47.7	$	3.0

Our restricted cash consisted of the following:

•Cash on deposit in a financial institution that is restricted to satisfy the requirements of a debt agreement at WEPCo Environmental Trust. See Note 21, Variable Interest Entities, for more information.

•Cash used during January 2023 to purchase a 50% interest in a natural gas-fired cogeneration facility located in Whitewater, Wisconsin. This cash was included in other long-term assets at December 31, 2022. See Note 2, Acquisitions, for more information on the purchase of this facility.

NOTE 24—REGULATORY ENVIRONMENT

2024 Limited Rate Case Re-Opener

In accordance with our rate order approved by the PSCW in December 2022, we filed a request with the PSCW in May 2023 for a limited electric and natural gas rate case re-opener. Our limited electric rate case re-opener included updated fuel costs and revenue requirements for the generation projects that were previously approved by the PSCW and were placed into service in 2023 or are expected to be placed into service in 2024. It also included the projected savings from the retirement of the OCPP Units 5 and 6, which are expected to be retired in May 2024. Our limited natural gas rate case re-opener reflected the additional revenue requirements associated with our previously approved LNG project that was placed into service in November 2023.

On December 20, 2023, the PSCW issued a final written order approving electric and natural gas rate increases, effective January 1, 2024. The final orders reflected the following:

2024 incremental rate increases
Electric (1)	$	82.2	million	/	2.5%
Gas	$	23.9	million	/	4.5%

(1)    Amount reflects the impact to our Wisconsin retail electric operations and includes the incremental increase from updated fuel costs.

Our ROE and common equity component average were not addressed in the limited rate case re-opener.

2023 Form 10-K 100 Wisconsin Electric Power Company

2023 and 2024 Rates

In April 2022, we filed a request with the PSCW to increase our retail electric, natural gas, and steam rates. Our request was updated in July 2022 to reflect new developments that impacted the original proposal. The requested increase in electric rates was driven by capital investments in new wind, solar, and battery storage; capital investments in natural gas generation; reliability investments, including grid hardening projects to bury power lines and strengthen our distribution system against severe weather; and changes in wholesale business with other utilities. Many of these investments had already been approved by the PSCW. The requested increase in natural gas rates primarily related to capital investments previously approved by the PSCW, including LNG storage for our natural gas distribution system.

In September 2022, we entered into a settlement agreement with certain intervenors to resolve most of the outstanding issues in our rate case; however, the PSCW declined to approve the settlement agreement. In December 2022, the PSCW issued a final written order approving electric, natural gas, and steam base rate increases, effective January 1, 2023. The final order reflected the following:

2023 base rate increase
Electric	$	283.5	million	/	9.1%
Gas	$	46.1	million	/	9.6%
Steam	$	7.6	million	/	35.3%
ROE	9.8%
Common equity component average on a financial basis	53.0%

In addition to the above, the final order included the following terms:

•We will keep our current earnings sharing mechanism, under which, if we earn above our authorized ROE: (i) we retain 100.0% of earnings for the first 15 basis points above the authorized ROE; (ii) 50.0% of the next 60 basis points is refunded to ratepayers; and (iii) 100.0% of any remaining excess earnings is required to be refunded to ratepayers.

•We were required to complete an analysis of alternative recovery scenarios for generating units that will be retired prior to the end of their useful life.

•We will not propose any changes to our real time pricing rates for large commercial and industrial electric customers through the end of 2024.

•We were required to lower monthly residential and small commercial electric customer fixed charges by $1.00 from previously authorized rates.

•We were required to offer an additional voluntary renewable energy pilot for commercial and industrial customers.

•We will continue to work with PSCW staff and other interested parties to develop alternative low income assistance programs. We, along with WPS, also collectively contributed $4.0 million to the Keep Wisconsin Warm Fund.

•We were required to implement escrow accounting treatment for pension and OPEB costs in 2023 and 2024.

•As discussed above, we were authorized to file a limited electric and natural gas rate case re-opener for 2024.

2022 Rates

In March 2021, we filed an application with the PSCW for the approval of certain accounting treatments that allowed us to maintain our electric, natural gas, and steam base rates through 2022 and forego filing a rate case for one year. In connection with the request, we also entered into an agreement, dated March 23, 2021, with various stakeholders. Pursuant to the terms of the agreement, the stakeholders fully supported the application. In September 2021, the PSCW issued a written order approving the application.

The final order reflected the following:

•We amortized, in 2022, certain previously deferred balances to offset approximately half of our forecasted revenue deficiency.

•We were able to defer any increases in tax expense due to changes in tax law that occurred in 2021 and/or 2022.

•We maintained our earnings sharing mechanism for 2022, with modification. The earnings sharing mechanism was modified to authorize us to retain 100.0% of the first 15 basis points of earnings above our then authorized ROE. The earnings sharing mechanism otherwise remained as previously authorized.

2023 Form 10-K 101 Wisconsin Electric Power Company

2020 and 2021 Rates

In March 2019, we filed an application with the PSCW to increase our retail electric, natural gas, and steam rates, effective January 1, 2020. In August 2019, we filed an application with the PSCW for approval of a settlement agreement entered into with certain intervenors to resolve several outstanding issues in our rate case. In December 2019, the PSCW issued a written order that approved the settlement agreement without material modification and addressed the remaining outstanding issues that were not included in the settlement agreement. The new rates were effective January 1, 2020. The final order reflected the following:

2020 Effective rate increase
Electric (1)	$	15.3	million	/	0.5%
Gas (2)	$	10.4	million	/	2.8%
Steam	$	1.9	million	/	8.6%
ROE	10.0%
Common equity component average on a financial basis	52.5%

(1)    Amount is net of certain deferred tax benefits from the Tax Legislation that were utilized to reduce near-term rate impacts. The rate order reflected the majority of the unprotected deferred tax benefits from the Tax Legislation being amortized evenly over two years, which resulted in approximately $65 million of tax benefits being amortized in each of 2020 and 2021. The unprotected deferred tax benefits related to the unrecovered balances of certain of our retired plants and our SSR regulatory asset were used to reduce the related regulatory asset. Unprotected deferred tax benefits by their nature are eligible to be returned to customers in a manner and timeline determined to be appropriate by the PSCW.

(2)    Amount includes certain deferred tax expense from the Tax Legislation. The rate order reflected all of the unprotected deferred tax expense from the Tax Legislation being amortized evenly over four years, which resulted in approximately $5 million of previously deferred tax expense being amortized each year. Unprotected deferred tax expense by its nature is eligible to be recovered from customers in a manner and timeline determined to be appropriate by the PSCW.

In accordance with our rate order, we filed an application with the PSCW in July 2020 requesting a financing order to securitize $100 million of Pleasant Prairie power plant's book value, plus the carrying costs accrued on the $100 million during the securitization process and the related financing fees. In November 2020, the PSCW issued a written order approving the application. The financing order also authorized us to form a bankruptcy-remote special purpose entity, WEPCo Environmental Trust, for the sole purpose of issuing ETBs to recover the approved costs. In May 2021, WEPCo Environmental Trust issued $118.8 million of 1.578% ETBs due December 15, 2035. See Note 21, Variable Interest Entities, for more information on WEPCo Environmental Trust.

The PSCW approved us continuing to have an earnings sharing mechanism through 2021. The earnings sharing mechanism was modified from its previous structure to one that was consistent with other Wisconsin investor-owned utilities. Under this earnings sharing mechanism, if we earned above our authorized ROE: (i) we retained 100.0% of earnings for the first 25 basis points above the authorized ROE; (ii) 50.0% of the next 50 basis points were required to be refunded to customers; and (iii) 100.0% of any remaining excess earnings were required to be refunded to customers. In addition, the rate order also required us to maintain residential and small commercial electric and natural gas customer fixed charges at previously authorized rates and to maintain the status quo for our electric market-based rate programs for large industrial customers through 2021.

Recovery of Natural Gas Costs

Due to the cold temperatures, wind, snow, and ice throughout the central part of the country during February 2021, the cost of gas purchased for our natural gas utility customers was temporarily driven significantly higher than our normal winter weather expectations. We have a regulatory mechanism in place for recovering all prudently incurred gas costs.

In March 2021, we received approval from the PSCW to recover approximately $54 million of natural gas costs in excess of the benchmark set in our GCRM over a period of three months, beginning in April 2021.

2023 Form 10-K 102 Wisconsin Electric Power Company

NOTE 25—OTHER INCOME, NET

Total other income, net was as follows for the years ended December 31:

(in millions)	2023		2022		2021
AFUDC-Equity	$	41.0	$	18.8	$	7.9
Non-service components of net periodic benefit costs	24.1		33.8		22.5
Other, net	3.7		(3.2)		1.7
Other income, net	$	68.8	$	49.4	$	32.1

NOTE 26—NEW ACCOUNTING PRONOUNCEMENTS

Improvements to Income Tax Disclosures

In December 2023, the FASB issued ASU No. 2023-09, Income Taxes (Topic 740): Improvements to Income Tax Disclosures. The amendments require additional disclosures, primarily related to income taxes paid and the rate reconciliation table. The amendments require disclosures on specific categories in the rate reconciliation table, as well as additional information for reconciling items that meet a quantitative threshold. For income taxes paid, additional disclosures are required to disaggregate federal, state, and foreign income taxes paid, with additional disclosures for income taxes paid that meet a quantitative threshold. The amendments are effective for annual periods beginning after December 15, 2024, with early adoption permitted. We plan to adopt these amendments beginning with our fiscal year ending on December 31, 2025, and are currently evaluating the impact this guidance may have on our financial statements and related disclosures.

Improvements to Reportable Segment Disclosures

In November 2023, the FASB issued ASU No. 2023-07, Segment Reporting (Topic 280): Improvements to Reportable Segment Disclosures. The amendments require additional disclosures about reportable segments on an annual and interim basis. The amendments require disclosure of significant segment expenses that are (1) regularly provided to the chief operating decision maker and (2) included in the reported measure of segment profit or loss. The amendments also require disclosure of an amount for other segment items and a description of its composition. The new standard also allows companies to disclose multiple measures of segment profit or loss if those measures are used to assess performance and allocate resources. The amendments are effective for fiscal years beginning after December 15, 2023, and interim periods within fiscal years beginning after December 15, 2024, with early adoption permitted. We plan to adopt these amendments beginning with our fiscal year ending on December 31, 2024, and are currently evaluating the impact this guidance may have on our financial statements and related disclosures.

Reference Rate Reform

In March 2020, the FASB issued ASU No. 2020-04, Reference Rate Reform (Topic 848): Facilitation of the Effects of Reference Rate Reform on Financial Reporting and in January 2021, the FASB issued ASU No. 2021-01, Reference Rate Reform (Topic 848): Scope. These pronouncements provide temporary optional expedients and exceptions for applying GAAP principles to contract modifications and hedging relationships to ease the financial reporting burdens of the market transition from LIBOR and other interbank offered rates to alternative reference rates. These pronouncements were effective upon issuance on March 12, 2020 through December 31, 2022. In December 2022, the FASB issued ASU No. 2022-06, Reference Rate Reform (Topic 848): Deferral of the Sunset Date of Topic 848, to extend the temporary accounting rules under Topic 848 from December 31, 2022 to December 31, 2024, after which entities will no longer be permitted to apply the relief in Topic 848. An entity may elect to apply the amendments prospectively from March 12, 2020 through December 31, 2024 by accounting topic. We do not anticipate this guidance having a significant impact on our financial statements and related disclosures.

2023 Form 10-K 103 Wisconsin Electric Power Company

ITEM 9. CHANGES IN AND DISAGREEMENTS WITH ACCOUNTANTS ON ACCOUNTING AND FINANCIAL DISCLOSURE

None.

ITEM 9A. CONTROLS AND PROCEDURES

Disclosure Controls and Procedures

Our management, with the participation of our principal executive officer and principal financial officer, has evaluated the effectiveness of our disclosure controls and procedures (as such term is defined in Rules 13a-15(e) and 15d-15(e) under the Exchange Act) as of the end of the period covered by this report. Based upon such evaluation, our principal executive officer and principal financial officer have concluded that, as of the end of such period, our disclosure controls and procedures are effective: (i) in recording, processing, summarizing and reporting, on a timely basis, information required to be disclosed by us in the reports that we file or submit under the Exchange Act; and (ii) to ensure that information required to be disclosed in the reports that we file or submit under the Exchange Act is accumulated and communicated to our management, including our principal executive officer and principal financial officer, to allow timely decisions regarding required disclosure.

Management's Report on Internal Control Over Financial Reporting

Our management is responsible for establishing and maintaining adequate internal control over financial reporting, as such term is defined in Exchange Act Rules 13a-15(f) and 15d-15(f). Under the supervision and with the participation of our management, including our principal executive officer and principal financial officer, we conducted an evaluation of the effectiveness of our internal control over financial reporting based on the framework in Internal Control – Integrated Framework (2013) issued by the Committee of Sponsoring Organizations of the Treadway Commission. Based on its evaluation, our management concluded that our internal control over financial reporting was effective as of December 31, 2023.

Because of its inherent limitations, internal control over financial reporting may not prevent or detect misstatements. Therefore, even those systems determined to be effective can provide only reasonable assurance with respect to financial statement preparation and presentation. Also, projections of any evaluation of the effectiveness of internal control over financial reporting to future periods are subject to the risk that the controls may become inadequate because of changes in conditions, or that the degree of compliance with the policies or procedures may deteriorate.

This Annual Report on Form 10-K does not include an attestation report of our independent registered public accounting firm regarding internal control over financial reporting. Management's report was not subject to attestation by our independent registered public accounting firm pursuant to rules of the SEC that permit us to provide only management's report in this annual report.

Changes in Internal Control Over Financial Reporting

There were no changes in our internal control over financial reporting (as such term is defined in Exchange Act Rules 13a-15(f) and 15d-15(f)) during the fourth quarter of 2023 that materially affected, or are reasonably likely to materially affect, our internal control over financial reporting.

ITEM 9B. OTHER INFORMATION

During the three months ended December 31, 2023, none of our directors or officers (as defined in Rule 16a-1 under the Exchange Act) adopted or terminated any contract, instruction, or written plan for the purchase or sale of our securities that was intended to satisfy the affirmative defense conditions of Rule 10b5-1(c) or any "non-Rule 10b5-1 trading arrangement" (as defined in Item 408 of Regulation S-K).

ITEM 9C. DISCLOSURE REGARDING FOREIGN JURISDICTIONS THAT PREVENT INSPECTIONS

Not applicable.

2023 Form 10-K 104 Wisconsin Electric Power Company

PART III

ITEM 10. DIRECTORS, EXECUTIVE OFFICERS AND CORPORATE GOVERNANCE OF THE REGISTRANT

The information under "Election of Directors," "Corporate Governance – Frequently Asked Questions," and "Committees of the WEC Energy Group Board of Directors" in our Definitive Information Statement on Schedule 14C to be filed with the SEC for our Annual Meeting of Shareholders to be held April 26, 2024 (the "2024 Annual Meeting Information Statement") is incorporated herein by reference. Also see "Information about our Executive Officers" in Part I of this report.

WEC Energy Group has adopted a written code of ethics, referred to as its Code of Business Conduct. We are a subsidiary of WEC Energy Group, and as such, all of our directors, executive officers, and employees, including our principal executive officer, principal financial officer and principal accounting officer, have a responsibility to comply with WEC Energy Group's Code of Business Conduct. WEC Energy Group has posted its Code of Business Conduct in the "Governance" section on its website, www.wecenergygroup.com. WEC Energy Group has not provided any waiver to the Code for any director, executive officer, or other employee. Any amendments to, or waivers for directors and executive officers from, the Code of Business Conduct will be disclosed on WEC Energy Group's website or in a current report on Form 8-K.

ITEM 11. EXECUTIVE COMPENSATION

The information under "Compensation Discussion and Analysis," "Executive Compensation," "Director Compensation," "Committees of the WEC Energy Group Board of Directors," "Pay Ratio Disclosure," "Risk Analysis of Compensation Policies and Practices," and "Certain Relationships and Related Transactions" in the 2024 Annual Meeting Information Statement is incorporated herein by reference.

ITEM 12. SECURITY OWNERSHIP OF CERTAIN BENEFICIAL OWNERS AND MANAGEMENT AND RELATED STOCKHOLDER MATTERS

All of our Common Stock is owned by our parent company, WEC Energy Group, Inc., 231 West Michigan Street, P.O. Box 1331, Milwaukee, Wisconsin 53201. Our directors and director nominees, who are all senior officers of WE and/or WEC Energy Group, as well as our other executive officers, do not own any of our voting securities. The information concerning their beneficial ownership in WEC Energy Group common stock set forth under "Owners of More Than 5% of Preferred Stock" and "Stock Ownership of Directors, Nominees and Executive Officers" in the 2024 Annual Meeting Information Statement is incorporated herein by reference.

We do not have any equity compensation plans under which our equity securities may be issued. Our directors, officers and certain employees participate in the compensation plans of WEC Energy Group.

ITEM 13. CERTAIN RELATIONSHIPS AND RELATED TRANSACTIONS, AND DIRECTOR INDEPENDENCE

The information under "Corporate Governance – Frequently Asked Questions" and "Certain Relationships and Related Transactions" in the 2024 Annual Meeting Information Statement is incorporated herein by reference. A full description of the guidelines the WEC Energy Group Board uses to determine director independence is located in Appendix A of WEC Energy Group's Corporate Governance Guidelines, which can be found on its website, www.wecenergygroup.com.

ITEM 14. PRINCIPAL ACCOUNTING FEES AND SERVICES

The information regarding the fees paid to, and services performed by, our independent auditors and the pre-approval policy of our audit and oversight committee under "Independent Auditors' Fees and Services" in the 2024 Annual Meeting Information Statement is incorporated herein by reference.

2023 Form 10-K 105 Wisconsin Electric Power Company

PART IV

ITEM 15. EXHIBITS AND FINANCIAL STATEMENT SCHEDULES

1.	Financial Statements and Report of Independent Registered Public Accounting Firm Included in Part II of This Report
	Description	Page in 10-K
	Report of Independent Registered Public Accounting Firm (PCAOB No. 34).	54
	Consolidated Income Statements for the three years ended December 31, 2023, 2022, and 2021.	56
	Consolidated Balance Sheets at December 31, 2023 and 2022.	57
	Consolidated Statements of Cash Flows for the three years ended December 31, 2023, 2022, and 2021.	58
	Consolidated Statements of Equity for the three years ended December 31, 2023, 2022, and 2021.	59
	Notes to Consolidated Financial Statements.	60
2.	Financial Statement Schedules Included in Part IV of This Report
	Schedule II, Valuation and Qualifying Accounts, for the three years ended December 31, 2023, 2022, and 2021.	110
	Other schedules are omitted because of the absence of conditions under which they are required or because the required information is given in the financial statements or notes thereto.
3.	Exhibits and Exhibit Index
	The following exhibits are filed or furnished with or incorporated by reference in the report with respect to Wisconsin Electric Power Company (File No. 001-01245). An asterisk (*) indicates that the exhibit has previously been filed with the SEC and is incorporated herein by reference. Each management contract and compensatory plan or arrangement required to be filed as an exhibit to this report pursuant to Item 15(b) of Form 10-K is identified below by two asterisks (**) following the description of the exhibit.

Number	Exhibit
3	Articles of Incorporation and By-laws
	3.1*	Restated Articles of Incorporation of WE, as amended and restated effective January 10, 1995. (Exhibit (3)-1 to WE's 12/31/94 Form 10-K.)
	3.2*	Bylaws of WE, as amended to May 1, 2000. (Exhibit (3)-2 to WE's 03/31/00 Form 10-Q.)
4	Instruments defining the rights of security holders, including indentures
	4.1*	Reference is made to Article III of the Restated Articles of Incorporation of WE. (See Exhibit 3.1 above.)
	4.2*	Description of WE's Preferred Stock. (Exhibit 4.2 to WE's 12/31/19 Form 10-K.)
	Indentures and Securities Resolutions:
	4.3*	Indenture for Debt Securities of WE (the "WE Indenture"), dated December 1, 1995. (Exhibit (4)-1 to WE's 12/31/95 Form 10-K.)
	4.4*	Securities Resolution No. 1 of WE under the WE Indenture, dated December 5, 1995. (Exhibit (4)-2 to WE's 12/31/95 Form 10-K.)

2023 Form 10-K 106 Wisconsin Electric Power Company

Number	Exhibit
	4.5*	Securities Resolution No. 3 of WE under the WE Indenture, dated May 27, 1998. (Exhibit (4)-1 to WE's 06/30/98 Form 10-Q.)
	4.6*	Securities Resolution No. 5 of WE under the WE Indenture, dated as of May 1, 2003. (Exhibit 4.47 filed with Post-Effective Amendment No. 1 to WE's Registration Statement on Form S-3 (File No. 333-101054), filed May 6, 2003.)
	4.7*	Securities Resolution No. 7 of WE under the WE Indenture, dated as of November 2, 2006. (Exhibit 4.1 to WE's 11/02/06 Form 8-K.)
	4.8*	Securities Resolution No. 12 of WE under the WE Indenture, dated as of December 5, 2012. (Exhibit 4.1 to WE's 12/05/12 Form 8-K.)
	4.9*	Securities Resolution No. 14 of WE under the WE Indenture, dated as of May 12, 2014. (Exhibit 4.1 to WE's 05/12/14 Form 8-K.)
	4.10*	Securities Resolution No. 15 of WE under the WE Indenture, dated as of May 14, 2015. (Exhibit 4.1 to WE's 05/14/15 Form 8-K.)
	4.11*	Securities Resolution No. 16 of WE under the WE Indenture, dated as of November 13, 2015. (Exhibit 4.1 to WE's 11/13/15 Form 8-K.)
	4.12*	Securities Resolution No. 17 of WE under the WE Indenture, dated as of October 1, 2018. (Exhibit 4.1 to WE's 10/01/18 Form 8-K.)
	4.13*	Securities Resolution No. 18 of WE under the WE Indenture, dated as of December 3, 2019. (Exhibit 4.1 to WE's 12/03/2019 Form 8-K.)
	4.14*	Securities Resolution No. 19 of WE under the WE Indenture, dated as of June 8, 2021. (Exhibit 4.1 to WE's 06/15/21 Form 8-K.)
	4.15*	Securities Resolution No. 20 of WE under the WE Indenture, dated as of September 14, 2022. (Exhibit 4.1 to WE's 09/22/22 Form 8-K.)
		The forgoing list of exhibits does not include certain unregistered long-term debt instruments of the Registrant and its subsidiary where the total amount of securities authorized to be issued under the instrument does not exceed 10 percent of the total assets of the Registrant and its subsidiary on a consolidated basis. The Registrant agrees pursuant to Item 601(b)(4) of Regulation S-K to furnish to the Securities and Exchange Commission, upon request, a copy of all such agreements and instruments.
10	Material Contracts
	10.1*	WEC Energy Group Supplemental Pension Plan, Amended and Restated Effective as of January 1, 2018. (Exhibit 10.1 to WEC Energy Group's 12/31/18 Form 10-K (File No. 001-09057).)**
	10.2*	Legacy Wisconsin Energy Corporation Executive Deferred Compensation Plan, Amended and Restated as of January 1, 2018. (Exhibit 10.2 to WEC Energy Group's 12/31/18 Form 10-K (File No. 001-09057).)**
	10.3*	WEC Energy Group Executive Deferred Compensation Plan, Amended and Restated Effective as of January 1, 2018. (Exhibit 10.3 to WEC Energy Group's 12/31/18 Form 10-K (File No. 001-09057).)**
	10.4	Amendment dated as of December 20, 2023 to the WEC Energy Group Executive Deferred Compensation Plan, Amended and Restated Effective as of January 1, 2018.**
	10.5*	WEC Energy Group Non-Qualified Retirement Savings Plan, Amended and Restated Effective as of January 1, 2018. (Exhibit 10.6 to WEC Energy Group's 12/31/18 Form 10-K (File No. 001-09057).)**
	10.6*	WEC Energy Group Supplemental Long Term Disability Plan, Amended and Restated Effective as of January 1, 2017. (Exhibit 10.7 to WEC Energy Group's 12/31/18 Form 10-K (File No. 001-09057).)**

2023 Form 10-K 107 Wisconsin Electric Power Company

Number	Exhibit
	10.7*	WEC Energy Group Short-Term Performance Plan, Amended and Restated Effective as of January 1, 2019. (Exhibit 10.8 to WEC Energy Group's 12/31/18 Form 10-K (File No. 001-09057).)**
	10.8*	Wisconsin Energy Corporation 2014 Rabbi Trust Agreement by and between Wisconsin Energy Corporation and The Northern Trust Company dated February 23, 2015, regarding the trust established to provide a source of funds to assist in meeting the liabilities under various nonqualified deferred compensation plans made between Wisconsin Energy Corporation or its subsidiaries and various plan participants. (Exhibit 10.13 to Wisconsin Energy Corporation's 12/31/14 Form 10-K (File No. 001-09057).)**
	10.9*	Retention Agreement by and between WEC Energy Group and Scott J. Lauber, dated February 21, 2022. (Exhibit 10.16 to WEC Energy Group's 12/31/21 Form 10-K. (File No. 001-09057).)**
	10.10*	Letter Agreement by and between WEC Energy Group, Inc. and Xia Liu, dated March 24, 2020. (Exhibit 10.2 to WEC Energy Group's 03/31/20 Form 8-K (File No. 001-09057).)**
	10.11*	Letter Agreement by and between Wisconsin Energy Corporation and Robert Garvin, dated January 31, 2011. (Exhibit 10.1 to Wisconsin Energy Corporation's 03/31/11 Form 10-Q (File No. 001-09057).)**
	10.12*	Letter Agreement by and between WEC Energy Group, Inc. and Margaret C. Kelsey, dated as of July 19, 2017. (Exhibit 10.1 to WEC Energy Group's 09/30/17 Form 10-Q. (File No. 001-09057).)**
	10.13.1*	WEC Energy Group Omnibus Stock Incentive Plan, Amended and Restated Effective as of January 1, 2016. (Exhibit 10.19 to WEC Energy Group's 12/31/15 Form 10-K (File No. 001-09057).)**
	10.13.2*	WEC Energy Group Omnibus Stock Incentive Plan, amended and restated effective as of May 6, 2021. (Exhibit 10.1 to WEC Energy Group's 05/11/21 Form 8-K (File No. 001-09057).)**
	10.14*	WEC Energy Group Performance Unit Plan, amended and restated effective as of January 1, 2017. (Exhibit 10.1 to WEC Energy Group's 12/01/16 Form 8-K (File No. 001-09057).)**
	10.15*	WEC Energy Group Performance Unit Plan, amended and restated effective as of January 1, 2023. (Exhibit 10.1 to WEC Energy Group's 12/02/22 Form 8-K (File No. 001-09057).)**
	10.16*	Wisconsin Energy Corporation Terms and Conditions Governing Non-Qualified Stock Option Award for option awards under the WEC Energy Group Omnibus Stock Incentive Plan, approved December 4, 2014. (Exhibit 10.3 to Wisconsin Energy Corporation's 12/04/14 Form 8-K (File No. 001-09057).)**
	10.17*	2016 WEC Energy Group Terms and Conditions Governing Non-Qualified Stock Option Award for option awards under the WEC Energy Group Omnibus Stock Incentive Plan. (Exhibit 10.29 to WEC Energy Group’s 12/31/15 Form 10-K (File No. 001-09057).)**
	10.18*	Non-Qualified Stock Option Award Terms and Conditions under the WEC Energy Group Omnibus Stock Incentive Plan. (Exhibit 10.2 to WEC Energy Group's 06/30/21 Form 10-Q (File No. 001-09057).)**
	10.19*	Restricted Stock Award Terms and Conditions under the WEC Energy Group Omnibus Stock Incentive Plan. (Exhibit 10.3 to WEC Energy Group's 06/30/21 Form 10-Q (File No. 001-09057).)**
	10.20*	Port Washington I Facility Lease Agreement between Port Washington Generating Station LLC, as Lessor, and Wisconsin Electric Power Company, as Lessee, dated as of May 28, 2003. (Exhibit 10.7 to WE's 06/30/03 Form 10-Q.)
	10.21*	Port Washington II Facility Lease Agreement between Port Washington Generating Station LLC, as Lessor, and Wisconsin Electric Power Company, as Lessee, dated as of May 28, 2003. (Exhibit 10.8 to WE's 06/30/03 Form 10-Q.)
	10.22*	Elm Road I Facility Lease Agreement between Elm Road Generating Station Supercritical, LLC, as Lessor, and Wisconsin Electric Power Company, as Lessee, dated as of November 9, 2004. (Exhibit 10.56 to Wisconsin Energy Corporation's 12/31/04 Form 10-K (File No. 001-09057).)
	10.23*	Elm Road II Facility Lease Agreement between Elm Road Generating Station Supercritical, LLC, as Lessor, and Wisconsin Electric Power Company, as Lessee, dated as of November 9, 2004. (Exhibit 10.57 to Wisconsin Energy Corporation's 12/31/04 Form 10-K (File No. 001-09057).)

2023 Form 10-K 108 Wisconsin Electric Power Company

Number	Exhibit
	10.24*	Point Beach Nuclear Plant Power Purchase Agreement between FPL Energy Point Beach, LLC and Wisconsin Electric Power Company, dated as of December 19, 2006 (the "PPA"). (Exhibit 10.1 to Wisconsin Energy Corporation's 03/31/08 Form 10-Q (File No. 001-09057).)
	10.25*	Letter Agreement between Wisconsin Electric Power Company and FPL Energy Point Beach, LLC, dated October 31, 2007, which amends the PPA. (Exhibit 10.45 to Wisconsin Energy Corporation's 12/31/07 Form 10-K (File No. 001-09057).)
23	Consents of Experts and Counsel
	23.1	Deloitte & Touche LLP – Milwaukee, WI, Consent of Independent Registered Public Accounting Firm for WE.
31	Rule 13a-14(a)/15d-14(a) Certifications
	31.1	Certification Pursuant to Rule 13a-14(a) or 15d-14(a), as Adopted Pursuant to Section 302 of the Sarbanes-Oxley Act of 2002.
	31.2	Certification Pursuant to Rule 13a-14(a) or 15d-14(a), as Adopted Pursuant to Section 302 of the Sarbanes-Oxley Act of 2002.
32	Section 1350 Certifications
	32.1	Certification Pursuant to 18 U.S.C. Section 1350, as Adopted Pursuant to Section 906 of the Sarbanes-Oxley Act of 2002.
	32.2	Certification Pursuant to 18 U.S.C. Section 1350, as Adopted Pursuant to Section 906 of the Sarbanes-Oxley Act of 2002.
101	Interactive Data File
	101.INS	Inline XBRL Instance Document – the instance document does not appear in the Interactive Data File because its XBRL tags are embedded within the Inline XBRL document
	101.SCH	Inline XBRL Taxonomy Extension Schema
	101.CAL	Inline XBRL Taxonomy Extension Calculation Linkbase
	101.DEF	Inline XBRL Taxonomy Extension Definition Linkbase
	101.LAB	Inline XBRL Taxonomy Extension Label Linkbase
	101.PRE	Inline XBRL Taxonomy Extension Presentation Linkbase
104	Cover Page Interactive Data File (formatted as Inline XBRL and contained in Exhibit 101)

ITEM 16. FORM 10-K SUMMARY

None.

2023 Form 10-K 109 Wisconsin Electric Power Company

SCHEDULE II

WISCONSIN ELECTRIC POWER COMPANY

VALUATION AND QUALIFYING ACCOUNTS

Allowance for Doubtful Accounts (in millions)	Balance at Beginning of Period		Expense (1)		Deferral		Net Write-offs (2)		Balance at End of Period
December 31, 2023	$	49.7	$	23.8	$	45.7	$	(74.7)	$	44.5
December 31, 2022	51.4		27.3		34.0		(63.0)		49.7
December 31, 2021	59.3		24.8		(0.3)		(32.4)		51.4

(1)    Net of recoveries.

(2)    Represents amounts written off to the reserve, net of adjustments to regulatory assets.

2023 Form 10-K 110 Wisconsin Electric Power Company

SIGNATURES

Pursuant to the requirements of Section 13 or 15(d) of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned, thereunto duly authorized.

		WISCONSIN ELECTRIC POWER COMPANY
	By	/s/ SCOTT J. LAUBER
Date:	February 22, 2024	Scott J. Lauber
		Chairman of the Board, President and Chief Executive Officer

Pursuant to the requirements of the Securities Exchange Act of 1934, this report has been signed below by the following persons on behalf of the registrant and in the capacities and on the dates indicated.

/s/ SCOTT J. LAUBER	February 22, 2024
Scott J. Lauber, Chairman of the Board, President, Chief Executive Officer and
Director -- Principal Executive Officer
/s/ XIA LIU	February 22, 2024
Xia Liu, Executive Vice President, Chief Financial
Officer and Director -- Principal Financial Officer
/s/ WILLIAM J. GUC	February 22, 2024
William J. Guc, Vice President, Controller, and Assistant
Corporate Secretary -- Principal Accounting Officer
/s/ MARGARET C. KELSEY	February 22, 2024
Margaret C. Kelsey, Director
/s/ GALE E. KLAPPA	February 22, 2024
Gale E. Klappa, Director
/s/ WILLIAM MASTORIS	February 22, 2024
William Mastoris, Director
/s/ PAUL J. SPICER	February 22, 2024
Paul J. Spicer, Director

2023 Form 10-K 111 Wisconsin Electric Power Company

EX-10.4

Exhibit 10.4

AMENDMENT TO THE

WEC ENERGY GROUP

EXECUTIVE DEFERRED COMPENSATION PLAN

WHEREAS, WEC Energy Group, Inc. (the "Company") has established and maintains the WEC Energy Group Executive Deferred Compensation Plan, as restated effective January 1, 2018 (the "Plan");

WHEREAS, Section 8.2 of the Plan reserves to the Company's Board of Directors, its Compensation Committee or an internal administrative committee appointed by the Chief Executive Officer of the Company the authority to amend the Plan; provided such amendments do not decrease the amount of any participant's account as of the date of the amendment;

WHEREAS, the Chief Executive Officer of the Company has appointed the Non‑qualified Benefit Plans Committee (the "Committee") as the administrator of the Plan;

WHEREAS, prior to 2019, the Internal Revenue Code (the "Code") required that individuals who elected a hardship withdrawal from a 401(k) plan be prohibited from making salary deferrals for six months thereafter;

WHEREAS, pursuant to legislative changes, in 2019 and 2020, 401(k) plan sponsors had the option to remove the salary deferral suspension requirement for an individual who elected a hardship withdrawal, and, beginning in 2021, 401(k) plan sponsors were required to remove the salary deferral suspension provision;

WHEREAS, Section 2.5(c) of the Plan includes a provision that mirrors the pre-2019 401(k) plan deferral suspension language, as applied to deferrals made to the Plan;

WHEREAS, the purpose for the Plan to include mirror deferral suspension language no longer exists, with the removal of that language from the Company’s 401(k) plans;

WHEREAS, the Company desires to amend the Plan to delete Section 2.5(c) of the Plan;

WHEREAS, the above changes are not intended to be material modifications for purposes of Internal Revenue Code section 162(m) as described in Internal Revenue Service Notice 2018‑68; and

WHEREAS, the Committee has determined that the amendments are within the scope of its authority.

NOW, THEREFORE, BE IT RESOLVED, that the Company hereby amends Plan Section 2.5 to delete subsection (c) and to re-letter subsection (d) accordingly, effective as of January 1, 2024, with the amended Section 2.5 to read as follows:

2.5 Cessation of Participation.

(a)    The Committee shall have the sole discretionary authority to exclude a Participant from making further deferrals under the Plan with such exclusion becoming effective as of the first day of the immediately following Plan Year. Such Participant shall remain a Participant in the Plan until the Participant's Account balance is paid in full.

(b)    Elective deferrals made by a Participant or Beneficiary who receives a distribution due to an Unforeseeable Emergency pursuant to section 5.8 shall be cancelled due to such distribution if the Committee so decides in its discretion. In either event, the Participant (or Beneficiary, as applicable) shall remain a Participant in the Plan until the Participant's Account balance is paid in full.

(c)    Notwithstanding anything in the Plan to the contrary, upon the earlier to occur of a Participant's Separation from Service or death, any outstanding deferral election shall be given effect to the extent any amounts covered by such election are paid after such event. Payment of deferred amounts shall be made pursuant to Article 5.

FURTHER RESOLVED, that the Committee is authorized and directed, in the name of and for the Company, to take any and all actions as deemed necessary or appropriate to effect the intent of the foregoing Resolutions including, but not limited to, the execution of this amendment, with such changes as in the opinion of the Committee may be necessary and appropriate. Such opinion shall be conclusively evidenced by the Committee's execution of the amendment.

Dated this 20th day of December, 2023.

WEC ENERGY GROUP, INC.

NON-QUALIFIED BENEFIT PLANS COMMITTEE

/s/ Lisa R. George

Lisa R. George

/s/ David L. Hughes

David L. Hughes

/s/Greta G. Weathersby

Greta G. Weathersby

EX-23.1

Exhibit 23.1

CONSENT OF INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM

We consent to the incorporation by reference in Registration Statement No. 333-254615 on Form S-3 of our report dated February 22, 2024, relating to the consolidated financial statements and financial statement schedule of Wisconsin Electric Power Company appearing in this Annual Report on Form 10-K of Wisconsin Electric Power Company for the year ended December 31, 2023.

/s/ DELOITTE & TOUCHE LLP

Milwaukee, Wisconsin

February 22, 2024

EX-31.1

Certification Pursuant to                 Exhibit 31.1

Rule 13a-14(a) or 15d-14(a),

as Adopted Pursuant to

Section 302 of the Sarbanes-Oxley Act of 2002

I, Scott J. Lauber, certify that:

1.I have reviewed this Annual Report on Form 10-K of Wisconsin Electric Power Company;

2.Based on my knowledge, this report does not contain any untrue statement of a material fact or omit to state a material fact necessary to make the statements made, in light of the circumstances under which such statements were made, not misleading with respect to the period covered by this report;

3.Based on my knowledge, the financial statements, and other financial information included in this report, fairly present in all material respects the financial condition, results of operations and cash flows of the registrant as of, and for, the periods presented in this report;

4.The registrant's other certifying officer(s) and I are responsible for establishing and maintaining disclosure controls and procedures (as defined in Exchange Act Rules 13a-15(e) and 15d-15(e)) and internal control over financial reporting (as defined in Exchange Act Rules 13a-15(f) and 15d-15(f)) for the registrant and have:

a)Designed such disclosure controls and procedures, or caused such disclosure controls and procedures to be designed under our supervision, to ensure that material information relating to the registrant, including its consolidated subsidiaries, is made known to us by others within those entities, particularly during the period in which this report is being prepared;

b)Designed such internal control over financial reporting, or caused such internal control over financial reporting to be designed under our supervision, to provide reasonable assurance regarding the reliability of financial reporting and the preparation of financial statements for external purposes in accordance with generally accepted accounting principles;

c)Evaluated the effectiveness of the registrant's disclosure controls and procedures and presented in this report our conclusions about the effectiveness of the disclosure controls and procedures, as of the end of the period covered by this report based on such evaluation; and

d)Disclosed in this report any change in the registrant's internal control over financial reporting that occurred during the registrant's most recent fiscal quarter (the registrant's fourth fiscal quarter in the case of an Annual Report) that has materially affected, or is reasonably likely to materially affect, the registrant's internal control over financial reporting; and

5.The registrant's other certifying officer(s) and I have disclosed, based on our most recent evaluation of internal control over financial reporting, to the registrant's auditors and the audit committee of the registrant's board of directors (or persons performing the equivalent functions):

a)All significant deficiencies and material weaknesses in the design or operation of internal control over financial reporting which are reasonably likely to adversely affect the registrant's ability to record, process, summarize and report financial information; and

b)Any fraud, whether or not material, that involves management or other employees who have a significant role in the registrant's internal control over financial reporting.

Date: February 22, 2024

/s/ SCOTT J. LAUBER

Scott J. Lauber
Chairman of the Board, President and Chief Executive Officer
(Principal Executive Officer)

EX-31.2

Certification Pursuant to                 Exhibit 31.2

Rule 13a-14(a) or 15d-14(a),

as Adopted Pursuant to

Section 302 of the Sarbanes-Oxley Act of 2002

I, Xia Liu, certify that:

1.I have reviewed this Annual Report on Form 10-K of Wisconsin Electric Power Company;

2.Based on my knowledge, this report does not contain any untrue statement of a material fact or omit to state a material fact necessary to make the statements made, in light of the circumstances under which such statements were made, not misleading with respect to the period covered by this report;

3.Based on my knowledge, the financial statements, and other financial information included in this report, fairly present in all material respects the financial condition, results of operations and cash flows of the registrant as of, and for, the periods presented in this report;

4.The registrant's other certifying officer(s) and I are responsible for establishing and maintaining disclosure controls and procedures (as defined in Exchange Act Rules 13a-15(e) and 15d-15(e)) and internal control over financial reporting (as defined in Exchange Act Rules 13a-15(f) and 15d-15(f)) for the registrant and have:

a)Designed such disclosure controls and procedures, or caused such disclosure controls and procedures to be designed under our supervision, to ensure that material information relating to the registrant, including its consolidated subsidiaries, is made known to us by others within those entities, particularly during the period in which this report is being prepared;

b)Designed such internal control over financial reporting, or caused such internal control over financial reporting to be designed under our supervision, to provide reasonable assurance regarding the reliability of financial reporting and the preparation of financial statements for external purposes in accordance with generally accepted accounting principles;

c)Evaluated the effectiveness of the registrant's disclosure controls and procedures and presented in this report our conclusions about the effectiveness of the disclosure controls and procedures, as of the end of the period covered by this report based on such evaluation; and

d)Disclosed in this report any change in the registrant's internal control over financial reporting that occurred during the registrant's most recent fiscal quarter (the registrant's fourth fiscal quarter in the case of an Annual Report) that has materially affected, or is reasonably likely to materially affect, the registrant's internal control over financial reporting; and

5.The registrant's other certifying officer(s) and I have disclosed, based on our most recent evaluation of internal control over financial reporting, to the registrant's auditors and the audit committee of the registrant's board of directors (or persons performing the equivalent functions):

a)All significant deficiencies and material weaknesses in the design or operation of internal control over financial reporting which are reasonably likely to adversely affect the registrant's ability to record, process, summarize and report financial information; and

b)Any fraud, whether or not material, that involves management or other employees who have a significant role in the registrant's internal control over financial reporting.

Date: February 22, 2024

/s/ XIA LIU

Xia Liu
Executive Vice President and Chief Financial Officer
(Principal Financial Officer)

EX-32.1

Exhibit 32.1

Certification Pursuant to

18 U.S.C. Section 1350,

As Adopted Pursuant to

Section 906 of the Sarbanes-Oxley Act of 2002

In connection with the Annual Report of Wisconsin Electric Power Company (the "Company") on Form 10-K for the period ended December 31, 2023, as filed with the Securities and Exchange Commission on February 22, 2024 (the "Report"), I, Scott J. Lauber, Chairman of the Board, President and Chief Executive Officer of the Company, hereby certify, pursuant to 18 U.S.C. Section 1350, as adopted pursuant to Section 906 of the Sarbanes-Oxley Act of 2002, to the best of my knowledge, that:

(1)The Report fully complies with the requirements of section 13(a) or 15(d) of the Securities Exchange Act of 1934; and

(2)The information contained in the Report fairly presents, in all material respects, the financial condition and results of operations of the Company.

/s/ SCOTT J. LAUBER

Scott J. Lauber
Chairman of the Board, President and Chief Executive Officer

February 22, 2024

EX-32.2

Exhibit 32.2

Certification Pursuant to

18 U.S.C. Section 1350,

As Adopted Pursuant to

Section 906 of the Sarbanes-Oxley Act of 2002

In connection with the Annual Report of Wisconsin Electric Power Company (the "Company") on Form 10-K for the period ended December 31, 2023, as filed with the Securities and Exchange Commission on February 22, 2024 (the "Report"), I, Xia Liu, Executive Vice President and Chief Financial Officer of the Company, hereby certify, pursuant to 18 U.S.C. Section 1350, as adopted pursuant to Section 906 of the Sarbanes-Oxley Act of 2002, to the best of my knowledge, that:

(1)The Report fully complies with the requirements of section 13(a) or 15(d) of the Securities Exchange Act of 1934; and

(2)The information contained in the Report fairly presents, in all material respects, the financial condition and results of operations of the Company.

/s/ XIA LIU

Xia Liu
Executive Vice President and Chief Financial Officer

February 22, 2024

XML

Cover Page - USD ($)
$ in Millions

12 Months Ended

Dec. 31, 2023

Jan. 31, 2024

Jun. 30, 2023

Entity Information [Line Items]

Document Type

10-K

Document Annual Report

true

Document Period End Date

Dec. 31, 2023

Document Transition Report

false

Entity File Number

001-01245

Entity Registrant Name

WISCONSIN ELECTRIC POWER COMPANY

Entity Tax Identification Number

39-0476280

Entity Incorporation, State or Country Code

WI

Entity Address, Address Line One

231 West Michigan Street

Entity Address, Address Line Two

P.O. Box 2046

Entity Address, City or Town

Milwaukee

Entity Address, State or Province

WI

Entity Address, Postal Zip Code

53201

City Area Code

414

Local Phone Number

221-2345

Entity Well-known Seasoned Issuer

No

Entity Voluntary Filers

No

Entity Current Reporting Status

Yes

Entity Interactive Data Current

Yes

Entity Filer Category

Non-accelerated Filer

Entity Small Business

false

Entity Emerging Growth Company

false

ICFR Auditor Attestation Flag

false

Document Financial Statement Error Correction

false

Entity Shell Company

false

Entity Public Float

$ 0.0

Entity Common Stock, Shares Outstanding

33,289,327

Documents Incorporated by Reference

Portions of Wisconsin Electric Power Company's Definitive Information Statement on Schedule 14C for its Annual Meeting of Shareholders, to be held on April 26, 2024, are incorporated by reference into Part III hereof.

Entity Central Index Key

0000107815

Current Fiscal Year End Date

--12-31

Document Fiscal Year Focus

2023

Document Fiscal Period Focus

FY

Amendment Flag

false

Serial preferred stock, 3.60% Series

Entity Information [Line Items]

Title of 12(g) Security

Serial Preferred Stock, 3.60% Series, $100 Par Value

No Trading Symbol Flag

true

Six Per Cent. Preferred Stock

Entity Information [Line Items]

Title of 12(g) Security

Six Per Cent. Preferred Stock, $100 Par Value

No Trading Symbol Flag

true

XML

Audit Information	12 Months Ended
	Dec. 31, 2023
Audit Information [Abstract]
Auditor Name	DELOITTE & TOUCHE LLP
Auditor Location	Milwaukee, Wisconsin
Auditor Firm ID	34

XML

Consolidated Income Statements - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Income Statement [Abstract]
Operating revenues	$ 4,045.0	$ 4,070.3	$ 3,664.5
Operating expenses
Cost of sales	1,451.4	1,693.3	1,341.1
Other operation and maintenance	931.1	831.7	898.4
Depreciation and amortization	525.0	479.7	457.9
Property and revenue taxes	115.3	125.6	98.4
Total operating expenses	3,022.8	3,130.3	2,795.8
Operating income	1,022.2	940.0	868.7
Other income, net	68.8	49.4	32.1
Interest expense	466.5	458.4	460.3
Other expense	(397.7)	(409.0)	(428.2)
Income before income taxes	624.5	531.0	440.5
Income tax expense	142.7	133.1	58.1
Net income	481.8	397.9	382.4
Preferred stock dividend requirements	1.2	1.2	1.2
Net income attributed to common shareholder	$ 480.6	$ 396.7	$ 381.2

XML

Consolidated Balance Sheets - USD ($) $ in Millions	Dec. 31, 2023	Dec. 31, 2022
Current Assets
Cash and cash equivalents	$ 6.1	$ 6.1
Materials, supplies, and inventories	310.6	292.9
Prepaid taxes	112.7	113.1
Other prepayments	26.7	25.6
Other	32.3	73.8
Current assets	1,205.3	1,207.3
Long-term assets
Property, plant, and equipment, net of accumulated depreciation and amortization of $5,779.2 and $5,450.3, respectively	11,585.5	10,718.6
Regulatory assets (December 31, 2023 and December 31, 2022 include $85.9 and $92.4, respectively, related to WEPCo Environmental Trust)	2,860.7	2,817.5
Pension and OPEB assets	71.0	143.3
Other	118.9	133.5
Long-term assets	14,636.1	13,812.9
Total assets	15,841.4	15,020.2
Current Liabilities
Short-term debt	360.8	460.7
Current portion of long-term debt (December 31, 2023 and December 31, 2022 include $9.0 and $8.9, respectively, related to WEPCo Environmental Trust)	309.0	8.9
Current portion of finance lease obligations	87.8	112.3
Other	201.4	210.5
Current liabilities	1,484.9	1,372.3
Long-term liabilities
Long-term debt (December 31, 2023 and December 31, 2022 include $85.3 and $94.1, respectively, related to WEPCo Environmental Trust)	3,045.4	3,351.5
Finance lease obligations	2,752.2	2,702.3
Deferred income taxes	1,513.5	1,467.3
Regulatory liabilities	1,631.4	1,637.4
Other	330.5	322.2
Long-term liabilities	9,273.0	9,480.7
Commitments and contingencies (Note 22)
Common shareholder's equity
Common stock – $10 par value; 65,000,000 shares authorized; 33,289,327 shares outstanding	332.9	332.9
Additional paid in capital	2,552.4	1,746.8
Retained earnings	2,167.8	2,057.1
Common shareholder's equity	5,053.1	4,136.8
Preferred stock	30.4	30.4
Total liabilities and equity	15,841.4	15,020.2
Nonrelated Party
Current Assets
Accounts receivable	573.0	582.6
Current Liabilities
Accounts Payable, Current	332.1	400.5
Related Party
Current Assets
Accounts receivable	143.9	113.2
Current Liabilities
Accounts Payable, Current	$ 193.8	$ 179.4

XML

Consolidated Balance Sheets Parenthetical (Parentheticals) - USD ($) $ in Millions	Dec. 31, 2023	Dec. 31, 2022
Statement of Financial Position [Abstract]
Accounts receivable and unbilled revenues, reserves	$ 44.5	$ 49.7
Property, plant, and equipment, accumulated depreciation and amortization	$ 5,779.2	$ 5,450.3
Common stock, par value	$ 10	$ 10
Common stock, shares authorized	65,000,000	65,000,000
Common stock, shares outstanding	33,289,327	33,289,327
Regulatory assets (December 31, 2023 and December 31, 2022 include $85.9 and $92.4, respectively, related to WEPCo Environmental Trust)	$ 2,860.7	$ 2,817.5
Current portion of long-term debt (December 31, 2023 and December 31, 2022 include $9.0 and $8.9, respectively, related to WEPCo Environmental Trust)	309.0	8.9
Long-term debt (December 31, 2023 and December 31, 2022 include $85.3 and $94.1, respectively, related to WEPCo Environmental Trust)	3,045.4	3,351.5
WEPCo Environmental Trust
Regulatory assets (December 31, 2023 and December 31, 2022 include $85.9 and $92.4, respectively, related to WEPCo Environmental Trust)	85.9	92.4
Current portion of long-term debt (December 31, 2023 and December 31, 2022 include $9.0 and $8.9, respectively, related to WEPCo Environmental Trust)	9.0	8.9
Long-term debt (December 31, 2023 and December 31, 2022 include $85.3 and $94.1, respectively, related to WEPCo Environmental Trust)	$ 85.3	$ 94.1

XML

Consolidated Statements of Cash Flows - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Statement of Cash Flows [Abstract]
Net income	$ 481.8	$ 397.9	$ 382.4
Reconciliation to cash provided by operating activities
Depreciation and amortization	525.0	479.7	457.9
Deferred income taxes and ITCs, net	20.7	54.6	(26.4)
Net change in transmission regulatory asset and liability	18.4	(64.2)	2.7
Change In
Accounts receivable and unbilled revenues, net	(4.6)	(69.8)	(68.4)
Materials, supplies, and inventories	(12.8)	(46.5)	(26.9)
Collateral on deposit	20.0	(40.9)	0.8
Other current assets	(4.8)	(16.1)	(0.9)
Accounts payable	(41.3)	14.5	85.5
Other current liabilities	(8.2)	28.8	(6.9)
Other, net	(55.1)	(101.0)	2.4
Net cash provided by operating activities	939.1	637.0	802.2
Investing Activities
Capital expenditures	(1,094.6)	(930.4)	(813.3)
Acquisition of Whitewater	(38.0)	0.0	0.0
Acquisition of West Riverside	(95.3)	0.0	0.0
Proceeds from the sale of assets	24.3	1.6	1.4
Payments for ATC's construction costs that will be reimbursed	(16.5)	(19.2)	(2.6)
Proceeds from assets transferred to affiliates	0.0	0.0	10.7
Insurance proceeds received for property damage	0.5	41.0	0.0
Other, net	(7.7)	(7.0)	5.8
Net cash used in investing activities	(1,227.3)	(914.0)	(798.0)
Financing Activities
Change in short-term debt	(99.9)	85.7	83.0
Issuance of long-term debt	0.0	500.0	418.8
Retirement of long-term debt	(8.9)	(8.8)	(304.1)
Payments for finance lease obligations	(77.0)	(73.6)	(67.5)
Equity contribution from parent	805.0	455.0	230.0
Payment of dividends to parent	(370.0)	(630.0)	(360.0)
Other, net	(1.2)	(6.6)	(8.6)
Net cash provided by (used in) financing activities	248.0	321.7	(8.4)
Net change in cash, cash equivalents, and restricted cash	(40.2)	44.7	(4.2)
Cash, cash equivalents, and restricted cash at beginning of year	47.7	3.0	7.2
Cash, cash equivalents, and restricted cash at end of year	$ 7.5	$ 47.7	$ 3.0

XML

Consolidated Statements of Equity - USD ($) $ in Millions	Total	Total common shareholder's equity	Common stock	Additional paid-in capital	Retained earnings	Preferred stock
Balance at Dec. 31, 2020	$ 3,692.6	$ 3,662.2	$ 332.9	$ 1,060.1	$ 2,269.2	$ 30.4
Equity
Net income attributed to common shareholder	381.2	381.2	0.0	0.0	381.2	0.0
Payment of dividends to parent	(360.0)	(360.0)	0.0	0.0	(360.0)	0.0
Equity contribution from parent	230.0	230.0	0.0	230.0	0.0	0.0
Stock-based compensation and other	0.9	0.9	0.0	0.8	0.1	0.0
Balance at Dec. 31, 2021	3,944.7	3,914.3	332.9	1,290.9	2,290.5	30.4
Equity
Net income attributed to common shareholder	396.7	396.7	0.0	0.0	396.7	0.0
Payment of dividends to parent	(630.0)	(630.0)	0.0	0.0	(630.0)	0.0
Equity contribution from parent	455.0	455.0	0.0	455.0	0.0	0.0
Stock-based compensation and other	0.8	0.8	0.0	0.9	(0.1)	0.0
Balance at Dec. 31, 2022	4,167.2	4,136.8	332.9	1,746.8	2,057.1	30.4
Equity
Net income attributed to common shareholder	480.6	480.6	0.0	0.0	480.6	0.0
Payment of dividends to parent	(370.0)	(370.0)	0.0	0.0	(370.0)	0.0
Equity contribution from parent	805.0	805.0	0.0	805.0	0.0	0.0
Stock-based compensation and other	0.7	0.7	0.0	0.6	0.1	0.0
Balance at Dec. 31, 2023	$ 5,083.5	$ 5,053.1	$ 332.9	$ 2,552.4	$ 2,167.8	$ 30.4

XML

Summary of Significant Accounting Policies

12 Months Ended

Dec. 31, 2023

Accounting Policies [Abstract]

SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES

SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES

(a) Nature of Operations—We are an electric, natural gas, and steam utility company that serves electric and natural gas customers in Wisconsin, and steam customers in metropolitan Milwaukee, Wisconsin. WEC Energy Group owns all of our outstanding common stock.

As used in these notes, the term "financial statements" refers to the consolidated financial statements. This includes the income statements, balance sheets, statements of cash flows, and statements of equity, unless otherwise noted. On our financial statements, we consolidate VIEs of which we are the primary beneficiary.

These financial statements reflect our proportionate interests in certain jointly owned utility facilities. See Note 9, Jointly Owned Utility Facilities, for more information.

(b) Basis of Presentation—We prepare our financial statements in conformity with GAAP. We make estimates and assumptions that affect the reported amounts of assets and liabilities, the disclosure of contingent assets and liabilities at the date of the financial statements, and the reported amounts of revenues and expenses during the reporting period. Actual results may differ from these estimates.

(c) Cash and Cash Equivalents—Cash and cash equivalents include marketable debt securities with an original maturity of three months or less.

(d) Operating Revenues—The following discussion includes our significant accounting policies related to operating revenues. For additional required disclosures on disaggregation of operating revenues, see Note 5, Operating Revenues.

Revenues from Contracts with Customers

Electric Utility Operating Revenues

Electricity sales to residential and commercial and industrial customers are generally accomplished through requirements contracts, which provide for the delivery of as much electricity as the customer needs. These contracts represent discrete deliveries of electricity and consist of one distinct performance obligation satisfied over time, as the electricity is delivered and consumed by the customer simultaneously. For our residential and commercial and industrial customers, our performance obligation is bundled to consist of both the sale and the delivery of the electric commodity.

The transaction price of the performance obligations for residential and commercial and industrial customers is valued using the rates, charges, terms, and conditions of service included in our tariffs, which have been approved by the PSCW. These rates often have a fixed component customer charge and a usage-based variable component charge. We recognize revenue for the fixed component customer charge monthly using a time-based output method. We recognize revenue for the usage-based variable component charge using an output method based on the quantity of electricity delivered each month. Our retail electric rates in Wisconsin include base amounts for fuel and purchased power costs, which also impact our revenues. The electric fuel rules set by the PSCW allow us to defer, for subsequent rate recovery or refund, under- or over-collections of actual fuel and purchased power costs beyond a 2% price variance from the costs included in the rates charged to customers. We monitor the deferral of under-collected costs to ensure that it does not cause us to earn a greater ROE than authorized by the PSCW. In addition, our residential tariffs include a mechanism for cost recovery or refund of uncollectible expense based on the difference between actual uncollectible write-offs and the amounts recovered in rates.

Wholesale customers who resell power can choose to either bundle capacity and electricity services together under one contract with a supplier or purchase capacity and electricity separately from multiple suppliers. Furthermore, wholesale customers can choose to have us provide generation to match the customer's load, similar to requirements contracts, or they can purchase specified quantities of electricity and capacity. Contracts with wholesale customers that include capacity bundled with the delivery of electricity contain two performance obligations, as capacity and electricity are often transacted separately in the marketplace at the wholesale level. When recognizing revenue associated with these contracts, the transaction price is allocated to each performance obligation based on its relative standalone selling price. Revenue is recognized as control of each individual component is transferred to the customer. Electricity is the primary product sold by our electric operations and represents a single performance

obligation satisfied over time through discrete deliveries to a customer. Revenue from electricity sales is generally recognized as units are produced and delivered to the customer within the production month. Capacity represents the reservation of an electric generating facility and conveys the ability to call on a plant to produce electricity when needed by the customer. The nature of our performance obligation as it relates to capacity is to stand ready to deliver power. This represents a single performance obligation transferred over time, which generally represents a monthly obligation. Accordingly, capacity revenue is recognized on a monthly basis.

The transaction price of the performance obligations for wholesale customers is valued using the rates, charges, terms, and conditions of service, which have been approved by the FERC. These wholesale rates include recovery of fuel and purchased power costs from customers on a one-for-one basis. For the majority of our wholesale customers, the price billed for energy and capacity is a formula-based rate. Formula-based rates initially set a customer's current year rates based on the previous year’s expenses. This is a predetermined formula derived from the utility’s costs and a reasonable rate of return. Because these rates are eventually trued up to reflect actual current-year costs, they represent a form of variable consideration in certain circumstances. The variable consideration is estimated and recognized over time as wholesale customers receive and consume the capacity and electricity services.

We are an active participant in the MISO Energy Markets, where we bid our generation into the Day Ahead and Real Time markets and procure electricity for our retail and wholesale customers at prices determined by the MISO Energy Markets. Purchase and sale transactions are recorded using settlement information provided by MISO. These purchase and sale transactions are accounted for on a net hourly position. Net purchases in a single hour are recorded as purchased power in cost of sales and net sales in a single hour are recorded as resale revenues on our income statements. For resale revenues, our performance obligation is created only when electricity is sold into the MISO Energy Markets.

For all of our customers, consistent with the timing of when we recognize revenue, customer billings generally occur on a monthly basis, with payments typically due in full within 30 days.

Natural Gas Utility Operating Revenues

We recognize natural gas utility operating revenues under requirements contracts with residential, commercial and industrial, and transportation customers served under our tariffs. Tariffs provide our customers with the standard terms and conditions, including rates, related to the services offered. Requirements contracts provide for the delivery of as much natural gas as the customer needs. These requirements contracts represent discrete deliveries of natural gas and constitute a single performance obligation satisfied over time. Our performance obligation is both created and satisfied with the transfer of control of natural gas upon delivery to the customer. For most of our customers, natural gas is delivered and consumed by the customer simultaneously. A performance obligation can be bundled to consist of both the sale and the delivery of the natural gas commodity. In Wisconsin, our customers can purchase the commodity from a third party. In this case, the performance obligation only includes the delivery of the natural gas to the customer.

The transaction price of the performance obligations for our natural gas customers is valued using the rates, charges, terms, and conditions of service included in our tariffs, which have been approved by the PSCW. These rates often have a fixed component customer charge and a usage-based variable component charge. We recognize revenue for the fixed component customer charge monthly using a time-based output method. We recognize revenue for the usage-based variable component charge using an output method based on natural gas delivered each month.

Our tariffs include various rate mechanisms that allow us to recover or refund changes in prudently incurred costs from rate case-approved amounts. Our rates include a one-for-one recovery mechanism for natural gas commodity costs. Under normal circumstances, we defer any difference between actual natural gas costs incurred and costs recovered through rates as a current asset or liability. The deferred balance is returned to or recovered from customers at intervals throughout the year. However, as a result of the extreme weather in the Midwest in February 2021, the cost of gas purchased for our natural gas customers was temporarily driven significantly higher than our normal winter weather expectations. See Note 24, Regulatory Environment, for more information on the recovery of these high natural gas costs.

In addition, our residential tariffs include a mechanism for cost recovery or refund of uncollectible expense based on the difference between actual uncollectible write-offs and the amounts recovered in rates.

Consistent with the timing of when we recognize revenue, customer billings generally occur on a monthly basis, with payments typically due in full within 30 days.

Other Operating Revenues

Alternative Revenues

Alternative revenues are created from programs authorized by regulators that allow us to record additional revenues by adjusting rates in the future, usually as a surcharge applied to future billings, in response to past activities or completed events. We record alternative revenues when the regulator-specified conditions for recognition have been met. We reverse these alternative revenues as the customer is billed, at which time this revenue is presented as revenues from contracts with customers.

Our only alternative revenue program relates to the wholesale electric service that we provide to customers under market-based rates and FERC formula rates. The customer is charged a base rate each year based upon a formula using prior year actual costs and customer demand. A true-up is calculated based on the difference between the amount billed to customers for the demand component of their rates and what the actual cost of service was for the year. The true-up can result in an amount that we will recover from or refund to the customer. We consider the true-up portion of the wholesale electric revenues to be alternative revenues.

(e) Credit Losses—The following discussion includes our significant accounting policies related to credit losses. For additional required disclosures on credit losses, see Note 6, Credit Losses.

Our exposure to credit losses is related to our accounts receivable and unbilled revenue balances, which are generated from the sale of electricity and natural gas by our regulated utility operations. Our regulated utility operations are included in our utility segment. No accounts receivable and unbilled revenue balances were reported in the other segment at December 31, 2023 and 2022.

We evaluate the collectability of our accounts receivable and unbilled revenue balances considering a combination of factors. For some of our larger customers and also in circumstances where we become aware of a specific customer's inability to meet its financial obligations to us, we record a specific allowance for credit losses against amounts due in order to reduce the net recognized receivable to the amount we reasonably believe will be collected. For all other customers, we use the accounts receivable aging method to calculate an allowance for credit losses. Using this method, we classify accounts receivable into different aging buckets and calculate a reserve percentage for each aging bucket based upon historical loss rates. The calculated reserve percentages are updated on at least an annual basis, in order to ensure recent macroeconomic, political, and regulatory trends are captured in the calculation, to the extent possible. Risks identified that we do not believe are reflected in the calculated reserve percentages, are assessed on a quarterly basis to determine whether further adjustments are required.

We monitor our ongoing credit exposure through active review of counterparty accounts receivable balances against contract terms and due dates. Our activities include timely account reconciliation, dispute resolution and payment confirmation. To the extent possible, we work with customers with past due balances to negotiate payment plans, but will disconnect customers for non-payment as allowed by the PSCW, if necessary, and employ collection agencies and legal counsel to pursue recovery of defaulted receivables. For our larger customers, detailed credit review procedures may be performed in advance of any sales being made. We sometimes require letters of credit, parental guarantees, prepayments or other forms of credit assurance from our larger customers to mitigate credit risk.

(f) Materials, Supplies, and Inventories—Our inventories as of December 31 consisted of:

(in millions)	2023		2022
Materials and supplies	$	186.6	$	150.6
Fossil fuel	74.5		62.7
Natural gas in storage	49.5		79.6
Total	$	310.6	$	292.9

Substantially all materials and supplies, fossil fuel, and natural gas in storage inventories are recorded using the weighted-average cost method of accounting.

(g) Regulatory Assets and Liabilities—The economic effects of regulation can result in regulated companies recording costs and revenues that are allowed in the ratemaking process in a period different from the period they would have been recognized by a nonregulated company. When this occurs, regulatory assets and regulatory liabilities are recorded on the balance sheet. Regulatory

assets represent deferred costs probable of recovery from customers that would have otherwise been charged to expense. Regulatory liabilities represent amounts that are expected to be refunded to customers in future rates or future costs already collected from customers in rates.

The recovery or refund of regulatory assets and liabilities is based on specific periods determined by our regulators or occurs over the normal operating period of the related assets and liabilities. If a previously recorded regulatory asset is no longer probable of recovery, the regulatory asset is reduced to the amount considered probable of recovery, and the reduction is charged to expense in the current period. See Note 7, Regulatory Assets and Liabilities, for more information.

(h) Property, Plant, and Equipment—We record property, plant, and equipment at cost. Cost includes material, labor, overhead, and both debt and equity components of AFUDC. Additions to and significant replacements of property are charged to property, plant, and equipment at cost; minor items are charged to other operation and maintenance expense. The cost of depreciable utility property less salvage value is charged to accumulated depreciation when property is retired.

We record straight-line depreciation expense over the estimated useful life of utility property using depreciation rates approved by the PSCW that include estimates for salvage value and removal costs. Annual utility composite depreciation rates were 3.03%, 3.06%, and 3.09% in 2023, 2022, and 2021, respectively.

We capitalize certain costs related to software developed or obtained for internal use and record these costs to amortization expense over the estimated useful life of the related software, which ranges from 3 to 15 years. If software is retired prior to being fully amortized, the difference is recorded as a loss on the income statement.

Third parties reimburse us for all or a portion of expenditures for certain capital projects. Such contributions in aid of construction costs are recorded as a reduction to property, plant, and equipment.

See Note 8, Property, Plant, and Equipment, for more information.

(i) Allowance for Funds Used During Construction—AFUDC is included in utility plant accounts and represents the cost of borrowed funds (AFUDC-Debt) used during plant construction, and a return on shareholders' capital (AFUDC-Equity) used for construction purposes. AFUDC-Debt is recorded as a reduction of interest expense, and AFUDC-Equity is recorded in other income, net.

Approximately 50% of our retail jurisdictional CWIP expenditures are subject to the AFUDC calculation. Our average AFUDC retail rates were 8.45%, 8.68%, and 8.68% for 2023, 2022, and 2021, respectively. Our average AFUDC wholesale rates were 6.70%, 5.35%, and 1.79% for 2023, 2022, and 2021, respectively.

We recorded the following AFUDC for the years ended December 31:

(in millions)	2023		2022		2021
AFUDC-Debt	$	13.0	$	6.9	$	2.9
AFUDC-Equity	41.0		18.8		7.9

(j) Asset Impairment—Intangible assets with indefinite lives are subject to an annual impairment test. Interim impairment tests are performed when impairment indicators are present. At December 31, 2023 and 2022, we had $12.1 million and $9.1 million, respectively, of indefinite-lived intangible assets consisting of spectrum frequencies purchased in 2022 and 2023. The spectrum frequencies enable us to transmit data and voice communications over a wavelength dedicated to us throughout our service territory. These indefinite-lived intangible assets are included in other long-term assets on our balance sheets. An impairment loss is recognized when the carrying amount of an asset is not recoverable and exceeds its fair value. An impairment loss is measured as the excess of the carrying amount of the intangible asset over its fair value. No impairment losses were recorded for our indefinite-lived intangible assets during the years ended December 31, 2023 and 2022.

We periodically assess the recoverability of certain long-lived assets when factors indicate the carrying value of such assets may be impaired or such assets are planned to be sold. Long-lived assets that would be subject to an impairment assessment generally include any assets within regulated operations that may not be fully recovered from our customers as a result of regulatory decisions that will be made in the future. An impairment loss is recognized when the carrying amount of an asset is not recoverable and exceeds its fair value. The carrying amount of an asset is not recoverable if it exceeds the sum of the undiscounted cash flows

expected to result from the use and eventual disposition of the asset. An impairment loss is measured as the excess of the carrying amount of the asset over its fair value.

We assess the likelihood of a disallowance of part of the cost of recently completed plant by considering factors such as applicable regulatory environment changes, our own recent rate orders, as well as recent rate orders of other regulated entities in similar jurisdictions. When it becomes probable that part of the cost of recently completed plant will be disallowed for rate-making purposes, we assess whether a reasonable estimate of the amount of the disallowance can be made. The estimated amount of the probable disallowance will then be deducted from the reported cost of the plant and recognized as an impairment loss.

When it becomes probable that a generating unit will be retired before the end of its useful life, we assess whether the generating unit meets the criteria for abandonment accounting. Generating units that are considered probable of abandonment are expected to cease operations in the near term, significantly before the end of their original estimated useful lives. If a generating unit meets the applicable criteria to be considered probable of abandonment, and the unit has been abandoned, we assess the likelihood of recovery of the remaining net book value of that generating unit at the end of each reporting period. If it becomes probable that regulators will disallow full recovery as well as a return on the remaining net book value of a generating unit that is either abandoned or probable of being abandoned, an impairment loss may be required. An impairment loss would be recorded if the remaining net book value of the generating unit is greater than the present value of the amount expected to be recovered from ratepayers, using an incremental borrowing rate. See Note 7, Regulatory Assets and Liabilities, and Note 8, Property, Plant, and Equipment, for more information.

(k) Asset Retirement Obligations—We recognize, at fair value, legal obligations associated with the retirement of long-lived assets that result from the acquisition, construction, development, and normal operation of the assets. An ARO liability is recorded, when incurred, for these obligations as long as the fair value can be reasonably estimated, even if the timing or method of settling the obligation is unknown. The associated retirement costs are capitalized as part of the related long-lived asset and are depreciated over the useful life of the asset. The ARO liabilities are accreted each period using the credit-adjusted risk-free interest rates associated with the expected settlement dates of the AROs. These rates are determined when the obligations are incurred. Subsequent changes resulting from revisions to the timing or the amount of the original estimate of undiscounted cash flows are recognized as an increase or a decrease to the carrying amount of the liability and the associated capitalized retirement costs. We recognize regulatory assets or liabilities for the timing differences between when we recover an ARO in rates and when we recognize the associated retirement costs. See Note 10, Asset Retirement Obligations, for more information.

(l) Stock-Based Compensation—Our employees participate in the WEC Energy Group stock-based compensation plans. In accordance with the Omnibus Stock Incentive Plan, WEC Energy Group provides long-term incentives through its equity interests to its non-employee directors, officers, and other key employees. The plan provides for the granting of stock options, restricted stock, performance shares, and other stock-based awards. Awards may be paid in WEC Energy Group common stock, cash, or a combination thereof. In addition to those shares of WEC Energy Group common stock that were subject to awards outstanding as of May 6, 2021, when the plan was last approved by shareholders, 9.0 million shares of WEC Energy Group common stock were reserved for issuance under the plan.

Stock-based compensation expense is allocated to us based on the outstanding awards held by our employees and our allocation of labor costs. Awards classified as equity awards are measured based on their grant-date fair value. Awards classified as liability awards are recorded at fair value each reporting period. We account for forfeitures as they occur, rather than estimating potential future forfeitures and recording them over the vesting period.

Stock Options

Our employees are granted WEC Energy Group non-qualified stock options that generally vest on a cliff-basis after three years. The exercise price of a stock option under the plan cannot be less than 100% of the fair market value of WEC Energy Group common stock on the grant date. Historically, all stock options have been granted with an exercise price equal to the fair market value of WEC Energy Group common stock on the date of the grant. Options vest immediately upon retirement, death, or disability; however, they may not be exercised within six months of the grant date except in connection with certain termination of employment events following a change in control. Options expire no later than 10 years from the date of grant.

WEC Energy Group stock options are classified as equity awards. The fair value of each stock option was calculated using a binomial option-pricing model. The following table shows the estimated weighted-average fair value per stock option granted to our employees along with the weighted-average assumptions used in the valuation models:

	2023			2022			2021
Stock options granted	30,495			51,511			60,108
Estimated weighted-average fair value per stock option	$	19.58		$	14.71		$	13.20
Assumptions used to value the options:
Risk-free interest rate	3.8% – 4.8%			0.2% – 1.6%			0.1% – 0.9%
Dividend yield	3.2		%	3.2		%	2.9		%
Expected volatility	22.0		%	21.0		%	21.0		%
Expected life (years)	8.3			8.7			8.7

The risk-free interest rate was based on the United States Treasury interest rate with a term consistent with the expected life of the stock options. The dividend yield was based on WEC Energy Group's dividend rate at the time of the grant and historical stock prices. Expected volatility and expected life assumptions were based on WEC Energy Group's historical experience.

Restricted Shares

WEC Energy Group restricted shares granted to our employees have a vesting period of three years with one-third of the award vesting on each anniversary of the grant date. The restricted shares are classified as equity awards.

Performance Units

Officers and other key employees are granted performance units under the WEC Energy Group Performance Unit Plan. All grants of performance units are settled in cash and are accounted for as liability awards accordingly. Performance units accrue forfeitable dividend equivalents in the form of additional performance units. The fair value of the performance units reflects our estimate of the final expected value of the awards, which is based on WEC Energy Group's stock price and performance achievement under the terms of the award. Stock-based compensation costs are generally recorded over the performance period, which is three years.

The ultimate number of units that will be awarded is dependent on WEC Energy Group's total shareholder return (stock price appreciation plus dividends) as compared to the total shareholder return of a peer group of companies over three years, as well as other performance metrics, as may be determined by the Compensation Committee. Under the terms of awards granted prior to 2023, participants may earn between 0% and 175% of the performance unit award based on WEC Energy Group's total shareholder return. Pursuant to the plan terms governing these awards, these percentages can be adjusted upwards or downwards by up to 10% based on WEC Energy Group's performance against additional performance measures, if any, adopted by the Compensation Committee.

The WEC Energy Group Performance Unit Plan was amended and restated, effective January 1, 2023. In accordance with the amended plan, the Compensation Committee selected multiple performance measures that will be weighted to determine the ultimate payout for the awards granted in 2023 and 2024. The ultimate number of units awarded will be based on WEC Energy Group's total shareholder return compared to the total shareholder return of a peer group of companies over three years (55%), and WEC Energy Group's performance against the weighted average authorized ROE of all of its utility subsidiaries (45%). In addition, the Compensation Committee selected the level of WEC Energy Group's stock price to earnings ratio compared to its peer companies as a performance measure that can increase the payout by up to 25%. In no event can the performance unit payout be greater than 200% of the target award.

See Note 11, Common Equity, for more information on WEC Energy Group's stock-based compensation plans.

(m) Leases—We recognize a right of use asset and lease liability for operating and finance leases with a term of greater than one year. As a policy election, we account for each lease component separately from the nonlease components of a contract.

We are currently party to several easement agreements that allow us access to land we do not own for the purpose of constructing and maintaining certain electric power and natural gas equipment. The majority of payments we make related to easements relate

to our renewable generating facilities. We have not classified our easements as leases because we view the entire parcel of land specified in our easement agreements to be the identified asset, not just that portion of the parcel that contains our easement. As such, we have concluded that we do not control the use of an identified asset related to our easement agreements, nor do we obtain substantially all of the economic benefits associated with these shared-use assets.

See Note 15, Leases, for more information.

(n) Income Taxes—We follow the liability method in accounting for income taxes. Accounting guidance for income taxes requires the recording of deferred assets and liabilities to recognize the expected future tax consequences of events that have been reflected in our financial statements or tax returns and the adjustment of deferred tax balances to reflect tax rate changes. We are required to assess the likelihood that our deferred tax assets would expire before being realized. If we conclude that certain deferred tax assets are likely to expire before being realized, a valuation allowance would be established against those assets. GAAP requires that, if we conclude in a future period that it is more likely than not that some or all of the deferred tax assets would be realized before expiration, we reverse the related valuation allowance in that period. Any change to the allowance, as a result of a change in judgment about the realization of deferred tax assets, is reported in income tax expense.

ITCs associated with regulated operations are deferred and amortized over the life of the assets. PTCs are recognized in the period in which such credits are generated. The amount of the credit is based upon power production from our qualifying generation facilities. We are included in WEC Energy Group's consolidated federal and state income tax returns. In accordance with our tax allocation agreement with WEC Energy Group, we are allocated income tax payments and refunds based upon the benefit for loss method, where attributes are realized when WEC Energy Group is able to realize them.

We recognize interest and penalties accrued related to unrecognized tax benefits in income tax expense in our income statements.

The IRA contains a tax credit transferability provision that allows us to sell PTCs produced after December 31, 2022, to third parties. In September 2023, under this transferability provision, WEC Energy Group entered into an agreement to sell substantially all of our 2023 PTCs to a third party. We elect to account for tax credits transferred under the scope of ASC 740. We include the discount from the sale of tax credits as a component of income tax expense. We will also include any expected proceeds from the sale of tax credits in the evaluation of the realizability of deferred tax assets related to PTCs. The sale of tax credits is presented in the operating activities section of the statements of cash flows consistent with the presentation of cash taxes paid.

In April 2023, the IRS issued Revenue Procedure 2023-15, which provides a safe harbor method of accounting that taxpayers may use to determine whether expenses to repair, maintain, replace, or improve natural gas transmission and distribution property must be capitalized for tax purposes. We are currently evaluating the impact this guidance may have on our financial statements and related disclosures.

See Note 16, Income Taxes, for more information.

(o) Fair Value Measurements—Fair value is the price that would be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants at the measurement date (exit price).

Fair value accounting rules provide a fair value hierarchy that prioritizes the inputs used to measure fair value. The hierarchy gives the highest priority to unadjusted quoted prices in active markets for identical assets or liabilities (Level 1 measurement) and the lowest priority to unobservable inputs (Level 3 measurement). The three levels of the fair value hierarchy are defined as follows:

Level 1 – Quoted prices are available in active markets for identical assets or liabilities as of the reporting date. Active markets are those in which transactions for the asset or liability occur in sufficient frequency and volume to provide pricing information on an ongoing basis.

Level 2 – Pricing inputs are observable, either directly or indirectly, but are not quoted prices included within Level 1. Level 2 includes those financial instruments that are valued using external inputs within models or other valuation methods.

Level 3 – Pricing inputs include significant inputs that are generally less observable from objective sources. These inputs may be used with internally developed methods that result in management's best estimate of fair value. Level 3 instruments include those that may be more structured or otherwise tailored to customers' needs.

Assets and liabilities are classified in their entirety based on the lowest level of input that is significant to the fair value measurement. We use a mid-market pricing convention (the mid-point price between bid and ask prices) as a practical measure for valuing certain derivative assets and liabilities. We primarily use a market approach for recurring fair value measurements and attempt to use valuation techniques that maximize the use of observable inputs and minimize the use of unobservable inputs.

When possible, we base the valuations of our derivative assets and liabilities on quoted prices for identical assets and liabilities in active markets. These valuations are classified in Level 1. The valuations of certain contracts not classified as Level 1 may be based on quoted market prices received from counterparties and/or observable inputs for similar instruments. Transactions valued using these inputs are classified in Level 2. Certain derivatives, such as FTRs, are categorized in Level 3 due to the significance of unobservable or internally-developed inputs. Our FTRs are valued using MISO auction prices.

See Note 17, Fair Value Measurements, for more information.

(p) Derivative Instruments—We use derivatives as part of our risk management program to manage the risks associated with the price volatility of purchased power, generation, and natural gas costs for the benefit of our customers. Our approach is non-speculative and designed to mitigate risk. Our regulated hedging programs are approved by the PSCW.

We record derivative instruments on our balance sheets as assets or liabilities measured at fair value, unless they qualify for the normal purchases and sales exception, and are so designated. We continually assess our contracts designated as normal and will discontinue the treatment of these contracts as normal if the required criteria are no longer met. Changes in the derivative's fair value are recognized currently in earnings unless specific hedge accounting criteria are met or we receive regulatory treatment for the derivative. For most energy related physical and financial contracts in our regulated operations that qualify as derivatives, the PSCW allows the effects of fair value accounting to be offset to regulatory assets and liabilities.

We classify derivative assets and liabilities as current or long-term on our balance sheets based on the maturities of the underlying contracts. Cash flows from derivative activities are presented in the same category as the item being hedged within operating activities on our statements of cash flows.

Derivative accounting rules provide the option to present certain asset and liability derivative positions net on the balance sheets and to net the related cash collateral against these net derivative positions. We elected not to net these items. On our balance sheets, cash collateral provided to others is reflected in other current assets. See Note 18, Derivative Instruments, for more information.

(q) Guarantees—We follow the guidance of the Guarantees Topic of the FASB ASC, which requires, under certain circumstances, that the guarantor recognize a liability for the fair value of the obligation undertaken in issuing the guarantee at its inception. As of December 31, 2023, we had $26.0 million of standby letters of credit issued by financial institutions for the benefit of third parties that have extended credit to us, which automatically renew each year unless proper termination notice is given. These amounts are not reflected on our balance sheets.

(r) Employee Benefits—The costs of pension and OPEB plans are expensed over the periods during which employees render service. These costs are distributed among WEC Energy Group's subsidiaries based on current employment status and actuarial calculations, as applicable. Our regulators allow recovery in rates for our net periodic benefit cost calculated under GAAP. See Note 19, Employee Benefits, for more information.

(s) Customer Deposits and Credit Balances—When utility customers apply for new service, they may be required to provide a deposit for the service. Customer deposits are recorded within other current liabilities on our balance sheets.

Utility customers can elect to be on a budget plan. Under this type of plan, a monthly installment amount is calculated based on estimated annual usage. During the year, the monthly installment amount is reviewed by comparing it to actual usage. If necessary, an adjustment is made to the monthly amount. Annually, the budget plan is reconciled to actual annual usage. Payments in excess of actual customer usage are recorded within other current liabilities on our balance sheets.

(t) Environmental Remediation Costs—We are subject to federal and state environmental laws and regulations that in the future may require us to pay for environmental remediation at sites where we have been, or may be, identified as a potentially responsible party. Loss contingencies may exist for the remediation of hazardous substances at various potential sites, including CCR

landfills and manufactured gas plant sites. See Note 10, Asset Retirement Obligations, for more information regarding CCR landfills and Note 22, Commitments and Contingencies, for more information regarding manufactured gas plant sites.

We record environmental remediation liabilities when site assessments indicate remediation is probable, and we can reasonably estimate the loss or a range of losses. The estimate includes both our share of the liability and any additional amounts that will not be paid by other potentially responsible parties or the government. When possible, we estimate costs using site-specific information but also consider historical experience for costs incurred at similar sites. Remediation efforts for a particular site generally extend over a period of several years. During this period, the laws governing the remediation process may change, as well as site conditions, potentially affecting the cost of remediation.

We have received approval to defer certain environmental remediation costs, as well as estimated future costs, through a regulatory asset. The recovery of deferred costs is subject to the PSCW's approval.

We review our estimated costs of remediation annually for our manufactured gas plant sites and CCR landfills. We adjust the liabilities and related regulatory assets, as appropriate, to reflect the new cost estimates. Any material changes in cost estimates are adjusted throughout the year.

(u) Customer Concentrations of Credit Risk—The geographic concentration of our customers did not contribute significantly to our overall exposure to credit risk. We periodically review customers' credit ratings, financial statements, and historical payment performance and require them to provide collateral or other security as needed. Our credit risk exposure is mitigated by our recovery mechanism for uncollectible expense discussed in Note 1(d), Operating Revenues. As a result, we did not have any significant concentrations of credit risk at December 31, 2023. In addition, there were no customers that accounted for more than 10% of our revenues for the year ended December 31, 2023.

XML

Acquisitions

12 Months Ended

Dec. 31, 2023

Asset Acquisition [Abstract]

Asset Acquisition [Text Block]

ACQUISITIONS

In accordance with Topic 805: Clarifying the Definition of a Business (ASU 2017-01), transactions are evaluated and are accounted for as acquisitions of assets or businesses, and transaction costs are capitalized in asset acquisitions. It was determined that all of the below acquisitions met the criteria of asset acquisitions.

Acquisitions of Electric Generation Facilities in Wisconsin

In June 2023, we completed the acquisition of 100 MWs of West Riverside's nameplate capacity, in the first of two potential option exercises. West Riverside is a commercially operational dual fueled combined cycle generation facility in Beloit, Wisconsin. Our investment was $95.3 million. In addition, WPS filed a request with the PSCW in September 2023 to exercise a second option to acquire an additional 100 MWs of West Riverside's nameplate capacity. As it did with the first option, in October 2023, WPS filed for approval to assign its ownership interest pursuant to this second option to us. If these approvals are obtained, our incremental share of this investment is expected to be approximately $100 million, with the transaction expected to close in 2024.

In January 2023, we, along with WPS, completed the acquisition of Whitewater, a commercially operational 236.5 MW dual fueled (natural gas and low sulfur fuel oil) combined cycle electrical generation facility in Whitewater, Wisconsin. Our share of the cost of this facility was $38.0 million for 50% of the capacity.

XML

Disposition

12 Months Ended

Dec. 31, 2023

Discontinued Operations and Disposal Groups [Abstract]

DISPOSITIONS

DISPOSITION

Sale of Real Estate

In June 2023, we sold approximately 192 acres of real estate at our former Pleasant Prairie power plant site that was no longer being utilized in our operations, for $23.0 million, which is net of closing costs. As a result of the sale, a pre-tax gain in the amount of $22.2 million was recorded within other operation and maintenance expense on our income statement. The book value of the real estate included in the sale was not material and, therefore, was not presented as held for sale.

XML

Related Parties

12 Months Ended

Dec. 31, 2023

Related Party Transactions [Abstract]

RELATED PARTIES

RELATED PARTIES

We routinely enter into transactions with related parties, including WEC Energy Group, its other subsidiaries, ATC, and other affiliated entities.

We provide and receive services, property, and other items of value to and from our parent, WEC Energy Group, and other subsidiaries of WEC Energy Group pursuant to an AIA that became effective in 2017. The AIA was approved by the appropriate regulators, including the PSCW. In accordance with the AIA, WBS provides several categories of services to us (including financial, human resource, and administrative services). As required by FERC regulations for centralized service companies, WBS renders services at cost. Services provided by any regulated subsidiary of WEC Energy Group to another regulated subsidiary or WBS are provided at cost, and any services provided by a regulated subsidiary to a nonregulated subsidiary of WEC Energy Group are provided at the greater of cost or fair market value.

We pay ATC for transmission and other related services it provides. In addition, we provide a variety of operational, maintenance, and project management work for ATC, which is reimbursed by ATC. Services are billed to and from ATC under agreements approved by the PSCW, at each of our fully allocated costs. We are also required to initially fund the construction of transmission infrastructure upgrades needed for new generation projects. ATC owns these transmission assets and reimburses us for these costs when the new generation is placed in service.

Our balance sheets included the following receivables and payables for services provided to or received from ATC:

(in millions)	December 31, 2023		December 31, 2022
Accounts receivable
Services provided to ATC	$	0.9	$	0.7
Amounts due from ATC for transmission infrastructure upgrades (1)	39.5		23.3
Accounts payable
Services received from ATC	36.7		20.0

(1)     The transmission infrastructure upgrades were primarily related to the construction of our renewable energy projects.

The following table shows activity associated with our related party transactions for the years ended December 31:

(in millions)	2023		2022		2021
Transactions with WPS
Natural gas related purchases from WPS (1)	$	1.3	$	3.3	$	2.9
Charges to WPS for services and other items (2)	16.2		13.3		11.8
Charges from WPS for services and other items (2)	11.3		10.7		9.4
Transactions with WG
Natural gas related purchases from WG (1)	19.7		6.2		5.9
Natural gas related sales to WG (1)	0.3		1.3		0.3
Charges to WG for services and other items (2)	38.3		39.5		40.4
Charges from WG for services and other items (2)	27.9		29.8		29.7
Transactions with UMERC
Charges to UMERC for services and other items (2)	11.8		13.7		10.5
Charges from UMERC for services and other items (2)	2.0		1.2		1.2
Transactions with Bluewater
Charges from Bluewater for storage service fees (3)	17.2		14.8		13.6
Charges from Bluewater for other operating fees (3)	4.1		3.3		1.4
Natural gas related sales to Bluewater (1)	2.8		2.7		2.6
Charges to Bluewater for services and other items (2)	2.7		2.7		3.0
Transactions with We Power
Lease payments and other lease-related charges from We Power (4)	422.0		412.6		406.0
Charges to We Power for services and other items (2)	7.8		4.2		6.7
Transactions with WBS
Charges to WBS for services and other items (2)	41.1		49.5		67.8		(5)
Charges from WBS for services and other items (2)	113.3		123.1		123.8
Transactions with ATC
Charges to ATC for services and construction	8.1		9.3		14.9
Charges from ATC for network transmission services	248.8		239.3		240.4
Net refund (payment) from (to) ATC related to FERC ROE orders	—		(0.1)		5.1

(1)    Includes amounts related to the purchase or sale of natural gas and/or pipeline capacity.

(2)    Includes amounts charged for services, pass through costs, asset and liability transfers, and other items in accordance with the approved AIA.

(3)    We have a long-term service agreement with a wholly owned subsidiary of Bluewater that was previously approved by the PSCW. Bluewater owns natural gas storage facilities in Michigan and provides a portion of our current storage needs.

(4)    We make lease payments to We Power for PWGS Units 1 and 2 and ERGS Units 1 and 2. See Note 15, Leases, for more information.

(5)     Includes $11.3 million for the transfer of certain software assets to WBS.

XML

Operating Revenues

12 Months Ended

Dec. 31, 2023

Revenue from Contract with Customer [Abstract]

OPERATING REVENUES

OPERATING REVENUES

For more information about our significant accounting policies related to operating revenues, see Note 1(d), Operating Revenues.

Disaggregation of Operating Revenues

The following tables present our operating revenues disaggregated by revenue source for our utility segment. We do not have any revenues associated with our other segment. We disaggregate revenues into categories that depict how the nature, amount, timing, and uncertainty of revenues and cash flows are affected by economic factors. Revenues are further disaggregated by electric and natural gas operations and then by customer class. Each customer class within our electric and natural gas operations has different expectations of service, energy and demand requirements, and can be impacted differently by regulatory activities within their jurisdictions.

	Year Ended December 31
(in millions)	2023		2022		2021
Wisconsin Electric Power Company
Electric utility	$	3,540.2	$	3,448.7	$	3,171.6
Natural gas utility	489.8		606.8		474.2
Total revenues from contracts with customers	4,030.0		4,055.5		3,645.8
Other operating revenues	15.0		14.8		18.7
Total operating revenues	$	4,045.0	$	4,070.3	$	3,664.5

Revenues from Contracts with Customers

Electric Utility Operating Revenues

The following table disaggregates electric utility operating revenues into customer class:

	Year Ended December 31
(in millions)	2023		2022		2021
Residential	$	1,480.6	$	1,376.3	$	1,306.2
Small commercial and industrial	1,177.2		1,095.0		1,019.7
Large commercial and industrial	616.0		629.1		568.6
Other	21.1		20.4		20.2
Total retail revenues	3,294.9		3,120.8		2,914.7
Wholesale	40.9		58.4		71.0
Resale	173.7		224.3		148.2
Steam	25.2		28.4		28.7
Other utility revenues	5.5		16.8		9.0
Total electric utility operating revenues	$	3,540.2	$	3,448.7	$	3,171.6

Natural Gas Utility Operating Revenues

The following table disaggregates natural gas utility operating revenues into customer class:

	Year Ended December 31
(in millions)	2023		2022		2021
Residential	$	323.3	$	397.8	$	309.1
Commercial and industrial	148.2		193.7		141.9
Total retail revenues	471.5		591.5		451.0
Transportation	21.6		17.8		17.3
Other utility revenues (1)	(3.3)		(2.5)		5.9
Total natural gas utility operating revenues	$	489.8	$	606.8	$	474.2

(1)    Includes the revenues subject to our purchased gas recovery mechanism, which fluctuate based on actual natural gas costs incurred, compared with the recovery of natural gas costs that were anticipated in rates.

Other Operating Revenues

Other operating revenues consist of the following:

	Year Ended December 31
(in millions)	2023		2022		2021
Late payment charges	$	12.2	$	12.1	$	13.3
Rental revenues	2.5		2.5		3.0
Alternative revenues	0.3		0.2		2.4
Total other operating revenues	$	15.0	$	14.8	$	18.7

XML

Credit Losses

12 Months Ended

Dec. 31, 2023

Credit Loss [Abstract]

CREDIT LOSSES

CREDIT LOSSES

The table below shows our gross third-party receivable balances and related allowance for credit losses.

(in millions)	December 31, 2023			December 31, 2022
Accounts receivable and unbilled revenues	$	617.5		$	632.3
Allowance for credit losses	44.5			49.7
Accounts receivable and unbilled revenues, net (1)	$	573.0		$	582.6
Total accounts receivable, net – past due greater than 90 days (1)	$	37.2		$	35.8
Past due greater than 90 days – collection risk mitigated by regulatory mechanisms (1)	94.1		%	97.5		%

(1)    Our exposure to credit losses for certain regulated utility customers is mitigated by a regulatory mechanism we have in place. Specifically, our residential tariffs include a mechanism for cost recovery or refund of uncollectible expense based on the difference between actual uncollectible write-offs and the amounts recovered in rates. As a result, at December 31, 2023, $342.5 million, or 59.8%, of our net accounts receivable and unbilled revenues balance had regulatory protections in place to mitigate the exposure to credit losses.

A rollforward of the allowance for credit losses is included below:

	Year Ended December 31
(in millions)	2023		2022		2021
Balance at January 1	$	49.7	$	51.4	$	59.3
Provision for credit losses	23.8		27.3		24.8
Provision for credit losses deferred for future recovery or refund	45.7		34.0		(0.3)
Write-offs charged against the allowance	(94.1)		(83.4)		(47.6)
Recoveries of amounts previously written off	19.4		20.4		15.2
Balance at December 31	$	44.5	$	49.7	$	51.4

The allowance for credit losses decreased during the year ended December 31, 2023, primarily related to lower customer energy costs (driven by the warmer weather during the fourth quarter of 2023 when compared to the same quarter in 2022 and lower natural gas prices), which contributed to a reduction in past due accounts receivable balances and a related decrease in the allowance for credit losses. Customer write-offs also contributed to the decrease in the allowance for credit losses. After a customer is disconnected for a period of time without payment on their account, we will write off that customer balance.

The allowance for credit losses decreased during the year ended December 31, 2022, driven by customer write-offs related to collection practices returning to pre-pandemic levels in 2021, including the restoration of our ability to disconnect customers. Partially offsetting the decrease in the allowance for credit losses, we believe that the high energy costs that customers were seeing, which were driven by high natural gas prices, contributed to higher past due accounts receivable balances and a related increase in the allowance of credit losses.

The allowance for credit losses decreased during the year ended December 31, 2021, primarily related to normal collection practices resuming in April 2021. Higher year-over-year natural gas prices drove an increase in gross accounts receivable balances, partially offsetting the decrease in the allowance for credit losses attributed to collection efforts.

XML

Regulatory Assets and Liabilities

12 Months Ended

Dec. 31, 2023

Regulatory Assets and Liabilities Disclosure [Abstract]

REGULATORY ASSETS AND LIABILITIES

REGULATORY ASSETS AND LIABILITIES

The following regulatory assets were reflected on our balance sheets as of December 31:

(in millions)	2023		2022		See Note
Regulatory assets (1) (2)
Finance leases	$	1,109.7	$	1,072.0	15
Plant retirement related items	595.5		632.7
Income tax related items	373.1		382.1		16
Pension and OPEB costs (3)	348.9		337.2		19, 24
SSR (4)	113.2		123.5
Securitization	85.9		92.4		21
Uncollectible expense	62.1		16.4		6
Derivatives	45.2		40.3		1(p)
AROs	41.2		41.1		1(k), 10
Energy efficiency programs (5)	23.3		17.7
We Power generation (6)	4.7		21.6
Other, net	57.9		40.5
Total regulatory assets	$	2,860.7	$	2,817.5

(1)    Based on prior and current rate treatment, we believe it is probable that we will continue to recover from customers the regulatory assets in this table. In accordance with GAAP, our regulatory assets do not include the allowance for ROE that is capitalized for regulatory purposes. This allowance was $16.5 million and $14.7 million at December 31, 2023 and 2022, respectively.

(2)    As of December 31, 2023, we had $1.9 million of regulatory assets not earning a return, $4.7 million of regulatory assets earning a return based on short-term interest rates, and $129.7 million of regulatory assets earning a return based on long-term interest rates. The regulatory assets not earning a return relate to certain environmental remediation costs. The other regulatory assets in the table either earn a return at our weighted average cost of capital or the cash has not yet been expended, in which case the regulatory assets are offset by liabilities.

(3)    Primarily represents the unrecognized future pension and OPEB costs related to our defined benefit pension and OPEB plans. We are authorized recovery of these regulatory assets over the average remaining service life of each plan.

(4)    This regulatory asset relates to our 2014 announcement to retire the PIPP. Despite our intent to retire the PIPP, MISO designated the PIPP as an SSR, which meant the PIPP's operation was necessary for reliability, and the plant could not be shut down until new generation or transmission facilities were built. In December 2014, the PSCW authorized escrow accounting for our SSR revenues because of the fluctuations in the actual revenues we received under the PIPP SSR agreements. The rate order we received from the PSCW in December 2019 authorized recovery of this SSR regulatory asset over a 15-year period that began on January 1, 2020.

(5)    Represents amounts recoverable from customers related to programs designed to meet energy efficiency standards.

(6)    Represents amounts recoverable from customers related to our costs of the generating units leased from We Power, including subsequent capital additions.

The following regulatory liabilities were reflected on our balance sheets as of December 31:

(in millions)	2023		2022		See Note
Regulatory liabilities
Removal costs (1)	$	758.9	$	718.1
Income tax related items	683.5		716.1		16
Pension and OPEB benefits (2)	124.0		144.4		19, 24
Electric transmission costs (3)	23.9		0.2
Energy efficiency programs (4)	10.6		1.0
Derivatives	4.5		39.1		1(p)
Other, net	31.3		19.9
Total regulatory liabilities	$	1,636.7	$	1,638.8
Balance sheet presentation
Other current liabilities	$	5.3	$	1.4
Regulatory liabilities	1,631.4		1,637.4
Total regulatory liabilities	$	1,636.7	$	1,638.8

(1)    Represents amounts collected from customers to cover the future cost of property, plant, and equipment removals that are not legally required. Legal obligations related to the removal of property, plant, and equipment are recorded as AROs. See Note 10, Asset Retirement Obligations, for more information on our legal obligations.

(2)    Primarily represents the unrecognized future pension and OPEB benefits related to our defined benefit pension and OPEB plans. We will amortize these regulatory liabilities into net periodic benefit cost over the average remaining service life of each plan.

(3)    In accordance with the PSCW's approval of escrow accounting for our ATC and MISO network transmission expenses, we defer as a regulatory asset or liability the difference between actual transmission costs and those included in rates until recovery or refund is authorized in a future rate proceeding.

(4)    Represents amounts refundable to customers related to programs designed to meet energy efficiency standards.

Pleasant Prairie Power Plant

The Pleasant Prairie power plant was retired on April 10, 2018. The net book value of this plant was $542.4 million at December 31, 2023, representing book value less cost of removal and accumulated depreciation. In addition, previously deferred unprotected tax benefits from the Tax Legislation related to the unrecovered balance of this plant were $16.4 million as of December 31, 2023. The net amount of $526.0 million was classified as a regulatory asset on our balance sheet at December 31, 2023 due to the retirement of the plant. This regulatory asset does not include certain other previously recorded deferred tax liabilities of $147.8 million related to the retired Pleasant Prairie power plant. Pursuant to our rate order issued by the PSCW in December 2019, we will continue to amortize this regulatory asset on a straight-line basis through 2039, using the composite depreciation rates approved by the PSCW before this plant was retired. The amortization is included in depreciation and amortization in the income statement. We also have FERC approval to continue to collect the net book value of the Pleasant Prairie power plant using the approved composite depreciation rates, in addition to a return on the remaining net book value.

We received approval from the PSCW in December 2019 to collect a full return of the net book value of the Pleasant Prairie power plant and a return on all but $100 million of the net book value. During May 2021, we securitized the remaining $100 million of the Pleasant Prairie power plant's book value, the carrying costs accrued on the $100 million during the securitization process, and the related financing fees, in accordance with a written order issued by the PSCW in November 2020. See Note 21, Variable Interest Entities, for more information on this securitization.

Presque Isle Power Plant

Pursuant to MISO's April 2018 approval of the retirement of the PIPP, these units were retired on March 31, 2019, and the plant was reclassified to a regulatory asset on our balance sheets. After the retirement of the PIPP, a portion of the regulatory asset and related cost of removal reserve was transferred to UMERC for recovery from its retail customers. On our balance sheet, the net book value of the PIPP was $141.2 million at December 31, 2023, representing book value less cost of removal and accumulated depreciation. In addition, previously deferred unprotected tax benefits from the Tax Legislation related to our unrecovered balance of these units were $4.8 million, resulting in a net amount of $136.4 million at December 31, 2023. This regulatory asset does not

include certain other previously recorded deferred tax liabilities of $38.5 million related to the retired PIPP. Effective with our rate order issued by the PSCW in December 2019, we received approval to collect a return of and on our share of the net book value of the PIPP, and as a result, will continue to amortize the regulatory assets on a straight-line basis through 2037, using the composite depreciation rates approved by the PSCW before the units were retired. The amortization is included in depreciation and amortization in the income statement. We also have FERC approval to continue to collect the net book value of the PIPP using the approved composite depreciation rates, in addition to a return on the net book value.

XML

Property, Plant, and Equipment

12 Months Ended

Dec. 31, 2023

Property, Plant and Equipment [Abstract]

PROPERTY, PLANT, AND EQUIPMENT

PROPERTY, PLANT, AND EQUIPMENT

Property, plant, and equipment consisted of the following at December 31:

(in millions)	2023		2022
Electric – generation	$	2,721.3	$	2,200.0
Electric – distribution	6,116.7		5,822.4
Natural gas – distribution, storage, and transmission	2,059.4		1,757.0
Property, plant, and equipment to be retired	783.7		812.5
Other	1,087.0		1,044.9
Less: Accumulated depreciation	3,530.3		3,213.4
Net	9,237.8		8,423.4
CWIP	624.7		556.1
Net utility and non-utility property, plant, and equipment	9,862.5		8,979.5
Property under finance leases	3,206.8		3,248.8
Less: Accumulated amortization	1,483.8		1,509.7
Net leased facilities	1,723.0		1,739.1
Total property, plant, and equipment	$	11,585.5	$	10,718.6

Severance Liability for Plant Retirements

We have severance liabilities related to past and future plant retirements recorded in other current and other long-term liabilities on our balance sheets. Activity related to these severance liabilities for the years ended December 31 was as follows:

(in millions)	2023		2022		2021
Severance liability at January 1	$	13.5	$	3.3	$	0.7
Severance expense	1.6		10.2		3.0
Severance payments	—		—		(0.4)
Total severance liability at December 31	$	15.1	$	13.5	$	3.3

Plant to be Retired

Oak Creek Power Plant Units 5-8

As a result of a PSCW approval in December 2022 for the acquisition and construction of Darien, the retirement of OCPP Units 5-8 became probable. In early 2023, we received additional approvals for electric generation facilities, including Koshkonong and 100 MWs of West Riverside. See Note 2, Acquisitions, for more information on the West Riverside acquisition, which was completed in June 2023. OCPP Units 5 and 6 are expected to be retired by May 2024, while OCPP Units 7 and 8 are expected to be retired by late 2025. The total net book value of our ownership share of OCPP Units 5-8 was $783.7 million at December 31, 2023, which does not include deferred taxes. This amount was classified as plant to be retired within property, plant, and equipment on our balance sheet. These units are included in rate base, and we continue to depreciate them on a straight-line basis using the composite depreciation rates approved by the PSCW.

Public Service Building and Steam Tunnel Assets

During a significant rain event in May 2020, an underground steam tunnel in downtown Milwaukee flooded and steam vented into our PSB. The damage to the building and adjacent steam tunnel assets from the flooding and steam was extensive and required

significant repairs and restorations. As of December 31, 2023, we had incurred $95.3 million of costs related to these repairs and restorations. In June 2021, we received approval from the PSCW to restore the PSB and adjacent steam tunnel assets and to defer the project costs, net of insurance proceeds, as a component of rate base. As a result, we do not currently expect a significant impact to our future results of operations.

XML

Jointly Owned Utility Facilities

12 Months Ended

Dec. 31, 2023

Jointly Owned Utility Plant, Net Ownership Amount [Abstract]

JOINTLY OWNED UTILITY FACILITIES

JOINTLY OWNED UTILITY FACILITIES

We hold joint ownership interests in certain electric generating facilities. We are entitled to our share of generating capability and output of each facility equal to our respective ownership interest. We have supplied our own financing for all jointly owned projects. We pay our ownership share of additional construction costs, fuel inventory purchases, and operating expenses, unless specific agreements have been executed to limit our maximum exposure to additional costs. We record our proportionate share of significant jointly owned electric generating facilities as property, plant, and equipment on the balance sheets. In addition, our proportionate share of direct expenses for the joint operation of these plants is recorded within operating expenses in the income statements.

Information related to jointly owned utility facilities at December 31, 2023 was as follows:

Jointly-Owned Utility Facilities	Ownership		Share of Capacity (MW)	In-Service /Acquisition Date	Operating Owner	Property, Plant, and Equipment		Accumulated Depreciation		CWIP
(in millions, except for percentages and MW)
West Riverside (1) (3)	13.8	%	84.9	2023	WE	$	108.7	$	(11.3)	$	0.9
Badger Hollow II (2)	66.7	%	100.0	2023	WE	170.1		(0.3)		0.1
Weston RICE units (1)	50.0	%	65.0	2023	WPS	92.4		(1.3)		—
Whitewater (1) (4)	50.0	%	121.4	2023	WE	125.7		(93.6)		0.3

(1)    Capacity is based on rated capacity, which is the net power output under average operating conditions with equipment in an average state of repair as of a given month in a given year. Values are primarily based on the net dependable expected capacity ratings for summer 2024 established by tests and may change slightly from year to year. The summer period is the most relevant for capacity planning purposes. This is a result of continually reaching demand peaks in the summer months, primarily due to air conditioning demand.

(2)     Capacity for solar generating facilities is based on nameplate capacity, which is the maximum output that a generator should produce at continuous full power.

(3)    We acquired our ownership interest in June 2023. In September 2023, WPS filed a request with the PSCW to exercise a second option to acquire an additional 100 MWs of West Riverside's nameplate capacity. WPS subsequently filed for approval to assign its ownership interest pursuant to this second option to us. See Note 2, Acquisitions, for more information.

(4)    Effective January 1, 2023, we, along with WPS, completed the acquisition of Whitewater. See Note 2, Acquisitions, for more information.

We, along with WPS and an unaffiliated utility, received PSCW approval to construct Koshkonong, a utility-scale solar-powered electric generating facility. The project will be located in Dane County, Wisconsin and once fully constructed, we will own 75%, or 225 MWs of solar generation of this project. Commercial operation of the solar facility is targeted for 2026. Our CWIP balance for Koshkonong was not significant as of December 31, 2023.

We, along with WPS and an unaffiliated utility, received PSCW approval to construct Paris, a utility-scale solar-powered electric generating facility with a battery energy storage system. The project will be located in Kenosha County, Wisconsin and once fully constructed, we will own 75%, or 150 MWs of solar generation and 82 MWs of battery storage of this project. Commercial operation of the solar facility is targeted for 2024 and construction of the battery storage is expected to be completed in 2025. Our CWIP balance for Paris was $279.1 million as of December 31, 2023.

We, along with WPS and an unaffiliated utility, received PSCW approval to construct Darien, a utility-scale solar-powered electric generating facility. The project will be located in Rock and Walworth counties, Wisconsin and once fully constructed, we will own 75%, or 188 MWs of solar generation of this project. Commercial operation of the solar facility is targeted for 2024. Our CWIP balance for Darien was $183.8 million as of December 31, 2023.

XML

Asset Retirement Obligations

12 Months Ended

Dec. 31, 2023

Asset Retirement Obligation Disclosure [Abstract]

ASSET RETIREMENT OBLIGATIONS

ASSET RETIREMENT OBLIGATIONS

We have recorded AROs primarily for asbestos abatement at certain generation and substation facilities; the removal and dismantlement of a biomass generation facility; the dismantling of wind and solar generation projects; and the closure of CCR landfills at our generation facilities. We establish regulatory assets and liabilities to record the differences between ongoing expense recognition under the ARO accounting rules and the ratemaking practices for retirement costs authorized by the PSCW.

On our balance sheets, AROs are recorded within other long-term liabilities. The following table shows changes to our AROs during the years ended December 31:

(in millions)	2023			2022		2021
Balance as of January 1	$	71.7		$	70.8	$	54.5
Accretion	1.8			1.8		1.7
Additions	4.4		(1)	—		—
Revisions to estimated cash flows	(4.5)		(2)	0.3		17.3		(3)
Liabilities settled	(0.3)			(1.2)		(2.7)
Balance as of December 31	$	73.1		$	71.7	$	70.8

(1)    AROs increased primarily as a result of AROs being recorded for the legal requirement to dismantle, at retirement, the Badger Hollow II solar generation project.

(2)    AROs decreased primarily due to revisions made to removal estimates for fly ash landfills and changes in settlement timing of electric substation asbestos liabilities.

(3)     AROs increased primarily due to revisions made to removal estimates for Blue Sky, Glacier Hills, and Montfort.

XML

Common Equity

12 Months Ended

Dec. 31, 2023

Stockholders' Equity Note [Abstract]

COMMON EQUITY

COMMON EQUITY

Stock-Based Compensation

The following table summarizes our pre-tax stock-based compensation expense, including amounts allocated from WBS, and the related tax benefit recognized in income for the years ended December 31:

(in millions)	2023			2022		2021
Stock options	$	1.9		$	2.4	$	2.3
Restricted stock	2.3			2.3		2.2
Performance units	(0.9)		(1)	8.5		1.7
Stock-based compensation expense	$	3.3		$	13.2	$	6.2
Related tax benefit	$	0.9		$	3.6	$	1.7

(1)    The reduction in expense was due to a decrease in the fair value of the outstanding performance units.

Stock-based compensation costs capitalized during 2023, 2022, and 2021 were not significant.

Stock Options

The following is a summary of our employees' WEC Energy Group stock option activity during 2023:

Stock Options	Number of Options	Weighted-Average Exercise Price		Weighted-Average Remaining Contractual Life (in years)	Aggregate Intrinsic Value (in millions)
Outstanding as of January 1, 2023	475,509	$	70.63
Granted	30,495	93.69
Exercised	(57,704)	43.70
Outstanding as of December 31, 2023	448,300	75.67		5.1	$	5.6
Exercisable as of December 31, 2023	332,592	69.45		4.2	$	5.6

The aggregate intrinsic value of outstanding and exercisable options in the above table represents the total pre-tax intrinsic value that would have been received by the option holders had they exercised all of their options on December 31, 2023. This is calculated as the difference between WEC Energy Group's closing stock price on December 31, 2023, and the option exercise price, multiplied by the number of in-the-money stock options. The intrinsic value of options exercised during the years ended December 31, 2023, 2022, and 2021 was $2.5 million, $6.1 million, and $2.9 million, respectively. Cash received by WEC Energy Group from exercises of its options by our employees was $2.5 million, $4.3 million, and $2.6 million during the years ended December 31, 2023, 2022, and 2021, respectively. The actual tax benefit from option exercises for the same years was approximately $0.7 million, $1.7 million, and $0.8 million, respectively.

As of December 31, 2023, we expected to recognize approximately $0.5 million of unrecognized compensation cost related to unvested and outstanding WEC Energy Group stock options over the next 1.6 years on a weighted-average basis.

During the first quarter of 2024, the Compensation Committee awarded 33,081 non-qualified WEC Energy Group stock options with an exercise price of $85.05 and a weighted-average grant date fair value of $16.20 per option to certain of our officers and other key employees under its normal schedule of awarding long-term incentive compensation.

Restricted Shares

The following is a summary of our employees' WEC Energy Group restricted stock activity during 2023:

Restricted Shares	Number of Shares	Weighted-Average Grant Date Fair Value
Outstanding and unvested as of January 1, 2023	7,208	$	93.97
Granted	4,544	93.69
Released	(3,358)	93.21
Forfeited	(223)	94.13
Outstanding and unvested as of December 31, 2023	8,171	94.12

The intrinsic value of WEC Energy Group restricted stock held by our employees that was released was $0.3 million for the year ended December 31, 2023, and $0.4 million for each of the years ended December 31, 2022 and 2021. The actual tax benefit from released restricted shares was $0.1 million for each of the years ended December 31, 2023, 2022, and 2021.

As of December 31, 2023, we expected to recognize approximately $1.1 million of unrecognized compensation cost related to unvested and outstanding WEC Energy Group restricted stock over the next 1.7 years on a weighted-average basis.

During the first quarter of 2024, the Compensation Committee awarded 7,754 WEC Energy Group restricted shares to our officers and other key employees under its normal schedule of awarding long-term incentive compensation. The grant date fair value of these awards was $85.05 per share.

Performance Units

During 2023, 2022, and 2021, the Compensation Committee awarded 19,780; 21,158; and 18,138 WEC Energy Group performance units, respectively, to our officers and other key employees under the WEC Energy Group Performance Unit Plan.

Performance units with an intrinsic value of $1.2 million, $2.8 million, and $3.1 million were settled during 2023, 2022, and 2021, respectively. The actual tax benefit from the distribution of performance units for the same years was $0.3 million, $0.7 million, and $0.7 million, respectively.

At December 31, 2023, our employees held 53,116 WEC Energy Group performance units, including dividend equivalents. A liability of $1.3 million was recorded on our balance sheet at December 31, 2023 related to these outstanding units. As of December 31, 2023, we expected to recognize approximately $5.2 million of unrecognized compensation cost related to unvested and outstanding WEC Energy Group performance units over the next 1.9 years on a weighted-average basis.

During the first quarter of 2024, performance units held by our employees with an intrinsic value of $0.1 million were settled. The actual tax benefit from the distribution of these awards was not significant. In January 2024, the Compensation Committee also

awarded 25,242 WEC Energy Group performance units to our officers and other key employees under its normal schedule of awarding long-term incentive compensation.

Restrictions

Various financing arrangements and regulatory requirements impose certain restrictions on our ability to transfer funds to WEC Energy Group in the form of cash dividends, loans, or advances. In addition, Wisconsin law prohibits us from making loans to or guaranteeing obligations of WEC Energy Group or its subsidiaries.

In accordance with our most recent rate order, we may not pay common dividends above the test year forecasted amount reflected in our rate case, if it would cause our average common equity ratio, on a financial basis, to fall below our authorized level of 53.0%. A return of capital in excess of the test year amount can be paid by us at the end of the year provided that our average common equity ratio does not fall below the authorized level.

We may not pay common dividends to WEC Energy Group under our Restated Articles of Incorporation if any dividends on our outstanding preferred stock have not been paid. In addition, pursuant to the terms of our 3.60% Serial Preferred Stock, our ability to declare common dividends would be limited to 75% or 50% of net income during a 12-month period if our common stock equity to total capitalization, as defined in the preferred stock designation, is less than 25% and 20%, respectively.

See Note 13, Short-Term Debt and Lines of Credit, for a discussion of certain financial covenants related to our short-term debt obligations.

As of December 31, 2023, our retained earnings were fully restricted.

We do not believe that these restrictions will materially affect our operations or limit any dividend payments in the foreseeable future.

XML

Preferred Stock

12 Months Ended

Dec. 31, 2023

Class of Stock Disclosures [Abstract]

PREFERRED STOCK

PREFERRED STOCK

The following table shows preferred stock authorized and outstanding at December 31, 2023 and 2022:

(in millions, except share and per share amounts)	Shares Authorized	Shares Outstanding	Redemption Price Per Share		Total
$100 par value, Six Per Cent. Preferred Stock	45,000	44,498	$	—	$	4.4
$100 par value, Serial Preferred Stock 3.60% Series	2,286,500	260,000	101		26.0
$25 par value, Serial Preferred Stock	5,000,000	—	—		—
Total					$	30.4

XML

Short-Term Debt and Lines of Credit

12 Months Ended

Dec. 31, 2023

Short-Term Debt [Abstract]

SHORT-TERM DEBT AND LINES OF CREDIT

SHORT-TERM DEBT AND LINES OF CREDIT

The following table shows our short-term borrowings and their corresponding weighted-average interest rates as of December 31:

(in millions, except percentages)	2023			2022
Commercial paper
Amount outstanding at December 31	$	360.8		$	460.7
Average interest rate on amounts outstanding at December 31	5.48		%	4.59		%

Our average amount of commercial paper borrowings based on daily outstanding balances during 2023 was $109.9 million, with a weighted-average interest rate during the period of 5.19%.

We have entered into a bank back-up credit facility to maintain short-term credit liquidity which, among other terms, requires us to maintain, subject to certain exclusions, a total funded debt to capitalization ratio of 65% or less. As of December 31, 2023, we were in compliance with this ratio.

The information in the table below relates to our revolving credit facility used to support our commercial paper borrowing program, including remaining available capacity under this facility as of December 31:

(in millions)	Maturity	2023
Revolving credit facility	September 2026	$	500.0
Less:
Letters of credit issued inside credit facility		1.0
Commercial paper outstanding		360.8
Available capacity under existing agreement		$	138.2

This facility has a renewal provision for two extensions, subject to lender approval. Each extension is for a period of one year.

Our bank back-up credit facility contains customary covenants, including certain limitations on our ability to sell assets. The credit facility also contains customary events of default, including payment defaults, material inaccuracy of representations and warranties, covenant defaults, bankruptcy proceedings, certain judgments, Employee Retirement Income Security Act of 1974 defaults and change of control.

XML

Long-Term Debt

12 Months Ended

Dec. 31, 2023

Debt Disclosure [Abstract]

LONG-TERM DEBT

LONG-TERM DEBT

The following table is a summary of our long-term debt outstanding as of December 31:

(in millions)	Interest Rate	Year Due	2023		2022
WE Debentures (unsecured)	2.05%	2024	$	300.0	$	300.0
	3.10%	2025	250.0		250.0
	6.50%	2028	150.0		150.0
	1.70%	2028	300.0		300.0
	4.75%	2032	500.0		500.0
	5.625%	2033	335.0		335.0
	5.70%	2036	300.0		300.0
	3.65%	2042	250.0		250.0
	4.25%	2044	250.0		250.0
	4.30%	2045	250.0		250.0
	4.30%	2048	300.0		300.0
	6.875%	2095	100.0		100.0
WEPCo Environmental Trust (secured, nonrecourse) (1) (2)	1.578%	2024-2035	97.0		105.9
Total			3,382.0		3,390.9
Unamortized debt issuance costs			(13.0)		(14.9)
Unamortized discount, net			(14.6)		(15.6)
Total long-term debt, including current portion			3,354.4		3,360.4
Current portion of long-term debt			(309.0)		(8.9)
Total long-term debt			$	3,045.4	$	3,351.5

(1)    WEPCo Environmental Trust’s ETBs are secured by a pledge of and lien on environmental control property, which includes the right to impose, collect and receive a non-bypassable environmental control charge paid by all of our retail electric distribution customers, the right to obtain true-up adjustments of the environmental control charge, and all revenues or other proceeds arising from those rights and interests. See Note 21, Variable Interest Entities, for more information.

(2)    The long-term debt of WEPCo Environmental Trust requires periodic principal payments.

We amortize debt premiums, discounts, and debt issuance costs over the life of the debt using the straight-line method and we include the costs in interest expense.

The following table shows the future maturities of our long-term debt outstanding as of December 31, 2023:

(in millions)
2024	$	309.0
2025	259.2
2026	9.3
2027	9.5
2028	459.6
Thereafter	2,335.4
Total	$	3,382.0

Our long-term debt obligations contain covenants related to payment of principal and interest when due and various other obligations. Failure to comply with these covenants could result in an event of default, which could result in the acceleration of outstanding debt obligations.

XML

Leases

12 Months Ended

Dec. 31, 2023

Leases [Abstract]

LEASES

LEASES

Obligations Under Operating Leases

We have recorded right of use assets and lease liabilities associated with the following operating leases:

•Land we are leasing related to our Rothschild biomass plant through June 2051.

•Rail cars we are leasing to transport coal to various generating facilities through June 2027.

•Land we are leasing related to our utility solar generation projects through April 2073.

The operating leases generally require us to pay property taxes, insurance premiums, and operating and maintenance costs associated with the leased property. Certain of our leases contain options for early termination or to renew past the initial term, as set forth in the lease agreements. These options are included in our calculation of the lease obligations if it is reasonably certain that they will be exercised.

Obligations Under Finance Leases

In accordance with ASC Subtopic 980-842, Regulated Operations – Leases (Subtopic 980-842), the timing of expense recognition associated with our finance leases is modified to conform to the rate treatment. Amortization of the right-of-use asset is modified so that the total of the imputed interest and amortization costs equals the lease expense that is allowed for rate-making purposes. The difference between this lease expense and the sum of imputed interest and unadjusted amortization costs calculated under Topic 842 is deferred as a regulatory asset on our balance sheets in accordance with Subtopic 980-842.

Power Purchase Commitment

In 1997, we entered into a 25-year PPA with LSP-Whitewater Limited Partnership. The contract, for 236.5 MWs of firm capacity from a natural gas-fired cogeneration facility, included zero minimum energy requirements. The PPA expired on May 31, 2022; however, in November 2021, we entered into a tolling agreement with LSP-Whitewater Limited Partnership that commenced on June 1, 2022. Concurrent with the execution of the tolling agreement, we entered into an asset purchase agreement to acquire a 50% ownership interest in the natural gas-fired cogeneration facility, and the acquisition closed effective January 1, 2023. See Note 2, Acquisitions, for more information. Both the PPA and the tolling agreement were accounted for as a finance lease prior to the acquisition.

Port Washington Generating Station

We are leasing PWGS 1 and PWGS 2, two 545 MW natural gas-fired generation units, which were placed in service in July 2005 and May 2008, respectively, from We Power under PSCW approved leases. We are amortizing the leased units on a straight-line basis over the original 25-year term of the leases. The lease payments are expected to be recovered through our rates, as supported by Wisconsin's 2001 leased generation law.

The only variability associated with the PWGS lease payments relates to the potential for future changes in We Power's tax or interest rates, as the positive or negative impact of these changes is generally passed along to us, and subsequently to our

customers. Because variability in the lease payments is dependent upon a rate (interest rate or tax rate), the lease payments are considered unavoidable under Topic 842, and are included in the measurement of the right of use asset and lease liability.

When the PWGS 1 and PWGS 2 contracts expire in 2030 and 2033, respectively, we may, at our option and with proper notice, choose to renew one or both contracts for up to three consecutive renewal terms (each renewal term would approximate 80% of the then remaining economic useful life of the respective generation unit), purchase one or both generating facilities at fair market value, or allow the contracts to expire.

Elm Road Generating Station

We are leasing ER 1, ER 2, and the common facilities, which are also utilized by our OCPP generating units 5 through 8, from We Power under PSCW approved leases. We are amortizing the leased units on a straight-line basis over the 30-year term of the leases. ER 1 and ER 2 were placed in service in February 2010 and January 2011, respectively. The lease payments are expected to be recovered through our rates, as supported by Wisconsin's 2001 leased generation law.

The only variability associated with the ERGS lease payments relates to the potential for future changes in We Power's tax or interest rates, as the positive or negative impact of these changes are generally passed along to us, and subsequently to our customers. Because variability in the lease payments is dependent upon a rate (interest rate or tax rate), the lease payments are considered unavoidable under Topic 842, and are included in the measurement of the right of use asset and lease liability.

When the ER 1 and ER 2 contracts expire in 2040 and 2041, respectively, we may, at our option and with proper notice, choose to renew one or both contracts for up to three consecutive renewal terms (each renewal term would approximate 80% of the then remaining economic useful life of the respective generation unit), purchase one or both generating facilities at fair market value, or allow the contracts to expire.

Land Leases – Utility Solar Generation

We have entered into various land leases related to our investments in utility solar generation. Each lease has an initial term and one or more optional extensions. We expect the optional extensions to be exercised, and, as a result, all of the land leases are being amortized over an extended term of approximately 50 years. Once a solar project achieves commercial operation, the lease liability is remeasured to reflect the final total acres being leased. Our payments related to these leases are being recovered through rates.

Amounts Recognized in the Financial Statements and Other Information

The components of lease expense and supplemental cash flow information related to our leases for the years ended December 31 are as follows:

(in millions)	2023			2022			2021
Finance lease expense
Amortization of right of use assets (1)	$	77.5		$	74.2		$	68.1
Interest on lease liabilities (2)	329.5			334.3			341.2
Operating lease expense (3)	1.6			1.8			1.4
Total lease expense	$	408.6		$	410.3		$	410.7
Other information
Cash paid for amounts included in the measurement of lease liabilities
Operating cash flows for finance leases	$	329.5		$	334.3		$	341.2
Operating cash flows for operating leases	1.6			1.8			1.4
Financing cash flows for finance leases	77.0			73.6			67.5
Non-cash activities:
Right of use assets obtained in exchange for finance lease liabilities (4)	$	136.5		$	60.0		$	52.7
Right of use assets obtained in exchange for operating lease liabilities	2.3			—			0.3
Weighted-average remaining lease term – finance leases	16.2 years			16.5 years			16.9 years
Weighted-average remaining lease term – operating leases	24.9 years			27.0 years			28.5 years
Weighted-average discount rate – finance leases (5)	13.4		%	13.6		%	13.8		%
Weighted average discount rate – operating leases (5)	4.8		%	4.5		%	4.5		%

(1)    Amortization of right of use assets was included as a component of depreciation and amortization expense.

(2)    Interest on lease liabilities was included as a component of interest expense.

(3)    Operating lease expense was included as a component of other operation and maintenance expense.

(4)    Amounts are net of any reductions to right of use assets and finance lease liabilities resulting from remeasurements.

(5)    Because our operating leases and our power purchase commitment and solar land leases accounted for as finance leases do not provide an implicit rate of return, we used the fully collateralized incremental borrowing rates based upon information available for similarly rated companies in determining the present value of lease payments. For the PWGS and ERGS units that meet the definition of a finance lease, the rate implicit in the lease was readily determinable.

The following table summarizes our finance and operating lease right of use assets and obligations at December 31:

(in millions)	2023		2022		Balance Sheet Location
Right of use assets
Operating lease right of use assets, net	$	10.2	$	8.4	Other long-term assets
Finance lease right of use assets, net
Power purchase commitment (1)	$	—	$	38.3
PWGS	268.6		297.1
ERGS	1,362.0		1,335.8
Land leases – utility solar generation	92.4		67.9
Total finance lease right of use assets, net (2)	$	1,723.0	$	1,739.1	Property, plant, and equipment, net
Lease obligations
Current operating lease liabilities	$	0.8	$	0.6	Other current liabilities
Long-term operating lease liabilities	$	9.4	$	7.8	Other long-term liabilities
Current finance lease liabilities
Power purchase commitment (1)	$	—	$	36.3
PWGS	42.9		37.8
ERGS	44.9		38.2
Total current finance lease liabilities	$	87.8	$	112.3	Current portion of finance lease obligations
Long-term finance lease liabilities
PWGS	$	474.8	$	512.2
ERGS	2,177.8		2,118.8
Land leases – utility solar generation	99.6		71.3
Total long-term finance lease liabilities	$	2,752.2	$	2,702.3	Finance lease obligations

(1)    Effective January 1, 2023, we and WPS closed on the acquisition of Whitewater. See discussion above for more information.

(2)    Amounts are net of accumulated amortization of $1,483.8 million and $1,509.7 million at December 31, 2023 and 2022, respectively.

Future minimum lease payments under our operating and finance leases and the present value of our net minimum lease payments as of December 31, 2023, were as follows:

(in millions)	Total Operating Leases		PWGS		ERGS		Land Leases - Utility Solar Generation		Total Finance Leases
2024	$	1.3	$	102.8	$	314.0	$	3.4	$	420.2
2025	1.0		102.5		313.9		4.5		420.9
2026	1.0		102.4		313.9		4.6		420.9
2027	0.7		102.2		313.8		4.6		420.6
2028	0.5		102.2		313.7		4.7		420.6
Thereafter	13.9		302.0		3,614.2		347.5		4,263.7
Total minimum lease payments	18.4		814.1		5,183.5		369.3		6,366.9
Less: Interest	(8.2)		(296.4)		(2,960.8)		(269.7)		(3,526.9)
Present value of minimum lease payments	10.2		517.7		2,222.7		99.6		2,840.0
Less: Short-term lease liabilities	(0.8)		(42.9)		(44.9)		—		(87.8)
Long-term lease liabilities	$	9.4	$	474.8	$	2,177.8	$	99.6	$	2,752.2

As of February 22, 2024, we have not entered into any material leases that have not yet commenced.

XML

Income Taxes

12 Months Ended

Dec. 31, 2023

Income Tax Disclosure [Abstract]

INCOME TAXES

INCOME TAXES

Income Tax Expense

The following table is a summary of income tax expense for each of the years ended December 31:

(in millions)	2023		2022		2021
Current tax expense	$	122.0	$	81.0	$	90.3
Deferred income taxes, net	26.2		53.6		(30.7)
ITCs	(5.5)		(1.5)		(1.5)
Total income tax expense	$	142.7	$	133.1	$	58.1

Statutory Rate Reconciliation

The provision for income taxes for each of the years ended December 31 differs from the amount of income tax determined by applying the applicable United States statutory federal income tax rate to income before income taxes as a result of the following:

	2023				2022				2021
(in millions)	Amount		Effective Tax Rate		Amount		Effective Tax Rate		Amount		Effective Tax Rate
Statutory federal income tax	$	130.9	21.0	%	$	111.2	21.0	%	$	92.3	21.0	%
State income taxes net of federal tax benefit	37.4		6.0	%	33.1		6.3	%	28.2		6.4	%
Federal excess deferred tax amortization (1)	(20.8)		(3.3)	%	(23.2)		(4.4)	%	(23.2)		(5.3)	%
PTCs	(11.6)		(1.9)	%	(2.3)		(0.4)	%	(6.8)		(1.5)	%
AFUDC-Equity	(8.6)		(1.4)	%	(3.9)		(0.7)	%	(1.7)		(0.4)	%
Domestic production activities deferral	6.3		1.0	%	6.3		1.1	%	6.3		1.4	%
Federal excess deferred tax amortization – Wisconsin unprotected (2)	5.3		0.9	%	5.3		1.0	%	(42.7)		(9.7)	%
Other, net	3.8		0.6	%	6.6		1.2	%	5.7		1.3	%
Total income tax expense	$	142.7	22.9	%	$	133.1	25.1	%	$	58.1	13.2	%

(1)    The Tax Legislation required us to remeasure our deferred income taxes and we began to amortize the resulting excess protected deferred income taxes beginning in 2018 in accordance with normalization requirements. The decrease in income tax expense related to the amortization of the deferred tax benefits is offset by a decrease in revenue as the benefits are returned to customers, resulting in no impact on net income.

(2)    In accordance with the rate order received from the PSCW in December 2019, the majority of our net unprotected deferred tax benefits related to electric operations were amortized to reduce near-term impacts to our customers over a period of two years, beginning with 2020. Consistent with the same rate order, the net unprotected tax expense related to gas and steam operations continues to be amortized over a period of four years, which began in 2020. The increase (decrease) in income tax expense related to the amortization of the deferred taxes is offset by an increase (decrease) in revenue as amounts are either collected from or returned to customers, resulting in no impact on net income.

See Note 24, Regulatory Environment, for more information about the impact of the Tax Legislation and the Wisconsin rate order.

Deferred Income Tax Assets and Liabilities

The components of deferred income taxes as of December 31 were as follows:

(in millions)	2023		2022
Deferred tax assets
Tax gross up – regulatory items	$	103.4	$	110.3
Deferred revenues	103.9		106.5
Future tax benefits	7.1		10.1
Other	53.6		60.2
Total deferred tax assets	$	268.0	$	287.1
Deferred tax liabilities
Property-related	$	1,430.4	$	1,399.0
Deferred costs – plant retirements	186.2		198.0
Employee benefits and compensation	60.6		68.2
Deferred costs – SSR	37.5		40.9
Other	66.8		48.3
Total deferred tax liabilities	1,781.5		1,754.4
Deferred tax liability, net	$	1,513.5	$	1,467.3

Consistent with ratemaking treatment, deferred taxes in the table above are offset for temporary differences that have related regulatory assets and liabilities.

The components of net deferred tax assets associated with federal tax benefit carryforwards as of December 31, 2023 and 2022 are summarized in the tables below:

2023 (in millions)	Gross Value		Deferred Tax Effect		Earliest Year of Expiration
Future tax benefits as of December 31, 2023
Federal tax credit	$	—	$	7.1	2042
Balance as of December 31, 2023	$	—	$	7.1

2022 (in millions)	Gross Value		Deferred Tax Effect		Earliest Year of Expiration
Future tax benefits as of December 31, 2022
Federal tax credit	$	—	$	10.1	2041
Balance as of December 31, 2022	$	—	$	10.1

Unrecognized Tax Benefits

We had no unrecognized tax benefits at December 31, 2023 and 2022.

We do not expect any unrecognized tax benefits to affect our effective tax rate in periods after December 31, 2023.

For the years ended December 31, 2023, 2022, and 2021, we recognized no interest expense and no penalties related to unrecognized tax benefits in our income statements. At December 31, 2023 and 2022, we had no interest accrued and no penalties accrued related to unrecognized tax benefits on our balance sheets.

We do not anticipate any significant increases in the total amount of unrecognized tax benefits within the next 12 months.

Our primary tax jurisdictions include federal and the state of Wisconsin. With a few exceptions we are no longer subject to federal income tax examinations by the IRS for years prior to 2020. As of December 31, 2023, we were subject to examination by the Wisconsin taxing authority for tax years 2019 through 2023.

XML

Fair Value Measurements

12 Months Ended

Dec. 31, 2023

Fair Value Disclosures [Abstract]

FAIR VALUE MEASUREMENTS

FAIR VALUE MEASUREMENTS

The following tables summarize our financial assets and liabilities that were accounted for at fair value on a recurring basis, categorized by level within the fair value hierarchy:

	December 31, 2023
(in millions)	Level 1		Level 2		Level 3		Total
Derivative assets
Natural gas contracts	$	0.9	$	1.3	$	—	$	2.2
FTRs	—		—		2.5		2.5
Total derivative assets	$	0.9	$	1.3	$	2.5	$	4.7
Derivative liabilities
Natural gas contracts	$	16.1	$	3.1	$	—	$	19.2
Coal contracts	—		19.3		—		19.3
Total derivative liabilities	$	16.1	$	22.4	$	—	$	38.5

	December 31, 2022
(in millions)	Level 1		Level 2		Level 3		Total
Derivative assets
Natural gas contracts	$	1.6	$	2.5	$	—	$	4.1
FTRs	—		—		2.0		2.0
Coal contracts	—		32.7		—		32.7
Total derivative assets	$	1.6	$	35.2	$	2.0	$	38.8
Derivative liabilities
Natural gas contracts	$	29.3	$	0.7	$	—	$	30.0

The derivative assets and liabilities listed in the tables above include options, futures, physical commodity contracts, and other instruments used to manage market risks related to changes in commodity prices. They also include FTRs, which are used to manage electric transmission congestion costs in the MISO Energy Markets.

The following table summarizes the changes to derivatives classified as Level 3 in the fair value hierarchy at December 31:

(in millions)	2023		2022		2021
Balance at the beginning of the period	$	2.0	$	1.0	$	1.1
Purchases	8.1		7.6		3.1
Settlements	(7.6)		(6.6)		(3.2)
Balance at the end of the period	$	2.5	$	2.0	$	1.0

Fair Value of Financial Instruments

The following table shows the financial instruments included on our balance sheets that are not recorded at fair value:

	December 31, 2023				December 31, 2022
(in millions)	Carrying Amount		Fair Value		Carrying Amount		Fair Value
Preferred stock	$	30.4	$	21.4	$	30.4	$	22.7
Long-term debt, including current portion	3,354.4		3,255.4		3,360.4		3,143.2

The fair values of our long-term debt and preferred stock are categorized within Level 2 of the fair value hierarchy.

XML

Derivative Instruments

12 Months Ended

Dec. 31, 2023

Derivative Instruments and Hedging Activities Disclosure [Abstract]

DERIVATIVE INSTRUMENTS

DERIVATIVE INSTRUMENTS

Derivative assets and liabilities are included in the other current and other long-term line items on our balance sheets. The following table shows our derivative assets and derivative liabilities. None of the derivatives shown below were designated as hedging instruments.

	December 31, 2023				December 31, 2022
(in millions)	Derivative Assets		Derivative Liabilities		Derivative Assets		Derivative Liabilities
Current
Natural gas contracts	$	2.2	$	18.6	$	4.1	$	28.8
FTRs	2.5		—		2.0		—
Coal contracts	—		10.2		17.6		—
Total current	4.7		28.8		23.7		28.8
Long-term
Natural gas contracts	—		0.6		—		1.2
Coal contracts	—		9.1		15.1		—
Total long-term	—		9.7		15.1		1.2
Total	$	4.7	$	38.5	$	38.8	$	30.0

Realized gains and losses on derivatives are primarily recorded in cost of sales upon settlement; however, they may be subsequently deferred for future rate recovery or refund as the gains and losses are included in our fuel and natural gas cost recovery mechanisms. Our estimated notional sales volumes and realized gains and losses were as follows for the years ended:

	December 31, 2023			December 31, 2022			December 31, 2021
(in millions)	Volumes	Gains (Losses)		Volumes	Gains		Volumes	Gains
Natural gas contracts	68.5 Dth	$	(102.2)	59.7 Dth	$	86.6	69.2 Dth	$	50.8
FTRs	20.4 MWh	14.5		18.9 MWh	8.1		21.0 MWh	8.7
Total		$	(87.7)		$	94.7		$	59.5

At December 31, 2023 and 2022, we had posted cash collateral of $26.7 million and $46.7 million, respectively.

The following table shows derivative assets and derivative liabilities if derivative instruments by counterparty were presented net on our balance sheets:

	December 31, 2023					December 31, 2022
(in millions)	Derivative Assets		Derivative Liabilities			Derivative Assets		Derivative Liabilities
Gross amount recognized on the balance sheet	$	4.7	$	38.5		$	38.8	$	30.0
Gross amount not offset on the balance sheet	(1.3)		(16.5)		(1)	(1.8)		(29.5)		(2)
Net amount	$	3.4	$	22.0		$	37.0	$	0.5

(1)      Includes cash collateral posted of $15.2 million.

(2)      Includes cash collateral posted of $27.7 million.

XML

Employee Benefits

12 Months Ended

Dec. 31, 2023

Retirement Benefits [Abstract]

EMPLOYEE BENEFITS

EMPLOYEE BENEFITS

Pension and Other Postretirement Employee Benefits

We participate in WEC Energy Group's defined benefit pension plans and OPEB plans that cover substantially all of our employees. We are responsible for our share of the plan assets and obligations. The benefits for a portion of these plans are funded through irrevocable trusts, as allowed for income tax purposes. Our balance sheets reflect only the liabilities associated with our past and current employees and our share of the plan assets and obligations. We also offer medical, dental, and life insurance benefits to active employees and their dependents. We expense the costs of these benefits as incurred.

Generally, employees who started with us after 1995 receive a benefit based on a percentage of their annual salary plus an interest credit, while employees who started before 1996 receive a benefit based upon years of service and final average salary.

Management employees hired after December 31, 2014, and certain new represented employees hired after May 1, 2017, receive an annual company contribution to their 401(k) savings plan instead of being enrolled in the defined benefit plans.

We use a year-end measurement date to measure the funded status of all of the pension and OPEB plans. Due to the regulated nature of our business, we have concluded that substantially all of the unrecognized costs resulting from the recognition of the funded status of the pension and OPEB plans qualify as a regulatory asset.

The following tables provide a reconciliation of the changes in our share of the plans' benefit obligations and fair value of assets:

	Pension Benefits				OPEB Benefits
(in millions)	2023		2022		2023		2022
Change in benefit obligation
Obligation at January 1	$	894.9	$	1,144.0	$	144.6	$	190.6
Service cost	10.3		13.4		2.6		3.9
Interest cost	47.1		32.6		7.7		5.6
Participant contributions	—		—		5.6		6.6
Net transfer from/to affiliates	(1.2)		4.7		(0.4)		—
Actuarial (gain) loss	29.1		(211.3)		19.5		(46.9)
Benefit payments	(79.4)		(88.5)		(18.7)		(19.0)
Federal subsidy on benefits paid	N/A		N/A		1.3		1.2
Transfer	—		—		1.2		2.6
Obligation at December 31	$	900.8	$	894.9	$	163.4	$	144.6
Change in fair value of plan assets
Fair value at January 1	$	940.7	$	1,136.9	$	211.3	$	255.7
Actual return on plan assets	68.9		(115.8)		17.7		(32.6)
Employer contributions net of plan transfer (1)	3.2		3.8		(42.9)		0.1
Participant contributions	—		—		5.6		6.6
Net transfer from/to affiliates	(1.2)		4.3		(0.2)		0.5
Benefit payments	(79.4)		(88.5)		(18.7)		(19.0)
Fair value at December 31	$	932.2	$	940.7	$	172.8	$	211.3
Funded status at December 31	$	31.4	$	45.8	$	9.4	$	66.7

(1)    Employer contribution includes a $43.0 million transfer out of the WEC Energy Group Retiree Welfare Plan, in 2023, associated with the overfunded position of this plan.

In 2023, we had actuarial losses related to our pension benefit obligations of $29.1 million and actuarial gains in 2022 of $211.3 million. The primary driver for the actuarial loss was the change in discount rate. Partially offsetting the loss in 2023, was higher than expected asset returns. The discount rate for our pension benefits was 5.20%, 5.50%, and 2.94% in 2023, 2022, and 2021, respectively.

In 2023, we had actuarial losses related to our OPEB benefit obligation of $19.5 million and actuarial gains in 2022 of $46.9 million. The primary driver for the actuarial loss was changes to medical trend assumptions and a lower discount rate in 2023. Partially offsetting the loss in 2023, was higher than expected asset returns. The discount rate for our OPEB benefits was 5.15%, 5.50%, and 2.95% in 2023, 2022, and 2021, respectively.

The amounts recognized on our balance sheets at December 31 related to the funded status of the benefit plans were as follows:

	Pension Benefits				OPEB Benefits
(in millions)	2023		2022		2023		2022
Pension and OPEB assets	$	61.6	$	76.6	$	9.4	$	66.7
Other long-term liabilities	30.2		30.8		—		—
Total net assets	$	31.4	$	45.8	$	9.4	$	66.7

The accumulated benefit obligation for all defined benefit pension plans was $900.0 million and $894.0 million as of December 31, 2023 and 2022, respectively.

The following table shows information for the pension plans with an accumulated benefit obligation in excess of plan assets. There were no plan assets related to these pension plans. Amounts presented are as of December 31:

(in millions)	2023		2022
Accumulated benefit obligation	$	30.0	$	30.6

The following table shows information for pension plans with a projected benefit obligation in excess of plan assets. There were no plan assets related to these pension plans. Amounts presented are as of December 31:

(in millions)	2023		2022
Projected benefit obligation	$	30.2	$	30.8

We do not have any OPEB plans with an accumulated benefit obligation in excess of plan assets.

The following table shows the amounts that had not yet been recognized in our net periodic benefit cost as of December 31:

	Pension Benefits				OPEB Benefits
(in millions)	2023		2022		2023		2022
Net regulatory assets (liabilities)
Net actuarial loss (gain)	$	342.1	$	326.7	$	(89.1)	$	(113.0)
Prior service credits	(1.9)		(2.0)		(0.4)		(1.3)
Total	$	340.2	$	324.7	$	(89.5)	$	(114.3)

The components of net periodic benefit cost (credit) (including amounts capitalized to our balance sheets) for the years ended December 31 were as follows:

	Pension Benefits						OPEB Benefits
(in millions)	2023		2022		2021		2023		2022		2021
Service cost	$	10.3	$	13.4	$	14.4	$	2.6	$	3.9	$	4.3
Interest cost	47.1		32.6		31.1		7.7		5.6		5.3
Expected return on plan assets	(64.3)		(71.4)		(70.3)		(13.4)		(17.7)		(16.9)
Amortization of prior service credit	(0.1)		(0.1)		(0.1)		(0.9)		(1.3)		(1.2)
Amortization of net actuarial loss (gain)	9.2		29.8		41.9		(8.7)		(12.1)		(10.9)
Net periodic benefit cost (credit)	$	2.2	$	4.3	$	17.0	$	(12.7)	$	(21.6)	$	(19.4)

Effective January 1, 2023, the PSCW approved escrow accounting for pension and OPEB costs. As a result, as of December 31, 2023, we recorded a $1.2 million regulatory liability for pension costs and a $5.3 million regulatory asset for OPEB costs. The above table does not reflect any adjustments for the creation of these regulatory assets and liabilities.

The weighted-average assumptions used to determine the benefit obligations for the plans were as follows for the years ended December 31:

	Pension Benefits		OPEB Benefits
	2023	2022	2023	2022
Discount rate	5.20%	5.50%	5.15%	5.50%
Rate of compensation increase	4.00%	4.00%	N/A	N/A
Interest credit rate	5.14%	5.14%	N/A	N/A
Assumed medical cost trend rate (Pre 65)	N/A	N/A	6.25%	6.50%
Ultimate trend rate (Pre 65)	N/A	N/A	5.00%	5.00%
Year ultimate trend rate is reached (Pre 65)	N/A	N/A	2031	2031
Assumed medical cost trend rate (Post 65)	N/A	N/A	6.55%	6.00%
Ultimate trend rate (Post 65)	N/A	N/A	5.00%	5.00%
Year ultimate trend rate is reached (Post 65)	N/A	N/A	2030	2031

The weighted-average assumptions used to determine the net periodic benefit cost for the plans were as follows for the years ended December 31:

	Pension Benefits
	2023	2022	2021
Discount rate	5.50%	2.94%	2.63%
Expected return on plan assets	6.50%	6.75%	6.75%
Rate of compensation increase	4.00%	4.00%	4.00%
Interest credit rate	5.14%	5.16%	5.16%

	OPEB Benefits
	2023	2022	2021
Discount rate	5.50%	2.95%	2.65%
Expected return on plan assets	6.50%	7.00%	7.00%
Assumed medical cost trend rate (Pre 65)	6.50%	5.70%	5.85%
Ultimate trend rate (Pre 65)	5.00%	5.00%	5.00%
Year ultimate trend rate is reached (Pre 65)	2031	2028	2028
Assumed medical cost trend rate (Post 65)	6.00%	5.72%	5.86%
Ultimate trend rate (Post 65)	5.00%	5.00%	5.00%
Year ultimate trend rate is reached (Post 65)	2031	2028	2028

WEC Energy Group consults with its investment advisors on an annual basis to help forecast expected long-term returns on plan assets by reviewing historical returns as well as calculating expected total trust returns using the weighted-average of long-term market returns for each of the major target asset categories utilized in the trust. For 2024, the expected return on asset assumption for the pension plan and OPEB plans is 6.50%.

Plan Assets

Current pension trust assets and amounts which are expected to be contributed to the trusts in the future are expected to be adequate to meet pension payment obligations to current and future retirees.

The Investment Trust Policy Committee oversees investment matters related to all of our funded benefit plans. The Committee works with external actuaries and investment consultants on an on-going basis to establish and monitor investment strategies and target asset allocations. Forecasted cash flows for plan liabilities are regularly updated based on annual valuation results. Target allocations are determined utilizing projected benefit payment cash flows and risk analyses of appropriate investments. They are intended to reduce risk, provide long-term financial stability for the plans and maintain funded levels which meet long-term plan obligations while preserving sufficient liquidity for near-term benefit payments.

Our pension trust target asset allocations are 25% equity investments, 55% fixed income investments, and 20% private equity and real estate investments. The OPEB trust target asset allocations are 45% equity investments, 45% fixed income investments, and 10% real estate investments. Equity securities include investments in large-cap, mid-cap, and small-cap companies. Fixed income securities include corporate bonds of companies from diversified industries, mortgage and other asset backed securities, commercial paper, and United States Treasuries.

Pension and OPEB plan investments are recorded at fair value. See Note 1(o), Fair Value Measurements, for more information regarding the fair value hierarchy and the classification of fair value measurements based on the types of inputs used.

The following tables provide the fair values of our investments by asset class:

	December 31, 2023
	Pension Plan Assets								OPEB Assets
(in millions)	Level 1		Level 2		Level 3		Total		Level 1		Level 2		Level 3		Total
Asset Class
Equity securities:
United States equity	$	57.4	$	—	$	—	$	57.4	$	17.3	$	—	$	—	$	17.3
International equity	51.4		—		—		51.4		16.3		—		—		16.3
Fixed income securities: (1)
United States bonds	—		404.1		—		404.1		13.4		52.4		—		65.8
International bonds	—		31.7		—		31.7		—		3.3		—		3.3
	$	108.8	$	435.8	$	—	$	544.6	$	47.0	$	55.7	$	—	$	102.7
Investments measured at net asset value:
Equity securities							137.9								34.4
Fixed income securities							0.1								6.3
Other							249.6								29.4
Total							$	932.2							$	172.8

(1)    This category represents investment grade bonds of United States and foreign issuers denominated in United States dollars from diverse industries.

	December 31, 2022
	Pension Plan Assets								OPEB Assets
(in millions)	Level 1		Level 2		Level 3		Total		Level 1		Level 2		Level 3		Total
Asset Class
Equity securities:
United States equity	$	69.5	$	—	$	—	$	69.5	$	23.6	$	—	$	—	$	23.6
International equity	60.8		—		—		60.8		20.2		—		—		20.2
Fixed income securities: (1)
United States bonds	—		419.2		—		419.2		25.8		45.8		—		71.6
International bonds	—		35.5		—		35.5		—		3.9		—		3.9
	$	130.3	$	454.7	$	—	$	585.0	$	69.6	$	49.7	$	—	$	119.3
Investments measured at net asset value:
Equity securities							139.7								47.3
Fixed income securities							—								12.7
Other							216.0								32.0
Total							$	940.7							$	211.3

(1)    This category represents investment grade bonds of United States and foreign issuers denominated in United States dollars from diverse industries.

Cash Flows

We expect to contribute $3.2 million to the pension plans and $0.2 million to the OPEB plans in 2024, dependent upon various factors affecting us, including our liquidity position and possible tax law changes.

The following table shows the payments, reflecting expected future service, that we expect to make for pension and OPEB over the next 10 years:

(in millions)	Pension Benefits		OPEB Benefits
2024	$	86.9	$	11.5
2025	80.3		11.3
2026	79.6		11.3
2027	76.0		11.5
2028	73.4		11.6
2029-2033	331.3		58.9

Savings Plans

WEC Energy Group sponsors 401(k) savings plans that allow substantially all of our full-time employees to contribute a portion of their pre-tax and/or after-tax income in accordance with plan-specified guidelines. A percentage of employee contributions are matched by us through a contribution into the employee's savings plan account, up to certain limits. The 401(k) savings plans include an Employee Stock Ownership Plan. Certain employees receive an employer retirement contribution, which amounts are contributed to an employee's savings plan account based on the employee's wages. Total costs incurred under all of these plans were $15.5 million, $14.2 million, and $12.3 million in 2023, 2022, and 2021, respectively.

XML

Segment Information

12 Months Ended

Dec. 31, 2023

Segment Reporting [Abstract]

SEGMENT INFORMATION

SEGMENT INFORMATION

We use net income attributed to common shareholder to measure segment profitability and to allocate resources to our business. At December 31, 2023, we reported two segments, our utility segment and our other segment, which are described below.

Our utility segment includes our electric utility operations, including steam operations, and our natural gas utility operations.

•Our electric utility operations are engaged in the generation, distribution, and sale of electricity to customers in southeastern Wisconsin (including metropolitan Milwaukee), east central Wisconsin, and northern Wisconsin. In addition, our steam operations produce, distribute, and sell steam to customers in metropolitan Milwaukee.

•Our natural gas utility operations are engaged in the purchase, distribution, and sale of natural gas to retail customers as well as the transportation of customer-owned natural gas in southeastern, east central, and northern Wisconsin.

No significant items were reported in the other segment during the twelve months ended December 31, 2023, 2022, and 2021.

All of our operations and assets are located within the United States.

XML

Variable Interest Entities

12 Months Ended

Dec. 31, 2023

Organization, Consolidation and Presentation of Financial Statements [Abstract]

VARIABLE INTEREST ENTITIES

VARIABLE INTEREST ENTITIES

The primary beneficiary of a VIE must consolidate the entity's assets and liabilities. In addition, certain disclosures are required for significant interest holders in VIEs.

We assess our relationships with potential VIEs, such as our coal suppliers, natural gas suppliers, coal transporters, natural gas transporters, and other counterparties related to PPAs, investments, and joint ventures. In making this assessment, we consider, along with other factors, the potential that our contracts or other arrangements provide subordinated financial support, the obligation to absorb the entity's losses, the right to receive residual returns of the entity, and the power to direct the activities that most significantly impact the entity's economic performance.

WEPCo Environmental Trust Finance I, LLC

In November 2020, the PSCW issued a financing order approving the securitization of $100 million of undepreciated environmental control costs related to our retired Pleasant Prairie power plant, the carrying costs accrued on the $100 million during the securitization process, and the related financing fees. The financing order also authorized us to form WEPCo Environmental Trust, a bankruptcy-remote special purpose entity, for the sole purpose of issuing ETBs to recover the costs approved in the financing order. WEPCo Environmental Trust is our wholly owned subsidiary.

In May 2021, WEPCo Environmental Trust issued ETBs and used the proceeds to acquire environmental control property from us. The environmental control property is recorded as a regulatory asset on our balance sheets and includes the right to impose, collect, and receive a non-bypassable environmental control charge from our retail electric distribution customers until the ETBs are paid in full and all financing costs have been recovered. The ETBs are secured by the environmental control property. Cash collections from the environmental control charge and funds on deposit in trust accounts are the sole sources of funds to satisfy the debt obligation. The bondholders do not have any recourse to us or any of our affiliates.

We act as the servicer of the environmental control property on behalf of WEPCo Environmental Trust and are responsible for metering, calculating, billing, and collecting the environmental control charge. As necessary, we are authorized to implement periodic adjustments of the environmental control charge. The adjustments are designed to ensure the timely payment of principal, interest, and other ongoing financing costs. We remit all collections of the environmental control charge to WEPCo Environmental Trust's indenture trustee.

WEPCo Environmental Trust is a VIE primarily because its equity capitalization is insufficient to support its operations. As described above, we have the power to direct the activities that most significantly impact WEPCo Environmental Trust's economic performance. Therefore, we are considered the primary beneficiary of WEPCo Environmental Trust, and consolidation is required.

The following table summarizes the impact of WEPCo Environmental Trust on our balance sheet:

(in millions)	December 31, 2023		December 31, 2022
Assets
Other current assets (restricted cash)	$	0.8	$	3.0
Regulatory assets	85.9		92.4
Other long-term assets (restricted cash)	0.6		0.6
Liabilities
Current portion of long-term debt	9.0		8.9
Other current liabilities (accrued interest)	0.1		0.1
Long-term debt	85.3		94.1

Power Purchase Commitment

On May 31, 2022, our PPA with LSP-Whitewater Limited Partnership that represented a variable interest expired. This agreement was for 236.5 MWs of firm capacity from a natural gas-fired cogeneration facility, and we accounted for it as a finance lease.

In November 2021, we entered into a tolling agreement with LSP-Whitewater Limited Partnership that commenced on June 1, 2022, upon the expiration of the PPA. Concurrent with the execution of the tolling agreement, we, along with WPS, entered into an agreement to purchase the natural gas-fired cogeneration facility. This asset purchase agreement was approved by the PSCW in December 2022, and the acquisition closed effective January 1, 2023. In accordance with the purchase agreement, we acquired a 50% ownership interest. See Note 2, Acquisitions, for more information on the acquisition of this facility. The tolling agreement represented a variable interest until the facility was acquired since its terms were substantially similar to the terms of the PPA. Based on the risks of the entity, including operations, maintenance, dispatch, financing, fuel costs, and other factors, we were not the primary beneficiary of the entity. We did not hold an equity or debt interest in the entity, and there was no residual guarantee associated with the tolling agreement. Similar to the PPA, we accounted for the tolling agreement as a finance lease.

XML

Commitments and Contingencies

12 Months Ended

Dec. 31, 2023

Commitments and Contingencies Disclosure [Abstract]

COMMITMENTS AND CONTINGENCIES

COMMITMENTS AND CONTINGENCIES

We have significant commitments and contingencies arising from our operations, including those related to unconditional purchase obligations, environmental matters, and enforcement and litigation matters.

Unconditional Purchase Obligations

We have obligations to distribute and sell electricity and natural gas to our customers and expect to recover costs related to these obligations in future customer rates. In order to meet these obligations, we routinely enter into long-term purchase and sale commitments for various quantities and lengths of time.

The following table shows our minimum future commitments related to these purchase obligations as of December 31, 2023:

				Payments Due By Period
(in millions)	Date Contracts Extend Through	Total Amounts Committed		2024		2025		2026		2027		2028		Later Years
Electric utility:
Nuclear	2033	$	6,280.6	$	600.3	$	634.5	$	681.6	$	730.4	$	782.6	$	2,851.2
Coal supply and transportation	2026	354.9		247.9		94.2		12.8		—		—		—
Purchased power	2051	29.2		3.6		2.3		2.4		2.4		2.5		16.0
Natural gas utility supply and transportation	2048	460.8		68.2		39.9		33.2		28.6		25.1		265.8
Total		$	7,125.5	$	920.0	$	770.9	$	730.0	$	761.4	$	810.2	$	3,133.0

Environmental Matters

Consistent with other companies in the energy industry, we face significant ongoing environmental compliance and remediation obligations related to current and past operations. Specific environmental issues affecting us include, but are not limited to, current and future regulation of air emissions such as SO2, NOx, fine particulates, mercury, and GHGs; water intake and discharges; management of coal combustion products such as fly ash; and remediation of impacted properties, including former manufactured gas plant sites.

We have continued to pursue a proactive strategy to manage our environmental compliance obligations, including:

•the development of additional sources of renewable electric energy supply, battery storage, and natural gas and LNG storage facilities;

•the addition of improvements for water quality matters such as treatment technologies to meet regulatory discharge limits and improvements to our cooling water intake systems;

•the addition of emission control equipment to existing facilities to comply with ambient air quality standards and federal clean air rules;

•the protection of wetlands and waterways, biodiversity including threatened and endangered species, and cultural resources associated with utility construction projects;

•the retirement of older coal-fired power plants and conversion to modern, efficient, natural gas generation, super-critical pulverized coal generation, and/or replacement with renewable generation;

•the beneficial use of ash and other products from coal-fired and biomass generating units;

•the remediation of former manufactured gas plant sites;

•the reduction of methane emissions across our natural gas distribution system by upgrading infrastructure; and

•the reporting of GHG emissions to comply with federal clean air rules.

Air Quality

Cross State Air Pollution Rule – Good Neighbor Plan

In March 2023, the EPA issued its final Good Neighbor Plan, which became effective in August 2023 and requires significant reductions in ozone-forming emissions of NOx from power plants and industrial facilities. After review of the final rule, we believe that we are well positioned to meet the requirements.

Our RICE units in Wisconsin are not currently subject to the final rule as each unit is less than 25 MWs. To the extent we use RICE engines for natural gas distribution operations, those engines not part of an LDC are subject to the emission limits and operational requirements of the rule beginning in 2026. The EPA has exempted LDCs from the final rule.

Mercury and Air Toxics Standards

In 2012, the EPA issued the MATS to limit emissions of mercury, acid gases, and other hazardous air pollutants. In April 2023, the EPA issued the pre-publication version of a proposed rule to strengthen and update MATS to reflect recent developments in control technologies and performance of coal and oil-fired units. The EPA proposed three revisions including a proposal to lower the PM

limit from 0.03 lb/MMBtu to 0.01 lb/MMBtu. The EPA also sought comments on an even lower limit of 0.006 lb/MMBtu. Adoption of either of these lower limits could have an adverse effect on our operations.

National Ambient Air Quality Standards

Ozone

After completing its review of the 2008 ozone standard, the EPA released a final rule in October 2015, creating a more stringent standard than the 2008 NAAQS. The 2015 ozone standard lowered the 8-hour limit for ground-level ozone. In November 2022, the EPA's 2022 CASAC Ozone Review Panel issued a draft report supporting the reconsideration of the 2015 standard. The EPA staff initially issued a draft Policy Assessment in March 2023 that supported the reconsideration, however, in August 2023 it announced that it is instead restarting its ozone standard evaluation. The EPA has indicated it plans to release its Integrated Review Plan in fall 2024. This new review is anticipated to take 3 to 5 years to complete.

In February 2022, revisions to the Wisconsin Administrative Code to adopt the 2015 standard were finalized. The amended regulations incorporated by reference the federal air pollution monitoring requirements related to the standard. The WDNR submitted the rule updates as a SIP revision to the EPA, which the EPA approved in February 2023.

In April 2022, the EPA proposed to find that the Milwaukee, Sheboygan, and Chicago, IL-IN-WI nonattainment areas did not meet the marginal attainment deadline of August 2021 and should be adjusted to "moderate" nonattainment status for the 2015 standard. In October 2022, the EPA published its final reclassifications from "marginal" to "moderate" for these areas, effective November 7, 2022. Accordingly, the WDNR submitted a SIP revision to the EPA in December 2022 to address the moderate nonattainment status.

In October 2023, the EPA found that 11 states, including Wisconsin, failed to submit timely SIP revisions to address nonattainment areas classified as "moderate" for the 2015 standard. This action triggered a 24-month deadline for states to get their SIP approved or the EPA will issue a federal implementation plan. Additionally, offset sanctions will take effect in 18 months if the SIP is not approved. The offset sanctions impact volatile organic compound and NOx emissions from new or modified sources in the nonattainment areas.

We believe that we are well positioned to meet the requirements associated with the 2015 ozone standard and do not expect to incur significant costs to comply with the associated state and federal rules.

Particulate Matter

In December 2020, the EPA completed its 5-year review of the 2012 annual and 24-hour standards for fine PM and determined that no revisions were necessary to the current annual standard of 12 µg/m3 or the 24-hour standard of 35 µg/m3. All counties within our service territory are in attainment with the current 2012 standards. Under the Biden Administration's policy review, the EPA concluded that the scientific evidence and information from the December 2020 determination supports revising the level of the annual standard for the PM NAAQS to below the current level of 12 µg/m3, while retaining the 24-hour standard. In January 2023, the EPA announced its proposed decision to revise the primary (health-based) annual PM2.5 standard from its current level of 12 µg/m3 to within the range of 9 to 10 µg/m3. The EPA also proposed not to change the current secondary (welfare-based) annual PM2.5 standard, primary and secondary 24-hour PM2.5 standards, and primary and secondary PM10 standards. The EPA did, however, take comments on the full range (between 8 and 11 µg/m3) included in the CASAC's latest report. The EPA finalized the rule on February 7, 2024 and lowered the primary annual PM2.5 level to 9 µg/m3, which could cause some nonattainment areas that may affect permitting at our facilities. The secondary and 24-hour standards remain unchanged. The EPA will designate areas as attainment and nonattainment with the new standard by early 2026. The WDNR will need to draft and submit a SIP for the EPA's approval.

Climate Change

In May 2023, the EPA proposed GHG performance standards for existing fossil-fired steam generating and gas combustion units and also proposed to repeal the Affordable Clean Energy rule, which had replaced the Clean Power Plan. For coal plants, no standards would apply under the proposed version of the rule until 2032, and after 2032 the applicable standard would depend on the unit's retirement date. For combined cycle natural gas plants above a 50% capacity factor, the proposed rule is highly dependent on the use of hydrogen as an alternative fuel, and on carbon capture technology. For simple cycle natural gas-fired combustion turbines, the proposed version of the rule does not include applicable limits as long as the capacity factor is less than 20%. The new Weston

RICE project is not affected under the rule because each RICE unit is less than 25 MWs. We continue to evaluate the proposed rule to understand the impacts to our operations. A final rule is expected in the second quarter of 2024.

In May 2023, the EPA proposed to revise the NSPS for GHG emissions from new, modified, and reconstructed fossil-fueled power plants. The EPA is proposing two distinct 111(b) rules – one for natural gas-fired stationary combustion turbines and the other for coal-fired units. New stationary combustion turbine units would be divided into three subcategories based on their annual capacity factor – low load, intermediate load, and base load. Our RICE units are not affected by this rule since each unit is below 25 MWs. WEC Energy Group's ESG Progress Plan is heavily focused on reducing GHG emissions. The EPA has indicated that it anticipates a final rule in the second quarter of 2024.

The EPA released proposed regulations for the Mandatory Greenhouse Gas Reporting Rule, 40 CFR Part 98, in June 2022. In May 2023, the EPA released a supplementary proposal, which includes updates of the global warming potentials to determine CO2 equivalency for threshold reporting and the addition of a new section regarding energy consumption. The proposed revisions could impact the reporting required for our electric generation facilities and LDC. In August 2023, the EPA also issued its proposed updates to amend reporting requirements for petroleum and natural gas systems, with an anticipated final rule to be issued in early 2024. We are currently evaluating the potential impact of the proposed rule, if any, on our operations.

WEC Energy Group's ESG Progress Plan includes the retirement of older, fossil-fueled generation, to be replaced with zero-carbon-emitting renewables and clean natural gas-fueled generation. We have already retired approximately 1,500 MWs of fossil-fueled generation since the beginning of 2018. WEC Energy Group expects to retire approximately 1,800 MWs of additional fossil-fueled generation by the end of 2031, which includes the planned retirements in 2024-2025 of OCPP Units 5-8. See Note 8, Property, Plant, and Equipment, for more information related to these planned power plant retirements. In May 2021, WEC Energy Group announced goals to achieve reductions in carbon emissions from its electric generation fleet by 60% by the end of 2025 and by 80% by the end of 2030, both from a 2005 baseline. WEC Energy Group expects to achieve these goals by continuing to make operating refinements, retiring less efficient generating units, and executing its capital plan. Over the longer term, the target for WEC Energy Group's generation fleet is to be net carbon neutral by 2050.

WEC Energy Group also continues to reduce methane emissions by improving its natural gas distribution systems, and has set a target across its natural gas distribution operations to achieve net-zero methane emissions by the end of 2030. WEC Energy Group plans to achieve its net-zero goal through an effort that includes both continuous operational improvements and equipment upgrades, as well as the use of RNG throughout its utility systems.

Water Quality

Clean Water Act Cooling Water Intake Structure Rule

The EPA issued a final regulation under Section 316(b) of the CWA that became effective in October 2014 and requires the location, design, construction, and capacity of cooling water intake structures at existing power plants reflect the BTA for minimizing adverse environmental impacts. The rule applies to all of our existing generating facilities with cooling water intake structures, except for the ERGS units, which were permitted and received a final BTA determination under the rules governing new facilities.

Pursuant to a WDNR rule, which became effective in June 2020, the requirements of federal Section 316(b) of the CWA were incorporated into the Wisconsin Administrative Code. The WDNR applies this rule when establishing BTA requirements for cooling water intake structures at existing facilities. These BTA requirements are incorporated into WPDES permits for our facilities.

We have received a final BTA determination for VAPP. We have received interim BTA determinations for OCPP Units 5-8. We believe that existing technology installed at the OCPP facility meets the BTA requirements; however, depending on the timing of the permit reissuance, all four generating units at the OCPP may be retired prior to the WDNR making a final BTA decision, anticipated in 2025.

The WDNR reissued the WPDES permit for PWGS effective October 2023. This reissued permit includes a conditional BTA determination with conditions for the existing PWGS porous dike (rock breakwater) cooling water intake structure. We do not anticipate compliance with these conditions will result in a material impact on our financial condition or the efficiency of power plant operations.

Steam Electric Effluent Limitation Guidelines

The EPA's ELG rule, effective January 2016 and modified in 2020, revised the treatment technology requirements related to BATW and wet FGD wastewaters at existing coal-fueled facilities and created new requirements for several types of power plant wastewaters. The two new requirements that affect us relate to discharge limits for BATW and wet FGD wastewater. Although our power plant facilities already have advanced wastewater treatment technologies installed that meet many of the discharge limits established by this rule, certain facility modifications are necessary to meet the ELG rule requirements. Through 2023, compliance costs associated with the ELG rule required $97 million in capital investment. An $8 million BATW modification to OCPP Units 7 and 8 was completed and placed in-service in mid-2021, and in December 2021, the PSCW issued a Certificate of Authority approving the $89 million ERGS FGD wastewater treatment system modification. The BATW modifications did not require PSCW approval prior to construction. All of these ELG required projects were placed in-service ahead of WPDES permit deadlines.

In March 2023, the EPA issued the proposed "supplemental ELG rule." The rule would replace the existing 2020 ELG rule and, as proposed, would establish stricter limitations on: 1) BATW; 2) FGD wastewater; 3) CCR leachate; and 4) legacy wastewaters. The most significant proposed ELG rule change is a ZLD requirement for FGD wastewater. Under the proposed rule, this new ZLD requirement must be met by a date determined by the WDNR that is as soon as possible beginning 60 days following publication of the final rule, but no later than December 31, 2029.

The proposed rule would also create a subcategory for "early adopters" that have already installed a compliant biological treatment system by the date of the proposed rule. Early adopters would not be required to install further FGD wastewater treatment, provided the facility owner also agrees to permanently cease combustion of coal by December 31, 2032. Although the $89 million biological treatment system at ERGS is complete and was placed in service in December 2023 to meet the WPDES permit deadline, the timing of the project's completion did not comply with the deadline proposed by the EPA to qualify for the early adopter status. In addition, we do not believe that the biological treatment system would be compliant with the additional ZLD FGD wastewater treatment requirements as proposed. In May 2023, we submitted written comments to the EPA articulating these concerns, including the cost impact to our customers. The EPA has indicated that it anticipates issuing the final rule in the second quarter of 2024.

If the supplemental ELG rule is finalized as proposed, we anticipate that our coal-fueled facilities, including ER 1 and ER 2 that were built with ELG-compliant dry BA transport systems, will meet the BATW rule provisions.

The EPA also proposed requirements for legacy wastewaters and landfill leachate. We have reviewed the proposed requirements to determine potential costs and actions required for our facilities. We submitted comments to the EPA regarding these proposed requirements.

Waters of the United States

In January 2023, the EPA and the Army Corps (the agencies) together released a final rule effective in March 2023 that established standards for identifying which wetland or surface drainage features qualify as WOTUS based on its pre-2015 definition. The pre-2015 approach involved applying factors established through case law and agency precedents to determine whether a wetland or surface drainage feature is subject to federal jurisdiction.

In May 2023, in Sackett v. EPA, the Supreme Court issued a decision significantly narrowing federal jurisdiction over wetlands to "traditional navigable waters" and wetlands or other waters that have a "continuous surface connection" with a traditional navigable water.

In August 2023, the agencies revised the final rule to conform the definition of WOTUS to the Supreme Court's May 2023 Sackett decision. The conforming rule became effective upon publication in the Federal Register on September 8, 2023.

We anticipate this final rule revision based on the Sackett decision may lead to a decreased number of projects that require Army Corps federal wetland permits. This decision also may affect the administration of some state programs. At this point, our projects requiring federal permits are moving ahead, but we are monitoring these recent developments to better understand potential future impacts.

Land Quality

Manufactured Gas Plant Remediation

We have identified sites at which we or a predecessor company owned or operated a manufactured gas plant or stored manufactured gas. We have also identified other sites that may have been impacted by historical manufactured gas plant activities. We are responsible for the environmental remediation of these sites. We are also working with the state of Wisconsin in our investigation and remediation planning. These sites are at various stages of investigation, monitoring, remediation, and closure.

The future costs for detailed site investigation, future remediation, and monitoring are dependent upon several variables including, among other things, the extent of remediation, changes in technology, and changes in regulation. Historically, our regulators have allowed us to recover incurred costs, net of insurance recoveries and recoveries from potentially responsible parties, associated with the remediation of manufactured gas plant sites. Accordingly, we have established regulatory assets for costs associated with these sites.

We have established the following regulatory assets and reserves for manufactured gas plant sites as of December 31:

(in millions)	2023		2022
Regulatory assets	$	12.2	$	14.6
Reserves for future environmental remediation (1)	$	10.3	$	10.3

(1)    Recorded within other long-term liabilities on our balance sheets.

Coal Combustion Residuals Rule

The EPA issued a pre-publication proposed rule for CCR in May 2023 that would apply to landfills, historic fill sites, and projects where CCR was placed at a power plant site. As proposed, the rule would regulate previously exempt closed landfills.

We are actively engaged with our trade organizations and provided them information to include in their comments to the EPA. The EPA has indicated that it anticipates issuing a final rule in the second quarter of 2024. As proposed, the rule could have a material adverse impact on our coal ash landfills and require additional remediation that has not been required under the current state programs.

Renewables, Efficiency, and Conservation

Wisconsin Legislation

In 2005, Wisconsin enacted Act 141, which established a goal that 10% of all electricity consumed in Wisconsin be generated by renewable resources annually. We have achieved our required renewable energy percentage of 8.27% by constructing various wind parks, a solar park, a biomass facility, and by also relying on renewable energy purchases. We continue to review our renewable energy portfolio and acquire cost-effective renewables as needed to meet our requirements on an ongoing basis. The PSCW administers the renewable program related to Act 141, and we fund the program, along with other utilities, based on 1.2% of our annual retail operating revenues.

Enforcement and Litigation Matters

We are involved in legal and administrative proceedings before various courts and agencies with respect to matters arising in the ordinary course of business. Although we are unable to predict the outcome of these matters, management believes that appropriate reserves have been established and that final settlement of these actions will not have a material impact on our financial condition or results of operations.

XML

Supplemental Cash Flow Information

12 Months Ended

Dec. 31, 2023

Additional Cash Flow Elements and Supplemental Cash Flow Information [Abstract]

SUPPLEMENTAL CASH FLOW INFORMATION

SUPPLEMENTAL CASH FLOW INFORMATION

Non-Cash Transactions

	Year Ended December 31
(in millions)	2023		2022		2021
Cash paid for interest, net of amount capitalized	$	463.8	$	449.2	$	460.8
Cash paid for income taxes, net (1)	99.1		88.0		88.0
Significant non-cash investing and financing transactions:
Accounts payable related to construction costs	71.8		89.1		42.4
Increase in receivables related to insurance proceeds	—		—		37.3
Liabilities accrued for software licensing agreement	—		3.1		—

(1)    Cash paid for income taxes in 2023 was net of $4.9 million of PTCs that were sold to a third party.

Restricted Cash

The statements of cash flows include our activity related to cash, cash equivalents, and restricted cash. The following table reconciles the cash, cash equivalents, and restricted cash amounts reported within the balance sheets at December 31 to the total of these amounts shown on the statements of cash flows:

(in millions)	2023		2022		2021
Cash and cash equivalents	$	6.1	$	6.1	$	—
Restricted cash included in other current assets	0.8		3.0		2.4
Restricted cash included in other long-term assets	0.6		38.6		0.6
Cash, cash equivalents, and restricted cash	$	7.5	$	47.7	$	3.0

Our restricted cash consisted of the following:

•Cash on deposit in a financial institution that is restricted to satisfy the requirements of a debt agreement at WEPCo Environmental Trust. See Note 21, Variable Interest Entities, for more information.

•Cash used during January 2023 to purchase a 50% interest in a natural gas-fired cogeneration facility located in Whitewater, Wisconsin. This cash was included in other long-term assets at December 31, 2022. See Note 2, Acquisitions, for more information on the purchase of this facility.

XML

Regulatory Environment

12 Months Ended

Dec. 31, 2023

Regulated Operations [Abstract]

REGULATORY ENVIRONMENT

REGULATORY ENVIRONMENT

2024 Limited Rate Case Re-Opener

In accordance with our rate order approved by the PSCW in December 2022, we filed a request with the PSCW in May 2023 for a limited electric and natural gas rate case re-opener. Our limited electric rate case re-opener included updated fuel costs and revenue requirements for the generation projects that were previously approved by the PSCW and were placed into service in 2023 or are expected to be placed into service in 2024. It also included the projected savings from the retirement of the OCPP Units 5 and 6, which are expected to be retired in May 2024. Our limited natural gas rate case re-opener reflected the additional revenue requirements associated with our previously approved LNG project that was placed into service in November 2023.

On December 20, 2023, the PSCW issued a final written order approving electric and natural gas rate increases, effective January 1, 2024. The final orders reflected the following:

2024 incremental rate increases
Electric (1)	$	82.2	million	/	2.5%
Gas	$	23.9	million	/	4.5%

(1)    Amount reflects the impact to our Wisconsin retail electric operations and includes the incremental increase from updated fuel costs.

Our ROE and common equity component average were not addressed in the limited rate case re-opener.

2023 and 2024 Rates

In April 2022, we filed a request with the PSCW to increase our retail electric, natural gas, and steam rates. Our request was updated in July 2022 to reflect new developments that impacted the original proposal. The requested increase in electric rates was driven by capital investments in new wind, solar, and battery storage; capital investments in natural gas generation; reliability investments, including grid hardening projects to bury power lines and strengthen our distribution system against severe weather; and changes in wholesale business with other utilities. Many of these investments had already been approved by the PSCW. The requested increase in natural gas rates primarily related to capital investments previously approved by the PSCW, including LNG storage for our natural gas distribution system.

In September 2022, we entered into a settlement agreement with certain intervenors to resolve most of the outstanding issues in our rate case; however, the PSCW declined to approve the settlement agreement. In December 2022, the PSCW issued a final written order approving electric, natural gas, and steam base rate increases, effective January 1, 2023. The final order reflected the following:

2023 base rate increase
Electric	$	283.5	million	/	9.1%
Gas	$	46.1	million	/	9.6%
Steam	$	7.6	million	/	35.3%
ROE	9.8%
Common equity component average on a financial basis	53.0%

In addition to the above, the final order included the following terms:

•We will keep our current earnings sharing mechanism, under which, if we earn above our authorized ROE: (i) we retain 100.0% of earnings for the first 15 basis points above the authorized ROE; (ii) 50.0% of the next 60 basis points is refunded to ratepayers; and (iii) 100.0% of any remaining excess earnings is required to be refunded to ratepayers.

•We were required to complete an analysis of alternative recovery scenarios for generating units that will be retired prior to the end of their useful life.

•We will not propose any changes to our real time pricing rates for large commercial and industrial electric customers through the end of 2024.

•We were required to lower monthly residential and small commercial electric customer fixed charges by $1.00 from previously authorized rates.

•We were required to offer an additional voluntary renewable energy pilot for commercial and industrial customers.

•We will continue to work with PSCW staff and other interested parties to develop alternative low income assistance programs. We, along with WPS, also collectively contributed $4.0 million to the Keep Wisconsin Warm Fund.

•We were required to implement escrow accounting treatment for pension and OPEB costs in 2023 and 2024.

•As discussed above, we were authorized to file a limited electric and natural gas rate case re-opener for 2024.

2022 Rates

In March 2021, we filed an application with the PSCW for the approval of certain accounting treatments that allowed us to maintain our electric, natural gas, and steam base rates through 2022 and forego filing a rate case for one year. In connection with the request, we also entered into an agreement, dated March 23, 2021, with various stakeholders. Pursuant to the terms of the agreement, the stakeholders fully supported the application. In September 2021, the PSCW issued a written order approving the application.

The final order reflected the following:

•We amortized, in 2022, certain previously deferred balances to offset approximately half of our forecasted revenue deficiency.

•We were able to defer any increases in tax expense due to changes in tax law that occurred in 2021 and/or 2022.

•We maintained our earnings sharing mechanism for 2022, with modification. The earnings sharing mechanism was modified to authorize us to retain 100.0% of the first 15 basis points of earnings above our then authorized ROE. The earnings sharing mechanism otherwise remained as previously authorized.

2020 and 2021 Rates

In March 2019, we filed an application with the PSCW to increase our retail electric, natural gas, and steam rates, effective January 1, 2020. In August 2019, we filed an application with the PSCW for approval of a settlement agreement entered into with certain intervenors to resolve several outstanding issues in our rate case. In December 2019, the PSCW issued a written order that approved the settlement agreement without material modification and addressed the remaining outstanding issues that were not included in the settlement agreement. The new rates were effective January 1, 2020. The final order reflected the following:

2020 Effective rate increase
Electric (1)	$	15.3	million	/	0.5%
Gas (2)	$	10.4	million	/	2.8%
Steam	$	1.9	million	/	8.6%
ROE	10.0%
Common equity component average on a financial basis	52.5%

(1)    Amount is net of certain deferred tax benefits from the Tax Legislation that were utilized to reduce near-term rate impacts. The rate order reflected the majority of the unprotected deferred tax benefits from the Tax Legislation being amortized evenly over two years, which resulted in approximately $65 million of tax benefits being amortized in each of 2020 and 2021. The unprotected deferred tax benefits related to the unrecovered balances of certain of our retired plants and our SSR regulatory asset were used to reduce the related regulatory asset. Unprotected deferred tax benefits by their nature are eligible to be returned to customers in a manner and timeline determined to be appropriate by the PSCW.

(2)    Amount includes certain deferred tax expense from the Tax Legislation. The rate order reflected all of the unprotected deferred tax expense from the Tax Legislation being amortized evenly over four years, which resulted in approximately $5 million of previously deferred tax expense being amortized each year. Unprotected deferred tax expense by its nature is eligible to be recovered from customers in a manner and timeline determined to be appropriate by the PSCW.

In accordance with our rate order, we filed an application with the PSCW in July 2020 requesting a financing order to securitize $100 million of Pleasant Prairie power plant's book value, plus the carrying costs accrued on the $100 million during the securitization process and the related financing fees. In November 2020, the PSCW issued a written order approving the application. The financing order also authorized us to form a bankruptcy-remote special purpose entity, WEPCo Environmental Trust, for the sole purpose of issuing ETBs to recover the approved costs. In May 2021, WEPCo Environmental Trust issued $118.8 million of 1.578% ETBs due December 15, 2035. See Note 21, Variable Interest Entities, for more information on WEPCo Environmental Trust.

The PSCW approved us continuing to have an earnings sharing mechanism through 2021. The earnings sharing mechanism was modified from its previous structure to one that was consistent with other Wisconsin investor-owned utilities. Under this earnings sharing mechanism, if we earned above our authorized ROE: (i) we retained 100.0% of earnings for the first 25 basis points above the authorized ROE; (ii) 50.0% of the next 50 basis points were required to be refunded to customers; and (iii) 100.0% of any remaining excess earnings were required to be refunded to customers. In addition, the rate order also required us to maintain residential and small commercial electric and natural gas customer fixed charges at previously authorized rates and to maintain the status quo for our electric market-based rate programs for large industrial customers through 2021.

Recovery of Natural Gas Costs

Due to the cold temperatures, wind, snow, and ice throughout the central part of the country during February 2021, the cost of gas purchased for our natural gas utility customers was temporarily driven significantly higher than our normal winter weather expectations. We have a regulatory mechanism in place for recovering all prudently incurred gas costs.

In March 2021, we received approval from the PSCW to recover approximately $54 million of natural gas costs in excess of the benchmark set in our GCRM over a period of three months, beginning in April 2021.

XML

Other Income, Net

12 Months Ended

Dec. 31, 2023

Other Income and Expenses [Abstract]

OTHER INCOME, NET

OTHER INCOME, NET

Total other income, net was as follows for the years ended December 31:

(in millions)	2023		2022		2021
AFUDC-Equity	$	41.0	$	18.8	$	7.9
Non-service components of net periodic benefit costs	24.1		33.8		22.5
Other, net	3.7		(3.2)		1.7
Other income, net	$	68.8	$	49.4	$	32.1

XML

New Accounting Pronouncements

12 Months Ended

Dec. 31, 2023

Accounting Standards Update and Change in Accounting Principle [Abstract]

NEW ACCOUNTING PRONOUNCEMENTS

NEW ACCOUNTING PRONOUNCEMENTS

Improvements to Income Tax Disclosures

In December 2023, the FASB issued ASU No. 2023-09, Income Taxes (Topic 740): Improvements to Income Tax Disclosures. The amendments require additional disclosures, primarily related to income taxes paid and the rate reconciliation table. The amendments require disclosures on specific categories in the rate reconciliation table, as well as additional information for reconciling items that meet a quantitative threshold. For income taxes paid, additional disclosures are required to disaggregate federal, state, and foreign income taxes paid, with additional disclosures for income taxes paid that meet a quantitative threshold. The amendments are effective for annual periods beginning after December 15, 2024, with early adoption permitted. We plan to adopt these amendments beginning with our fiscal year ending on December 31, 2025, and are currently evaluating the impact this guidance may have on our financial statements and related disclosures.

Improvements to Reportable Segment Disclosures

In November 2023, the FASB issued ASU No. 2023-07, Segment Reporting (Topic 280): Improvements to Reportable Segment Disclosures. The amendments require additional disclosures about reportable segments on an annual and interim basis. The amendments require disclosure of significant segment expenses that are (1) regularly provided to the chief operating decision maker and (2) included in the reported measure of segment profit or loss. The amendments also require disclosure of an amount for other segment items and a description of its composition. The new standard also allows companies to disclose multiple measures of segment profit or loss if those measures are used to assess performance and allocate resources. The amendments are effective for fiscal years beginning after December 15, 2023, and interim periods within fiscal years beginning after December 15, 2024, with early adoption permitted. We plan to adopt these amendments beginning with our fiscal year ending on December 31, 2024, and are currently evaluating the impact this guidance may have on our financial statements and related disclosures.

Reference Rate Reform

In March 2020, the FASB issued ASU No. 2020-04, Reference Rate Reform (Topic 848): Facilitation of the Effects of Reference Rate Reform on Financial Reporting and in January 2021, the FASB issued ASU No. 2021-01, Reference Rate Reform (Topic 848): Scope. These pronouncements provide temporary optional expedients and exceptions for applying GAAP principles to contract modifications and hedging relationships to ease the financial reporting burdens of the market transition from LIBOR and other interbank offered rates to alternative reference rates. These pronouncements were effective upon issuance on March 12, 2020 through December 31, 2022. In December 2022, the FASB issued ASU No. 2022-06, Reference Rate Reform (Topic 848): Deferral of the Sunset Date of Topic 848, to extend the temporary accounting rules under Topic 848 from December 31, 2022 to December 31, 2024, after which entities will no longer be permitted to apply the relief in Topic 848. An entity may elect to apply the amendments prospectively from March 12, 2020 through December 31, 2024 by accounting topic. We do not anticipate this guidance having a significant impact on our financial statements and related disclosures.

XML

Schedule II - Valuation and Qualifying Accounts

12 Months Ended

Dec. 31, 2023

SEC Schedule, 12-09, Valuation and Qualifying Accounts [Abstract]

SCHEDULE II - VALUATION AND QUALIFYING ACCOUNTS

SCHEDULE II

WISCONSIN ELECTRIC POWER COMPANY

VALUATION AND QUALIFYING ACCOUNTS

Allowance for Doubtful Accounts (in millions)	Balance at Beginning of Period		Expense (1)		Deferral		Net Write-offs (2)		Balance at End of Period
December 31, 2023	$	49.7	$	23.8	$	45.7	$	(74.7)	$	44.5
December 31, 2022	51.4		27.3		34.0		(63.0)		49.7
December 31, 2021	59.3		24.8		(0.3)		(32.4)		51.4

(1)    Net of recoveries.

(2)    Represents amounts written off to the reserve, net of adjustments to regulatory assets.

XML

Insider Trading Arrangements	3 Months Ended
	Dec. 31, 2023
Trading Arrangements, by Individual
Rule 10b5-1 Arrangement Adopted	false
Non-Rule 10b5-1 Arrangement Adopted	false
Rule 10b5-1 Arrangement Terminated	false
Non-Rule 10b5-1 Arrangement Terminated	false

XML

Summary of Significant Accounting Policies (Policies)

12 Months Ended

Dec. 31, 2023

Accounting Policies [Abstract]

Nature of operations

We are an electric, natural gas, and steam utility company that serves electric and natural gas customers in Wisconsin, and steam customers in metropolitan Milwaukee, Wisconsin. WEC Energy Group owns all of our outstanding common stock.

Consolidation

As used in these notes, the term "financial statements" refers to the consolidated financial statements. This includes the income statements, balance sheets, statements of cash flows, and statements of equity, unless otherwise noted. On our financial statements, we consolidate VIEs of which we are the primary beneficiary.

Jointly owned facilities

These financial statements reflect our proportionate interests in certain jointly owned utility facilities. See Note 9, Jointly Owned Utility Facilities, for more information.

Basis of presentation

We prepare our financial statements in conformity with GAAP.

Use of estimates

We make estimates and assumptions that affect the reported amounts of assets and liabilities, the disclosure of contingent assets and liabilities at the date of the financial statements, and the reported amounts of revenues and expenses during the reporting period. Actual results may differ from these estimates.

Cash and cash equivalents

Cash and cash equivalents include marketable debt securities with an original maturity of three months or less.

Operating revenues

The following discussion includes our significant accounting policies related to operating revenues. For additional required disclosures on disaggregation of operating revenues, see Note 5, Operating Revenues.

Revenues from Contracts with Customers

Electric Utility Operating Revenues

Electricity sales to residential and commercial and industrial customers are generally accomplished through requirements contracts, which provide for the delivery of as much electricity as the customer needs. These contracts represent discrete deliveries of electricity and consist of one distinct performance obligation satisfied over time, as the electricity is delivered and consumed by the customer simultaneously. For our residential and commercial and industrial customers, our performance obligation is bundled to consist of both the sale and the delivery of the electric commodity.

The transaction price of the performance obligations for residential and commercial and industrial customers is valued using the rates, charges, terms, and conditions of service included in our tariffs, which have been approved by the PSCW. These rates often have a fixed component customer charge and a usage-based variable component charge. We recognize revenue for the fixed component customer charge monthly using a time-based output method. We recognize revenue for the usage-based variable component charge using an output method based on the quantity of electricity delivered each month. Our retail electric rates in Wisconsin include base amounts for fuel and purchased power costs, which also impact our revenues. The electric fuel rules set by the PSCW allow us to defer, for subsequent rate recovery or refund, under- or over-collections of actual fuel and purchased power costs beyond a 2% price variance from the costs included in the rates charged to customers. We monitor the deferral of under-collected costs to ensure that it does not cause us to earn a greater ROE than authorized by the PSCW. In addition, our residential tariffs include a mechanism for cost recovery or refund of uncollectible expense based on the difference between actual uncollectible write-offs and the amounts recovered in rates.

Wholesale customers who resell power can choose to either bundle capacity and electricity services together under one contract with a supplier or purchase capacity and electricity separately from multiple suppliers. Furthermore, wholesale customers can choose to have us provide generation to match the customer's load, similar to requirements contracts, or they can purchase specified quantities of electricity and capacity. Contracts with wholesale customers that include capacity bundled with the delivery of electricity contain two performance obligations, as capacity and electricity are often transacted separately in the marketplace at the wholesale level. When recognizing revenue associated with these contracts, the transaction price is allocated to each performance obligation based on its relative standalone selling price. Revenue is recognized as control of each individual component is transferred to the customer. Electricity is the primary product sold by our electric operations and represents a single performance

obligation satisfied over time through discrete deliveries to a customer. Revenue from electricity sales is generally recognized as units are produced and delivered to the customer within the production month. Capacity represents the reservation of an electric generating facility and conveys the ability to call on a plant to produce electricity when needed by the customer. The nature of our performance obligation as it relates to capacity is to stand ready to deliver power. This represents a single performance obligation transferred over time, which generally represents a monthly obligation. Accordingly, capacity revenue is recognized on a monthly basis.

The transaction price of the performance obligations for wholesale customers is valued using the rates, charges, terms, and conditions of service, which have been approved by the FERC. These wholesale rates include recovery of fuel and purchased power costs from customers on a one-for-one basis. For the majority of our wholesale customers, the price billed for energy and capacity is a formula-based rate. Formula-based rates initially set a customer's current year rates based on the previous year’s expenses. This is a predetermined formula derived from the utility’s costs and a reasonable rate of return. Because these rates are eventually trued up to reflect actual current-year costs, they represent a form of variable consideration in certain circumstances. The variable consideration is estimated and recognized over time as wholesale customers receive and consume the capacity and electricity services.

We are an active participant in the MISO Energy Markets, where we bid our generation into the Day Ahead and Real Time markets and procure electricity for our retail and wholesale customers at prices determined by the MISO Energy Markets. Purchase and sale transactions are recorded using settlement information provided by MISO. These purchase and sale transactions are accounted for on a net hourly position. Net purchases in a single hour are recorded as purchased power in cost of sales and net sales in a single hour are recorded as resale revenues on our income statements. For resale revenues, our performance obligation is created only when electricity is sold into the MISO Energy Markets.

For all of our customers, consistent with the timing of when we recognize revenue, customer billings generally occur on a monthly basis, with payments typically due in full within 30 days.

Natural Gas Utility Operating Revenues

We recognize natural gas utility operating revenues under requirements contracts with residential, commercial and industrial, and transportation customers served under our tariffs. Tariffs provide our customers with the standard terms and conditions, including rates, related to the services offered. Requirements contracts provide for the delivery of as much natural gas as the customer needs. These requirements contracts represent discrete deliveries of natural gas and constitute a single performance obligation satisfied over time. Our performance obligation is both created and satisfied with the transfer of control of natural gas upon delivery to the customer. For most of our customers, natural gas is delivered and consumed by the customer simultaneously. A performance obligation can be bundled to consist of both the sale and the delivery of the natural gas commodity. In Wisconsin, our customers can purchase the commodity from a third party. In this case, the performance obligation only includes the delivery of the natural gas to the customer.

The transaction price of the performance obligations for our natural gas customers is valued using the rates, charges, terms, and conditions of service included in our tariffs, which have been approved by the PSCW. These rates often have a fixed component customer charge and a usage-based variable component charge. We recognize revenue for the fixed component customer charge monthly using a time-based output method. We recognize revenue for the usage-based variable component charge using an output method based on natural gas delivered each month.

Our tariffs include various rate mechanisms that allow us to recover or refund changes in prudently incurred costs from rate case-approved amounts. Our rates include a one-for-one recovery mechanism for natural gas commodity costs. Under normal circumstances, we defer any difference between actual natural gas costs incurred and costs recovered through rates as a current asset or liability. The deferred balance is returned to or recovered from customers at intervals throughout the year. However, as a result of the extreme weather in the Midwest in February 2021, the cost of gas purchased for our natural gas customers was temporarily driven significantly higher than our normal winter weather expectations. See Note 24, Regulatory Environment, for more information on the recovery of these high natural gas costs.

In addition, our residential tariffs include a mechanism for cost recovery or refund of uncollectible expense based on the difference between actual uncollectible write-offs and the amounts recovered in rates.

Consistent with the timing of when we recognize revenue, customer billings generally occur on a monthly basis, with payments typically due in full within 30 days.

Other Operating Revenues

Alternative Revenues

Alternative revenues are created from programs authorized by regulators that allow us to record additional revenues by adjusting rates in the future, usually as a surcharge applied to future billings, in response to past activities or completed events. We record alternative revenues when the regulator-specified conditions for recognition have been met. We reverse these alternative revenues as the customer is billed, at which time this revenue is presented as revenues from contracts with customers.

Our only alternative revenue program relates to the wholesale electric service that we provide to customers under market-based rates and FERC formula rates. The customer is charged a base rate each year based upon a formula using prior year actual costs and customer demand. A true-up is calculated based on the difference between the amount billed to customers for the demand component of their rates and what the actual cost of service was for the year. The true-up can result in an amount that we will recover from or refund to the customer. We consider the true-up portion of the wholesale electric revenues to be alternative revenues.

Credit losses

The following discussion includes our significant accounting policies related to credit losses. For additional required disclosures on credit losses, see Note 6, Credit Losses.

Our exposure to credit losses is related to our accounts receivable and unbilled revenue balances, which are generated from the sale of electricity and natural gas by our regulated utility operations. Our regulated utility operations are included in our utility segment. No accounts receivable and unbilled revenue balances were reported in the other segment at December 31, 2023 and 2022.

We evaluate the collectability of our accounts receivable and unbilled revenue balances considering a combination of factors. For some of our larger customers and also in circumstances where we become aware of a specific customer's inability to meet its financial obligations to us, we record a specific allowance for credit losses against amounts due in order to reduce the net recognized receivable to the amount we reasonably believe will be collected. For all other customers, we use the accounts receivable aging method to calculate an allowance for credit losses. Using this method, we classify accounts receivable into different aging buckets and calculate a reserve percentage for each aging bucket based upon historical loss rates. The calculated reserve percentages are updated on at least an annual basis, in order to ensure recent macroeconomic, political, and regulatory trends are captured in the calculation, to the extent possible. Risks identified that we do not believe are reflected in the calculated reserve percentages, are assessed on a quarterly basis to determine whether further adjustments are required.

We monitor our ongoing credit exposure through active review of counterparty accounts receivable balances against contract terms and due dates. Our activities include timely account reconciliation, dispute resolution and payment confirmation. To the extent possible, we work with customers with past due balances to negotiate payment plans, but will disconnect customers for non-payment as allowed by the PSCW, if necessary, and employ collection agencies and legal counsel to pursue recovery of defaulted receivables. For our larger customers, detailed credit review procedures may be performed in advance of any sales being made. We sometimes require letters of credit, parental guarantees, prepayments or other forms of credit assurance from our larger customers to mitigate credit risk.

Materials, supplies and inventories

Our inventories as of December 31 consisted of:

(in millions)	2023		2022
Materials and supplies	$	186.6	$	150.6
Fossil fuel	74.5		62.7
Natural gas in storage	49.5		79.6
Total	$	310.6	$	292.9

Substantially all materials and supplies, fossil fuel, and natural gas in storage inventories are recorded using the weighted-average cost method of accounting.

Regulatory assets and liabilities

The economic effects of regulation can result in regulated companies recording costs and revenues that are allowed in the ratemaking process in a period different from the period they would have been recognized by a nonregulated company. When this occurs, regulatory assets and regulatory liabilities are recorded on the balance sheet. Regulatory

assets represent deferred costs probable of recovery from customers that would have otherwise been charged to expense. Regulatory liabilities represent amounts that are expected to be refunded to customers in future rates or future costs already collected from customers in rates.

The recovery or refund of regulatory assets and liabilities is based on specific periods determined by our regulators or occurs over the normal operating period of the related assets and liabilities. If a previously recorded regulatory asset is no longer probable of recovery, the regulatory asset is reduced to the amount considered probable of recovery, and the reduction is charged to expense in the current period. See Note 7, Regulatory Assets and Liabilities, for more information.

Property, plant, and equipment

We record property, plant, and equipment at cost. Cost includes material, labor, overhead, and both debt and equity components of AFUDC. Additions to and significant replacements of property are charged to property, plant, and equipment at cost; minor items are charged to other operation and maintenance expense. The cost of depreciable utility property less salvage value is charged to accumulated depreciation when property is retired.

We record straight-line depreciation expense over the estimated useful life of utility property using depreciation rates approved by the PSCW that include estimates for salvage value and removal costs. Annual utility composite depreciation rates were 3.03%, 3.06%, and 3.09% in 2023, 2022, and 2021, respectively.

We capitalize certain costs related to software developed or obtained for internal use and record these costs to amortization expense over the estimated useful life of the related software, which ranges from 3 to 15 years. If software is retired prior to being fully amortized, the difference is recorded as a loss on the income statement.

Third parties reimburse us for all or a portion of expenditures for certain capital projects. Such contributions in aid of construction costs are recorded as a reduction to property, plant, and equipment.

See Note 8, Property, Plant, and Equipment, for more information.

AFUDC

AFUDC is included in utility plant accounts and represents the cost of borrowed funds (AFUDC-Debt) used during plant construction, and a return on shareholders' capital (AFUDC-Equity) used for construction purposes. AFUDC-Debt is recorded as a reduction of interest expense, and AFUDC-Equity is recorded in other income, net.

Approximately 50% of our retail jurisdictional CWIP expenditures are subject to the AFUDC calculation. Our average AFUDC retail rates were 8.45%, 8.68%, and 8.68% for 2023, 2022, and 2021, respectively. Our average AFUDC wholesale rates were 6.70%, 5.35%, and 1.79% for 2023, 2022, and 2021, respectively.

We recorded the following AFUDC for the years ended December 31:

(in millions)	2023		2022		2021
AFUDC-Debt	$	13.0	$	6.9	$	2.9
AFUDC-Equity	41.0		18.8		7.9

Impairment of intangible assets

Intangible assets with indefinite lives are subject to an annual impairment test. Interim impairment tests are performed when impairment indicators are present. At December 31, 2023 and 2022, we had $12.1 million and $9.1 million, respectively, of indefinite-lived intangible assets consisting of spectrum frequencies purchased in 2022 and 2023. The spectrum frequencies enable us to transmit data and voice communications over a wavelength dedicated to us throughout our service territory. These indefinite-lived intangible assets are included in other long-term assets on our balance sheets. An impairment loss is recognized when the carrying amount of an asset is not recoverable and exceeds its fair value. An impairment loss is measured as the excess of the carrying amount of the intangible asset over its fair value. No impairment losses were recorded for our indefinite-lived intangible assets during the years ended December 31, 2023 and 2022.

Impairment of long-lived assets

We periodically assess the recoverability of certain long-lived assets when factors indicate the carrying value of such assets may be impaired or such assets are planned to be sold. Long-lived assets that would be subject to an impairment assessment generally include any assets within regulated operations that may not be fully recovered from our customers as a result of regulatory decisions that will be made in the future. An impairment loss is recognized when the carrying amount of an asset is not recoverable and exceeds its fair value. The carrying amount of an asset is not recoverable if it exceeds the sum of the undiscounted cash flows

expected to result from the use and eventual disposition of the asset. An impairment loss is measured as the excess of the carrying amount of the asset over its fair value.

We assess the likelihood of a disallowance of part of the cost of recently completed plant by considering factors such as applicable regulatory environment changes, our own recent rate orders, as well as recent rate orders of other regulated entities in similar jurisdictions. When it becomes probable that part of the cost of recently completed plant will be disallowed for rate-making purposes, we assess whether a reasonable estimate of the amount of the disallowance can be made. The estimated amount of the probable disallowance will then be deducted from the reported cost of the plant and recognized as an impairment loss.

When it becomes probable that a generating unit will be retired before the end of its useful life, we assess whether the generating unit meets the criteria for abandonment accounting. Generating units that are considered probable of abandonment are expected to cease operations in the near term, significantly before the end of their original estimated useful lives. If a generating unit meets the applicable criteria to be considered probable of abandonment, and the unit has been abandoned, we assess the likelihood of recovery of the remaining net book value of that generating unit at the end of each reporting period. If it becomes probable that regulators will disallow full recovery as well as a return on the remaining net book value of a generating unit that is either abandoned or probable of being abandoned, an impairment loss may be required. An impairment loss would be recorded if the remaining net book value of the generating unit is greater than the present value of the amount expected to be recovered from ratepayers, using an incremental borrowing rate. See Note 7, Regulatory Assets and Liabilities, and Note 8, Property, Plant, and Equipment, for more information.

Asset retirement obligations

We recognize, at fair value, legal obligations associated with the retirement of long-lived assets that result from the acquisition, construction, development, and normal operation of the assets. An ARO liability is recorded, when incurred, for these obligations as long as the fair value can be reasonably estimated, even if the timing or method of settling the obligation is unknown. The associated retirement costs are capitalized as part of the related long-lived asset and are depreciated over the useful life of the asset. The ARO liabilities are accreted each period using the credit-adjusted risk-free interest rates associated with the expected settlement dates of the AROs. These rates are determined when the obligations are incurred. Subsequent changes resulting from revisions to the timing or the amount of the original estimate of undiscounted cash flows are recognized as an increase or a decrease to the carrying amount of the liability and the associated capitalized retirement costs. We recognize regulatory assets or liabilities for the timing differences between when we recover an ARO in rates and when we recognize the associated retirement costs. See Note 10, Asset Retirement Obligations, for more information.

Stock-based compensation

Our employees participate in the WEC Energy Group stock-based compensation plans. In accordance with the Omnibus Stock Incentive Plan, WEC Energy Group provides long-term incentives through its equity interests to its non-employee directors, officers, and other key employees. The plan provides for the granting of stock options, restricted stock, performance shares, and other stock-based awards. Awards may be paid in WEC Energy Group common stock, cash, or a combination thereof. In addition to those shares of WEC Energy Group common stock that were subject to awards outstanding as of May 6, 2021, when the plan was last approved by shareholders, 9.0 million shares of WEC Energy Group common stock were reserved for issuance under the plan.

Stock-based compensation expense is allocated to us based on the outstanding awards held by our employees and our allocation of labor costs. Awards classified as equity awards are measured based on their grant-date fair value. Awards classified as liability awards are recorded at fair value each reporting period. We account for forfeitures as they occur, rather than estimating potential future forfeitures and recording them over the vesting period.

Stock Options

Our employees are granted WEC Energy Group non-qualified stock options that generally vest on a cliff-basis after three years. The exercise price of a stock option under the plan cannot be less than 100% of the fair market value of WEC Energy Group common stock on the grant date. Historically, all stock options have been granted with an exercise price equal to the fair market value of WEC Energy Group common stock on the date of the grant. Options vest immediately upon retirement, death, or disability; however, they may not be exercised within six months of the grant date except in connection with certain termination of employment events following a change in control. Options expire no later than 10 years from the date of grant.

WEC Energy Group stock options are classified as equity awards. The fair value of each stock option was calculated using a binomial option-pricing model. The following table shows the estimated weighted-average fair value per stock option granted to our employees along with the weighted-average assumptions used in the valuation models:

	2023			2022			2021
Stock options granted	30,495			51,511			60,108
Estimated weighted-average fair value per stock option	$	19.58		$	14.71		$	13.20
Assumptions used to value the options:
Risk-free interest rate	3.8% – 4.8%			0.2% – 1.6%			0.1% – 0.9%
Dividend yield	3.2		%	3.2		%	2.9		%
Expected volatility	22.0		%	21.0		%	21.0		%
Expected life (years)	8.3			8.7			8.7

The risk-free interest rate was based on the United States Treasury interest rate with a term consistent with the expected life of the stock options. The dividend yield was based on WEC Energy Group's dividend rate at the time of the grant and historical stock prices. Expected volatility and expected life assumptions were based on WEC Energy Group's historical experience.

Restricted Shares

WEC Energy Group restricted shares granted to our employees have a vesting period of three years with one-third of the award vesting on each anniversary of the grant date. The restricted shares are classified as equity awards.

Performance Units

Officers and other key employees are granted performance units under the WEC Energy Group Performance Unit Plan. All grants of performance units are settled in cash and are accounted for as liability awards accordingly. Performance units accrue forfeitable dividend equivalents in the form of additional performance units. The fair value of the performance units reflects our estimate of the final expected value of the awards, which is based on WEC Energy Group's stock price and performance achievement under the terms of the award. Stock-based compensation costs are generally recorded over the performance period, which is three years.

The ultimate number of units that will be awarded is dependent on WEC Energy Group's total shareholder return (stock price appreciation plus dividends) as compared to the total shareholder return of a peer group of companies over three years, as well as other performance metrics, as may be determined by the Compensation Committee. Under the terms of awards granted prior to 2023, participants may earn between 0% and 175% of the performance unit award based on WEC Energy Group's total shareholder return. Pursuant to the plan terms governing these awards, these percentages can be adjusted upwards or downwards by up to 10% based on WEC Energy Group's performance against additional performance measures, if any, adopted by the Compensation Committee.

The WEC Energy Group Performance Unit Plan was amended and restated, effective January 1, 2023. In accordance with the amended plan, the Compensation Committee selected multiple performance measures that will be weighted to determine the ultimate payout for the awards granted in 2023 and 2024. The ultimate number of units awarded will be based on WEC Energy Group's total shareholder return compared to the total shareholder return of a peer group of companies over three years (55%), and WEC Energy Group's performance against the weighted average authorized ROE of all of its utility subsidiaries (45%). In addition, the Compensation Committee selected the level of WEC Energy Group's stock price to earnings ratio compared to its peer companies as a performance measure that can increase the payout by up to 25%. In no event can the performance unit payout be greater than 200% of the target award.

See Note 11, Common Equity, for more information on WEC Energy Group's stock-based compensation plans.

Stock-based compensation - forfeitures

We account for forfeitures as they occur, rather than estimating potential future forfeitures and recording them over the vesting period

Leases

We recognize a right of use asset and lease liability for operating and finance leases with a term of greater than one year. As a policy election, we account for each lease component separately from the nonlease components of a contract.

We are currently party to several easement agreements that allow us access to land we do not own for the purpose of constructing and maintaining certain electric power and natural gas equipment. The majority of payments we make related to easements relate

to our renewable generating facilities. We have not classified our easements as leases because we view the entire parcel of land specified in our easement agreements to be the identified asset, not just that portion of the parcel that contains our easement. As such, we have concluded that we do not control the use of an identified asset related to our easement agreements, nor do we obtain substantially all of the economic benefits associated with these shared-use assets.

See Note 15, Leases, for more information.

Income taxes

We follow the liability method in accounting for income taxes. Accounting guidance for income taxes requires the recording of deferred assets and liabilities to recognize the expected future tax consequences of events that have been reflected in our financial statements or tax returns and the adjustment of deferred tax balances to reflect tax rate changes. We are required to assess the likelihood that our deferred tax assets would expire before being realized. If we conclude that certain deferred tax assets are likely to expire before being realized, a valuation allowance would be established against those assets. GAAP requires that, if we conclude in a future period that it is more likely than not that some or all of the deferred tax assets would be realized before expiration, we reverse the related valuation allowance in that period. Any change to the allowance, as a result of a change in judgment about the realization of deferred tax assets, is reported in income tax expense.

ITCs associated with regulated operations are deferred and amortized over the life of the assets. PTCs are recognized in the period in which such credits are generated. The amount of the credit is based upon power production from our qualifying generation facilities. We are included in WEC Energy Group's consolidated federal and state income tax returns. In accordance with our tax allocation agreement with WEC Energy Group, we are allocated income tax payments and refunds based upon the benefit for loss method, where attributes are realized when WEC Energy Group is able to realize them.

We recognize interest and penalties accrued related to unrecognized tax benefits in income tax expense in our income statements.

The IRA contains a tax credit transferability provision that allows us to sell PTCs produced after December 31, 2022, to third parties. In September 2023, under this transferability provision, WEC Energy Group entered into an agreement to sell substantially all of our 2023 PTCs to a third party. We elect to account for tax credits transferred under the scope of ASC 740. We include the discount from the sale of tax credits as a component of income tax expense. We will also include any expected proceeds from the sale of tax credits in the evaluation of the realizability of deferred tax assets related to PTCs. The sale of tax credits is presented in the operating activities section of the statements of cash flows consistent with the presentation of cash taxes paid.

In April 2023, the IRS issued Revenue Procedure 2023-15, which provides a safe harbor method of accounting that taxpayers may use to determine whether expenses to repair, maintain, replace, or improve natural gas transmission and distribution property must be capitalized for tax purposes. We are currently evaluating the impact this guidance may have on our financial statements and related disclosures.

See Note 16, Income Taxes, for more information.

Fair value measurements

Fair value is the price that would be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants at the measurement date (exit price).

Fair value accounting rules provide a fair value hierarchy that prioritizes the inputs used to measure fair value. The hierarchy gives the highest priority to unadjusted quoted prices in active markets for identical assets or liabilities (Level 1 measurement) and the lowest priority to unobservable inputs (Level 3 measurement). The three levels of the fair value hierarchy are defined as follows:

Level 1 – Quoted prices are available in active markets for identical assets or liabilities as of the reporting date. Active markets are those in which transactions for the asset or liability occur in sufficient frequency and volume to provide pricing information on an ongoing basis.

Level 2 – Pricing inputs are observable, either directly or indirectly, but are not quoted prices included within Level 1. Level 2 includes those financial instruments that are valued using external inputs within models or other valuation methods.

Level 3 – Pricing inputs include significant inputs that are generally less observable from objective sources. These inputs may be used with internally developed methods that result in management's best estimate of fair value. Level 3 instruments include those that may be more structured or otherwise tailored to customers' needs.

Assets and liabilities are classified in their entirety based on the lowest level of input that is significant to the fair value measurement. We use a mid-market pricing convention (the mid-point price between bid and ask prices) as a practical measure for valuing certain derivative assets and liabilities. We primarily use a market approach for recurring fair value measurements and attempt to use valuation techniques that maximize the use of observable inputs and minimize the use of unobservable inputs.

When possible, we base the valuations of our derivative assets and liabilities on quoted prices for identical assets and liabilities in active markets. These valuations are classified in Level 1. The valuations of certain contracts not classified as Level 1 may be based on quoted market prices received from counterparties and/or observable inputs for similar instruments. Transactions valued using these inputs are classified in Level 2. Certain derivatives, such as FTRs, are categorized in Level 3 due to the significance of unobservable or internally-developed inputs. Our FTRs are valued using MISO auction prices.

See Note 17, Fair Value Measurements, for more information.

Derivative instruments

We use derivatives as part of our risk management program to manage the risks associated with the price volatility of purchased power, generation, and natural gas costs for the benefit of our customers. Our approach is non-speculative and designed to mitigate risk. Our regulated hedging programs are approved by the PSCW.

We record derivative instruments on our balance sheets as assets or liabilities measured at fair value, unless they qualify for the normal purchases and sales exception, and are so designated. We continually assess our contracts designated as normal and will discontinue the treatment of these contracts as normal if the required criteria are no longer met. Changes in the derivative's fair value are recognized currently in earnings unless specific hedge accounting criteria are met or we receive regulatory treatment for the derivative. For most energy related physical and financial contracts in our regulated operations that qualify as derivatives, the PSCW allows the effects of fair value accounting to be offset to regulatory assets and liabilities.

We classify derivative assets and liabilities as current or long-term on our balance sheets based on the maturities of the underlying contracts. Cash flows from derivative activities are presented in the same category as the item being hedged within operating activities on our statements of cash flows.

Derivative accounting rules provide the option to present certain asset and liability derivative positions net on the balance sheets and to net the related cash collateral against these net derivative positions. We elected not to net these items. On our balance sheets, cash collateral provided to others is reflected in other current assets. See Note 18, Derivative Instruments, for more information.

Guarantees

We follow the guidance of the Guarantees Topic of the FASB ASC, which requires, under certain circumstances, that the guarantor recognize a liability for the fair value of the obligation undertaken in issuing the guarantee at its inception. As of December 31, 2023, we had $26.0 million of standby letters of credit issued by financial institutions for the benefit of third parties that have extended credit to us, which automatically renew each year unless proper termination notice is given. These amounts are not reflected on our balance sheets.

Employee benefits

The costs of pension and OPEB plans are expensed over the periods during which employees render service. These costs are distributed among WEC Energy Group's subsidiaries based on current employment status and actuarial calculations, as applicable. Our regulators allow recovery in rates for our net periodic benefit cost calculated under GAAP. See Note 19, Employee Benefits, for more information.

Customer deposits and credit balances

When utility customers apply for new service, they may be required to provide a deposit for the service. Customer deposits are recorded within other current liabilities on our balance sheets.

Utility customers can elect to be on a budget plan. Under this type of plan, a monthly installment amount is calculated based on estimated annual usage. During the year, the monthly installment amount is reviewed by comparing it to actual usage. If necessary, an adjustment is made to the monthly amount. Annually, the budget plan is reconciled to actual annual usage. Payments in excess of actual customer usage are recorded within other current liabilities on our balance sheets.

Environmental remediation costs

We are subject to federal and state environmental laws and regulations that in the future may require us to pay for environmental remediation at sites where we have been, or may be, identified as a potentially responsible party. Loss contingencies may exist for the remediation of hazardous substances at various potential sites, including CCR

landfills and manufactured gas plant sites. See Note 10, Asset Retirement Obligations, for more information regarding CCR landfills and Note 22, Commitments and Contingencies, for more information regarding manufactured gas plant sites.

We record environmental remediation liabilities when site assessments indicate remediation is probable, and we can reasonably estimate the loss or a range of losses. The estimate includes both our share of the liability and any additional amounts that will not be paid by other potentially responsible parties or the government. When possible, we estimate costs using site-specific information but also consider historical experience for costs incurred at similar sites. Remediation efforts for a particular site generally extend over a period of several years. During this period, the laws governing the remediation process may change, as well as site conditions, potentially affecting the cost of remediation.

We have received approval to defer certain environmental remediation costs, as well as estimated future costs, through a regulatory asset. The recovery of deferred costs is subject to the PSCW's approval.

We review our estimated costs of remediation annually for our manufactured gas plant sites and CCR landfills. We adjust the liabilities and related regulatory assets, as appropriate, to reflect the new cost estimates. Any material changes in cost estimates are adjusted throughout the year.

Customer concentrations of credit risk

The geographic concentration of our customers did not contribute significantly to our overall exposure to credit risk. We periodically review customers' credit ratings, financial statements, and historical payment performance and require them to provide collateral or other security as needed. Our credit risk exposure is mitigated by our recovery mechanism for uncollectible expense discussed in Note 1(d), Operating Revenues. As a result, we did not have any significant concentrations of credit risk at December 31, 2023. In addition, there were no customers that accounted for more than 10% of our revenues for the year ended December 31, 2023.

XML

Summary of Significant Accounting Policies (Tables)

12 Months Ended

Dec. 31, 2023

Accounting Policies [Abstract]

Schedule of inventory

Our inventories as of December 31 consisted of:

(in millions)	2023		2022
Materials and supplies	$	186.6	$	150.6
Fossil fuel	74.5		62.7
Natural gas in storage	49.5		79.6
Total	$	310.6	$	292.9

Schedule of AFUDC amounts

We recorded the following AFUDC for the years ended December 31:

(in millions)	2023		2022		2021
AFUDC-Debt	$	13.0	$	6.9	$	2.9
AFUDC-Equity	41.0		18.8		7.9

Schedule of assumptions used to estimate the fair value of stock options granted

The following table shows the estimated weighted-average fair value per stock option granted to our employees along with the weighted-average assumptions used in the valuation models:

	2023			2022			2021
Stock options granted	30,495			51,511			60,108
Estimated weighted-average fair value per stock option	$	19.58		$	14.71		$	13.20
Assumptions used to value the options:
Risk-free interest rate	3.8% – 4.8%			0.2% – 1.6%			0.1% – 0.9%
Dividend yield	3.2		%	3.2		%	2.9		%
Expected volatility	22.0		%	21.0		%	21.0		%
Expected life (years)	8.3			8.7			8.7

XML

Related Parties (Tables)

12 Months Ended

Dec. 31, 2023

Related Party Transactions [Abstract]

Schedule of receivables and payables with ATC

Our balance sheets included the following receivables and payables for services provided to or received from ATC:

(in millions)	December 31, 2023		December 31, 2022
Accounts receivable
Services provided to ATC	$	0.9	$	0.7
Amounts due from ATC for transmission infrastructure upgrades (1)	39.5		23.3
Accounts payable
Services received from ATC	36.7		20.0

(1)     The transmission infrastructure upgrades were primarily related to the construction of our renewable energy projects.

Schedule of activity associated with related party transactions

The following table shows activity associated with our related party transactions for the years ended December 31:

(in millions)	2023		2022		2021
Transactions with WPS
Natural gas related purchases from WPS (1)	$	1.3	$	3.3	$	2.9
Charges to WPS for services and other items (2)	16.2		13.3		11.8
Charges from WPS for services and other items (2)	11.3		10.7		9.4
Transactions with WG
Natural gas related purchases from WG (1)	19.7		6.2		5.9
Natural gas related sales to WG (1)	0.3		1.3		0.3
Charges to WG for services and other items (2)	38.3		39.5		40.4
Charges from WG for services and other items (2)	27.9		29.8		29.7
Transactions with UMERC
Charges to UMERC for services and other items (2)	11.8		13.7		10.5
Charges from UMERC for services and other items (2)	2.0		1.2		1.2
Transactions with Bluewater
Charges from Bluewater for storage service fees (3)	17.2		14.8		13.6
Charges from Bluewater for other operating fees (3)	4.1		3.3		1.4
Natural gas related sales to Bluewater (1)	2.8		2.7		2.6
Charges to Bluewater for services and other items (2)	2.7		2.7		3.0
Transactions with We Power
Lease payments and other lease-related charges from We Power (4)	422.0		412.6		406.0
Charges to We Power for services and other items (2)	7.8		4.2		6.7
Transactions with WBS
Charges to WBS for services and other items (2)	41.1		49.5		67.8		(5)
Charges from WBS for services and other items (2)	113.3		123.1		123.8
Transactions with ATC
Charges to ATC for services and construction	8.1		9.3		14.9
Charges from ATC for network transmission services	248.8		239.3		240.4
Net refund (payment) from (to) ATC related to FERC ROE orders	—		(0.1)		5.1

(1)    Includes amounts related to the purchase or sale of natural gas and/or pipeline capacity.

(2)    Includes amounts charged for services, pass through costs, asset and liability transfers, and other items in accordance with the approved AIA.

(3)    We have a long-term service agreement with a wholly owned subsidiary of Bluewater that was previously approved by the PSCW. Bluewater owns natural gas storage facilities in Michigan and provides a portion of our current storage needs.

(4)    We make lease payments to We Power for PWGS Units 1 and 2 and ERGS Units 1 and 2. See Note 15, Leases, for more information.

(5)     Includes $11.3 million for the transfer of certain software assets to WBS.

XML

Operating Revenues (Tables) - Utility

12 Months Ended

Dec. 31, 2023

Disaggregation of Operating Revenues

Operating revenues disaggregated by revenue source

The following tables present our operating revenues disaggregated by revenue source for our utility segment. We do not have any revenues associated with our other segment. We disaggregate revenues into categories that depict how the nature, amount, timing, and uncertainty of revenues and cash flows are affected by economic factors. Revenues are further disaggregated by electric and natural gas operations and then by customer class. Each customer class within our electric and natural gas operations has different expectations of service, energy and demand requirements, and can be impacted differently by regulatory activities within their jurisdictions.

	Year Ended December 31
(in millions)	2023		2022		2021
Wisconsin Electric Power Company
Electric utility	$	3,540.2	$	3,448.7	$	3,171.6
Natural gas utility	489.8		606.8		474.2
Total revenues from contracts with customers	4,030.0		4,055.5		3,645.8
Other operating revenues	15.0		14.8		18.7
Total operating revenues	$	4,045.0	$	4,070.3	$	3,664.5

Revenues from contracts with customers | Electric

Disaggregation of Operating Revenues

Operating revenues disaggregated by revenue source

The following table disaggregates electric utility operating revenues into customer class:

	Year Ended December 31
(in millions)	2023		2022		2021
Residential	$	1,480.6	$	1,376.3	$	1,306.2
Small commercial and industrial	1,177.2		1,095.0		1,019.7
Large commercial and industrial	616.0		629.1		568.6
Other	21.1		20.4		20.2
Total retail revenues	3,294.9		3,120.8		2,914.7
Wholesale	40.9		58.4		71.0
Resale	173.7		224.3		148.2
Steam	25.2		28.4		28.7
Other utility revenues	5.5		16.8		9.0
Total electric utility operating revenues	$	3,540.2	$	3,448.7	$	3,171.6

Revenues from contracts with customers | Natural gas

Disaggregation of Operating Revenues

Operating revenues disaggregated by revenue source

The following table disaggregates natural gas utility operating revenues into customer class:

	Year Ended December 31
(in millions)	2023		2022		2021
Residential	$	323.3	$	397.8	$	309.1
Commercial and industrial	148.2		193.7		141.9
Total retail revenues	471.5		591.5		451.0
Transportation	21.6		17.8		17.3
Other utility revenues (1)	(3.3)		(2.5)		5.9
Total natural gas utility operating revenues	$	489.8	$	606.8	$	474.2

(1)    Includes the revenues subject to our purchased gas recovery mechanism, which fluctuate based on actual natural gas costs incurred, compared with the recovery of natural gas costs that were anticipated in rates.

Other operating revenues

Disaggregation of Operating Revenues

Operating revenues disaggregated by revenue source

Other operating revenues consist of the following:

	Year Ended December 31
(in millions)	2023		2022		2021
Late payment charges	$	12.2	$	12.1	$	13.3
Rental revenues	2.5		2.5		3.0
Alternative revenues	0.3		0.2		2.4
Total other operating revenues	$	15.0	$	14.8	$	18.7

XML

Credit Losses (Tables)

12 Months Ended

Dec. 31, 2023

Credit Loss [Abstract]

Schedule of gross receivables and related allowances for credit losses

The table below shows our gross third-party receivable balances and related allowance for credit losses.

(in millions)	December 31, 2023			December 31, 2022
Accounts receivable and unbilled revenues	$	617.5		$	632.3
Allowance for credit losses	44.5			49.7
Accounts receivable and unbilled revenues, net (1)	$	573.0		$	582.6
Total accounts receivable, net – past due greater than 90 days (1)	$	37.2		$	35.8
Past due greater than 90 days – collection risk mitigated by regulatory mechanisms (1)	94.1		%	97.5		%

(1)    Our exposure to credit losses for certain regulated utility customers is mitigated by a regulatory mechanism we have in place. Specifically, our residential tariffs include a mechanism for cost recovery or refund of uncollectible expense based on the difference between actual uncollectible write-offs and the amounts recovered in rates. As a result, at December 31, 2023, $342.5 million, or 59.8%, of our net accounts receivable and unbilled revenues balance had regulatory protections in place to mitigate the exposure to credit losses.

Rollforward of the allowances for credit losses

A rollforward of the allowance for credit losses is included below:

	Year Ended December 31
(in millions)	2023		2022		2021
Balance at January 1	$	49.7	$	51.4	$	59.3
Provision for credit losses	23.8		27.3		24.8
Provision for credit losses deferred for future recovery or refund	45.7		34.0		(0.3)
Write-offs charged against the allowance	(94.1)		(83.4)		(47.6)
Recoveries of amounts previously written off	19.4		20.4		15.2
Balance at December 31	$	44.5	$	49.7	$	51.4

XML

Regulatory Assets and Liabilities (Tables)

12 Months Ended

Dec. 31, 2023

Regulatory Assets and Liabilities Disclosure [Abstract]

Schedule of regulatory assets

The following regulatory assets were reflected on our balance sheets as of December 31:

(in millions)	2023		2022		See Note
Regulatory assets (1) (2)
Finance leases	$	1,109.7	$	1,072.0	15
Plant retirement related items	595.5		632.7
Income tax related items	373.1		382.1		16
Pension and OPEB costs (3)	348.9		337.2		19, 24
SSR (4)	113.2		123.5
Securitization	85.9		92.4		21
Uncollectible expense	62.1		16.4		6
Derivatives	45.2		40.3		1(p)
AROs	41.2		41.1		1(k), 10
Energy efficiency programs (5)	23.3		17.7
We Power generation (6)	4.7		21.6
Other, net	57.9		40.5
Total regulatory assets	$	2,860.7	$	2,817.5

(1)    Based on prior and current rate treatment, we believe it is probable that we will continue to recover from customers the regulatory assets in this table. In accordance with GAAP, our regulatory assets do not include the allowance for ROE that is capitalized for regulatory purposes. This allowance was $16.5 million and $14.7 million at December 31, 2023 and 2022, respectively.

(2)    As of December 31, 2023, we had $1.9 million of regulatory assets not earning a return, $4.7 million of regulatory assets earning a return based on short-term interest rates, and $129.7 million of regulatory assets earning a return based on long-term interest rates. The regulatory assets not earning a return relate to certain environmental remediation costs. The other regulatory assets in the table either earn a return at our weighted average cost of capital or the cash has not yet been expended, in which case the regulatory assets are offset by liabilities.

(3)    Primarily represents the unrecognized future pension and OPEB costs related to our defined benefit pension and OPEB plans. We are authorized recovery of these regulatory assets over the average remaining service life of each plan.

(4)    This regulatory asset relates to our 2014 announcement to retire the PIPP. Despite our intent to retire the PIPP, MISO designated the PIPP as an SSR, which meant the PIPP's operation was necessary for reliability, and the plant could not be shut down until new generation or transmission facilities were built. In December 2014, the PSCW authorized escrow accounting for our SSR revenues because of the fluctuations in the actual revenues we received under the PIPP SSR agreements. The rate order we received from the PSCW in December 2019 authorized recovery of this SSR regulatory asset over a 15-year period that began on January 1, 2020.

(5)    Represents amounts recoverable from customers related to programs designed to meet energy efficiency standards.

(6)    Represents amounts recoverable from customers related to our costs of the generating units leased from We Power, including subsequent capital additions.

Schedule of regulatory liabilities

The following regulatory liabilities were reflected on our balance sheets as of December 31:

(in millions)	2023		2022		See Note
Regulatory liabilities
Removal costs (1)	$	758.9	$	718.1
Income tax related items	683.5		716.1		16
Pension and OPEB benefits (2)	124.0		144.4		19, 24
Electric transmission costs (3)	23.9		0.2
Energy efficiency programs (4)	10.6		1.0
Derivatives	4.5		39.1		1(p)
Other, net	31.3		19.9
Total regulatory liabilities	$	1,636.7	$	1,638.8
Balance sheet presentation
Other current liabilities	$	5.3	$	1.4
Regulatory liabilities	1,631.4		1,637.4
Total regulatory liabilities	$	1,636.7	$	1,638.8

(1)    Represents amounts collected from customers to cover the future cost of property, plant, and equipment removals that are not legally required. Legal obligations related to the removal of property, plant, and equipment are recorded as AROs. See Note 10, Asset Retirement Obligations, for more information on our legal obligations.

(2)    Primarily represents the unrecognized future pension and OPEB benefits related to our defined benefit pension and OPEB plans. We will amortize these regulatory liabilities into net periodic benefit cost over the average remaining service life of each plan.

(3)    In accordance with the PSCW's approval of escrow accounting for our ATC and MISO network transmission expenses, we defer as a regulatory asset or liability the difference between actual transmission costs and those included in rates until recovery or refund is authorized in a future rate proceeding.

(4)    Represents amounts refundable to customers related to programs designed to meet energy efficiency standards.

XML

Property, Plant, and Equipment (Tables)

12 Months Ended

Dec. 31, 2023

Property, Plant and Equipment [Abstract]

Property, Plant and Equipment -Balances

Property, plant, and equipment consisted of the following at December 31:

(in millions)	2023		2022
Electric – generation	$	2,721.3	$	2,200.0
Electric – distribution	6,116.7		5,822.4
Natural gas – distribution, storage, and transmission	2,059.4		1,757.0
Property, plant, and equipment to be retired	783.7		812.5
Other	1,087.0		1,044.9
Less: Accumulated depreciation	3,530.3		3,213.4
Net	9,237.8		8,423.4
CWIP	624.7		556.1
Net utility and non-utility property, plant, and equipment	9,862.5		8,979.5
Property under finance leases	3,206.8		3,248.8
Less: Accumulated amortization	1,483.8		1,509.7
Net leased facilities	1,723.0		1,739.1
Total property, plant, and equipment	$	11,585.5	$	10,718.6

Schedule of activity related to severance liability

Activity related to these severance liabilities for the years ended December 31 was as follows:

(in millions)	2023		2022		2021
Severance liability at January 1	$	13.5	$	3.3	$	0.7
Severance expense	1.6		10.2		3.0
Severance payments	—		—		(0.4)
Total severance liability at December 31	$	15.1	$	13.5	$	3.3

XML

Jointly Owned Utility Facilities (Tables)

12 Months Ended

Dec. 31, 2023

Jointly Owned Utility Plant, Net Ownership Amount [Abstract]

Schedule of jointly owned utility facilities

Information related to jointly owned utility facilities at December 31, 2023 was as follows:

Jointly-Owned Utility Facilities	Ownership		Share of Capacity (MW)	In-Service /Acquisition Date	Operating Owner	Property, Plant, and Equipment		Accumulated Depreciation		CWIP
(in millions, except for percentages and MW)
West Riverside (1) (3)	13.8	%	84.9	2023	WE	$	108.7	$	(11.3)	$	0.9
Badger Hollow II (2)	66.7	%	100.0	2023	WE	170.1		(0.3)		0.1
Weston RICE units (1)	50.0	%	65.0	2023	WPS	92.4		(1.3)		—
Whitewater (1) (4)	50.0	%	121.4	2023	WE	125.7		(93.6)		0.3

(1)    Capacity is based on rated capacity, which is the net power output under average operating conditions with equipment in an average state of repair as of a given month in a given year. Values are primarily based on the net dependable expected capacity ratings for summer 2024 established by tests and may change slightly from year to year. The summer period is the most relevant for capacity planning purposes. This is a result of continually reaching demand peaks in the summer months, primarily due to air conditioning demand.

(2)     Capacity for solar generating facilities is based on nameplate capacity, which is the maximum output that a generator should produce at continuous full power.

(3)    We acquired our ownership interest in June 2023. In September 2023, WPS filed a request with the PSCW to exercise a second option to acquire an additional 100 MWs of West Riverside's nameplate capacity. WPS subsequently filed for approval to assign its ownership interest pursuant to this second option to us. See Note 2, Acquisitions, for more information.

(4)    Effective January 1, 2023, we, along with WPS, completed the acquisition of Whitewater. See Note 2, Acquisitions, for more information.

XML

Asset Retirement Obligations (Tables)

12 Months Ended

Dec. 31, 2023

Asset Retirement Obligation Disclosure [Abstract]

Schedule of changes to asset retirement obligations

The following table shows changes to our AROs during the years ended December 31:

(in millions)	2023			2022		2021
Balance as of January 1	$	71.7		$	70.8	$	54.5
Accretion	1.8			1.8		1.7
Additions	4.4		(1)	—		—
Revisions to estimated cash flows	(4.5)		(2)	0.3		17.3		(3)
Liabilities settled	(0.3)			(1.2)		(2.7)
Balance as of December 31	$	73.1		$	71.7	$	70.8

(1)    AROs increased primarily as a result of AROs being recorded for the legal requirement to dismantle, at retirement, the Badger Hollow II solar generation project.

(2)    AROs decreased primarily due to revisions made to removal estimates for fly ash landfills and changes in settlement timing of electric substation asbestos liabilities.

(3)     AROs increased primarily due to revisions made to removal estimates for Blue Sky, Glacier Hills, and Montfort.

XML

Common Equity (Tables)

12 Months Ended

Dec. 31, 2023

Stockholders' Equity Note [Abstract]

Schedule of stock-based compensation expense and related tax benefit recognized in income

The following table summarizes our pre-tax stock-based compensation expense, including amounts allocated from WBS, and the related tax benefit recognized in income for the years ended December 31:

(in millions)	2023			2022		2021
Stock options	$	1.9		$	2.4	$	2.3
Restricted stock	2.3			2.3		2.2
Performance units	(0.9)		(1)	8.5		1.7
Stock-based compensation expense	$	3.3		$	13.2	$	6.2
Related tax benefit	$	0.9		$	3.6	$	1.7

(1)    The reduction in expense was due to a decrease in the fair value of the outstanding performance units.

Schedule of stock option activity

The following is a summary of our employees' WEC Energy Group stock option activity during 2023:

Stock Options	Number of Options	Weighted-Average Exercise Price		Weighted-Average Remaining Contractual Life (in years)	Aggregate Intrinsic Value (in millions)
Outstanding as of January 1, 2023	475,509	$	70.63
Granted	30,495	93.69
Exercised	(57,704)	43.70
Outstanding as of December 31, 2023	448,300	75.67		5.1	$	5.6
Exercisable as of December 31, 2023	332,592	69.45		4.2	$	5.6

Schedule of restricted stock activity

The following is a summary of our employees' WEC Energy Group restricted stock activity during 2023:

Restricted Shares	Number of Shares	Weighted-Average Grant Date Fair Value
Outstanding and unvested as of January 1, 2023	7,208	$	93.97
Granted	4,544	93.69
Released	(3,358)	93.21
Forfeited	(223)	94.13
Outstanding and unvested as of December 31, 2023	8,171	94.12

XML

Preferred Stock (Tables)

12 Months Ended

Dec. 31, 2023

Class of Stock Disclosures [Abstract]

Schedule of preferred stock by class

The following table shows preferred stock authorized and outstanding at December 31, 2023 and 2022:

(in millions, except share and per share amounts)	Shares Authorized	Shares Outstanding	Redemption Price Per Share		Total
$100 par value, Six Per Cent. Preferred Stock	45,000	44,498	$	—	$	4.4
$100 par value, Serial Preferred Stock 3.60% Series	2,286,500	260,000	101		26.0
$25 par value, Serial Preferred Stock	5,000,000	—	—		—
Total					$	30.4

XML

Short-Term Debt and Lines of Credit (Tables)

12 Months Ended

Dec. 31, 2023

Short-Term Debt [Abstract]

Short-term debt balances and their corresponding weighted-average interest rates

The following table shows our short-term borrowings and their corresponding weighted-average interest rates as of December 31:

(in millions, except percentages)	2023			2022
Commercial paper
Amount outstanding at December 31	$	360.8		$	460.7
Average interest rate on amounts outstanding at December 31	5.48		%	4.59		%

Schedule of Revolving Credit Facilities

The information in the table below relates to our revolving credit facility used to support our commercial paper borrowing program, including remaining available capacity under this facility as of December 31:

(in millions)	Maturity	2023
Revolving credit facility	September 2026	$	500.0
Less:
Letters of credit issued inside credit facility		1.0
Commercial paper outstanding		360.8
Available capacity under existing agreement		$	138.2

XML

Long-Term Debt (Tables)

12 Months Ended

Dec. 31, 2023

Debt Disclosure [Abstract]

Schedule of long-term debt instruments

The following table is a summary of our long-term debt outstanding as of December 31:

(in millions)	Interest Rate	Year Due	2023		2022
WE Debentures (unsecured)	2.05%	2024	$	300.0	$	300.0
	3.10%	2025	250.0		250.0
	6.50%	2028	150.0		150.0
	1.70%	2028	300.0		300.0
	4.75%	2032	500.0		500.0
	5.625%	2033	335.0		335.0
	5.70%	2036	300.0		300.0
	3.65%	2042	250.0		250.0
	4.25%	2044	250.0		250.0
	4.30%	2045	250.0		250.0
	4.30%	2048	300.0		300.0
	6.875%	2095	100.0		100.0
WEPCo Environmental Trust (secured, nonrecourse) (1) (2)	1.578%	2024-2035	97.0		105.9
Total			3,382.0		3,390.9
Unamortized debt issuance costs			(13.0)		(14.9)
Unamortized discount, net			(14.6)		(15.6)
Total long-term debt, including current portion			3,354.4		3,360.4
Current portion of long-term debt			(309.0)		(8.9)
Total long-term debt			$	3,045.4	$	3,351.5

(1)    WEPCo Environmental Trust’s ETBs are secured by a pledge of and lien on environmental control property, which includes the right to impose, collect and receive a non-bypassable environmental control charge paid by all of our retail electric distribution customers, the right to obtain true-up adjustments of the environmental control charge, and all revenues or other proceeds arising from those rights and interests. See Note 21, Variable Interest Entities, for more information.

(2)    The long-term debt of WEPCo Environmental Trust requires periodic principal payments.

Schedule of future maturities of long-term debt outstanding

The following table shows the future maturities of our long-term debt outstanding as of December 31, 2023:

(in millions)
2024	$	309.0
2025	259.2
2026	9.3
2027	9.5
2028	459.6
Thereafter	2,335.4
Total	$	3,382.0

XML

Leases (Tables)

12 Months Ended

Dec. 31, 2023

Leases [Abstract]

Schedule of lease expense and supplemental cash flow information for leases

The components of lease expense and supplemental cash flow information related to our leases for the years ended December 31 are as follows:

(in millions)	2023			2022			2021
Finance lease expense
Amortization of right of use assets (1)	$	77.5		$	74.2		$	68.1
Interest on lease liabilities (2)	329.5			334.3			341.2
Operating lease expense (3)	1.6			1.8			1.4
Total lease expense	$	408.6		$	410.3		$	410.7
Other information
Cash paid for amounts included in the measurement of lease liabilities
Operating cash flows for finance leases	$	329.5		$	334.3		$	341.2
Operating cash flows for operating leases	1.6			1.8			1.4
Financing cash flows for finance leases	77.0			73.6			67.5
Non-cash activities:
Right of use assets obtained in exchange for finance lease liabilities (4)	$	136.5		$	60.0		$	52.7
Right of use assets obtained in exchange for operating lease liabilities	2.3			—			0.3
Weighted-average remaining lease term – finance leases	16.2 years			16.5 years			16.9 years
Weighted-average remaining lease term – operating leases	24.9 years			27.0 years			28.5 years
Weighted-average discount rate – finance leases (5)	13.4		%	13.6		%	13.8		%
Weighted average discount rate – operating leases (5)	4.8		%	4.5		%	4.5		%

(1)    Amortization of right of use assets was included as a component of depreciation and amortization expense.

(2)    Interest on lease liabilities was included as a component of interest expense.

(3)    Operating lease expense was included as a component of other operation and maintenance expense.

(4)    Amounts are net of any reductions to right of use assets and finance lease liabilities resulting from remeasurements.

(5)    Because our operating leases and our power purchase commitment and solar land leases accounted for as finance leases do not provide an implicit rate of return, we used the fully collateralized incremental borrowing rates based upon information available for similarly rated companies in determining the present value of lease payments. For the PWGS and ERGS units that meet the definition of a finance lease, the rate implicit in the lease was readily determinable.

Schedule of finance and operating lease right of use assets and obligations

The following table summarizes our finance and operating lease right of use assets and obligations at December 31:

(in millions)	2023		2022		Balance Sheet Location
Right of use assets
Operating lease right of use assets, net	$	10.2	$	8.4	Other long-term assets
Finance lease right of use assets, net
Power purchase commitment (1)	$	—	$	38.3
PWGS	268.6		297.1
ERGS	1,362.0		1,335.8
Land leases – utility solar generation	92.4		67.9
Total finance lease right of use assets, net (2)	$	1,723.0	$	1,739.1	Property, plant, and equipment, net
Lease obligations
Current operating lease liabilities	$	0.8	$	0.6	Other current liabilities
Long-term operating lease liabilities	$	9.4	$	7.8	Other long-term liabilities
Current finance lease liabilities
Power purchase commitment (1)	$	—	$	36.3
PWGS	42.9		37.8
ERGS	44.9		38.2
Total current finance lease liabilities	$	87.8	$	112.3	Current portion of finance lease obligations
Long-term finance lease liabilities
PWGS	$	474.8	$	512.2
ERGS	2,177.8		2,118.8
Land leases – utility solar generation	99.6		71.3
Total long-term finance lease liabilities	$	2,752.2	$	2,702.3	Finance lease obligations

(1)    Effective January 1, 2023, we and WPS closed on the acquisition of Whitewater. See discussion above for more information.

(2)    Amounts are net of accumulated amortization of $1,483.8 million and $1,509.7 million at December 31, 2023 and 2022, respectively.

Schedule of future minimum lease payments for operating and finance leases

Future minimum lease payments under our operating and finance leases and the present value of our net minimum lease payments as of December 31, 2023, were as follows:

(in millions)	Total Operating Leases		PWGS		ERGS		Land Leases - Utility Solar Generation		Total Finance Leases
2024	$	1.3	$	102.8	$	314.0	$	3.4	$	420.2
2025	1.0		102.5		313.9		4.5		420.9
2026	1.0		102.4		313.9		4.6		420.9
2027	0.7		102.2		313.8		4.6		420.6
2028	0.5		102.2		313.7		4.7		420.6
Thereafter	13.9		302.0		3,614.2		347.5		4,263.7
Total minimum lease payments	18.4		814.1		5,183.5		369.3		6,366.9
Less: Interest	(8.2)		(296.4)		(2,960.8)		(269.7)		(3,526.9)
Present value of minimum lease payments	10.2		517.7		2,222.7		99.6		2,840.0
Less: Short-term lease liabilities	(0.8)		(42.9)		(44.9)		—		(87.8)
Long-term lease liabilities	$	9.4	$	474.8	$	2,177.8	$	99.6	$	2,752.2

XML

Income Taxes (Tables)

12 Months Ended

Dec. 31, 2023

Income Tax Disclosure [Abstract]

Summary of income tax expense

The following table is a summary of income tax expense for each of the years ended December 31:

(in millions)	2023		2022		2021
Current tax expense	$	122.0	$	81.0	$	90.3
Deferred income taxes, net	26.2		53.6		(30.7)
ITCs	(5.5)		(1.5)		(1.5)
Total income tax expense	$	142.7	$	133.1	$	58.1

Statutory rate reconciliation

The provision for income taxes for each of the years ended December 31 differs from the amount of income tax determined by applying the applicable United States statutory federal income tax rate to income before income taxes as a result of the following:

	2023				2022				2021
(in millions)	Amount		Effective Tax Rate		Amount		Effective Tax Rate		Amount		Effective Tax Rate
Statutory federal income tax	$	130.9	21.0	%	$	111.2	21.0	%	$	92.3	21.0	%
State income taxes net of federal tax benefit	37.4		6.0	%	33.1		6.3	%	28.2		6.4	%
Federal excess deferred tax amortization (1)	(20.8)		(3.3)	%	(23.2)		(4.4)	%	(23.2)		(5.3)	%
PTCs	(11.6)		(1.9)	%	(2.3)		(0.4)	%	(6.8)		(1.5)	%
AFUDC-Equity	(8.6)		(1.4)	%	(3.9)		(0.7)	%	(1.7)		(0.4)	%
Domestic production activities deferral	6.3		1.0	%	6.3		1.1	%	6.3		1.4	%
Federal excess deferred tax amortization – Wisconsin unprotected (2)	5.3		0.9	%	5.3		1.0	%	(42.7)		(9.7)	%
Other, net	3.8		0.6	%	6.6		1.2	%	5.7		1.3	%
Total income tax expense	$	142.7	22.9	%	$	133.1	25.1	%	$	58.1	13.2	%

(1)    The Tax Legislation required us to remeasure our deferred income taxes and we began to amortize the resulting excess protected deferred income taxes beginning in 2018 in accordance with normalization requirements. The decrease in income tax expense related to the amortization of the deferred tax benefits is offset by a decrease in revenue as the benefits are returned to customers, resulting in no impact on net income.

(2)    In accordance with the rate order received from the PSCW in December 2019, the majority of our net unprotected deferred tax benefits related to electric operations were amortized to reduce near-term impacts to our customers over a period of two years, beginning with 2020. Consistent with the same rate order, the net unprotected tax expense related to gas and steam operations continues to be amortized over a period of four years, which began in 2020. The increase (decrease) in income tax expense related to the amortization of the deferred taxes is offset by an increase (decrease) in revenue as amounts are either collected from or returned to customers, resulting in no impact on net income.

Components of deferred income taxes

The components of deferred income taxes as of December 31 were as follows:

(in millions)	2023		2022
Deferred tax assets
Tax gross up – regulatory items	$	103.4	$	110.3
Deferred revenues	103.9		106.5
Future tax benefits	7.1		10.1
Other	53.6		60.2
Total deferred tax assets	$	268.0	$	287.1
Deferred tax liabilities
Property-related	$	1,430.4	$	1,399.0
Deferred costs – plant retirements	186.2		198.0
Employee benefits and compensation	60.6		68.2
Deferred costs – SSR	37.5		40.9
Other	66.8		48.3
Total deferred tax liabilities	1,781.5		1,754.4
Deferred tax liability, net	$	1,513.5	$	1,467.3

Components of deferred tax assets associated with federal tax benefit carryforwards

The components of net deferred tax assets associated with federal tax benefit carryforwards as of December 31, 2023 and 2022 are summarized in the tables below:

2023 (in millions)	Gross Value		Deferred Tax Effect		Earliest Year of Expiration
Future tax benefits as of December 31, 2023
Federal tax credit	$	—	$	7.1	2042
Balance as of December 31, 2023	$	—	$	7.1

2022 (in millions)	Gross Value		Deferred Tax Effect		Earliest Year of Expiration
Future tax benefits as of December 31, 2022
Federal tax credit	$	—	$	10.1	2041
Balance as of December 31, 2022	$	—	$	10.1

XML

Fair Value Measurements (Tables)

12 Months Ended

Dec. 31, 2023

Fair Value Disclosures [Abstract]

Schedule of fair value of assets and liabilities measured on a recurring basis categorized by level within the fair value hierarchy

The following tables summarize our financial assets and liabilities that were accounted for at fair value on a recurring basis, categorized by level within the fair value hierarchy:

	December 31, 2023
(in millions)	Level 1		Level 2		Level 3		Total
Derivative assets
Natural gas contracts	$	0.9	$	1.3	$	—	$	2.2
FTRs	—		—		2.5		2.5
Total derivative assets	$	0.9	$	1.3	$	2.5	$	4.7
Derivative liabilities
Natural gas contracts	$	16.1	$	3.1	$	—	$	19.2
Coal contracts	—		19.3		—		19.3
Total derivative liabilities	$	16.1	$	22.4	$	—	$	38.5

	December 31, 2022
(in millions)	Level 1		Level 2		Level 3		Total
Derivative assets
Natural gas contracts	$	1.6	$	2.5	$	—	$	4.1
FTRs	—		—		2.0		2.0
Coal contracts	—		32.7		—		32.7
Total derivative assets	$	1.6	$	35.2	$	2.0	$	38.8
Derivative liabilities
Natural gas contracts	$	29.3	$	0.7	$	—	$	30.0

Reconcilation of changes in fair value of items categorized as level 3 measurements

The following table summarizes the changes to derivatives classified as Level 3 in the fair value hierarchy at December 31:

(in millions)	2023		2022		2021
Balance at the beginning of the period	$	2.0	$	1.0	$	1.1
Purchases	8.1		7.6		3.1
Settlements	(7.6)		(6.6)		(3.2)
Balance at the end of the period	$	2.5	$	2.0	$	1.0

Schedule of carrying value and fair value of financial instruments not recorded at fair value

The following table shows the financial instruments included on our balance sheets that are not recorded at fair value:

	December 31, 2023				December 31, 2022
(in millions)	Carrying Amount		Fair Value		Carrying Amount		Fair Value
Preferred stock	$	30.4	$	21.4	$	30.4	$	22.7
Long-term debt, including current portion	3,354.4		3,255.4		3,360.4		3,143.2

XML

Derivative Instruments (Tables)

12 Months Ended

Dec. 31, 2023

Derivative Instruments and Hedging Activities Disclosure [Abstract]

Schedule of derivative assets and liabilities

The following table shows our derivative assets and derivative liabilities. None of the derivatives shown below were designated as hedging instruments.

	December 31, 2023				December 31, 2022
(in millions)	Derivative Assets		Derivative Liabilities		Derivative Assets		Derivative Liabilities
Current
Natural gas contracts	$	2.2	$	18.6	$	4.1	$	28.8
FTRs	2.5		—		2.0		—
Coal contracts	—		10.2		17.6		—
Total current	4.7		28.8		23.7		28.8
Long-term
Natural gas contracts	—		0.6		—		1.2
Coal contracts	—		9.1		15.1		—
Total long-term	—		9.7		15.1		1.2
Total	$	4.7	$	38.5	$	38.8	$	30.0

Schedule of estimated notional sales volumes and realized gains (losses)

Our estimated notional sales volumes and realized gains and losses were as follows for the years ended:

	December 31, 2023			December 31, 2022			December 31, 2021
(in millions)	Volumes	Gains (Losses)		Volumes	Gains		Volumes	Gains
Natural gas contracts	68.5 Dth	$	(102.2)	59.7 Dth	$	86.6	69.2 Dth	$	50.8
FTRs	20.4 MWh	14.5		18.9 MWh	8.1		21.0 MWh	8.7
Total		$	(87.7)		$	94.7		$	59.5

Schedule of net derivative instruments

The following table shows derivative assets and derivative liabilities if derivative instruments by counterparty were presented net on our balance sheets:

	December 31, 2023					December 31, 2022
(in millions)	Derivative Assets		Derivative Liabilities			Derivative Assets		Derivative Liabilities
Gross amount recognized on the balance sheet	$	4.7	$	38.5		$	38.8	$	30.0
Gross amount not offset on the balance sheet	(1.3)		(16.5)		(1)	(1.8)		(29.5)		(2)
Net amount	$	3.4	$	22.0		$	37.0	$	0.5

(1)      Includes cash collateral posted of $15.2 million.

(2)      Includes cash collateral posted of $27.7 million.

XML

Employee Benefits (Tables)

12 Months Ended

Dec. 31, 2023

Retirement Benefits [Abstract]

Reconciliation of the changes in the plans' benefit obligations and fair value of assets

The following tables provide a reconciliation of the changes in our share of the plans' benefit obligations and fair value of assets:

	Pension Benefits				OPEB Benefits
(in millions)	2023		2022		2023		2022
Change in benefit obligation
Obligation at January 1	$	894.9	$	1,144.0	$	144.6	$	190.6
Service cost	10.3		13.4		2.6		3.9
Interest cost	47.1		32.6		7.7		5.6
Participant contributions	—		—		5.6		6.6
Net transfer from/to affiliates	(1.2)		4.7		(0.4)		—
Actuarial (gain) loss	29.1		(211.3)		19.5		(46.9)
Benefit payments	(79.4)		(88.5)		(18.7)		(19.0)
Federal subsidy on benefits paid	N/A		N/A		1.3		1.2
Transfer	—		—		1.2		2.6
Obligation at December 31	$	900.8	$	894.9	$	163.4	$	144.6
Change in fair value of plan assets
Fair value at January 1	$	940.7	$	1,136.9	$	211.3	$	255.7
Actual return on plan assets	68.9		(115.8)		17.7		(32.6)
Employer contributions net of plan transfer (1)	3.2		3.8		(42.9)		0.1
Participant contributions	—		—		5.6		6.6
Net transfer from/to affiliates	(1.2)		4.3		(0.2)		0.5
Benefit payments	(79.4)		(88.5)		(18.7)		(19.0)
Fair value at December 31	$	932.2	$	940.7	$	172.8	$	211.3
Funded status at December 31	$	31.4	$	45.8	$	9.4	$	66.7

(1)    Employer contribution includes a $43.0 million transfer out of the WEC Energy Group Retiree Welfare Plan, in 2023, associated with the overfunded position of this plan.

Amounts recognized on the balance sheets at December 31 related to the funded status of the benefit plans

The amounts recognized on our balance sheets at December 31 related to the funded status of the benefit plans were as follows:

	Pension Benefits				OPEB Benefits
(in millions)	2023		2022		2023		2022
Pension and OPEB assets	$	61.6	$	76.6	$	9.4	$	66.7
Other long-term liabilities	30.2		30.8		—		—
Total net assets	$	31.4	$	45.8	$	9.4	$	66.7

Information for pension plans with an accumulated benefit obligation in excess of plan assets

The following table shows information for the pension plans with an accumulated benefit obligation in excess of plan assets. There were no plan assets related to these pension plans. Amounts presented are as of December 31:

(in millions)	2023		2022
Accumulated benefit obligation	$	30.0	$	30.6

Information for pension plans with a projected benefit obligation in excess of plan assets

The following table shows information for pension plans with a projected benefit obligation in excess of plan assets. There were no plan assets related to these pension plans. Amounts presented are as of December 31:

(in millions)	2023		2022
Projected benefit obligation	$	30.2	$	30.8

Amounts that had not yet been recognized in the entity's net periodic benefit cost

The following table shows the amounts that had not yet been recognized in our net periodic benefit cost as of December 31:

	Pension Benefits				OPEB Benefits
(in millions)	2023		2022		2023		2022
Net regulatory assets (liabilities)
Net actuarial loss (gain)	$	342.1	$	326.7	$	(89.1)	$	(113.0)
Prior service credits	(1.9)		(2.0)		(0.4)		(1.3)
Total	$	340.2	$	324.7	$	(89.5)	$	(114.3)

Schedule of the components of net periodic benefit cost

The components of net periodic benefit cost (credit) (including amounts capitalized to our balance sheets) for the years ended December 31 were as follows:

	Pension Benefits						OPEB Benefits
(in millions)	2023		2022		2021		2023		2022		2021
Service cost	$	10.3	$	13.4	$	14.4	$	2.6	$	3.9	$	4.3
Interest cost	47.1		32.6		31.1		7.7		5.6		5.3
Expected return on plan assets	(64.3)		(71.4)		(70.3)		(13.4)		(17.7)		(16.9)
Amortization of prior service credit	(0.1)		(0.1)		(0.1)		(0.9)		(1.3)		(1.2)
Amortization of net actuarial loss (gain)	9.2		29.8		41.9		(8.7)		(12.1)		(10.9)
Net periodic benefit cost (credit)	$	2.2	$	4.3	$	17.0	$	(12.7)	$	(21.6)	$	(19.4)

Weighted-average assumptions used to determine benefit obligations and net periodic benefit cost for the plans

The weighted-average assumptions used to determine the benefit obligations for the plans were as follows for the years ended December 31:

	Pension Benefits		OPEB Benefits
	2023	2022	2023	2022
Discount rate	5.20%	5.50%	5.15%	5.50%
Rate of compensation increase	4.00%	4.00%	N/A	N/A
Interest credit rate	5.14%	5.14%	N/A	N/A
Assumed medical cost trend rate (Pre 65)	N/A	N/A	6.25%	6.50%
Ultimate trend rate (Pre 65)	N/A	N/A	5.00%	5.00%
Year ultimate trend rate is reached (Pre 65)	N/A	N/A	2031	2031
Assumed medical cost trend rate (Post 65)	N/A	N/A	6.55%	6.00%
Ultimate trend rate (Post 65)	N/A	N/A	5.00%	5.00%
Year ultimate trend rate is reached (Post 65)	N/A	N/A	2030	2031

The weighted-average assumptions used to determine the net periodic benefit cost for the plans were as follows for the years ended December 31:

	Pension Benefits
	2023	2022	2021
Discount rate	5.50%	2.94%	2.63%
Expected return on plan assets	6.50%	6.75%	6.75%
Rate of compensation increase	4.00%	4.00%	4.00%
Interest credit rate	5.14%	5.16%	5.16%

	OPEB Benefits
	2023	2022	2021
Discount rate	5.50%	2.95%	2.65%
Expected return on plan assets	6.50%	7.00%	7.00%
Assumed medical cost trend rate (Pre 65)	6.50%	5.70%	5.85%
Ultimate trend rate (Pre 65)	5.00%	5.00%	5.00%
Year ultimate trend rate is reached (Pre 65)	2031	2028	2028
Assumed medical cost trend rate (Post 65)	6.00%	5.72%	5.86%
Ultimate trend rate (Post 65)	5.00%	5.00%	5.00%
Year ultimate trend rate is reached (Post 65)	2031	2028	2028

Investments recorded at fair value, by asset class

The following tables provide the fair values of our investments by asset class:

	December 31, 2023
	Pension Plan Assets								OPEB Assets
(in millions)	Level 1		Level 2		Level 3		Total		Level 1		Level 2		Level 3		Total
Asset Class
Equity securities:
United States equity	$	57.4	$	—	$	—	$	57.4	$	17.3	$	—	$	—	$	17.3
International equity	51.4		—		—		51.4		16.3		—		—		16.3
Fixed income securities: (1)
United States bonds	—		404.1		—		404.1		13.4		52.4		—		65.8
International bonds	—		31.7		—		31.7		—		3.3		—		3.3
	$	108.8	$	435.8	$	—	$	544.6	$	47.0	$	55.7	$	—	$	102.7
Investments measured at net asset value:
Equity securities							137.9								34.4
Fixed income securities							0.1								6.3
Other							249.6								29.4
Total							$	932.2							$	172.8

(1)    This category represents investment grade bonds of United States and foreign issuers denominated in United States dollars from diverse industries.

	December 31, 2022
	Pension Plan Assets								OPEB Assets
(in millions)	Level 1		Level 2		Level 3		Total		Level 1		Level 2		Level 3		Total
Asset Class
Equity securities:
United States equity	$	69.5	$	—	$	—	$	69.5	$	23.6	$	—	$	—	$	23.6
International equity	60.8		—		—		60.8		20.2		—		—		20.2
Fixed income securities: (1)
United States bonds	—		419.2		—		419.2		25.8		45.8		—		71.6
International bonds	—		35.5		—		35.5		—		3.9		—		3.9
	$	130.3	$	454.7	$	—	$	585.0	$	69.6	$	49.7	$	—	$	119.3
Investments measured at net asset value:
Equity securities							139.7								47.3
Fixed income securities							—								12.7
Other							216.0								32.0
Total							$	940.7							$	211.3

(1)    This category represents investment grade bonds of United States and foreign issuers denominated in United States dollars from diverse industries.

Schedule of expected future benefit payments

The following table shows the payments, reflecting expected future service, that we expect to make for pension and OPEB over the next 10 years:

(in millions)	Pension Benefits		OPEB Benefits
2024	$	86.9	$	11.5
2025	80.3		11.3
2026	79.6		11.3
2027	76.0		11.5
2028	73.4		11.6
2029-2033	331.3		58.9

XML

Variable Interest Entities (Tables)

12 Months Ended

Dec. 31, 2023

Organization, Consolidation and Presentation of Financial Statements [Abstract]

Schedule of balance sheet impact of WEPCo Environmental Trust

The following table summarizes the impact of WEPCo Environmental Trust on our balance sheet:

(in millions)	December 31, 2023		December 31, 2022
Assets
Other current assets (restricted cash)	$	0.8	$	3.0
Regulatory assets	85.9		92.4
Other long-term assets (restricted cash)	0.6		0.6
Liabilities
Current portion of long-term debt	9.0		8.9
Other current liabilities (accrued interest)	0.1		0.1
Long-term debt	85.3		94.1

XML

Commitments and Contingencies (Tables)

12 Months Ended

Dec. 31, 2023

Commitments and Contingencies Disclosure [Abstract]

Schedule of minimum future commitments related to purchase obligations

The following table shows our minimum future commitments related to these purchase obligations as of December 31, 2023:

				Payments Due By Period
(in millions)	Date Contracts Extend Through	Total Amounts Committed		2024		2025		2026		2027		2028		Later Years
Electric utility:
Nuclear	2033	$	6,280.6	$	600.3	$	634.5	$	681.6	$	730.4	$	782.6	$	2,851.2
Coal supply and transportation	2026	354.9		247.9		94.2		12.8		—		—		—
Purchased power	2051	29.2		3.6		2.3		2.4		2.4		2.5		16.0
Natural gas utility supply and transportation	2048	460.8		68.2		39.9		33.2		28.6		25.1		265.8
Total		$	7,125.5	$	920.0	$	770.9	$	730.0	$	761.4	$	810.2	$	3,133.0

Schedule of regulatory assets and reserves related to manufactured gas plant sites

We have established the following regulatory assets and reserves for manufactured gas plant sites as of December 31:

(in millions)	2023		2022
Regulatory assets	$	12.2	$	14.6
Reserves for future environmental remediation (1)	$	10.3	$	10.3

(1)    Recorded within other long-term liabilities on our balance sheets.

XML

Supplemental Cash Flow Information (Tables)

12 Months Ended

Dec. 31, 2023

Additional Cash Flow Elements and Supplemental Cash Flow Information [Abstract]

Schedule of supplemental cash flow information

	Year Ended December 31
(in millions)	2023		2022		2021
Cash paid for interest, net of amount capitalized	$	463.8	$	449.2	$	460.8
Cash paid for income taxes, net (1)	99.1		88.0		88.0
Significant non-cash investing and financing transactions:
Accounts payable related to construction costs	71.8		89.1		42.4
Increase in receivables related to insurance proceeds	—		—		37.3
Liabilities accrued for software licensing agreement	—		3.1		—

(1)    Cash paid for income taxes in 2023 was net of $4.9 million of PTCs that were sold to a third party.

Reconciliation of cash, cash equivalents, and restricted cash

The following table reconciles the cash, cash equivalents, and restricted cash amounts reported within the balance sheets at December 31 to the total of these amounts shown on the statements of cash flows:

(in millions)	2023		2022		2021
Cash and cash equivalents	$	6.1	$	6.1	$	—
Restricted cash included in other current assets	0.8		3.0		2.4
Restricted cash included in other long-term assets	0.6		38.6		0.6
Cash, cash equivalents, and restricted cash	$	7.5	$	47.7	$	3.0

XML

Regulatory Environment (Tables)

12 Months Ended

Dec. 31, 2023

2024 Rate Case Re-Opener

Public Utilities, General Disclosures

Schedule of regulatory decisions

The final orders reflected the following:

2024 incremental rate increases
Electric (1)	$	82.2	million	/	2.5%
Gas	$	23.9	million	/	4.5%

(1)    Amount reflects the impact to our Wisconsin retail electric operations and includes the incremental increase from updated fuel costs.

2023 and 2024 Rates

Public Utilities, General Disclosures

Schedule of regulatory decisions

The final order reflected the following:

2023 base rate increase
Electric	$	283.5	million	/	9.1%
Gas	$	46.1	million	/	9.6%
Steam	$	7.6	million	/	35.3%
ROE	9.8%
Common equity component average on a financial basis	53.0%

2020 and 2021 rates

Public Utilities, General Disclosures

Schedule of regulatory decisions

The final order reflected the following:

2020 Effective rate increase
Electric (1)	$	15.3	million	/	0.5%
Gas (2)	$	10.4	million	/	2.8%
Steam	$	1.9	million	/	8.6%
ROE	10.0%
Common equity component average on a financial basis	52.5%

(1)    Amount is net of certain deferred tax benefits from the Tax Legislation that were utilized to reduce near-term rate impacts. The rate order reflected the majority of the unprotected deferred tax benefits from the Tax Legislation being amortized evenly over two years, which resulted in approximately $65 million of tax benefits being amortized in each of 2020 and 2021. The unprotected deferred tax benefits related to the unrecovered balances of certain of our retired plants and our SSR regulatory asset were used to reduce the related regulatory asset. Unprotected deferred tax benefits by their nature are eligible to be returned to customers in a manner and timeline determined to be appropriate by the PSCW.

(2)    Amount includes certain deferred tax expense from the Tax Legislation. The rate order reflected all of the unprotected deferred tax expense from the Tax Legislation being amortized evenly over four years, which resulted in approximately $5 million of previously deferred tax expense being amortized each year. Unprotected deferred tax expense by its nature is eligible to be recovered from customers in a manner and timeline determined to be appropriate by the PSCW.

XML

Other Income, Net (Tables)

12 Months Ended

Dec. 31, 2023

Other Income and Expenses [Abstract]

Schedule of other income, net

Total other income, net was as follows for the years ended December 31:

(in millions)	2023		2022		2021
AFUDC-Equity	$	41.0	$	18.8	$	7.9
Non-service components of net periodic benefit costs	24.1		33.8		22.5
Other, net	3.7		(3.2)		1.7
Other income, net	$	68.8	$	49.4	$	32.1

XML

Summary of Significant Accounting Policies Cash and Cash Equivalents (Details)	12 Months Ended
	Dec. 31, 2023
Accounting Policies [Abstract]
Maximum term of original maturity to classify instrument as cash equivalent	3 months

XML

Summary of Significant Accounting Policies Operating Revenues (Details)	12 Months Ended
	Dec. 31, 2023 performance_obligations contract
Electric
Disaggregation of Operating Revenues
Number of days payment is due	30 days
Electric | Retail
Disaggregation of Operating Revenues
Number of performance obligations	1
Percent fuel and purchased power costs can vary from the rate case approved costs before deferral is required	2.00%
Electric | Wholesale
Disaggregation of Operating Revenues
Number of performance obligations	2
Number of contracts | contract	1
Natural gas
Disaggregation of Operating Revenues
Number of days payment is due	30 days

XML

Summary of Significant Accounting Policies Credit Losses (Details) - USD ($) $ in Millions	Dec. 31, 2023	Dec. 31, 2022
Other
Accounts, Notes, Loans and Financing Receivable [Line Items]
Accounts receivable and unbilled revenues	$ 0.0	$ 0.0

XML

Summary of Significant Accounting Policies Materials, Supplies, and Inventories (Details) - USD ($) $ in Millions	Dec. 31, 2023	Dec. 31, 2022
Accounting Policies [Abstract]
Materials and supplies	$ 186.6	$ 150.6
Fossil fuel	74.5	62.7
Natural gas in storage	49.5	79.6
Total	$ 310.6	$ 292.9

XML

Summary of Significant Accounting Policies Property, Plant, and Equipment (Details)	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Property, plant, and equipment
Annual utility composite depreciation rate (as a percent)	3.03%	3.06%	3.09%
Software | Minimum
Property, plant, and equipment
Estimated useful life	3 years
Software | Maximum
Property, plant, and equipment
Estimated useful life	15 years

XML

Summary of Significant Accounting Policies Allowance for Funds Used During Construction (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Allowance for funds used during construction
AFUDC - Debt	$ 13.0	$ 6.9	$ 2.9
AFUDC - Equity	$ 41.0	$ 18.8	$ 7.9
Retail operations
Allowance for funds used during construction
Percentage of retail jurisdictional construction work in progress expenditure subject to AFUDC	50.00%
Average AFUDC rate (as a percent)	8.45%	8.68%	8.68%
Wholesale operations
Allowance for funds used during construction
Average AFUDC rate (as a percent)	6.70%	5.35%	1.79%

XML

Summary of Significant Accounting Policies Asset Impairment (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Accounting Policies [Abstract]
Indefinite-lived intangible assets	$ 12.1	$ 9.1
Impairment losses for indefinite-lived intangible assets	$ 0.0	$ 0.0

XML

Summary of Significant Accounting Policies Stock-Based Compensation (Details) - $ / shares	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021	May 06, 2021
Share-based Compensation Arrangement by Share-based Payment Award
Number of shares of WEC Energy Group common stock authorized for issuance				9,000,000
Stock options
Share-based Compensation Arrangement by Share-based Payment Award
Vesting period (in years)	3 years
Minimum exercise price of stock option as a percent of WEC Energy Group common stock fair value on the grant date	100.00%
Period after the grant date during which stock options can't be exercised (in months)	6 months
Maximum term of awards (in years)	10 years
Stock options granted (in shares)	30,495	51,511	60,108
Estimated weighted-average fair value per stock option (in dollars per share)	$ 19.58	$ 14.71	$ 13.20
Risk-free interest rate, minimum (as a percent)	3.80%	0.20%	0.10%
Risk-free interest rate, maximum (as a percent)	4.80%	1.60%	0.90%
Dividend yield (as a percent)	3.20%	3.20%	2.90%
Expected volatility (as a percent)	22.00%	21.00%	21.00%
Expected life (years)	8 years 3 months 18 days	8 years 8 months 12 days	8 years 8 months 12 days
Restricted stock
Share-based Compensation Arrangement by Share-based Payment Award
Vesting period (in years)	3 years
Percentage to vest each year after the grant date	33.00%
Performance units
Share-based Compensation Arrangement by Share-based Payment Award
Vesting period (in years)	3 years
Performance units | Performance units granted prior to 2023
Share-based Compensation Arrangement by Share-based Payment Award
Maximum adjustment to payout ratio	10.00%
Performance units | Performance units granted prior to 2023 | Minimum
Share-based Compensation Arrangement by Share-based Payment Award
Payout ratio (as a percent)	0.00%
Performance units | Performance units granted prior to 2023 | Maximum
Share-based Compensation Arrangement by Share-based Payment Award
Payout ratio (as a percent)	175.00%
Performance units | Performance units granted after January 1, 2023
Share-based Compensation Arrangement by Share-based Payment Award
Vesting period (in years)	3 years
Maximum adjustment to payout ratio	25.00%
Percentage of payout based on total shareholder return	55.00%
Percentage of payout based on ROE	45.00%
Performance units | Performance units granted after January 1, 2023 | Maximum
Share-based Compensation Arrangement by Share-based Payment Award
Payout ratio (as a percent)	200.00%

XML

Summary of Significant Accounting Policies -Leases (Details)	Dec. 31, 2023
Accounting Policies [Abstract]
Minimum lease term to recognize right of use asset and lease liabilities	1 year

XML

Summary of Significant Accounting Policies Guarantees (Details) $ in Millions	Dec. 31, 2023 USD ($)
Standby letters of credit
Guarantor Obligations [Line Items]
Guarantee	$ 26.0

XML

Summary of Significant Accounting Policies Customer Concentrations of Credit Risk (Details) - Customer concentration risk	12 Months Ended
	Dec. 31, 2023 customer
Customer concentration risk
Number of customers that account for more than 10% of revenues	0
Revenue Benchmark | Fair Value, Concentration of Risk, All Financial Instruments
Customer concentration risk
Threshold percentage of revenues from major customers	10.00%

XML

Acquisitions - West Riverside (Details) - West Riverside $ in Millions	1 Months Ended
	Sep. 30, 2023 USD ($) MW	Jun. 30, 2023 USD ($) MW
Asset Acquisition [Line Items]
Capacity of generation unit (in megawatts) | MW	100	100
Total purchase price		$ 95.3
Asset acquisition price, estimated	$ 100.0

XML

Acquisitions - Whitewater (Details) - Whitewater $ in Millions	1 Months Ended
	Jan. 31, 2023 USD ($)	Jan. 01, 2023 MW
Asset Acquisition [Line Items]
Capacity of generation unit (in megawatts) | MW		236.5
Asset acquisition price, estimated | $	$ 38.0
Ownership (as a percentage)		50.00%

XML

Disposition (Details) $ in Millions	1 Months Ended
	Jun. 30, 2023 USD ($) a
Discontinued Operations and Disposal Groups [Abstract]
NumberofAcresSold | a	192
Proceeds from sale of real estate	$ 23.0
Pre-tax gain on sale of real estate	$ 22.2

XML

Related Parties - Receivables and Payables with ATC (Details) - ATC - USD ($) $ in Millions	Dec. 31, 2023	Dec. 31, 2022
Related parties
Services provided to ATC	$ 0.9	$ 0.7
Amounts due from ATC for transmission infrastructure upgrades	39.5	23.3
Services received from ATC	$ 36.7	$ 20.0

XML

Related Parties - Other Transactions (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Related parties
Charges from related party for services and other items	$ 931.1	$ 831.7	$ 898.4
Natural gas related sales	4,045.0	4,070.3	3,664.5
WPS
Related parties
Charges to related party for services and other items	16.2	13.3	11.8
Charges from related party for services and other items	11.3	10.7	9.4
WPS | Natural gas
Related parties
Natural gas related purchases	1.3	3.3	2.9
WG
Related parties
Charges to related party for services and other items	38.3	39.5	40.4
Charges from related party for services and other items	27.9	29.8	29.7
WG | Natural gas
Related parties
Natural gas related purchases	19.7	6.2	5.9
Natural gas related sales	0.3	1.3	0.3
UMERC
Related parties
Charges to related party for services and other items	11.8	13.7	10.5
Charges from related party for services and other items	2.0	1.2	1.2
Bluewater
Related parties
Charges to related party for services and other items	2.7	2.7	3.0
Bluewater | Natural gas
Related parties
Natural gas related sales	2.8	2.7	2.6
Bluewater | Natural gas storage
Related parties
Natural gas related purchases	17.2	14.8	13.6
Other operating fees	4.1	3.3	1.4
We Power LLC
Related parties
Charges to related party for services and other items	7.8	4.2	6.7
Lease payments and other lease-related charges	422.0	412.6	406.0
WBS
Related parties
Charges to related party for services and other items	41.1	49.5	67.8
Charges from related party for services and other items	113.3	123.1	123.8
Proceeds from the transfer of certain sofware assets to WBS			11.3
ATC
Related parties
Charges to related party for services and other items	8.1	9.3	14.9
Charges from related party for services and other items	248.8	239.3	240.4
Net refund (payment) from (to) ATC related to FERC ROE orders	$ 0.0	$ (0.1)	$ 5.1

XML

Operating Revenues - Disaggregation of Operating Revenues (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Disaggregation of Operating Revenues
Operating revenues	$ 4,045.0	$ 4,070.3	$ 3,664.5
Utility
Disaggregation of Operating Revenues
Operating revenues	4,045.0	4,070.3	3,664.5
Utility | Other operating revenues
Disaggregation of Operating Revenues
Other operating revenues	15.0	14.8	18.7
Utility | Transferred over time | Revenues from contracts with customers
Disaggregation of Operating Revenues
Revenues from contracts with customers	4,030.0	4,055.5	3,645.8
Utility | Electric | Transferred over time | Revenues from contracts with customers
Disaggregation of Operating Revenues
Revenues from contracts with customers	3,540.2	3,448.7	3,171.6
Utility | Natural gas | Transferred over time | Revenues from contracts with customers
Disaggregation of Operating Revenues
Revenues from contracts with customers	$ 489.8	$ 606.8	$ 474.2

XML

Operating Revenues Electric Utility Operating Revenues (Details) - Utility - Revenues from contracts with customers - Transferred over time - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Disaggregation of Operating Revenues
Revenues from contracts with customers	$ 4,030.0	$ 4,055.5	$ 3,645.8
Electric
Disaggregation of Operating Revenues
Revenues from contracts with customers	3,540.2	3,448.7	3,171.6
Electric | Total retail
Disaggregation of Operating Revenues
Revenues from contracts with customers	3,294.9	3,120.8	2,914.7
Electric | Residential
Disaggregation of Operating Revenues
Revenues from contracts with customers	1,480.6	1,376.3	1,306.2
Electric | Small commercial and industrial
Disaggregation of Operating Revenues
Revenues from contracts with customers	1,177.2	1,095.0	1,019.7
Electric | Large commercial and industrial
Disaggregation of Operating Revenues
Revenues from contracts with customers	616.0	629.1	568.6
Electric | Other
Disaggregation of Operating Revenues
Revenues from contracts with customers	21.1	20.4	20.2
Electric | Wholesale
Disaggregation of Operating Revenues
Revenues from contracts with customers	40.9	58.4	71.0
Electric | Resale
Disaggregation of Operating Revenues
Revenues from contracts with customers	173.7	224.3	148.2
Electric | Steam
Disaggregation of Operating Revenues
Revenues from contracts with customers	25.2	28.4	28.7
Electric | Other utility
Disaggregation of Operating Revenues
Revenues from contracts with customers	$ 5.5	$ 16.8	$ 9.0

XML

Operating Revenues Natural Gas Utility Operating Revenues (Details) - Revenues from contracts with customers - Utility - Transferred over time - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Disaggregation of Operating Revenues
Revenues from contracts with customers	$ 4,030.0	$ 4,055.5	$ 3,645.8
Natural gas
Disaggregation of Operating Revenues
Revenues from contracts with customers	489.8	606.8	474.2
Natural gas | Total retail
Disaggregation of Operating Revenues
Revenues from contracts with customers	471.5	591.5	451.0
Natural gas | Residential
Disaggregation of Operating Revenues
Revenues from contracts with customers	323.3	397.8	309.1
Natural gas | Commercial and industrial
Disaggregation of Operating Revenues
Revenues from contracts with customers	148.2	193.7	141.9
Natural gas | Transport
Disaggregation of Operating Revenues
Revenues from contracts with customers	21.6	17.8	17.3
Natural gas | Other utility
Disaggregation of Operating Revenues
Revenues from contracts with customers	$ (3.3)	$ (2.5)	$ 5.9

XML

Operating Revenues - Other Operating Revenues (Details) - Utility - Other operating revenues - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Disaggregation of Operating Revenues
Other operating revenues	$ 15.0	$ 14.8	$ 18.7
Late payment charges
Disaggregation of Operating Revenues
Other operating revenues	12.2	12.1	13.3
Rental revenues
Disaggregation of Operating Revenues
Other operating revenues	2.5	2.5	3.0
Alternative revenues
Disaggregation of Operating Revenues
Other operating revenues	$ 0.3	$ 0.2	$ 2.4

XML

Credit Losses - Gross Receivables and Related Allowances (Details) - Utility - USD ($) $ in Millions	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Accounts, Notes, Loans and Financing Receivable [Line Items]
Accounts receivable and unbilled revenues	$ 617.5	$ 632.3
Allowance for credit losses	44.5	49.7	$ 51.4	$ 59.3
Accounts receivable and unbilled revenues, net	573.0	582.6
Total accounts receivable, net - past due greater than 90 days	$ 37.2	$ 35.8
Past due greater than 90 days - collection risk mitigated by regulatory mechanisms	94.10%	97.50%
Amount of net accounts receivable with regulatory protections	$ 342.5
Percent of net accounts receivable with regulatory protections	59.80%

XML

Credit Losses - Rollforward of Allowances (Details) - Utility - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Accounts Receivable, Allowance for Credit Loss [Roll Forward]
Balance at January 1	$ 49.7	$ 51.4	$ 59.3
Provision for credit losses	23.8	27.3	24.8
Write-offs charged against the allowance	(94.1)	(83.4)	(47.6)
Recoveries of amounts previously written off	19.4	20.4	15.2
Balance at December 31	44.5	49.7	51.4
Uncollectible expense
Accounts Receivable, Allowance for Credit Loss [Roll Forward]
Provision for credit losses deferred for future recovery or refund	$ 45.7	$ 34.0	$ (0.3)

XML

Regulatory Assets and Liabilities - Regulatory Assets (Details) - USD ($) $ in Millions	Dec. 31, 2023	Dec. 31, 2022	Jan. 01, 2020
Regulatory assets
Total regulatory assets	$ 2,860.7	$ 2,817.5
Allowance for return on equity capitalized for regulatory purposes	16.5	14.7
Regulatory assets not earning a return	1.9
Regulatory assets earning a return based on short-term interest rates	4.7
Regulatory assets earning a return based on long-term interest rates	129.7
Finance leases
Regulatory assets
Total regulatory assets	1,109.7	1,072.0
Plant retirement related items
Regulatory assets
Total regulatory assets	595.5	632.7
Income tax related items
Regulatory assets
Total regulatory assets	373.1	382.1
Pension and OPEB costs
Regulatory assets
Total regulatory assets	348.9	337.2
System support resource (SSR)
Regulatory assets
Total regulatory assets	113.2	123.5
Recovery period of regulatory asset			15 years
Securitization
Regulatory assets
Total regulatory assets	85.9	92.4
Uncollectible expense
Regulatory assets
Total regulatory assets	62.1	16.4
Derivatives
Regulatory assets
Total regulatory assets	45.2	40.3
Asset retirement obligations (AROs)
Regulatory assets
Total regulatory assets	41.2	41.1
Energy efficiency programs
Regulatory assets
Total regulatory assets	23.3	17.7
We Power generation
Regulatory assets
Total regulatory assets	4.7	21.6
Other, net
Regulatory assets
Total regulatory assets	$ 57.9	$ 40.5

XML

Regulatory Assets and Liabilities - Regulatory Liabilities (Details) - USD ($) $ in Millions	Dec. 31, 2023	Dec. 31, 2022
Regulatory liabilities
Other current liabilities	$ 5.3	$ 1.4
Regulatory liabilities	1,631.4	1,637.4
Total regulatory liabilities	1,636.7	1,638.8
Removal costs
Regulatory liabilities
Total regulatory liabilities	758.9	718.1
Income tax related items
Regulatory liabilities
Total regulatory liabilities	683.5	716.1
Pension and OPEB benefits
Regulatory liabilities
Total regulatory liabilities	124.0	144.4
Electric transmission costs
Regulatory liabilities
Total regulatory liabilities	23.9	0.2
Energy efficiency programs
Regulatory liabilities
Total regulatory liabilities	10.6	1.0
Derivatives
Regulatory liabilities
Total regulatory liabilities	4.5	39.1
Other, net
Regulatory liabilities
Total regulatory liabilities	$ 31.3	$ 19.9

XML

Regulatory Assets and Liabilities - Plant Retirements (Details) - USD ($) $ in Millions	Dec. 31, 2023	Dec. 31, 2022	May 31, 2021
Regulatory assets
Total regulatory assets	$ 2,860.7	$ 2,817.5
Deferred tax liabilities	1,430.4	1,399.0
Securitization
Regulatory assets
Total regulatory assets	85.9	$ 92.4
Pleasant Prairie power plant
Regulatory assets
Net book value of retired plant	542.4
Deferred unprotected tax benefits	16.4
Total regulatory assets	526.0
Deferred tax liabilities	147.8
Pleasant Prairie power plant | Securitization
Regulatory assets
Total regulatory assets			$ 100.0
Presque Isle power plant
Regulatory assets
Net book value of retired plant	141.2
Deferred unprotected tax benefits	4.8
Total regulatory assets	136.4
Deferred tax liabilities	$ 38.5

XML

Property, Plant, and Equipment - Balances (Details) $ in Millions	Dec. 31, 2023 USD ($)	Sep. 30, 2023 MW	Jun. 30, 2023 MW	Dec. 31, 2022 USD ($)
Property, Plant and Equipment [Line Items]
Accumulated depreciation	$ 5,779.2			$ 5,450.3
Property, plant, and equipment	11,585.5			10,718.6
West Riverside
Property, Plant and Equipment [Line Items]
Capacity of generation unit (in megawatts) | MW		100	100
OCPP generating units 5-8
Property, Plant and Equipment [Line Items]
Net book value of plant to be retired	783.7
Regulated operations
Property, Plant and Equipment [Line Items]
Accumulated depreciation	3,530.3			3,213.4
Net	9,237.8			8,423.4
CWIP	624.7			556.1
Property, plant, and equipment	9,862.5			8,979.5
Regulated operations | Electric - generation
Property, Plant and Equipment [Line Items]
Property, Plant And Equipment, Gross, Excluding Construction Work In Progress and Finance/Capital Leases	2,721.3			2,200.0
Regulated operations | Electric - distribution
Property, Plant and Equipment [Line Items]
Property, Plant And Equipment, Gross, Excluding Construction Work In Progress and Finance/Capital Leases	6,116.7			5,822.4
Regulated operations | Natural gas - distribution, storage, and transmission
Property, Plant and Equipment [Line Items]
Property, Plant And Equipment, Gross, Excluding Construction Work In Progress and Finance/Capital Leases	2,059.4			1,757.0
Regulated operations | Other
Property, Plant and Equipment [Line Items]
Property, Plant And Equipment, Gross, Excluding Construction Work In Progress and Finance/Capital Leases	1,087.0			1,044.9
Regulated operations | Finance leases
Property, Plant and Equipment [Line Items]
Property under finance leases	3,206.8			3,248.8
Accumulated amortization	1,483.8			1,509.7
Net leased facilities	1,723.0			1,739.1
Regulated operations | OCPP generating units 5-8
Property, Plant and Equipment [Line Items]
Net book value of plant to be retired	$ 783.7			$ 812.5

XML

Property, Plant, and Equipment - Severance Liability (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Property, Plant and Equipment [Abstract]
Severance liability at January 1	$ 13.5	$ 3.3	$ 0.7
Severance expense	1.6	10.2	3.0
Severance payments	0.0	0.0	(0.4)
Severance liability at December 31	$ 15.1	$ 13.5	$ 3.3

XML

Property, Plant, and Equipment - Public Service Building (Details) $ in Millions	Dec. 31, 2023 USD ($)
Building
Property, plant, and equipment
Costs incurred for repairs and restorations	$ 95.3

XML

Jointly Owned Utility Facilities (Details) $ in Millions	Dec. 31, 2023 USD ($) MW	Sep. 30, 2023 MW
West Riverside
Jointly owned utility facilities
Share of capacity (MW) | MW		100
West Riverside
Jointly owned utility facilities
Ownership (as a percentage)	13.80%
Share of capacity (MW) | MW	84.9
Property, plant, and equipment	$ 108.7
Accumulated depreciation	(11.3)
Construction work in progress	$ 0.9
Badger Hollow II
Jointly owned utility facilities
Ownership (as a percentage)	66.70%
Share of capacity (MW) | MW	100.0
Property, plant, and equipment	$ 170.1
Accumulated depreciation	(0.3)
Construction work in progress	$ 0.1
Weston RICE units
Jointly owned utility facilities
Ownership (as a percentage)	50.00%
Share of capacity (MW) | MW	65.0
Property, plant, and equipment	$ 92.4
Accumulated depreciation	(1.3)
Construction work in progress	$ 0.0
Whitewater
Jointly owned utility facilities
Ownership (as a percentage)	50.00%
Share of capacity (MW) | MW	121.4
Property, plant, and equipment	$ 125.7
Accumulated depreciation	(93.6)
Construction work in progress	$ 0.3
Koshkonong
Jointly owned utility facilities
Ownership (as a percentage)	75.00%
Jointly owned utility plant, proportionate ownership share of solar capacity | MW	225
Paris
Jointly owned utility facilities
Ownership (as a percentage)	75.00%
Construction work in progress	$ 279.1
Jointly owned utility plant, proportionate ownership share of solar capacity | MW	150
Jointly owned utility plant, proportionate ownership share of battery storage | MW	82
Darien
Jointly owned utility facilities
Ownership (as a percentage)	75.00%
Construction work in progress	$ 183.8
Jointly owned utility plant, proportionate ownership share of solar capacity | MW	188

XML

Asset Retirement Obligations (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Changes to asset retirement obligations
Balance as of January 1	$ 71.7	$ 70.8	$ 54.5
Accretion	1.8	1.8	1.7
Additions	4.4	0.0	0.0
Revisions to estimated cash flows	(4.5)	0.3	17.3
Liabilities settled	(0.3)	(1.2)	(2.7)
Balance as of December 31	$ 73.1	$ 71.7	$ 70.8

XML

Common Equity - Stock-Based Compensation Expense (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Share Based Compensation Arrangement By Share Based Payment Award
Stock-based compensation expense	$ 3.3	$ 13.2	$ 6.2
Related tax benefit	0.9	3.6	1.7
Stock options
Share Based Compensation Arrangement By Share Based Payment Award
Stock-based compensation expense	1.9	2.4	2.3
Restricted stock
Share Based Compensation Arrangement By Share Based Payment Award
Stock-based compensation expense	2.3	2.3	2.2
Performance units
Share Based Compensation Arrangement By Share Based Payment Award
Stock-based compensation expense	$ (0.9)	$ 8.5	$ 1.7

XML

Common Equity - Stock Options (Details) - Stock options - USD ($) $ / shares in Units, $ in Millions	3 Months Ended	12 Months Ended
	Mar. 31, 2024	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Options Activity
Outstanding, shares, beginning balance	448,300	475,509
Granted, shares		30,495	51,511	60,108
Exercised, shares		(57,704)
Outstanding, shares, ending balance		448,300	475,509
Options - Weighted Average Exercise Price
Outstanding, Weighted-Average Exercise Price, Beginning	$ 75.67	$ 70.63
Granted, Weighted-Average Exercise Price		93.69
Exercised, Weighted-Average Exercise Price		43.70
Outstanding, Weighted-Average Exercise Price, Ending		$ 75.67	$ 70.63
Options - Additional Disclosures
Outstanding, Weighted-Average Remaining Contractual Life (Years)		5 years 1 month 6 days
Outstanding, Aggregate Intrinsic Value		$ 5.6
Exercisable, shares		332,592
Exercisable, Weighted-Average Exercise Price		$ 69.45
Exercisable, Weighted-Average Remaining Contractual Life (Years)		4 years 2 months 12 days
Exercisable, Aggregate Intrinsic Value		$ 5.6
Intrinsic value of options exercised		2.5	$ 6.1	$ 2.9
Tax benefit from option exercises		0.7	$ 1.7	$ 0.8
Compensation cost not yet recognized		$ 0.5
Weighted-average period over which unrecognized compensation cost is expected to be recognized		1 year 7 months 6 days
Estimated weighted-average fair value per stock option (in dollars per share)		$ 19.58	$ 14.71	$ 13.20
Subsequent event
Options Activity
Granted, shares	33,081
Options - Weighted Average Exercise Price
Granted, Weighted-Average Exercise Price	$ 85.05
Options - Additional Disclosures
Estimated weighted-average fair value per stock option (in dollars per share)	$ 16.20
WEC Energy Group
Options - Additional Disclosures
Cash received by WEC Energy Group from options exercised by WE employees		$ 2.5	$ 4.3	$ 2.6

XML

Common Equity - Restricted Shares (Details) - Restricted stock - USD ($) $ / shares in Units, $ in Millions	3 Months Ended	12 Months Ended
	Mar. 31, 2024	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Restricted Stock Activity
Outstanding, shares, beginning of period	8,171	7,208
Granted, shares		4,544
Released, shares		(3,358)
Forfeited, shares		(223)
Outstanding, shares, end of period		8,171	7,208
Restricted Stock Weighted-Average Grant Date Fair Value
Outstanding, weighted-average grant date fair value, beginning of period	$ 94.12	$ 93.97
Granted, weighted-average grant date fair value		93.69
Released, weighted-average grant date fair value		93.21
Forfeited, weighted-average grant date fair value		94.13
Outstanding, weighted-average grant date fair value, end of period		$ 94.12	$ 93.97
Restricted Stock - Additional Disclosures
Intrinsic value of released restricted shares		$ 0.3	$ 0.4	$ 0.4
Tax benefit from released restricted shares		0.1	$ 0.1	$ 0.1
Compensation cost not yet recognized		$ 1.1
Weighted-average period over which unrecognized compensation cost is expected to be recognized		1 year 8 months 12 days
Subsequent event
Restricted Stock Activity
Granted, shares	7,754
Restricted Stock Weighted-Average Grant Date Fair Value
Granted, weighted-average grant date fair value	$ 85.05

XML

Common Equity - Performance Units (Details) - Performance units - USD ($) $ in Millions	3 Months Ended	12 Months Ended
	Mar. 31, 2024	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Share-based Compensation Arrangement by Share-based Payment Award
Performance units granted		19,780	21,158	18,138
Intrinsic value of settled performance units		$ 1.2	$ 2.8	$ 3.1
Tax benefit from distribution of performance units		$ 0.3	$ 0.7	$ 0.7
Performance units outstanding		53,116
Liability recorded on balance sheet		$ 1.3
Compensation cost not yet recognized		$ 5.2
Weighted-average period over which unrecognized compensation cost is expected to be recognized		1 year 10 months 24 days
Subsequent event
Share-based Compensation Arrangement by Share-based Payment Award
Performance units granted	25,242
Intrinsic value of settled performance units	$ 0.1

XML

Common Equity - Dividend Restrictions (Details)	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Serial preferred stock, 3.60% Series
Dividend Payment Restrictions
Preferred Stock, dividend rate (as a percent)	3.60%	3.60%
Serial preferred stock, 3.60% Series | Common stock equity to total capitalization is between 25% and 20%
Dividend Payment Restrictions
Period of dividend restrictions	12 months
Serial preferred stock, 3.60% Series | Common stock equity to total capitalization is less than 20%
Dividend Payment Restrictions
Period of dividend restrictions	12 months
Minimum | Serial preferred stock, 3.60% Series | Common stock equity to total capitalization is between 25% and 20%
Dividend Payment Restrictions
Percentage of common equity to total capitalization required to be maintained	20.00%
Maximum | Serial preferred stock, 3.60% Series | Common stock equity to total capitalization is between 25% and 20%
Dividend Payment Restrictions
Percentage of net income for which dividends can be declared	75.00%
Percentage of common equity to total capitalization required to be maintained	25.00%
Maximum | Serial preferred stock, 3.60% Series | Common stock equity to total capitalization is less than 20%
Dividend Payment Restrictions
Percentage of net income for which dividends can be declared	50.00%
Percentage of common equity to total capitalization required to be maintained	20.00%
Public Service Commission of Wisconsin | Minimum
Dividend Payment Restrictions
Common equity ratio required to be maintained (as a percent)	53.00%

XML

Preferred Stock (Details) - USD ($) $ / shares in Units, $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Class of Stock
Total preferred stock value issued	$ 30.4	$ 30.4
$100 par value, Six Per Cent. Preferred Stock
Class of Stock
Par or stated value per share	$ 100	$ 100
Dividend rate (as a percentage)	6.00%	6.00%
Shares authorized	45,000	45,000
Shares outstanding	44,498	44,498
Redemption price per share	$ 0	$ 0
Total preferred stock value issued	$ 4.4	$ 4.4
$100 par value, Serial Preferred Stock, 3.60% Series
Class of Stock
Par or stated value per share	$ 100	$ 100
Dividend rate (as a percentage)	3.60%	3.60%
Shares authorized	2,286,500	2,286,500
Shares outstanding	260,000	260,000
Redemption price per share	$ 101	$ 101
Total preferred stock value issued	$ 26.0	$ 26.0
$25 par value, Serial Preferred Stock
Class of Stock
Par or stated value per share	$ 25	$ 25
Shares authorized	5,000,000	5,000,000
Shares outstanding	0	0
Redemption price per share	$ 0	$ 0
Total preferred stock value issued	$ 0.0	$ 0.0

XML

Short-Term Debt and Lines of Credit Outstanding (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Short-term Debt [Line Items]
Maximum debt to capitalization ratio required to be maintained (as a percent)	65.00%
Commercial Paper
Short-term Debt [Line Items]
Commercial paper outstanding	$ 360.8	$ 460.7
Average interest rate on amounts outstanding	5.48%	4.59%
Average amounts outstanding during year	$ 109.9
Weighted average interest rate during the year	5.19%

XML

Short-Term Debt and Lines of Credit - Credit Facilities (Details) $ in Millions	12 Months Ended
	Dec. 31, 2023 USD ($) extension	Dec. 31, 2022 USD ($)
Line of Credit Facility [Line Items]
Available capacity under existing agreements	$ 138.2
Number of extensions available on a credit facility | extension	2
Length of credit facility extension	1 year
Credit facility maturing September 2026
Line of Credit Facility [Line Items]
Short-term credit capacity	$ 500.0
Letters of Credit
Line of Credit Facility [Line Items]
Letters of credit issued inside credit facilities	1.0
Commercial Paper
Line of Credit Facility [Line Items]
Commercial paper outstanding	$ 360.8	$ 460.7

XML

Long-Term Debt (Details) - USD ($) $ in Millions	Dec. 31, 2023	Dec. 31, 2022
Long-term debt
Total	$ 3,382.0	$ 3,390.9
Unamortized debt issuance costs	(13.0)	(14.9)
Unamortized discount, net	(14.6)	(15.6)
Long-term debt including current portion	3,354.4	3,360.4
Current portion of long-term debt	(309.0)	(8.9)
Long-term debt	3,045.4	3,351.5
Future maturities of long-term debt outstanding
2024	309.0
2025	259.2
2026	9.3
2027	9.5
2028	459.6
Thereafter	2,335.4
Total	$ 3,382.0	3,390.9
Debentures (unsecured), 2.05% due 2024
Long-term debt
Interest rate	2.05%
Unsecured debt	$ 300.0	300.0
Debentures (unsecured), 3.10% due 2025
Long-term debt
Interest rate	3.10%
Unsecured debt	$ 250.0	250.0
Debentures (unsecured), 6.50% due 2028
Long-term debt
Interest rate	6.50%
Unsecured debt	$ 150.0	150.0
Debentures (unsecured), 1.70% due 2028
Long-term debt
Interest rate	1.70%
Unsecured debt	$ 300.0	300.0
WE 4.75% Debentures due September 30, 2032
Long-term debt
Interest rate	4.75%
Unsecured debt	$ 500.0	500.0
Debentures (unsecured), 5.625% due 2033
Long-term debt
Interest rate	5.625%
Unsecured debt	$ 335.0	335.0
Debentures (unsecured), 5.70% due 2036
Long-term debt
Interest rate	5.70%
Unsecured debt	$ 300.0	300.0
Debentures (unsecured), 3.65% due 2042
Long-term debt
Interest rate	3.65%
Unsecured debt	$ 250.0	250.0
Debentures (unsecured), 4.25% due 2044
Long-term debt
Interest rate	4.25%
Unsecured debt	$ 250.0	250.0
Debentures (unsecured), 4.30% due 2045
Long-term debt
Interest rate	4.30%
Unsecured debt	$ 250.0	250.0
Debentures (unsecured), 4.30% due 2048
Long-term debt
Interest rate	4.30%
Unsecured debt	$ 300.0	300.0
Debentures (unsecured), 6.875% due 2095
Long-term debt
Interest rate	6.875%
Unsecured debt	$ 100.0	100.0
Trust Bonds (secured), 1.578%, due 2035
Long-term debt
Interest rate	1.578%
Secured Debt	$ 97.0	$ 105.9

XML

Leases - Power Purchase Commitment (Details) - MW	5 Months Ended
	May 31, 2022	Jan. 01, 2023
Whitewater
Leases
Ownership (as a percentage)		50.00%
Power purchase commitment
Leases
Power purchase contract period	25 years
Firm capacity from power purchase contract (in megawatts)	236.5
Minimum energy requirements over remaining term of power purchase contract (in megawatts)	0

XML

Leases - Port Washington Generating Station (Details) - Port Washington Generating Station	Dec. 31, 2023 generating_units contract renewal_terms MW
Leases
Number of generation units at the Port Washington Generating Station	2
Capacity of generation unit (in megawatts) | MW	545
Lease term	25 years
Minimum number of contracts that can be renewed | contract	1
Maximum number of consecutive renewal terms | renewal_terms	3
Increase to contract term if renewal selected (as percent of remaining economic life of generation unit)	80.00%
Minimum number of generation units that can be purchased	1

XML

Leases - Elm Road Generating Station (Details) - Elm Road Generating Station	Dec. 31, 2023 contract renewal_terms generating_units
Leases
Lease term	30 years
Minimum number of contracts that can be renewed | contract	1
Maximum number of consecutive renewal terms | renewal_terms	3
Increase to contract term if renewal selected (as percent of remaining economic life of generation unit)	80.00%
Minimum number of generation units that can be purchased | generating_units	1

XML

Leases - Land Leases - Utility Solar Generation (Details) - Land Lease - Utility Solar Generation	12 Months Ended
	Dec. 31, 2023 renewal_terms
Leases
Minimum number of contract renewals	1
Lease term	50 years

XML

Leases - Lease Expense and Supplemental Cash Flow Information (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Lease expense
Amortization of finance lease right of use assets	$ 77.5	$ 74.2	$ 68.1
Interest on finance lease liabilities	329.5	334.3	341.2
Operating lease expense	1.6	1.8	1.4
Total lease expense	408.6	410.3	410.7
Other information
Operating cash flows from finance leases	329.5	334.3	341.2
Operating cash flows from operating leases	1.6	1.8	1.4
Financing cash flows from finance leases	77.0	73.6	67.5
Noncash activity - right of use assets obtained in exchange for finance lease liability	136.5	60.0	52.7
Noncash activity - right of use assets obtained in exchange for operating lease liabilities	$ 2.3	$ 0.0	$ 0.3
Weighted average remaining lease term - finance leases	16 years 2 months 12 days	16 years 6 months	16 years 10 months 24 days
Weighted average remaining lease term - operating leases	24 years 10 months 24 days	27 years	28 years 6 months
Weighted average discount rate - finance leases	13.40%	13.60%	13.80%
Weighted average discount rate - operating leases	4.80%	4.50%	4.50%

XML

Leases - Finance and Operating Lease Right of Use Assets and Obligations (Details) - USD ($) $ in Millions	Dec. 31, 2023	Dec. 31, 2022
Right of use assets [Abstract]
Operating lease right of use assets	$ 10.2	$ 8.4
Finance lease right of use assets, net	1,723.0	1,739.1
Lease obligations [Abstract]
Current operating lease liabilities	0.8	0.6
Long-term operating lease liabilities	9.4	7.8
Current portion of finance lease obligations	87.8	112.3
Long-term finance lease liabilities	2,752.2	2,702.3
Accumulated amortization	$ 1,483.8	$ 1,509.7
Operating Lease, Right-of-Use Asset, Statement of Financial Position [Extensible Enumeration]	Other Assets, Noncurrent	Other Assets, Noncurrent
Finance Lease, Right-of-Use Asset, Statement of Financial Position [Extensible Enumeration]	Property, Plant and Equipment, Net	Property, Plant and Equipment, Net
Operating lease, liability, current [Extensible Enumeration]	Other Liabilities, Current	Other Liabilities, Current
Operating lease liability, noncurrent [Extensible Enumeration]	Other Liabilities, Noncurrent	Other Liabilities, Noncurrent
Power purchase commitment
Right of use assets [Abstract]
Finance lease right of use assets, net	$ 0.0	$ 38.3
Lease obligations [Abstract]
Current portion of finance lease obligations	0.0	36.3
Port Washington Generating Station
Right of use assets [Abstract]
Finance lease right of use assets, net	268.6	297.1
Lease obligations [Abstract]
Current portion of finance lease obligations	42.9	37.8
Long-term finance lease liabilities	474.8	512.2
Elm Road Generating Station
Right of use assets [Abstract]
Finance lease right of use assets, net	1,362.0	1,335.8
Lease obligations [Abstract]
Current portion of finance lease obligations	44.9	38.2
Long-term finance lease liabilities	2,177.8	2,118.8
Land Lease - Utility Solar Generation
Right of use assets [Abstract]
Finance lease right of use assets, net	92.4	67.9
Lease obligations [Abstract]
Current portion of finance lease obligations	0.0
Long-term finance lease liabilities	$ 99.6	$ 71.3

XML

Leases - Future Minimum Lease Payments (Details) - USD ($) $ in Millions	Dec. 31, 2023	Dec. 31, 2022
Total operating leases
2024	$ 1.3
2025	1.0
2026	1.0
2027	0.7
2028	0.5
Thereafter	13.9
Total minimum lease payments	18.4
Less: interest	(8.2)
Present value of minimum lease payments	10.2
Less: short-term lease liabilities	(0.8)	$ (0.6)
Long-term operating lease liabilities	9.4	7.8
Total finance leases
2024	420.2
2025	420.9
2026	420.9
2027	420.6
2028	420.6
Thereafter	4,263.7
Total minimum lease payments	6,366.9
Less: interest	(3,526.9)
Present value of minimum lease payments	2,840.0
Less: short-term lease liabilities	(87.8)	(112.3)
Finance lease obligations	2,752.2	2,702.3
Port Washington Generating Station
Total finance leases
2024	102.8
2025	102.5
2026	102.4
2027	102.2
2028	102.2
Thereafter	302.0
Total minimum lease payments	814.1
Less: interest	(296.4)
Present value of minimum lease payments	517.7
Less: short-term lease liabilities	(42.9)	(37.8)
Finance lease obligations	474.8	512.2
Elm Road Generating Station
Total finance leases
2024	314.0
2025	313.9
2026	313.9
2027	313.8
2028	313.7
Thereafter	3,614.2
Total minimum lease payments	5,183.5
Less: interest	(2,960.8)
Present value of minimum lease payments	2,222.7
Less: short-term lease liabilities	(44.9)	(38.2)
Finance lease obligations	2,177.8	2,118.8
Land Lease - Utility Solar Generation
Total finance leases
2024	3.4
2025	4.5
2026	4.6
2027	4.6
2028	4.7
Thereafter	347.5
Total minimum lease payments	369.3
Less: interest	(269.7)
Present value of minimum lease payments	99.6
Less: short-term lease liabilities	0.0
Finance lease obligations	$ 99.6	$ 71.3

XML

Income Taxes - Summary of income tax expense (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Income Tax Disclosure [Abstract]
Current tax expense	$ 122.0	$ 81.0	$ 90.3
Deferred income taxes, net	26.2	53.6	(30.7)
ITCs	(5.5)	(1.5)	(1.5)
Total income tax expense	$ 142.7	$ 133.1	$ 58.1

XML

Income Taxes - Statutory rate reconciliation (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021	Jan. 01, 2020
Effective Income Tax Rate Reconciliation, Amount [Abstract]
Statutory federal income tax	$ 130.9	$ 111.2	$ 92.3
State income taxes net of federal tax benefit	37.4	33.1	28.2
Federal excess deferred tax amortization	(20.8)	(23.2)	(23.2)
PTCs	(11.6)	(2.3)	(6.8)
AFUDC - Equity	(8.6)	(3.9)	(1.7)
Domestic production activities deferral	6.3	6.3	6.3
Federal excess deferred tax amortization - Wisconsin unprotected	5.3	5.3	(42.7)
Other, net	3.8	6.6	5.7
Total income tax expense	$ 142.7	$ 133.1	$ 58.1
Effective Income Tax Rate Reconciliation, Percentage [Abstract]
Statutory federal income tax	21.00%	21.00%	21.00%
State income taxes net of federal tax benefit	6.00%	6.30%	6.40%
Federal excess deferred tax amortization	(3.30%)	(4.40%)	(5.30%)
PTCs	(1.90%)	(0.40%)	(1.50%)
AFUDC - Equity	(1.40%)	(0.70%)	(0.40%)
Domestic production activities deferral	1.00%	1.10%	1.40%
Federal excess deferred tax amortization - Wisconsin unprotected	0.90%	1.00%	(9.70%)
Other, net	0.60%	1.20%	1.30%
Total income tax expense	22.90%	25.10%	13.20%
2018 and 2019 rates | Public Service Commission of Wisconsin (PSCW) | Tax Cuts and Jobs Act of 2017
Income Taxes
Income statement impact of amortizing protected tax benefits	$ 0.0	$ 0.0	$ 0.0
2020 and 2021 rates | Public Service Commission of Wisconsin (PSCW) | Tax Cuts and Jobs Act of 2017
Income Taxes
Income statement impact of amortizing unprotected tax benefits	$ 0.0	$ 0.0	$ 0.0
2020 and 2021 rates | Public Service Commission of Wisconsin (PSCW) | Electric rates | Tax Cuts and Jobs Act of 2017
Income Taxes
Amortization period				2 years
2020 and 2021 rates | Public Service Commission of Wisconsin (PSCW) | Natural gas rates | Tax Cuts and Jobs Act of 2017
Income Taxes
Amortization period				4 years

XML

Income Taxes - Components of deferred income taxes (Details) - USD ($) $ in Millions	Dec. 31, 2023	Dec. 31, 2022
Deferred Tax Assets
Tax gross up - regulatory items	$ 103.4	$ 110.3
Deferred revenues	103.9	106.5
Future tax benefits	7.1	10.1
Other	53.6	60.2
Total deferred tax assets	268.0	287.1
Non-current
Property-related	1,430.4	1,399.0
Deferred costs - plant retirements	186.2	198.0
Employee benefits and compensation	60.6	68.2
Deferred costs - SSR	37.5	40.9
Other	66.8	48.3
Total deferred tax liabilities	1,781.5	1,754.4
Deferred tax liability, net	$ 1,513.5	$ 1,467.3

XML

Income Taxes - Summary of Operating Loss Carryforwards (Details) - USD ($) $ in Millions	Dec. 31, 2023	Dec. 31, 2022
Income Taxes
Balance of tax benefit carryforwards, gross	$ 0.0	$ 0.0
Balance of tax benefit carryforwards, deferred tax effect	7.1	10.1
Federal Tax Jurisdiction
Income Taxes
Tax credit carryforwards, gross	0.0	0.0
Tax credit carryforwards, deferred tax effect	$ 7.1	$ 10.1

XML

Income Taxes - Unrecognized Tax Benefits (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Income Tax Disclosure [Abstract]
Unrecognized tax benefits	$ 0.0	$ 0.0
Interest expense in the consolidated income statements	0.0	0.0	$ 0.0
Penalties in the consolidated income statements	0.0	0.0	$ 0.0
Accrued interest on the consolidated balance sheets	0.0	0.0
Accrued penalties on the consolidated balance sheets	$ 0.0	$ 0.0

XML

Fair Value Measurements - Assets and Liabilities Measured on a Recurring Basis (Details) - USD ($) $ in Millions	Dec. 31, 2023	Dec. 31, 2022
Assets
Derivative assets	$ 4.7	$ 38.8
Liabilities
Derivative liabilities	38.5	30.0
Fair value measurements on a recurring basis
Assets
Derivative assets	4.7	38.8
Liabilities
Derivative liabilities	38.5
Fair value measurements on a recurring basis | Level 1
Assets
Derivative assets	0.9	1.6
Liabilities
Derivative liabilities	16.1
Fair value measurements on a recurring basis | Level 2
Assets
Derivative assets	1.3	35.2
Liabilities
Derivative liabilities	22.4
Fair value measurements on a recurring basis | Level 3
Assets
Derivative assets	2.5	2.0
Liabilities
Derivative liabilities	0.0
Fair value measurements on a recurring basis | Natural gas contracts
Assets
Derivative assets	2.2	4.1
Liabilities
Derivative liabilities	19.2	30.0
Fair value measurements on a recurring basis | Natural gas contracts | Level 1
Assets
Derivative assets	0.9	1.6
Liabilities
Derivative liabilities	16.1	29.3
Fair value measurements on a recurring basis | Natural gas contracts | Level 2
Assets
Derivative assets	1.3	2.5
Liabilities
Derivative liabilities	3.1	0.7
Fair value measurements on a recurring basis | Natural gas contracts | Level 3
Assets
Derivative assets	0.0	0.0
Liabilities
Derivative liabilities	0.0	0.0
Fair value measurements on a recurring basis | FTRs
Assets
Derivative assets	2.5	2.0
Fair value measurements on a recurring basis | FTRs | Level 1
Assets
Derivative assets	0.0	0.0
Fair value measurements on a recurring basis | FTRs | Level 2
Assets
Derivative assets	0.0	0.0
Fair value measurements on a recurring basis | FTRs | Level 3
Assets
Derivative assets	2.5	2.0
Fair value measurements on a recurring basis | Coal contracts
Assets
Derivative assets		32.7
Liabilities
Derivative liabilities	19.3
Fair value measurements on a recurring basis | Coal contracts | Level 1
Assets
Derivative assets		0.0
Liabilities
Derivative liabilities	0.0
Fair value measurements on a recurring basis | Coal contracts | Level 2
Assets
Derivative assets		32.7
Liabilities
Derivative liabilities	19.3
Fair value measurements on a recurring basis | Coal contracts | Level 3
Assets
Derivative assets		$ 0.0
Liabilities
Derivative liabilities	$ 0.0

XML

Fair Value Measurements - Level 3 Reconciliation (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Level 3 rollforward
Balance at the beginning of the period	$ 2.0	$ 1.0	$ 1.1
Purchases	8.1	7.6	3.1
Settlements	(7.6)	(6.6)	(3.2)
Balance at the end of the period	$ 2.5	$ 2.0	$ 1.0

XML

Fair Value Measurements - Financial Instruments (Details) - USD ($) $ in Millions	Dec. 31, 2023	Dec. 31, 2022
Financial instruments
Preferred stock	$ 30.4	$ 30.4
Long-term debt, including current portion	3,354.4	3,360.4
Carrying amount
Financial instruments
Preferred stock	30.4	30.4
Long-term debt, including current portion	3,354.4	3,360.4
Fair value
Financial instruments
Preferred stock	21.4	22.7
Long-term debt, including current portion	$ 3,255.4	$ 3,143.2

XML

Derivative Instruments - Derivative Assets and Derivative Liabilities (Details) $ in Millions	Dec. 31, 2023 USD ($) Instruments	Dec. 31, 2022 USD ($) Instruments
Derivative assets
Current derivative assets	$ 4.7	$ 23.7
Long-term derivative assets	0.0	15.1
Total derivative assets	$ 4.7	$ 38.8
Current derivative assets balance sheet location	Other	Other
Long-term derivative assets balance sheet location	Other Assets, Noncurrent	Other Assets, Noncurrent
Derivative liabilities
Current derivative liabilities	$ 28.8	$ 28.8
Long-term derivative liabilities	9.7	1.2
Total derivative liabilities	$ 38.5	$ 30.0
Current derivative liabilities balance sheet location	Other Liabilities, Current	Other Liabilities, Current
Long-term derivative liabilities balance sheet location	Other Liabilities, Noncurrent	Other Liabilities, Noncurrent
Natural gas contracts
Derivative assets
Current derivative assets	$ 2.2	$ 4.1
Long-term derivative assets	0.0	0.0
Derivative liabilities
Current derivative liabilities	18.6	28.8
Long-term derivative liabilities	0.6	1.2
FTRs
Derivative assets
Current derivative assets	2.5	2.0
Derivative liabilities
Current derivative liabilities	0.0	0.0
Coal contracts
Derivative assets
Current derivative assets	0.0	17.6
Long-term derivative assets	0.0	15.1
Derivative liabilities
Current derivative liabilities	10.2	0.0
Long-term derivative liabilities	$ 9.1	$ 0.0
Derivatives designated as hedging instruments
Derivative instruments
Number of derivative instruments | Instruments	0	0

XML

Derivative Instruments - Gains (Losses) and Notional Volumes (Details) MWh in Millions, MMBTU in Millions, $ in Millions	12 Months Ended
	Dec. 31, 2023 USD ($) MWh MMBTU	Dec. 31, 2022 USD ($) MWh MMBTU	Dec. 31, 2021 USD ($) MWh MMBTU
Realized gains (losses) on derivatives
Gains (losses)	$ (87.7)	$ 94.7	$ 59.5
Realized gains and losses on derivatives income statement location	Cost of sales	Cost of sales	Cost of sales
Natural gas contracts
Realized gains (losses) on derivatives
Gains (losses)	$ (102.2)	$ 86.6	$ 50.8
Notional sales volumes
Notional sales volumes | MMBTU	68.5	59.7	69.2
FTRs
Realized gains (losses) on derivatives
Gains (losses)	$ 14.5	$ 8.1	$ 8.7
Notional sales volumes
Notional sales volumes | MWh	20.4	18.9	21.0

XML

Derivative Instruments - Balance Sheet Offsetting (Details) - USD ($) $ in Millions	Dec. 31, 2023	Dec. 31, 2022
Cash collateral
Cash collateral posted	$ 26.7	$ 46.7
Offsetting derivative assets
Gross amount recognized on the balance sheet	4.7	38.8
Gross amount not offset on the balance sheet	(1.3)	(1.8)
Net amount	3.4	37.0
Offsetting derivative liabilities
Gross amount recognized on the balance sheet	38.5	30.0
Gross amount not offset on the balance sheet	(16.5)	(29.5)
Net amount	22.0	0.5
Cash collateral posted	$ 15.2	$ 27.7

XML

Employee Benefits - Change in Benefit Obligations and Plan Assets (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Pension Benefits
Change in benefit obligation
Obligation at January 1	$ 894.9	$ 1,144.0
Service cost	10.3	13.4	$ 14.4
Interest cost	47.1	32.6	31.1
Participant contributions	0.0	0.0
Net transfer from/to affiliates	(1.2)	4.7
Actuarial (gain) loss	29.1	(211.3)
Benefit payments	(79.4)	(88.5)
Transfer	0.0	0.0
Obligation at December 31	900.8	894.9	1,144.0
Change in fair value of plan assets
Beginning balance at January 1	940.7	1,136.9
Actual return on plan assets	68.9	(115.8)
Employer contributions net of plan transfer	3.2	3.8
Participant contributions	0.0	0.0
Net transfer from/to affiliates	(1.2)	4.3
Benefit payments	(79.4)	(88.5)
Ending balance at December 31	932.2	940.7	1,136.9
Funded status at December 31	31.4	45.8
OPEB Benefits
Change in benefit obligation
Obligation at January 1	144.6	190.6
Service cost	2.6	3.9	4.3
Interest cost	7.7	5.6	5.3
Participant contributions	5.6	6.6
Net transfer from/to affiliates	(0.4)	0.0
Actuarial (gain) loss	19.5	(46.9)
Benefit payments	(18.7)	(19.0)
Federal subsidy on benefits paid	1.3	1.2
Transfer	1.2	2.6
Obligation at December 31	163.4	144.6	190.6
Change in fair value of plan assets
Beginning balance at January 1	211.3	255.7
Actual return on plan assets	17.7	(32.6)
Employer contributions net of plan transfer	42.9	0.1
Participant contributions	5.6	6.6
Net transfer from/to affiliates	(0.2)	0.5
Benefit payments	(18.7)	(19.0)
Ending balance at December 31	172.8	211.3	$ 255.7
Funded status at December 31	9.4	$ 66.7
Amount transferred out of WEC Energy Group Retiree Welfare Plan	$ 43.0

XML

Employee Benefits - Amounts Recognized on the Balance Sheets (Details) - USD ($) $ in Millions	Dec. 31, 2023	Dec. 31, 2022
Defined Benefit Plan Disclosure [Line Items]
Pension and OPEB assets	$ 71.0	$ 143.3
Pension Benefits
Defined Benefit Plan Disclosure [Line Items]
Pension and OPEB assets	61.6	76.6
Other long-term liabilities	30.2	30.8
Total net assets	31.4	45.8
OPEB Benefits
Defined Benefit Plan Disclosure [Line Items]
Pension and OPEB assets	9.4	66.7
Other long-term liabilities	0.0	0.0
Total net assets	$ 9.4	$ 66.7

XML

Employee Benefits - Accumulated Benefit Obligations (Details) - Pension Plan - USD ($) $ in Millions	Dec. 31, 2023	Dec. 31, 2022
Defined Benefit Plan Disclosure [Line Items]
Accumulated benefit obligation	$ 900.0	$ 894.0
Information for pension plans with an accumulated benefit obligation in excess of plan assets
Accumulated benefit obligation	30.0	30.6
Fair value of plan assets	0.0	0.0
Information for pension plans with a projected benefit obligation in excess of plan assets
Projected benefit obligation	30.2	30.8
Fair value of plan assets	$ 0.0	$ 0.0

XML

Employee Benefits - Amounts Not Yet Recognized in Net Periodic Benefit Cost (Details) - USD ($) $ in Millions	Dec. 31, 2023	Dec. 31, 2022
Pension Benefits
Net regulatory assets (liabilities)
Net actuarial loss (gain)	$ 342.1	$ 326.7
Prior service credits	(1.9)	(2.0)
Total	340.2	324.7
OPEB Benefits
Net regulatory assets (liabilities)
Net actuarial loss (gain)	(89.1)	(113.0)
Prior service credits	(0.4)	(1.3)
Total	$ (89.5)	$ (114.3)

XML

Employee Benefits - Net Periodic Benefit Cost (Credit) (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Components of net periodic benefit cost (credit) (including amounts capitalized to the balance sheets)
Regulatory liabilities	$ 1,636.7	$ 1,638.8
Regulatory assets	2,860.7	2,817.5
Pension Benefits
Components of net periodic benefit cost (credit) (including amounts capitalized to the balance sheets)
Service cost	10.3	13.4	$ 14.4
Interest cost	47.1	32.6	31.1
Expected return on plan assets	(64.3)	(71.4)	(70.3)
Amortization of prior service credit	(0.1)	(0.1)	(0.1)
Amortization of net actuarial loss (gain)	9.2	29.8	41.9
Net periodic benefit cost (credit)	2.2	4.3	17.0
Pension Benefits | Pension and Other Postretirement Plans Cost
Components of net periodic benefit cost (credit) (including amounts capitalized to the balance sheets)
Regulatory liabilities	1.2
OPEB Benefits
Components of net periodic benefit cost (credit) (including amounts capitalized to the balance sheets)
Service cost	2.6	3.9	4.3
Interest cost	7.7	5.6	5.3
Expected return on plan assets	(13.4)	(17.7)	(16.9)
Amortization of prior service credit	(0.9)	(1.3)	(1.2)
Amortization of net actuarial loss (gain)	(8.7)	(12.1)	(10.9)
Net periodic benefit cost (credit)	(12.7)	$ (21.6)	$ (19.4)
OPEB Benefits | Pension and Other Postretirement Plans Cost
Components of net periodic benefit cost (credit) (including amounts capitalized to the balance sheets)
Regulatory assets	$ 5.3

XML

Employee Benefits - Assumptions (Details)	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Pension Benefits | Benefit obligation assumptions
Weighted average assumptions - benefit obligations
Discount rate		5.20%	5.50%	2.94%
Rate of compensation increase		4.00%	4.00%
Interest credit rate		5.14%	5.14%
Pension Benefits | Net periodic benefit cost assumptions
Weighted average assumptions - net periodic benefit cost
Discount rate		5.50%	2.94%	2.63%
Expected return on plan assets		6.50%	6.75%	6.75%
Rate of compensation increase		4.00%	4.00%	4.00%
Interest credit rate		5.14%	5.16%	5.16%
Pension Benefits | Net periodic benefit cost assumptions | Subsequent event
Weighted average assumptions - net periodic benefit cost
Expected return on plan assets	6.50%
OPEB Benefits | Benefit obligation assumptions
Weighted average assumptions - benefit obligations
Discount rate		5.15%	5.50%	2.95%
OPEB Benefits | Benefit obligation assumptions | Pre 65
Medical cost trend rates
Assumed medical cost trend rate		6.25%	6.50%
Ultimate trend rate		5.00%	5.00%
Year ultimate trend rate is reached		2031	2031
OPEB Benefits | Benefit obligation assumptions | Post 65
Medical cost trend rates
Assumed medical cost trend rate		6.55%	6.00%
Ultimate trend rate		5.00%	5.00%
Year ultimate trend rate is reached		2030	2031
OPEB Benefits | Net periodic benefit cost assumptions
Weighted average assumptions - net periodic benefit cost
Discount rate		5.50%	2.95%	2.65%
Expected return on plan assets		6.50%	7.00%	7.00%
OPEB Benefits | Net periodic benefit cost assumptions | Subsequent event
Weighted average assumptions - net periodic benefit cost
Expected return on plan assets	6.50%
OPEB Benefits | Net periodic benefit cost assumptions | Pre 65
Medical cost trend rates
Assumed medical cost trend rate		6.50%	5.70%	5.85%
Ultimate trend rate		5.00%	5.00%	5.00%
Year ultimate trend rate is reached		2031	2028	2028
OPEB Benefits | Net periodic benefit cost assumptions | Post 65
Medical cost trend rates
Assumed medical cost trend rate		6.00%	5.72%	5.86%
Ultimate trend rate		5.00%	5.00%	5.00%
Year ultimate trend rate is reached		2031	2028	2028

XML

Employee Benefits - Target Asset Allocations (Details)	Dec. 31, 2023
Pension Plan | Equity securities
Defined Benefit Plan Disclosure [Line Items]
Target asset allocations (as a percent)	25.00%
Pension Plan | Fixed income securities
Defined Benefit Plan Disclosure [Line Items]
Target asset allocations (as a percent)	55.00%
Pension Plan | Private equity and real estate
Defined Benefit Plan Disclosure [Line Items]
Target asset allocations (as a percent)	20.00%
OPEB Plan | Equity securities
Defined Benefit Plan Disclosure [Line Items]
Target asset allocations (as a percent)	45.00%
OPEB Plan | Fixed income securities
Defined Benefit Plan Disclosure [Line Items]
Target asset allocations (as a percent)	45.00%
OPEB Plan | Real estate investments
Defined Benefit Plan Disclosure [Line Items]
Target asset allocations (as a percent)	10.00%

XML

Employee Benefits - Plan Assets (Details) - USD ($) $ in Millions	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Pension Plan
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets	$ 932.2	$ 940.7	$ 1,136.9
Pension Plan | Level 1, 2, and 3
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets	544.6	585.0
Pension Plan | Level 1, 2, and 3 | United States equity
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets	57.4	69.5
Pension Plan | Level 1, 2, and 3 | International equity
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets	51.4	60.8
Pension Plan | Level 1, 2, and 3 | United States bonds
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets	404.1	419.2
Pension Plan | Level 1, 2, and 3 | International bonds
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets	31.7	35.5
Pension Plan | Level 1
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets	108.8	130.3
Pension Plan | Level 1 | United States equity
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets	57.4	69.5
Pension Plan | Level 1 | International equity
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets	51.4	60.8
Pension Plan | Level 1 | United States bonds
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets	0.0	0.0
Pension Plan | Level 1 | International bonds
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets	0.0	0.0
Pension Plan | Level 2
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets	435.8	454.7
Pension Plan | Level 2 | United States equity
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets	0.0	0.0
Pension Plan | Level 2 | International equity
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets	0.0	0.0
Pension Plan | Level 2 | United States bonds
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets	404.1	419.2
Pension Plan | Level 2 | International bonds
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets	31.7	35.5
Pension Plan | Level 3
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets	0.0	0.0
Pension Plan | Level 3 | United States equity
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets	0.0	0.0
Pension Plan | Level 3 | International equity
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets	0.0	0.0
Pension Plan | Level 3 | United States bonds
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets	0.0	0.0
Pension Plan | Level 3 | International bonds
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets	0.0	0.0
Pension Plan | Investments measured at net asset value per share | Equity securities
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets	137.9	139.7
Pension Plan | Investments measured at net asset value per share | Fixed income securities
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets	0.1	0.0
Pension Plan | Investments measured at net asset value per share | Other investments
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets	249.6	216.0
OPEB Plan
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets	172.8	211.3	$ 255.7
OPEB Plan | Level 1, 2, and 3
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets	102.7	119.3
OPEB Plan | Level 1, 2, and 3 | United States equity
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets	17.3	23.6
OPEB Plan | Level 1, 2, and 3 | International equity
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets	16.3	20.2
OPEB Plan | Level 1, 2, and 3 | United States bonds
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets	65.8	71.6
OPEB Plan | Level 1, 2, and 3 | International bonds
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets	3.3	3.9
OPEB Plan | Level 1
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets	47.0	69.6
OPEB Plan | Level 1 | United States equity
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets	17.3	23.6
OPEB Plan | Level 1 | International equity
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets	16.3	20.2
OPEB Plan | Level 1 | United States bonds
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets	13.4	25.8
OPEB Plan | Level 1 | International bonds
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets	0.0	0.0
OPEB Plan | Level 2
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets	55.7	49.7
OPEB Plan | Level 2 | United States equity
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets	0.0	0.0
OPEB Plan | Level 2 | International equity
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets	0.0	0.0
OPEB Plan | Level 2 | United States bonds
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets	52.4	45.8
OPEB Plan | Level 2 | International bonds
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets	3.3	3.9
OPEB Plan | Level 3
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets	0.0	0.0
OPEB Plan | Level 3 | United States equity
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets	0.0	0.0
OPEB Plan | Level 3 | International equity
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets	0.0	0.0
OPEB Plan | Level 3 | United States bonds
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets	0.0	0.0
OPEB Plan | Level 3 | International bonds
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets	0.0	0.0
OPEB Plan | Investments measured at net asset value per share | Equity securities
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets	34.4	47.3
OPEB Plan | Investments measured at net asset value per share | Fixed income securities
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets	6.3	12.7
OPEB Plan | Investments measured at net asset value per share | Other investments
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets	$ 29.4	$ 32.0

XML

Employee Benefits - Cash Flows (Details) $ in Millions	Dec. 31, 2023 USD ($)
Pension Benefits
Defined Benefit Plan Disclosure [Line Items]
Expected contributions to the plans during the next year	$ 3.2
2024	86.9
2025	80.3
2026	79.6
2027	76.0
2028	73.4
2029 through 2033	331.3
OPEB Benefits
Defined Benefit Plan Disclosure [Line Items]
Expected contributions to the plans during the next year	0.2
2024	11.5
2025	11.3
2026	11.3
2027	11.5
2028	11.6
2029 through 2033	$ 58.9

XML

Employee Benefits - Defined Contribution Benefit Plans (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Retirement Benefits [Abstract]
Total costs incurred for defined contribution benefit plans	$ 15.5	$ 14.2	$ 12.3

XML

Segment Information (Details) $ in Millions	12 Months Ended
	Dec. 31, 2023 USD ($) numberOfSegments	Dec. 31, 2022 USD ($)	Dec. 31, 2021 USD ($)
Segment Reporting [Abstract]
Number of reportable segments | numberOfSegments	2
Significant items reported in the other segment | $	$ 0.0	$ 0.0	$ 0.0

XML

Variable Interest Entities - WEPCo Environmental Trust (Details) - USD ($) $ in Millions	1 Months Ended
	Nov. 30, 2020	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Assets
Other current assets (restricted cash)		$ 0.8	$ 3.0	$ 2.4
Regulatory assets		2,860.7	2,817.5
Other long-term assets (restricted cash)		0.6	38.6	$ 0.6
Liabilities
Current portion of long-term debt		309.0	8.9
Long-term debt		3,045.4	3,351.5
WEPCo Environmental Trust
Variable interest entities
Securitization of environmental control costs related to Pleasant Prairie power plant	$ 100.0
Assets
Other current assets (restricted cash)		0.8	3.0
Regulatory assets		85.9	92.4
Other long-term assets (restricted cash)		0.6	0.6
Liabilities
Current portion of long-term debt		9.0	8.9
Other current liabilities (accrued interest)		0.1	0.1
Long-term debt		$ 85.3	$ 94.1

XML

Variable Interest Entities - Power Purchase Commitment (Details) $ in Millions	Jan. 01, 2023 USD ($)	May 31, 2022 MW
Whitewater
Variable interest entities
Ownership (as a percentage)	50.00%
Power purchase commitment
Variable interest entities
Firm capacity from power purchase agreement (in megawatts) | MW		236.5
Residual guarantee associated with power purchase agreement | $	$ 0.0

XML

Commitments and Contingencies - Unconditional Purchase Obligations (Details) $ in Millions	Dec. 31, 2023 USD ($)
Minimum future commitments for purchase obligations
Total Amounts Committed	$ 7,125.5
2024	920.0
2025	770.9
2026	730.0
2027	761.4
2028	810.2
Later Years	3,133.0
Nuclear | Electric
Minimum future commitments for purchase obligations
Total Amounts Committed	6,280.6
2024	600.3
2025	634.5
2026	681.6
2027	730.4
2028	782.6
Later Years	2,851.2
Coal supply and transportation | Electric
Minimum future commitments for purchase obligations
Total Amounts Committed	354.9
2024	247.9
2025	94.2
2026	12.8
2027	0.0
2028	0.0
Later Years	0.0
Purchased power | Electric
Minimum future commitments for purchase obligations
Total Amounts Committed	29.2
2024	3.6
2025	2.3
2026	2.4
2027	2.4
2028	2.5
Later Years	16.0
Natural gas utility supply and transportation | Natural gas
Minimum future commitments for purchase obligations
Total Amounts Committed	460.8
2024	68.2
2025	39.9
2026	33.2
2027	28.6
2028	25.1
Later Years	$ 265.8

XML

Commitments and Contingencies - Environmental Matters (Details) $ in Millions	1 Months Ended							12 Months Ended
	Oct. 31, 2023 mo States	Aug. 31, 2023	May 31, 2023 MW performance_obligations	Apr. 30, 2023 MMBTU	Jan. 31, 2023 micrograms	May 31, 2021	Dec. 31, 2020 micrograms performance_obligations	Dec. 31, 2023 USD ($) MW generating_units performance_obligations	Feb. 07, 2024 micrograms	Dec. 31, 2022 USD ($)	Dec. 31, 2021 USD ($)
Manufactured Gas Plant Remediation
Regulatory assets | $								$ 2,860.7		$ 2,817.5
Reserves for future environmental remediation								Other Liabilities, Noncurrent		Other Liabilities, Noncurrent
Cross State Air Pollution Rule | Electric | Maximum
Air Quality
RICE unit megawatts | MW								25
Mercury and Air Toxics Standards | Electric
Air Quality
Current level of particulate matter in pounds per million british thermal unit | MMBTU				0.03
EPA proposed lower limit for particulate matter | MMBTU				0.01
Even lower level of particulate matter that the EPA is seeking opinions on | MMBTU				0.006
National Ambient Air Quality Standards | Electric
Air Quality
Number of states that failed to submit timely SIP revisions to address nonattainment areas classified as "moderate" for the 2015 standard | States	11
Number of months before offset sanctions take effect if the SIP is not approved | mo	18
Number of revisions necessary to the 2012 standard for particulate matter | performance_obligations							0
Current level of micrograms per cubic meter that particulate matter needs to be below | micrograms							12
Current micrograms per cubic meter under the 24-hour standard that particulate matter needs to be below | micrograms							35
National Ambient Air Quality Standards | Electric | Minimum
Air Quality
Period of time for EPA review of ozone plan		3 years
Proposed primary (health-based) annual standard | micrograms					9
The EPA is taking comments on this full range of micrograms per cubic meter | micrograms					8
National Ambient Air Quality Standards | Electric | Maximum
Air Quality
Period of time for EPA review of ozone plan		5 years
Proposed primary (health-based) annual standard | micrograms					10
The EPA is taking comments on this full range of micrograms per cubic meter | micrograms					11
National Ambient Air Quality Standards | Electric | Maximum | Subsequent event
Air Quality
New primary annual PM2.5 level | micrograms									9
Climate Change | Electric
Air Quality
Number of applicable GHG performance standards for coal plants | performance_obligations			0
Percent capacity factor that if combined cycle natural gas plants are above it causes the rule to be highly dependent on hydrogen or carbon capture			50.00%
Percent capacity factor for simple cycle natural gas fired combustion turbines that there are no applicable limits if the capacity factor is less than this			20.00%
Rules that are being proposed for natural gas-fired stationary combustion turbines | performance_obligations			1
Number of subcategories of combustion turbine unit annual capacity factors that the proposed rule will be broken up into | performance_obligations			3
Capacity of coal generation retired, in megawatts | MW								1,500
Capacity of fossil-fueled generation to be retired by the end of 2031, in megawatts | MW								1,800
Company goal for percentage of carbon dioxide emission reduction by the end of 2025						60.00%
Company goal for percentage of carbon dioxide emissions reduction below 2005 levels by the end of 2030						80.00%
Climate Change | Electric | Maximum
Air Quality
RICE unit megawatts | MW			25
Clean Water Act Cooling Water Intake Structure Rule | Electric
Water Quality
Number of generating units that may be retired | generating_units								4
Steam Electric Effluent Guidelines | Electric
Water Quality
Number of new ELG rule requirements that affect us | performance_obligations								2
Capital investment that was required to achieve discharge limits | $								$ 97.0
Steam Electric Effluent Guidelines | Electric | OCPP Units 7 and 8 Owned by WE
Water Quality
Capital investment that was required to achieve discharge limits | $											$ 8.0
Steam Electric Effluent Guidelines | Electric | Elm Road Generating Station
Water Quality
Capital investment that was required to achieve discharge limits | $											$ 89.0
Biological treatment center costs placed in service at ERGS | $								89.0
Manufactured Gas Plant Remediation | Natural gas
Manufactured Gas Plant Remediation
Reserves for future environmental remediation | $								10.3		$ 10.3
Manufactured Gas Plant Remediation | Natural gas | Environmental remediation costs
Manufactured Gas Plant Remediation
Regulatory assets | $								$ 12.2		$ 14.6
Renewables, Efficiency, and Conservation | Electric | Wisconsin
Renewables, Efficiency, and Conservation
Annual state renewable portfolio requirement, as a percent								10.00%
Required renewable energy percent achieved								8.27%
Percent of annual operating revenues used to fund renewable program								1.20%

XML

Supplemental Cash Flow Information (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Additional Cash Flow Elements and Supplemental Cash Flow Information [Abstract]
Cash paid for interest, net of amount capitalized	$ 463.8	$ 449.2	$ 460.8
Cash paid for income taxes, net	99.1	88.0	88.0
Cash received for sale of PTCs to a third party	4.9
Significant non-cash investing and financing transactions
Accounts payable related to construction costs	71.8	89.1	42.4
Increase in receivables related to insurance proceeds	0.0	0.0	37.3
Liabilities accrued for software licensing agreement	$ 0.0	$ 3.1	$ 0.0

XML

Supplemental Cash Flow Information - Reconciliation of Cash, Cash Equivalents, and Restricted Cash (Details) - USD ($) $ in Millions	Dec. 31, 2023	Jan. 01, 2023	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Reconciliation of cash, cash equivalents, and restricted cash
Cash and cash equivalents	$ 6.1		$ 6.1	$ 0.0
Restricted cash included in other current assets	0.8		3.0	2.4
Restricted cash included in other long-term assets	0.6		38.6	0.6
Cash, cash equivalents, and restricted cash	$ 7.5		$ 47.7	$ 3.0	$ 7.2
Whitewater
Whitewater acquisition
Ownership (as a percentage)		50.00%

XML

Regulatory Environment - 2024 Limited Rate Case Re-Opener (Details) - Public Service Commission of Wisconsin (PSCW) - 2024 Rate Case Re-Opener $ in Millions	Dec. 20, 2023 USD ($)
Electric
Public Utilities, General Disclosures
Approved rate increase	$ 82.2
Approved rate increase (as a percent)	2.50%
Natural gas
Public Utilities, General Disclosures
Approved rate increase	$ 23.9
Approved rate increase (as a percent)	4.50%

XML

Regulatory Environment - 2023 and 2024 Rates (Details) - Public Service Commission of Wisconsin (PSCW) - 2023 and 2024 Rates	1 Months Ended
	Dec. 31, 2022 USD ($)
Public Utilities, General Disclosures
Approved return on equity (as a percent)	9.80%
Approved common equity component average (as a percent)	53.00%
Percentage of first 15 basis points of additional earnings retained by the utility	100.00%
Return on equity in excess of authorized amount (as a percent)	0.15%
Percentage of additional earnings between 15 and 75 basis points refunded to customers	50.00%
Return on equity in excess of first 15 basis points above authorized amount (as a percent)	0.60%
Percentage of earnings in excess of 75 basis points refunded to customers	100.00%
Decrease in certain customer fixed charges	$ 1.00
Commitments to contribute to Keep Wisconsin Warm Fund	4,000,000
Electric
Public Utilities, General Disclosures
Approved rate increase	$ 283,500,000
Approved rate increase (as a percent)	9.10%
Natural gas
Public Utilities, General Disclosures
Approved rate increase	$ 46,100,000
Approved rate increase (as a percent)	9.60%
Steam
Public Utilities, General Disclosures
Approved rate increase	$ 7,600,000
Approved rate increase (as a percent)	35.30%

XML

Regulatory Environment - 2022 Rates (Details) - Public Service Commission of Wisconsin (PSCW) - 2022 Rates	1 Months Ended
	Sep. 30, 2021
Public Utilities, General Disclosures
Period to forego filing a rate case	1 year
Percentage of first 15 basis points of additional earnings retained by the utility	100.00%
Return on equity in excess of authorized amount (as a percent)	0.15%

XML

Regulatory Environment - 2020 and 2021 Rates (Details) - USD ($) $ in Millions	1 Months Ended
	May 31, 2021	Dec. 31, 2019	Dec. 31, 2023
WEPCo Environmental Trust Bonds 1.578%, due 2035
Public Utilities, General Disclosures
Interest rate			1.578%
Public Service Commission of Wisconsin (PSCW) | WEPCo Environmental Trust Finance I, LLC | Electric | WEPCo Environmental Trust Bonds 1.578%, due 2035
Public Utilities, General Disclosures
Proceeds from issuance of debt	$ 118.8
Interest rate	1.578%
Public Service Commission of Wisconsin (PSCW) | 2020 and 2021 rates
Public Utilities, General Disclosures
Approved return on equity (as a percent)		10.00%
Approved common equity component average (as a percent)		52.50%
Percentage of first 25 basis points of additional earnings retained by the utility		100.00%
Return on equity in excess of authorized amount (as a percent)		0.25%
Percentage of additional earnings between 25 and 75 basis points refunded to customers		50.00%
Return on equity in excess of first 25 basis points above authorized amount (as a percent)		0.50%
Percentage of earnings in excess of 75 basis points refunded to customers		100.00%
Public Service Commission of Wisconsin (PSCW) | 2020 and 2021 rates | Electric
Public Utilities, General Disclosures
Approved rate increase		$ 15.3
Approved rate increase (as a percent)		0.50%
Pleasant Prairie power plant's book value to be securitized		$ 100.0
Public Service Commission of Wisconsin (PSCW) | 2020 and 2021 rates | Electric | Tax Cuts and Jobs Act of 2017
Public Utilities, General Disclosures
Amortization period		2 years
Public Service Commission of Wisconsin (PSCW) | 2020 and 2021 rates | Natural gas
Public Utilities, General Disclosures
Approved rate increase		$ 10.4
Approved rate increase (as a percent)		2.80%
Public Service Commission of Wisconsin (PSCW) | 2020 and 2021 rates | Natural gas | Tax Cuts and Jobs Act of 2017
Public Utilities, General Disclosures
Amortization period		4 years
Public Service Commission of Wisconsin (PSCW) | 2020 and 2021 rates | Steam
Public Utilities, General Disclosures
Approved rate increase		$ 1.9
Approved rate increase (as a percent)		8.60%
Public Service Commission of Wisconsin (PSCW) | 2020 rates | Electric | Tax Cuts and Jobs Act of 2017
Public Utilities, General Disclosures
Amortization of regulatory liabilities		$ 65.0
Public Service Commission of Wisconsin (PSCW) | 2020 rates | Natural gas | Tax Cuts and Jobs Act of 2017
Public Utilities, General Disclosures
Amortization of regulatory liabilities		(5.0)
Public Service Commission of Wisconsin (PSCW) | 2021 rates | Electric | Tax Cuts and Jobs Act of 2017
Public Utilities, General Disclosures
Amortization of regulatory liabilities		65.0
Public Service Commission of Wisconsin (PSCW) | 2021 rates | Natural gas | Tax Cuts and Jobs Act of 2017
Public Utilities, General Disclosures
Amortization of regulatory liabilities		$ (5.0)

XML

Regulatory Environment - Recovery of Natural Gas Costs (Details) - Public Service Commission of Wisconsin (PSCW) - Energy costs recoverable through rate adjustments $ in Millions	Mar. 31, 2021 USD ($)
Public Utilities, General Disclosures
Amounts recoverable from customers	$ 54
Recovery period of regulatory asset	3 months

XML

Other Income, Net (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Other Income and Expenses [Abstract]
Non-service components of net periodic benefit costs	Other income, net	Other income, net	Other income, net
AFUDC - Equity	$ 41.0	$ 18.8	$ 7.9
Non-service components of net periodic benefit costs	24.1	33.8	22.5
Other, net	3.7	(3.2)	1.7
Other income, net	$ 68.8	$ 49.4	$ 32.1

XML

Schedule II - Valuation and Qualifying Accounts (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Valuation and qualifying accounts
Balance at beginning of period	$ 49.7	$ 51.4	$ 59.3
Expense	23.8	27.3	24.8
Deferral	45.7	34.0	(0.3)
Net write-offs	(74.7)	(63.0)	(32.4)
Balance at end of period	$ 44.5	$ 49.7	$ 51.4