10-Q

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

WASHINGTON, DC 20549

FORM 10-Q

QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d)

OF THE SECURITIES EXCHANGE ACT OF 1934

For the Quarterly Period EndedMarch 31, 2018

Commission File Number	Registrant; State of Incorporation; Address; and Telephone Number	IRS Employer Identification No.
001-09057	WEC ENERGY GROUP, INC.	39-1391525
	(A Wisconsin Corporation)
	231 West Michigan Street
	P.O. Box 1331
	Milwaukee, WI 53201
	(414) 221-2345

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 [X]    No [  ]

Indicate by check mark whether the registrant has submitted electronically and posted on its corporate website, if any, every Interactive Data File required to be submitted and posted 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 and post such files).

Yes [X]    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 [X]	Accelerated filer [  ]
Non-accelerated filer [  ] (Do not check if a smaller reporting company)
	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 is a shell company (as defined in Rule 12b-2 of the Exchange Act).

Yes [  ]    No [X]

Indicate the number of shares outstanding of each of the issuer's classes of common stock, as of the latest practicable date:

Common Stock, $.01 Par Value,

315,538,808 shares outstanding at

March 31, 2018

WEC ENERGY GROUP, INC.

QUARTERLY REPORT ON FORM 10-Q

For the Quarter Ended March 31, 2018

TABLE OF CONTENTS

				Page
	CAUTIONARY STATEMENT REGARDING FORWARD-LOOKING INFORMATION			1
PART I.	FINANCIAL INFORMATION			3
ITEM 1.	FINANCIAL STATEMENTS (UNAUDITED)			3
	Condensed Consolidated Income Statements			3
	Condensed Consolidated Statements of Comprehensive Income			4
	Condensed Consolidated Balance Sheets			5
	Condensed Consolidated Statements of Cash Flows			6
	Notes to Condensed Consolidated Financial Statements			7
			Page
	Note 1	General Information	7
	Note 2	Acquisitions	7
	Note 3	Disposition	8
	Note 4	Operating Revenues	8
	Note 5	Property, Plant, and Equipment	12
	Note 6	Common Equity	13
	Note 7	Short-Term Debt and Lines of Credit	13
	Note 8	Long-Term Debt	14
	Note 9	Materials, Supplies, and Inventories	14
	Note 10	Income Taxes	14
	Note 11	Fair Value Measurements	15
	Note 12	Derivative Instruments	17
	Note 13	Guarantees	18
	Note 14	Employee Benefits	19
	Note 15	Goodwill	20
	Note 16	Investment in Transmission Affiliates	20
	Note 17	Segment Information	21
	Note 18	Variable Interest Entities	22
	Note 19	Commitments and Contingencies	23
	Note 20	Supplemental Cash Flow Information	27
	Note 21	Regulatory Environment	29
	Note 22	New Accounting Pronouncements	32
ITEM 2.	MANAGEMENT'S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND RESULTS OF OPERATIONS			33
ITEM 3.	QUANTITATIVE AND QUALITATIVE DISCLOSURES ABOUT MARKET RISK			49
ITEM 4.	CONTROLS AND PROCEDURES			50
PART II.	OTHER INFORMATION			51
ITEM 1.	LEGAL PROCEEDINGS			51
ITEM 1A.	RISK FACTORS			52
ITEM 2.	UNREGISTERED SALES OF EQUITY SECURITIES AND USE OF PROCEEDS			52
ITEM 6.	EXHIBITS			53
SIGNATURE				54

03/31/2018 Form 10-Q i WEC Energy Group, Inc.

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
ATC Holdco	ATC Holdco, LLC
Bluewater	Bluewater Natural Gas Holding, LLC
Bostco	Bostco LLC
Integrys	Integrys Holding, Inc.
MERC	Minnesota Energy Resources Corporation
MGU	Michigan Gas Utilities Corporation
NSG	North Shore Gas Company
PGL	The Peoples Gas Light and Coke Company
UMERC	Upper Michigan Energy Resources Corporation
WBS	WEC Business Services LLC
WE	Wisconsin Electric Power Company
We Power	W.E. Power, LLC
WG	Wisconsin Gas LLC
WPS	Wisconsin Public Service Corporation
Federal and State Regulatory Agencies
EPA	United States Environmental Protection Agency
FERC	Federal Energy Regulatory Commission
ICC	Illinois Commerce Commission
MDEQ	Michigan Department of Environmental Quality
MPSC	Michigan Public Service Commission
MPUC	Minnesota Public Utilities Commission
PSCW	Public Service Commission of Wisconsin
SEC	United States Securities and Exchange Commission
WDNR	Wisconsin Department of Natural Resources
Accounting Terms
AFUDC	Allowance for Funds Used During Construction
ASU	Accounting Standards Update
FASB	Financial Accounting Standards Board
GAAP	United States Generally Accepted Accounting Principles
LIFO	Last-In, First-Out
OPEB	Other Postretirement Employee Benefits
Environmental Terms
CAA	Clean Air Act
CO2	Carbon Dioxide
CPP	Clean Power Plan
GHG	Greenhouse Gas
NAAQS	National Ambient Air Quality Standards
NOV	Notice of Violation
WPDES	Wisconsin Pollutant Discharge Elimination System
Measurements
Dth	Dekatherm
MW	Megawatt
MWh	Megawatt-hour

03/31/2018 Form 10-Q ii WEC Energy Group, Inc.

Other Terms and Abbreviations
2007 Junior Notes	WEC Energy Group, Inc.'s 2007 Junior Subordinated Notes Due 2067
ALJ	Administrative Law Judge
D.C. Circuit Court of Appeals	United States Court of Appeals for the District of Columbia Circuit
ERGS	Elm Road Generating Station
Exchange Act	Securities Exchange Act of 1934, as amended
FTRs	Financial Transmission Rights
MISO	Midcontinent Independent System Operator, Inc.
MISO Energy Markets	MISO Energy and Operating Reserves Markets
OCPP	Oak Creek Power Plant
OC 5	Oak Creek Power Plant Unit 5
OC 6	Oak Creek Power Plant Unit 6
OC 7	Oak Creek Power Plant Unit 7
OC 8	Oak Creek Power Plant Unit 8
PIPP	Presque Isle Power Plant
QIP	Qualifying Infrastructure Plant
ROE	Return on Equity
SMP	Gas System Modernization Program
SMRP	System Modernization and Reliability Project
Supreme Court	United States Supreme Court
Tax Legislation	Tax Cuts and Jobs Act of 2017
VITA	Variable Income Tax Adjustment Rider

03/31/2018 Form 10-Q iii WEC Energy Group, Inc.

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 and associated compliance costs, legal proceedings, dividend payout ratios, effective tax rate, pension and OPEB plans, fuel costs, sources of electric energy supply, coal and natural gas deliveries, remediation costs, environmental matters, 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 risk factors as set forth in this report and our Annual Report on Form 10-K for the year ended December 31, 2017, 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 developments, unusual weather, 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 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, as well as the recovery of the related costs through rates;

• The impact of federal, state, and local legislative and regulatory changes, including changes in rate-setting policies or procedures, 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, and energy efficiency mandates;

• The uncertainty surrounding the recently enacted Tax Legislation, including implementing regulations and IRS interpretations, the amount to be returned to our ratepayers, and its impact, if any, on our or our subsidiaries’ credit ratings;

• Federal and state 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 permit conditions by regulatory agencies, and the recovery of associated remediation and compliance costs;

• Factors affecting the implementation of our generation reshaping plan, including related regulatory decisions, the cost of materials, supplies, and labor, and the feasibility of competing projects;

• Increased pressure on us by investors and other stakeholder groups to take more aggressive action to reduce future GHG emissions in order to limit future global temperature increases;

• The risks associated with changing commodity prices, particularly natural gas and electricity, and the availability of sources of fossil fuel, natural gas, 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;

03/31/2018 Form 10-Q 1 WEC Energy Group, Inc.

• 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, us, or any of our subsidiaries;

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

• Restrictions imposed by various financing arrangements and regulatory requirements on the ability of our subsidiaries to transfer funds to us in the form of cash dividends, loans or advances, that could prevent us from paying our common stock dividends, taxes, and other expenses, and meeting our debt obligations;

• 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 direct or indirect effect on our business resulting from terrorist attacks and cyber security 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;

• The financial performance of ATC and its corresponding contribution to our earnings, as well as the ability of ATC and Duke-American Transmission Company to obtain the required approvals for their transmission projects;

• 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 that result in competitive disadvantages and create the potential for impairment of existing assets;

• The timing, costs, and anticipated benefits associated with the remaining integration efforts relating to the Integrys acquisition;

• The risk associated with the values of goodwill and other intangible assets and their possible impairment;

• Potential business strategies to acquire and dispose of assets or businesses, which cannot be assured to be completed timely or within budgets, and legislative or regulatory restrictions or caps on non-utility acquisitions, investments or projects, including the State of Wisconsin's public utility holding company law;

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

• The ability to maintain effective internal controls in accordance with Section 404 of the Sarbanes-Oxley Act, while both integrating and continuing to consolidate our enterprise systems;

• 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.

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.

03/31/2018 Form 10-Q 2 WEC Energy Group, Inc.

PART I. FINANCIAL INFORMATION

ITEM 1. FINANCIAL STATEMENTS

WEC ENERGY GROUP, INC.

CONDENSED CONSOLIDATED INCOME STATEMENTS (Unaudited)	Three Months Ended
	March 31
(in millions, except per share amounts)	2018			2017
Operating revenues	$	2,286.5		$	2,304.5
Operating expenses
Cost of sales	972.1			941.1
Other operation and maintenance	511.9			504.5
Depreciation and amortization	208.6			194.6
Property and revenue taxes	48.8			49.6
Total operating expenses	1,741.4			1,689.8
Operating income	545.1			614.7
Equity in earnings of transmission affiliates	32.8			41.9
Other income, net	7.5			18.3
Interest expense	106.7			104.7
Other expense	(66.4		)	(44.5		)
Income before income taxes	478.7			570.2
Income tax expense	88.3			213.3
Net income	390.4			356.9
Preferred stock dividends of subsidiary	0.3			0.3
Net income attributed to common shareholders	$	390.1		$	356.6
Earnings per share
Basic	$	1.24		$	1.13
Diluted	$	1.23		$	1.12
Weighted average common shares outstanding
Basic	315.5			315.6
Diluted	316.9			317.2
Dividends per share of common stock	$	0.5525		$	0.5200

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

03/31/2018 Form 10-Q 3 WEC Energy Group, Inc.

WEC ENERGY GROUP, INC.

CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (Unaudited)	Three Months Ended
	March 31
(in millions)	2018			2017
Net income	$	390.4		$	356.9
Other comprehensive income (loss), net of tax
Derivatives accounted for as cash flow hedges
Reclassification of gains to net income, net of tax	(0.2		)	(0.3		)
Defined benefit plans
Amortization of pension and OPEB costs included in net periodic benefit cost, net of tax	1.9			0.1
Other comprehensive income (loss), net of tax	1.7			(0.2		)
Comprehensive income	392.1			356.7
Preferred stock dividends of subsidiary	0.3			0.3
Comprehensive income attributed to common shareholders	$	391.8		$	356.4

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

03/31/2018 Form 10-Q 4 WEC Energy Group, Inc.

WEC ENERGY GROUP, INC.

CONDENSED CONSOLIDATED BALANCE SHEETS (Unaudited) (in millions, except share and per share amounts)	March 31, 2018		December 31, 2017
Assets
Current assets
Cash and cash equivalents	$	48.1	$	38.9
Accounts receivable and unbilled revenues, net of reserves of $160.5 and $143.2, respectively	1,356.8		1,350.7
Materials, supplies, and inventories	376.0		539.0
Prepayments	165.9		210.0
Other	34.0		74.9
Current assets	1,980.8		2,213.5
Long-term assets
Property, plant, and equipment, net of accumulated depreciation of $8,819.8 and $8,618.5, respectively	21,466.3		21,347.0
Regulatory assets	2,929.7		2,803.2
Equity investment in transmission affiliates	1,598.9		1,553.4
Goodwill	3,052.8		3,053.5
Other	757.1		619.9
Long-term assets	29,804.8		29,377.0
Total assets	$	31,785.6	$	31,590.5
Liabilities and Equity
Current liabilities
Short-term debt	$	1,200.3	$	1,444.6
Current portion of long-term debt	957.9		842.1
Accounts payable	592.8		859.9
Accrued payroll and benefits	107.4		169.1
Other	747.5		553.6
Current liabilities	3,605.9		3,869.3
Long-term liabilities
Long-term debt	8,617.5		8,746.6
Deferred income taxes	3,069.9		2,999.8
Deferred revenue, net	538.1		543.3
Regulatory liabilities	3,924.3		3,718.6
Environmental remediation liabilities	617.2		617.4
Pension and OPEB obligations	523.1		397.4
Other	1,191.4		1,206.3
Long-term liabilities	18,481.5		18,229.4
Commitments and contingencies (Note 19)
Common shareholders' equity
Common stock – $0.01 par value; 325,000,000 shares authorized; 315,538,808 and 315,574,624 shares outstanding, respectively	3.2		3.2
Additional paid in capital	4,267.3		4,278.5
Retained earnings	5,392.7		5,176.8
Accumulated other comprehensive income	4.6		2.9
Common shareholders' equity	9,667.8		9,461.4
Preferred stock of subsidiary	30.4		30.4
Total liabilities and equity	$	31,785.6	$	31,590.5

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

03/31/2018 Form 10-Q 5 WEC Energy Group, Inc.

WEC ENERGY GROUP, INC.

CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS (Unaudited)	Three Months Ended
	March 31
(in millions)	2018			2017
Operating Activities
Net income	$	390.4		$	356.9
Reconciliation to cash provided by operating activities
Depreciation and amortization	208.6			194.6
Deferred income taxes and investment tax credits, net	17.0			150.2
Contributions and payments related to pension and OPEB plans	(5.3		)	(106.0		)
Equity income in transmission affiliates, net of distributions	7.1			(6.7		)
Change in –
Accounts receivable and unbilled revenues	(60.1		)	55.0
Materials, supplies, and inventories	163.0			170.5
Other current assets	81.3			41.2
Accounts payable	(170.9		)	(212.7		)
Other current liabilities	128.6			90.8
Other, net	134.3			(19.2		)
Net cash provided by operating activities	894.0			714.6
Investing Activities
Capital expenditures	(439.6		)	(329.7		)
Capital contributions to transmission affiliates	(12.8		)	(27.6		)
Proceeds from the sale of assets and businesses	0.8			13.1
Proceeds from the sale of investments held in rabbi trust	16.5			8.6
Other, net	(0.7		)	2.5
Net cash used in investing activities	(435.8		)	(333.1		)
Financing Activities
Exercise of stock options	2.1			5.9
Purchase of common stock	(15.8		)	(20.2		)
Dividends paid on common stock	(174.2		)	(164.1		)
Retirement of long-term debt	(12.6		)	(12.0		)
Change in short-term debt	(244.3		)	(189.8		)
Other, net	(0.3		)	(0.6		)
Net cash used in financing activities	(445.1		)	(380.8		)
Net change in cash, cash equivalents, and restricted cash	13.1			0.7
Cash, cash equivalents, and restricted cash at beginning of period	58.6			72.7
Cash, cash equivalents, and restricted cash at end of period	$	71.7		$	73.4

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

03/31/2018 Form 10-Q 6 WEC Energy Group, Inc.

WEC ENERGY GROUP, INC.

NOTES TO CONDENSED CONSOLIDATED FINANCIAL STATEMENTS (Unaudited)

March 31, 2018

NOTE 1—GENERAL INFORMATION

WEC Energy Group serves approximately 1.6 million electric customers and 2.9 million natural gas customers, and owns approximately 60% of ATC.

As used in these notes, the term "financial statements" refers to the condensed consolidated financial statements. This includes the income statements, statements of comprehensive income, balance sheets, and statements of cash flows, unless otherwise noted. In this report, when we refer to "the Company," "us," "we," "our," or "ours," we are referring to WEC Energy Group and all of its subsidiaries.

We have prepared the unaudited interim financial statements presented in this Form 10-Q pursuant to the rules and regulations of the SEC and GAAP. Accordingly, these financial statements do not include all of the information and footnotes required by GAAP for annual financial statements. These financial statements should be read in conjunction with the consolidated financial statements and footnotes in our Annual Report on Form 10-K for the year ended December 31, 2017. Financial results for an interim period may not give a true indication of results for the year. In particular, the results of operations for the three months ended March 31, 2018, are not necessarily indicative of expected results for 2018 due to seasonal variations and other factors.

In management's opinion, we have included all adjustments, normal and recurring in nature, necessary for a fair presentation of our financial results.

NOTE 2—ACQUISITIONS

Acquisition of a Wind Energy Generation Facility in Wisconsin

On April 2, 2018, WPS, along with two other unaffiliated utilities, completed the purchase of Forward Wind Energy Center, which consists of 86 wind turbines located in Wisconsin with a total capacity of 129 MW. The aggregate purchase price was $173.9 million of which WPS’s proportionate share was 44.6%, or $77.6 million. Since 2008 and up until the acquisition, WPS purchased 44.6% of the facility’s energy output under a power purchase agreement.

WPS's proportionate share of the facility will be recorded as property, plant, and equipment on the balance sheet and will be included in rate base. Under a joint ownership agreement with the two other utilities, WPS is entitled to its share of generating capability and output of the facility equal to its ownership interest. WPS will also pay its ownership share of additional construction costs and operating expenses.

Acquisition of Natural Gas Storage Facilities in Michigan

On June 30, 2017, we completed the acquisition of Bluewater for $226.0 million. Bluewater owns natural gas storage facilities in Michigan that will provide approximately one-third of the current storage needs for our Wisconsin natural gas utilities. In addition, we incurred $4.9 million of acquisition related costs.

The table below shows the allocation of the purchase price to the assets acquired and liabilities assumed at the date of the acquisition. The excess of the purchase price over the estimated fair values of the assets acquired and liabilities assumed was recognized as goodwill. Bluewater is included in the non-utility energy infrastructure segment. See Note 17, Segment Information, for more information.

(in millions)
Current assets	$	2.0
Net property, plant, and equipment	218.3
Goodwill	6.6
Current liabilities	(0.9		)
Total purchase price	$	226.0

03/31/2018 Form 10-Q 7 WEC Energy Group, Inc.

Acquisition of a Wind Energy Generation Facility in Nebraska

On April 30, 2018, we signed an agreement for the acquisition of an 80% membership interest in a 202.5 MW wind generating facility currently under construction known as Upstream Wind Energy Center (“Upstream”) for $276.0 million. Upstream is located in Antelope County, Nebraska and will supply energy to the Southwest Power Pool. The transaction is expected to close in the first quarter of 2019, after Upstream achieves commercial operation. Upstream has entered into an energy swap agreement pursuant to which Upstream will receive a fixed payment in exchange for substantially all of the energy output for a period of ten years. In addition, we anticipate Upstream will qualify for both Federal production tax credits at 100% of the published rate and bonus depreciation.

NOTE 3—DISPOSITION

Corporate and Other Segment—Sale of Bostco Real Estate Holdings

In March 2017, we sold the remaining real estate holdings of Bostco located in downtown Milwaukee, Wisconsin, which included retail, office, and residential space. During the first quarter of 2017, we recorded an insignificant gain on the sale, which was included in other income, net on our income statements. The assets included in the sale were not material and, therefore, were not presented as held for sale. The results of operations associated with these assets remained in continuing operations through the sale date as the sale did not represent a shift in our corporate strategy and did not have a major effect on our operations and financial results.

NOTE 4—OPERATING REVENUES

Adoption of ASU 2014-09, Revenues from Contracts with Customers

On January 1, 2018, we adopted ASU 2014-09, Revenues from Contracts with Customers, and the related amendments. In accordance with the guidance, revenues are recognized when control of the promised goods or services is transferred to our customers in an amount that reflects the consideration we expect to be entitled to receive in exchange for those goods or services.

We adopted this standard using the modified retrospective method. Results for reporting periods beginning after January 1, 2018, are presented under the new standard. The comparative information has not been restated and continues to be reported under the accounting standards in effect for those periods. Adoption of the standard did not result in an adjustment to our opening retained earnings balance as of January 1, 2018, and we do not expect the adoption of the standard to have a material impact on our net income in future periods.

We adopted the following practical expedients and optional exemptions for the implementation of this standard:

• We elected to exclude from the transaction price any amounts collected from customers for all sales taxes and other similar taxes.

• When applicable, we elected to apply the standard to a portfolio of contracts with similar characteristics, primarily our tariff-based contracts, as we reasonably expect that the effects on the financial statements of applying this guidance to the portfolio would not differ materially from applying this guidance to the individual contracts.

• We elected to recognize revenue in the amount we have the right to invoice for performance obligations satisfied over time when the consideration received from a customer corresponds directly with the value provided to the customer during the same period.

• We elected to not disclose the remaining performance obligations of a contract that has an original expected duration of one year or less.

• We elected to apply this standard only to contracts that are not completed as of the date of initial application.

03/31/2018 Form 10-Q 8 WEC Energy Group, Inc.

Disaggregation of Operating Revenues

The following tables present our operating revenues disaggregated by revenue source. Comparable amounts have not been presented for the three months ended March 31, 2017, due to our adoption of this standard under the modified retrospective method.

(in millions)	Wisconsin		Illinois			Other States			Total Utility Operations			Electric Transmission		Non-Utility Energy Infrastructure		Corporate and Other		Reconciling Eliminations			WEC Energy Group Consolidated
Three Months Ended March 31, 2018
Electric	$	1,067.7	$	—		$	—		$	1,067.7		$	—	$	—	$	—	$	—		$	1,067.7
Natural gas	518.0		507.6			172.7			1,198.3			—		14.9		—		(2.5		)	1,210.7
Total utility revenues	1,585.7		507.6			172.7			2,266.0			—		14.9		—		(2.5		)	2,278.4
Other non-utility revenues	—		—			3.9			3.9			—		7.1		1.3		(0.7		)	11.6
Total revenues from contracts with customers	1,585.7		507.6			176.6			2,269.9			—		22.0		1.3		(3.2		)	2,290.0
Other operating revenues	3.4		(0.3		)	(6.7		)	(3.6		)	—		96.1		0.1		(96.1		)	(3.5		)
Total operating revenues	$	1,589.1	$	507.3		$	169.9		$	2,266.3		$	—	$	118.1	$	1.4	$	(99.3	)	$	2,286.5

Revenues from Contracts with Customers

Electric Utility Operating Revenues

The following table disaggregates electric utility operating revenues into customer class for the current period:

(in millions)	Electric Utility Operating Revenues
Three Months Ended March 31, 2018
Residential	$	384.3
Small commercial and industrial	330.7
Large commercial and industrial	203.9
Other	7.7
Total retail revenues	926.6
Wholesale	54.9
Resale	73.8
Steam	9.7
Other utility revenues	2.7
Total electric utility operating revenues	$	1,067.7

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 Wisconsin residential and commercial and industrial customers and the majority of our Michigan residential and commercial and industrial customers, our performance obligation is bundled and consists of both the sale and the delivery of the electric commodity. In our Michigan service territory, a limited number of residential and commercial and industrial customers can purchase the commodity from a third party. In this case, the delivery of the electricity represents our sole performance obligation. The rates, charges, terms, and conditions of service for sales to these customers are included in tariffs that have been approved by state regulators. These rates often have a fixed component customer charge and a usage-based variable component. 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 using an output method based on the quantity of electricity delivered each month.

03/31/2018 Form 10-Q 9 WEC Energy Group, Inc.

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 our utilities provide generation to match the customer's load, similar to requirements contracts, or they can purchase specified quantities of electricity and capacity. The rates, charges, terms and conditions of service for sales to wholesale customers are included in tariffs that have been approved by the FERC. 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 utilities 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.

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. 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. 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.

Natural Gas Utility Operating Revenues

The following table disaggregates natural gas utility operating revenues into customer class for the current period:

(in millions)	Wisconsin			Illinois			Other States			Total Natural Gas Utility Operations
Three Months Ended March 31, 2018
Residential	$	356.7		$	332.6		$	123.2		$	812.5
Commercial and industrial	187.9			109.4			64.7			362.0
Total retail revenues	544.6			442.0			187.9			1,174.5
Transport	21.0			77.7			9.9			108.6
Other utility revenues *	(47.6		)	(12.1		)	(25.1		)	(84.8		)
Total natural gas utility operating revenues	$	518.0		$	507.6		$	172.7		$	1,198.3

* Includes amounts (refunded to) collected from customers for purchased gas adjustment costs.

We recognize natural gas utility operating revenues under requirements contracts with residential, commercial and industrial, and transportation customers served under the tariffs of our regulated utilities. 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 certain of our service territories, 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.

03/31/2018 Form 10-Q 10 WEC Energy Group, Inc.

The transaction price of the performance obligations is valued using rates in the tariffs of our regulated utilities, which have been approved by state regulators. These rates often have a fixed component customer charge and a usage-based variable component. 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 using an output method based on natural gas delivered each month.

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 Non-Utility Operating Revenues

Other non-utility operating revenues consist primarily of the following:

(in millions)	Three Months Ended March 31, 2018
We Power revenues	$	6.4
Appliance service revenues	3.9
Distributed renewable solar project revenues	1.3
Total other non-utility operating revenues	$	11.6

As part of the construction of the We Power electric generating units, we capitalized interest during construction, which is included in property, plant, and equipment. As allowed by the PSCW, we collected these carrying costs from WE's utility customers during construction. The equity portion of these carrying costs was recorded as deferred revenue, and we continually amortize the deferred carrying costs to revenues over the life of the plants to better match the costs of owning the plant while we are providing service to our customers. During the three months ended March 31, 2018, we recorded $6.4 million of revenue related to these deferred carrying costs, which were included in the contract liability balance at the beginning of the period. This contract liability is presented as deferred revenue, net on our balance sheets.

Non-utility operating revenues are derived primarily from servicing appliances for customers at MERC. These contracts customarily have a duration of one year or less and consist of a single performance obligation satisfied over time. We use a time-based output method to recognize revenues monthly for the service fee.

Revenues from distributed renewable solar projects consist primarily of sales of renewable energy and solar renewable energy certificates (SRECs) generated by WPS Power Development, LLC. The sale of SRECs is a distinct performance obligation as they are often sold separately from the renewable energy generated. Although the performance obligation for the sale of renewable energy is recognized over time and the performance obligation for SRECs is recognized at a point-in-time, the timing of revenue recognition is the same and occurs as renewable energy is generated.

Other Operating Revenues

Other operating revenues consist primarily of the following:

(in millions)	Three Months Ended March 31, 2018
Alternative revenues *	$	(16.1	)
Late payment charges	11.4
Leases	1.2
Total other operating revenues	$	(3.5	)

* Negative amounts can result from alternative revenues being reversed to revenues from contracts with customers as the customer is billed for these alternative revenues. Negative amounts can also result from revenues to be refunded to customers subject to decoupling mechanisms and wholesale true-ups, as discussed below.

03/31/2018 Form 10-Q 11 WEC Energy Group, Inc.

Alternative Revenues

Alternative revenues are created from programs authorized by regulators that allow our utilities 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. Alternative revenue programs allow compensation for the effects of weather abnormalities, other external factors, or demand side management initiatives. Alternative revenue programs can also provide incentive awards if the utility achieves certain objectives and in other limited circumstances. 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.

Below is a summary of the alternative revenue programs at our utilities:

• The rates of PGL, NSG, and MERC include decoupling mechanisms. These mechanisms differ by state and allow the utilities to recover or refund the differences between actual and authorized margins for certain customers.

• MERC’s rates include a conservation improvement program rider, which includes a financial incentive for meeting energy savings goals.

• WE and WPS provide wholesale electric service 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 or refund to the customer. We consider the true-up portion of the wholesale electric revenues to be alternative revenues.

NOTE 5—PROPERTY, PLANT, AND EQUIPMENT

Wisconsin Segment Plant to be Retired

We have evaluated future plans for our older and less efficient fossil fuel generating units and have announced the retirement of the plants identified below. The net book value of these plants was classified as plant to be retired within property, plant, and equipment on our balance sheet at March 31, 2018. In addition, severance expense in the amount of $29.4 million was recorded within the Wisconsin segment in 2017 related to these announced plant retirements.

Pleasant Prairie Power Plant

As a result of a MISO ruling in December 2017, the Pleasant Prairie power plant was retired effective April 10, 2018. Retirement of the Pleasant Prairie power plant was considered probable at March 31, 2018. The net book value of this generating unit was $674.1 million at March 31, 2018, and was classified as plant to be retired within property, plant, and equipment on our balance sheet. This unit is included in rate base, and WE continues to depreciate it on a straight-line basis using the composite depreciation rates approved by the PSCW. The physical dismantlement of the plant will not occur immediately. It may take several years to finalize long-term plans for the site. See Note 19, Commitments and Contingencies, for more information.

Presque Isle Power Plant

In October 2017, the MPSC approved UMERC’s application to construct and operate approximately 180 MW of natural gas-fired generation in the Upper Peninsula of Michigan. The new units are expected to begin commercial operation by mid-2019. Upon receiving the MPSC's approval, retirement of the PIPP generating units became probable. As a result of a MISO ruling received in April 2018, the PIPP units must be retired no later than May 31, 2019. The net book value of these units was $188.7 million at March 31, 2018, and 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 continues to depreciate them on a straight-line basis using the composite depreciation rates approved by the PSCW. See Note 19, Commitments and Contingencies, and Note 21, Regulatory Environment, for more information.

Pulliam Power Plant

WPS anticipates retiring Pulliam generating units 7 and 8 near the end of 2018 when certain transmission lines are completed. Retirement of the Pulliam generating units was probable at March 31, 2018. The net book value of these generating units was $43.6 million at March 31, 2018, and was classified as plant to be retired within property, plant, and equipment on our balance

03/31/2018 Form 10-Q 12 WEC Energy Group, Inc.

sheet. These units are included in rate base, and WPS continues to depreciate them on a straight-line basis using the composite depreciation rates approved by the PSCW. See Note 19, Commitments and Contingencies, for more information.

Edgewater Unit 4

As a result of the continued implementation of the Consent Decree related to the jointly owned Columbia and Edgewater plants, retirement of the Edgewater 4 generating unit was probable at March 31, 2018. The plant must be retired by September 30, 2018. The net book value of WPS's ownership share of this generating unit was $12.7 million at March 31, 2018, and was classified as plant to be retired within property, plant, and equipment on our balance sheet. This unit is included in rate base, and WPS continues to depreciate it on a straight-line basis using the composite depreciation rates approved by the PSCW. See Note 19, Commitments and Contingencies, for more information regarding the Consent Decree.

NOTE 6—COMMON EQUITY

Stock-Based Compensation

During the first quarter of 2018, the Compensation Committee of our Board of Directors awarded the following stock-based compensation awards to our directors, officers, and certain other key employees:

Award Type	Number of Awards
Stock options (1)	710,710
Restricted shares (2)	156,340
Performance units	217,560

⁽¹⁾  Stock options awarded had a weighted-average exercise price of $65.60 and a weighted-average grant date fair value of $7.71 per option.

⁽²⁾  Restricted shares awarded had a weighted-average grant date fair value of $64.20 per share.

Restrictions

Our ability as a holding company to pay common stock dividends primarily depends on the availability of funds received from our utility subsidiaries and our non-utility subsidiary, We Power. Various financing arrangements and regulatory requirements impose certain restrictions on the ability of our subsidiaries to transfer funds to us in the form of cash dividends, loans, or advances. All of our utility subsidiaries, with the exception of UMERC and MGU, are prohibited from loaning funds to us, either directly or indirectly.

See Note 9, Common Equity, in our 2017 Annual Report on Form 10-K for additional information on these and other restrictions.

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

Common Stock Dividends

On April 19, 2018, our Board of Directors declared a quarterly cash dividend of $0.5525 per share, payable on June 1, 2018, to shareholders of record on May 14, 2018.

NOTE 7—SHORT-TERM DEBT AND LINES OF CREDIT

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

(in millions, except percentages)	March 31, 2018			December 31, 2017
Commercial paper
Amount outstanding	$	1,200.3		$	1,444.6
Weighted-average interest rate on amounts outstanding	2.24		%	1.77		%

Our average amount of commercial paper borrowings based on daily outstanding balances during the three months ended March 31, 2018, was $1,254.4 million with a weighted-average interest rate during the period of 1.90%.

03/31/2018 Form 10-Q 13 WEC Energy Group, Inc.

The information in the table below relates to our revolving credit facilities used to support our commercial paper borrowing programs, including available capacity under these facilities:

(in millions)	Maturity	March 31, 2018
WEC Energy Group	October 2022	$	1,200.0
WE	October 2022	500.0
WPS	October 2022	400.0
WG	October 2022	350.0
PGL	October 2022	350.0
Total short-term credit capacity		$	2,800.0
Less:
Letters of credit issued inside credit facilities		$	1.2
Commercial paper outstanding		1,200.3
Available capacity under existing agreements		$	1,598.5

NOTE 8—LONG-TERM DEBT

Integrys Holding, Inc.

In April 2018, Integrys issued a notice to redeem at par all $114.9 million outstanding of its 2006 Junior Subordinated Notes due December 1, 2066. The redemption will be effective May 14, 2018. As a result, the $114.9 million outstanding balance was included in the current portion of long-term debt on our balance sheet at March 31, 2018.

NOTE 9—MATERIALS, SUPPLIES, AND INVENTORIES

Our inventory consisted of:

(in millions)	March 31, 2018		December 31, 2017
Natural gas in storage	$	34.8	$	209.0
Materials and supplies	213.7		211.2
Fossil fuel	127.5		118.8
Total	$	376.0	$	539.0

PGL and NSG price natural gas storage injections at the calendar year average of the costs of natural gas supply purchased. Withdrawals from storage are priced on the LIFO cost method. For interim periods, the difference between current projected replacement cost and the LIFO cost for quantities of natural gas temporarily withdrawn from storage is recorded as a temporary LIFO liquidation debit or credit. At March 31, 2018, we had a temporary LIFO liquidation credit of $35.6 million recorded within other current liabilities on our balance sheet. Due to seasonality requirements, PGL and NSG expect these interim reductions in LIFO layers to be replenished by year end.

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

NOTE 10—INCOME TAXES

The provision for income taxes for the quarter ended March 31, 2018, 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:

	Amount			Effective Tax Rate
Statutory federal income tax	$	100.5		21.0	%
State income taxes net of federal tax benefit	29.9			6.2	%
Federal tax reform	(15.5		)	(3.2	)%
Tax repairs	(25.5		)	(5.3	)%
Other	(1.1		)	(0.3	)%
Total income tax expense	$	88.3		18.4	%

03/31/2018 Form 10-Q 14 WEC Energy Group, Inc.

The effective tax rate of 18.4% for the first quarter of 2018 differs from the United States statutory federal income tax rate of 21% primarily due to the impact of the Tax Legislation and the flow through of tax repairs in connection with the Wisconsin rate settlement, partially offset by state income taxes. The Tax Legislation, signed into law in December 2017, required our regulated utilities to remeasure their deferred income taxes and begin to amortize the resulting excess deferred income taxes beginning in 2018 in accordance with normalization requirements (see Federal tax reform line above). See Note 21, Regulatory Environment, for more information about the impact of the Tax Legislation and the Wisconsin rate settlement.

On December 22, 2017, the SEC staff issued guidance in Staff Accounting Bulletin 118 (SAB 118), Income Tax Accounting Implications of the Tax Cuts and Jobs Act, which provides for a measurement period of up to one year from the enactment date to complete accounting under GAAP for the tax effects of the legislation. Due to the complex and comprehensive nature of the enacted tax law changes, and their application under GAAP, certain amounts related to bonus depreciation and future tax benefit utilization recorded in the financial statements as a result of the Tax Legislation are to be considered "provisional" as discussed in SAB 118 and subject to revision. We are awaiting additional guidance from industry and income tax authorities in order to finalize our accounting.

NOTE 11—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 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 financial 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 are categorized in Level 3 due to the significance of unobservable or internally-developed inputs.

We recognize transfers between levels of the fair value hierarchy at their value as of the end of the reporting period.

03/31/2018 Form 10-Q 15 WEC Energy Group, Inc.

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:

	March 31, 2018
(in millions)	Level 1		Level 2		Level 3		Total
Derivative assets
Natural gas contracts	$	1.7	$	0.5	$	—	$	2.2
Petroleum products contracts	0.6		—		—		0.6
FTRs	—		—		1.5		1.5
Coal contracts	—		1.1		—		1.1
Total derivative assets	$	2.3	$	1.6	$	1.5	$	5.4
Investments held in rabbi trust	$	103.6	$	—	$	—	$	103.6
Derivative liabilities
Natural gas contracts	$	3.4	$	1.4	$	—	$	4.8
Coal contracts	—		0.3		—		0.3
Total derivative liabilities	$	3.4	$	1.7	$	—	$	5.1

	December 31, 2017
(in millions)	Level 1		Level 2		Level 3		Total
Derivative assets
Natural gas contracts	$	1.8	$	3.9	$	—	$	5.7
Petroleum products contracts	1.2		—		—		1.2
FTRs	—		—		4.4		4.4
Coal contracts	—		1.1		—		1.1
Total derivative assets	$	3.0	$	5.0	$	4.4	$	12.4
Investments held in rabbi trust	$	120.7	$	—	$	—	$	120.7
Derivative liabilities
Natural gas contracts	$	7.0	$	3.8	$	—	$	10.8
Coal contracts	—		0.8		—		0.8
Total derivative liabilities	$	7.0	$	4.6	$	—	$	11.6

The derivative assets and liabilities listed in the tables above include options, swaps, 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.

We hold investments in the Integrys rabbi trust. These investments are restricted as they can only be withdrawn from the trust to fund participants' benefits under the Integrys deferred compensation plan and certain Integrys non-qualified pension plans. As we do not intend to sell the investments in the near term, they are included in other long-term assets on our balance sheets. For the three months ended March 31, 2018 and 2017, the net unrealized (losses) and gains included in earnings related to the investments held at the end of the period were $(3.1) million and $5.2 million, respectively.

The following table summarizes the changes to derivatives classified as Level 3 in the fair value hierarchy:

	Three Months Ended March 31
(in millions)	2018			2017
Balance at the beginning of the period	$	4.4		$	5.1
Settlements	(2.9		)	(3.4		)
Balance at the end of the period	$	1.5		$	1.7

03/31/2018 Form 10-Q 16 WEC Energy Group, Inc.

Fair Value of Financial Instruments

The following table shows the financial instruments included on our balance sheets that are not recorded at fair value:

	March 31, 2018				December 31, 2017
(in millions)	Carrying Amount		Fair Value		Carrying Amount		Fair Value
Preferred stock	$	30.4	$	29.1	$	30.4	$	30.5
Long-term debt, including current portion *	9,549.3		10,054.5		9,561.7		10,341.9

* The carrying amount of long-term debt excludes capital lease obligations of $26.1 million and $27.0 million at March 31, 2018 and December 31, 2017, respectively.

The fair values of our long-term debt and preferred stock are categorized within Level 2 of the fair value hierarchy.

NOTE 12—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 and shareholders. Our approach is non-speculative and designed to mitigate risk. Regulated hedging programs are approved by our state regulators.

We record derivative instruments on our balance sheets as an asset or liability 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, our regulators allow the effects of fair value accounting to be offset to regulatory assets and liabilities.

The following table shows our derivative assets and derivative liabilities:

	March 31, 2018				December 31, 2017
(in millions)	Derivative Assets		Derivative Liabilities		Derivative Assets		Derivative Liabilities
Other current
Natural gas contracts	$	2.2	$	3.7	$	5.6	$	9.4
Petroleum products contracts	0.6		—		1.2		—
FTRs	1.5		—		4.4		—
Coal contracts	0.8		0.3		0.6		0.6
Total other current *	$	5.1	$	4.0	$	11.8	$	10.0
Other long-term
Natural gas contracts	$	—	$	1.1	$	0.1	$	1.4
Coal contracts	0.3		—		0.5		0.2
Total other long-term *	$	0.3	$	1.1	$	0.6	$	1.6
Total	$	5.4	$	5.1	$	12.4	$	11.6

* On our balance sheets, we classify derivative assets and liabilities as other current or other long-term based on the maturities of the underlying contracts.

Realized gains (losses) on derivative instruments are primarily recorded in cost of sales on the income statements. Our estimated notional sales volumes and realized gains (losses) were as follows:

	Three Months Ended March 31, 2018				Three Months Ended March 31, 2017
(in millions)	Volumes	Gains (Losses)			Volumes	Gains (Losses)
Natural gas contracts	48.1 Dth	$	(5.2	)	34.1 Dth	$	(0.3	)
Petroleum products contracts	2.1 gallons	0.5			4.9 gallons	(0.5		)
FTRs	8.2 MWh	3.7			9.2 MWh	3.0
Total		$	(1.0	)		$	2.2

03/31/2018 Form 10-Q 17 WEC Energy Group, Inc.

On our balance sheets, the amounts recognized for the right to reclaim cash collateral or the obligation to return cash collateral are not offset against the fair value amounts recognized for derivative instruments executed with the same counterparty under the same master netting arrangement. At March 31, 2018 and December 31, 2017, we had posted cash collateral of $11.8 million and $16.2 million, respectively, in our margin accounts. These amounts were recorded on our balance sheets in other current assets.

The following table shows derivative assets and derivative liabilities if derivative instruments by counterparty were presented net on our balance sheets:

	March 31, 2018							December 31, 2017
(in millions)	Derivative Assets			Derivative Liabilities				Derivative Assets			Derivative Liabilities
Gross amount recognized on the balance sheet	$	5.4		$	5.1			$	12.4		$	11.6
Gross amount not offset on the balance sheet	(2.1		)	(3.7		)	(1)	(4.9		)	(9.0		)	(2)
Net amount	$	3.3		$	1.4			$	7.5		$	2.6

⁽¹⁾   Includes cash collateral posted of $1.6 million.

⁽²⁾  Includes cash collateral posted of $4.1 million.

Certain of our derivative and nonderivative commodity instruments contain provisions that could require "adequate assurance" in the event of a material change in our creditworthiness, or the posting of additional collateral for instruments in net liability positions, if triggered by a decrease in credit ratings. The aggregate fair value of all derivative instruments with specific credit risk-related contingent features that were in a net liability position was $1.1 million and $3.7 million at March 31, 2018 and December 31, 2017, respectively. At March 31, 2018 and December 31, 2017, we had not posted any collateral related to the credit risk-related contingent features of these commodity instruments. If all of the credit risk-related contingent features contained in derivative instruments in a net liability position had been triggered at March 31, 2018 and December 31, 2017, we would have been required to post collateral of $1.5 million and $2.7 million, respectively.

NOTE 13—GUARANTEES

The following table shows our outstanding guarantees:

			Expiration
(in millions)	Total Amounts Committed at March 31, 2018		Less Than 1 Year		1 to 3 Years		Over 3 Years
Guarantees
Guarantees supporting commodity transactions of subsidiaries (1)	$	8.1	$	8.1	$	—	$	—
Standby letters of credit (2)	71.4		46.0		25.4		—
Surety bonds (3)	9.8		9.7		0.1		—
Other guarantees (4)	11.1		0.5		—		10.6
Total guarantees	$	100.4	$	64.3	$	25.5	$	10.6

⁽¹⁾  Consists of $8.1 million to support the business operations of Bluewater.

⁽²⁾  At our request or the request of our subsidiaries, financial institutions have issued standby letters of credit for the benefit of third parties that have extended credit to our subsidiaries. These amounts are not reflected on our balance sheets.

⁽³⁾  Primarily for workers compensation self-insurance programs and obtaining various licenses, permits, and rights-of-way. These amounts are not reflected on our balance sheets.

⁽⁴⁾  Consists of $11.1 million related to other indemnifications, for which a liability of $10.6 million related to workers compensation coverage was recorded on our balance sheets.

03/31/2018 Form 10-Q 18 WEC Energy Group, Inc.

NOTE 14—EMPLOYEE BENEFITS

The following tables show the components of net periodic pension and OPEB costs for our benefit plans.

	Pension Costs
	Three Months Ended March 31
(in millions)	2018			2017
Service cost	$	12.0		$	11.7
Interest cost	28.3			31.2
Expected return on plan assets	(49.6		)	(49.6		)
Loss on plan settlement	0.4			—
Amortization of prior service cost	0.7			0.7
Amortization of net actuarial loss	23.1			21.9
Net periodic benefit cost	$	14.9		$	15.9

	OPEB Costs
	Three Months Ended March 31
(in millions)	2018			2017
Service cost	$	6.2		$	6.3
Interest cost	7.5			8.5
Expected return on plan assets	(14.9		)	(13.7		)
Amortization of prior service credit	(3.8		)	(2.8		)
Amortization of net actuarial loss	0.3			1.5
Net periodic benefit credit	$	(4.7	)	$	(0.2	)

During the three months ended March 31, 2018, we made contributions and payments of $3.7 million related to our pension plans and $1.6 million related to our OPEB plans. We expect to make contributions and payments of $8.5 million related to our pension plans and $7.9 million related to our OPEB plans during the remainder of 2018, dependent upon various factors affecting us, including our liquidity position and the effects of the new Tax Legislation.

Effective January 1, 2018, we adopted ASU 2017-07, Improving the Presentation of Net Periodic Pension Cost and Net Periodic Postretirement Benefit Cost, which modifies certain aspects of the accounting for employee benefit costs. Under the new guidance, only the service cost component can be included in total operating expenses. The remaining components of net periodic benefit cost are required to be presented in the income statement separately from the service cost component, outside of operating income. As required, this change was applied retrospectively to all prior periods presented. Accordingly, for the quarters ended March 31, 2018 and 2017, we have presented the service cost component of our retirement benefit plans in other operation and maintenance on the income statements, while presenting the non-service cost components in other income, net. For the quarters ended March 31, 2018 and 2017, the non-service cost components of net benefit cost were in a net credit position, in the amount of $(7.2) million and $(2.6) million, respectively. The $(2.6) million related to the first quarter of 2017 was reclassified from other operation and maintenance to other income, net on our income statements.

As required by ASU 2017-07, our income statements for the years ended December 31, 2017, 2016, and 2015 were retroactively restated from what was previously presented in our 2017 Annual Report on Form 10-K. The impacts to our income statements from adoption of this standard are reflected in the table below.

	Year Ended December 31, 2017						Year Ended December 31, 2016							Year Ended December 31, 2015
(in millions)	Form 10-K Income Statement		Impact of ASU 2017-07		Income Statement After Adoption		Form 10-K Income Statement		Impact of ASU 2017-07			Income Statement After Adoption		Form 10-K Income Statement		Impact of ASU 2017-07		Income Statement After Adoption
Operating expenses
Other operation and maintenance	$	2,047.0	$	9.1	$	2,056.1	$	2,185.5	$	(14.2	)	$	2,171.3	$	1,709.3	$	1.4	$	1,710.7
Other expense
Other income, net	64.6		9.1		73.7		80.8		(14.2		)	66.6		58.9		1.4		60.3

03/31/2018 Form 10-Q 19 WEC Energy Group, Inc.

In addition, under ASU 2017-07, only the service cost component of net periodic benefit cost is eligible for capitalization to property, plant, and equipment. In prior periods, a portion of all net benefit cost components was capitalized to property, plant, and equipment. As required, this amendment was applied prospectively, beginning January 1, 2018. As a result of the application of accounting principles for rate regulated entities, the non-service cost components of the net benefit cost that are no longer eligible for capitalization under this standard, but are capitalized under the regulatory framework, will be presented as regulatory assets or liabilities rather than property, plant, and equipment.

NOTE 15—GOODWILL

Goodwill represents the excess of the cost of an acquisition over the fair value of the identifiable net assets acquired. The following table shows changes to our goodwill balances by segment during the three months ended March 31, 2018:

(in millions)	Wisconsin		Illinois		Other States		Non-Utility Energy Infrastructure			Total
Goodwill balance as of January 1, 2018	$	2,104.3	$	758.7	$	183.2	$	7.3		$	3,053.5
Adjustment to Bluewater purchase price allocation (1)	—		—		—		(0.7		)	(0.7		)
Goodwill balance as of March 31, 2018 (2)	$	2,104.3	$	758.7	$	183.2	$	6.6		$	3,052.8

⁽¹⁾  See Note 2, Acquisitions, for more information on the acquisition of Bluewater.

⁽²⁾  We had no accumulated impairment losses related to our goodwill as of March 31, 2018.

NOTE 16—INVESTMENT IN TRANSMISSION AFFILIATES

We own approximately 60% of ATC, a for-profit, transmission-only company regulated by the FERC for cost of service and certain state regulatory commissions for routing and siting of transmission projects. We also own approximately 75% of ATC Holdco, a separate entity formed in December 2016 to invest in transmission-related projects outside of ATC's traditional footprint. The following tables provide a reconciliation of the changes in our investments in ATC and ATC Holdco:

	Three Months Ended March 31, 2018
(in millions)	ATC		ATC Holdco			Total
Balance at beginning of period *	$	1,515.8	$	37.6		$	1,553.4
Add: Earnings (loss) from equity method investment	33.4		(0.6		)	32.8
Add: Capital contributions	12.0		0.8			12.8
Less: Other	0.1		—			0.1
Balance at end of period	$	1,561.1	$	37.8		$	1,598.9

* Distributions of $39.9 million, received in the first quarter of 2018, were approved and recorded as a receivable from ATC in other current assets at December 31, 2017.

	Three Months Ended March 31, 2017
(in millions)	ATC		ATC Holdco			Total
Balance at beginning of period *	$	1,443.9	$	—		$	1,443.9
Add: Earnings (loss) from equity method investment	47.7		(5.8		)	41.9
Add: Capital contributions	24.1		3.5			27.6
Less: Other	0.1		—			0.1
Balance at end of period	$	1,515.6	$	(2.3	)	$	1,513.3

* Distributions of $35.2 million, received in the first quarter of 2017, were approved and recorded as a receivable from ATC in other current assets at December 31, 2016.

We pay ATC for network 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. We are required to pay the cost of needed transmission infrastructure upgrades for new generation projects while the projects are under construction. ATC reimburses us for these costs when the new generation is placed in service.

03/31/2018 Form 10-Q 20 WEC Energy Group, Inc.

The following table summarizes our significant related party transactions with ATC:

	Three Months Ended March 31
(in millions)	2018		2017
Charges to ATC for services and construction	$	4.6	$	4.2
Charges from ATC for network transmission services	84.5		87.3
Refund from ATC per FERC ROE order	—		28.3

Our balance sheets included the following receivables and payables related to ATC:

(in millions)	March 31, 2018		December 31, 2017
Accounts receivable
Services provided to ATC	$	1.8	$	1.5
Other current assets
Dividends receivable from ATC	—		39.9
Accounts payable
Services received from ATC	24.0		31.2

Summarized financial data for ATC is included in the following tables:

	Three Months Ended March 31
(in millions)	2018		2017
Income statement data
Operating revenues	$	165.4	$	174.7
Operating expenses	84.9		82.7
Other expense, net	27.6		26.1
Net income	$	52.9	$	65.9

(in millions)	March 31, 2018		December 31, 2017
Balance sheet data
Current assets	$	84.7	$	87.7
Noncurrent assets	4,681.7		4,598.9
Total assets	$	4,766.4	$	4,686.6
Current liabilities	$	473.3	$	767.2
Long-term debt	2,065.3		1,790.6
Other noncurrent liabilities	266.4		240.3
Shareholders' equity	1,961.4		1,888.5
Total liabilities and shareholders' equity	$	4,766.4	$	4,686.6

NOTE 17—SEGMENT INFORMATION

At March 31, 2018, we reported six segments, which are described below.

• The Wisconsin segment includes the electric and natural gas utility operations of WE, WG, WPS, and UMERC.

• The Illinois segment includes the natural gas utility and non-utility operations of PGL and NSG.

• The other states segment includes the natural gas utility and non-utility operations of MERC and MGU.

• The electric transmission segment includes our approximate 60% ownership interest in ATC, a for-profit, transmission-only company regulated by the FERC for cost of service and certain state regulatory commissions for routing and siting of transmission projects, and our approximate 75% ownership interest in ATC Holdco, which invests in transmission-related projects outside of ATC's traditional footprint.

03/31/2018 Form 10-Q 21 WEC Energy Group, Inc.

• The non-utility energy infrastructure segment includes We Power, which owns and leases generating facilities to WE, and Bluewater, which owns underground natural gas storage facilities in Michigan.

• The corporate and other segment includes the operations of the WEC Energy Group holding company, the Integrys holding company, the Peoples Energy, LLC holding company, Wispark LLC, Bostco, Wisvest LLC, Wisconsin Energy Capital Corporation, WBS, and WPS Power Development LLC. In the first quarter of 2017, we sold substantially all of the remaining assets of Bostco. See Note 3, Disposition, for more information on this sale.

All of our operations are located within the United States. The following tables show summarized financial information related to our reportable segments for the three months ended March 31, 2018 and 2017:

	Utility Operations
(in millions)	Wisconsin		Illinois		Other States		Total Utility Operations		Electric Transmission		Non-Utility Energy Infrastructure		Corporate and Other			Reconciling Eliminations			WEC Energy Group Consolidated
Three Months Ended
March 31, 2018
External revenues	$	1,589.1	$	507.3	$	169.9	$	2,266.3	$	—	$	18.8	$	1.4		$	—		$	2,286.5
Intersegment revenues	—		—		—		—		—		99.3		—			(99.3		)	—
Other operation and maintenance	468.5		112.2		26.6		607.3		—		1.7		(0.3		)	(96.8		)	511.9
Depreciation and amortization	135.1		40.9		6.6		182.6		—		18.3		7.7			—			208.6
Operating income (loss)	273.7		147.6		36.2		457.5		—		93.0		(5.4		)	—			545.1
Equity in earnings of transmission affiliates	—		—		—		—		32.8		—		—			—			32.8
Interest expense	49.4		12.3		2.1		63.8		—		16.1		28.0			(1.2		)	106.7

	Utility Operations
(in millions)	Wisconsin		Illinois		Other States		Total Utility Operations		Electric Transmission		Non-Utility Energy Infrastructure		Corporate and Other			Reconciling Eliminations			WEC Energy Group Consolidated
Three Months Ended
March 31, 2017
External revenues	$	1,612.1	$	525.3	$	157.9	$	2,295.3	$	—	$	6.3	$	2.9		$	—		$	2,304.5
Intersegment revenues	—		—		—		—		—		109.0		—			(109.0		)	—
Other operation and maintenance *	465.7		119.6		28.2		613.5		—		0.4		(0.4		)	(109.0		)	504.5
Depreciation and amortization	129.3		36.2		6.0		171.5		—		17.5		5.6			—			194.6
Operating income (loss) *	329.5		156.7		33.5		519.7		—		97.4		(2.4		)	—			614.7
Equity in earnings of transmission affiliates	—		—		—		—		41.9		—		—			—			41.9
Interest expense	48.7		11.1		2.3		62.1		—		15.3		29.1			(1.8		)	104.7

* Includes the retroactive restatement impacts of the implementation of ASU 2017-07. See Note 14, Employee Benefits, for more information on this new standard.

NOTE 18—VARIABLE INTEREST ENTITIES

The primary beneficiary of a variable interest entity must consolidate the entity's assets and liabilities. In addition, certain disclosures are required for significant interest holders in variable interest entities.

03/31/2018 Form 10-Q 22 WEC Energy Group, Inc.

We assess our relationships with potential variable interest entities, such as our coal suppliers, natural gas suppliers, coal transporters, natural gas transporters, and other counterparties related to power purchase agreements, 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.

Investment in Transmission Affiliates

We own approximately 60% of ATC, a for-profit, electric transmission company regulated by the FERC and certain state regulatory commissions. We have determined that ATC is a variable interest entity but that consolidation is not required since we are not ATC's primary beneficiary. As a result of our limited voting rights, we do not have the power to direct the activities that most significantly impact ATC's economic performance. We account for ATC as an equity method investment. The significant assets and liabilities related to ATC recorded on our balance sheets were our equity investment, distributions receivable, and accounts payable. At March 31, 2018 and December 31, 2017, our equity investment was $1,561.1 million and $1,515.8 million, respectively, which approximates our maximum exposure to loss as a result of our involvement with ATC. In addition, we had a receivable of $39.9 million recorded at December 31, 2017 for distributions from ATC. We also had $24.0 million and $31.2 million of accounts payable due to ATC at March 31, 2018 and December 31, 2017, respectively, for network transmission services.

We also own approximately 75% of ATC Holdco, a separate entity formed in December 2016 to invest in transmission-related projects outside of ATC's traditional footprint. We have determined that ATC Holdco is a variable interest entity but that consolidation is not required since we are not ATC Holdco's primary beneficiary. As a result of our limited voting rights, we do not have the power to direct the activities that most significantly impact ATC Holdco's economic performance. We account for ATC Holdco as an equity method investment. The only significant asset or liability related to ATC Holdco recorded on our balance sheets was our equity investment of $37.8 million and $37.6 million at March 31, 2018 and December 31, 2017, respectively. Our equity investment approximates our maximum exposure to loss as a result of our involvement with ATC Holdco.

See Note 16, Investment in Transmission Affiliates, for more information.

Purchased Power Agreement

We have a purchased power agreement that represents a variable interest. This agreement is for 236 MW of firm capacity from a natural gas-fired cogeneration facility, and we account for it as a capital lease. The agreement includes no minimum energy requirements over the remaining term of approximately four years. We have examined the risks of the entity, including operations, maintenance, dispatch, financing, fuel costs, and other factors, and have determined that we are not the primary beneficiary of the entity. We do not hold an equity or debt interest in the entity, and there is no residual guarantee associated with the purchased power agreement.

We have approximately $67.7 million of required payments over the remaining term of this agreement. We believe that the required lease payments under this contract will continue to be recoverable in rates. Total capacity and lease payments under this contract for the three months ended March 31, 2018 and 2017 were $4.7 million and $4.5 million, respectively. Our maximum exposure to loss is limited to the capacity payments under the contract.

NOTE 19—COMMITMENTS AND CONTINGENCIES

We and our subsidiaries 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

Our electric utilities have obligations to distribute and sell electricity to their customers, and our natural gas utilities have obligations to distribute and sell natural gas to their customers. The utilities 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. Our minimum future commitments related to these purchase obligations as of March 31, 2018, including those of our subsidiaries, were $11,473.4 million. This amount excludes WPS's purchase obligations under a power purchase agreement with Forward Wind Energy Center, as the agreement was terminated on April 2, 2018, in connection with the acquisition of the facility. See Note 2, Acquisitions, for more information.

03/31/2018 Form 10-Q 23 WEC Energy Group, Inc.

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 sulfur dioxide, nitrogen oxide, fine particulates, mercury, and GHGs; water intake and discharges; disposal of coal combustion products such as fly ash; and remediation of impacted properties, including former manufactured gas plant sites.

Air Quality

8-Hour Ozone National Ambient Air Quality Standards

After completing its review of the 2008 ozone standard, the EPA released a final rule in October 2015, which lowered the limit for ground-level ozone, creating a more stringent standard than the 2008 NAAQS. In December 2017, the EPA informed Wisconsin of its intended area designations of all the counties along Wisconsin's Lake Michigan shoreline, except Brown, Kewaunee, Marinette, and Oconto Counties, as either partial or full nonattainment. Waukesha and Washington counties were also included due to the counties being in the Milwaukee combined statistical area. The EPA issued final nonattainment area designations on May 1, 2018. The final designations differ significantly from the intended nonattainment areas EPA proposed late in December 2017. The following counties were designated as partial nonattainment: Manitowoc, Sheboygan, Northern Milwaukee/Ozaukee shoreline, and Kenosha. Racine, Waukesha, and Washington counties will be designated attainment/unclassifiable. For nonattainment areas, the state of Wisconsin will have to develop a state implementation plan to bring the areas back into attainment. We will be required to comply with this state implementation plan no earlier than 2020. We believe we are well positioned to meet the requirements associated with the ozone standard and do not expect to incur significant costs to comply.

Climate Change

In 2015, the EPA issued a final rule regulating GHG emissions from existing generating units, referred to as the Clean Power Plan, a proposed federal plan and model trading rules as alternatives or guides to state compliance plans, and final performance standards for modified and reconstructed generating units and new fossil-fueled power plants. In October 2015, following publication of the CPP, numerous states (including Wisconsin and Michigan) and other parties filed lawsuits challenging the final rule, including a request to stay the implementation of the final rule pending the outcome of these legal challenges. The D.C. Circuit Court of Appeals denied the stay request, but in February 2016, the Supreme Court stayed the effectiveness of the CPP until disposition of the litigation in the D.C. Circuit Court of Appeals and, to the extent that further appellate review is sought, at the Supreme Court. The D.C. Circuit Court of Appeals heard one case in September 2016, and the other case is still pending. In April 2017, pursuant to motions made by the EPA, the D.C. Circuit Court of Appeals ordered the cases to be held in abeyance. Supplemental briefs were provided addressing whether the cases should be remanded to the EPA rather than held in abeyance. The EPA argued that the cases should continue to be held in abeyance pending the conclusion of the EPA's review of the CPP and any resulting rulemaking.

The CPP seeks to achieve state-specific GHG emission reduction goals by 2030, and would have required states to submit plans by September 2016. The goal of the final rule is to reduce nationwide GHG emissions by 32% from 2005 levels. The rule is seeking GHG emission reductions in Wisconsin and Michigan of 41% and 39%, respectively, below 2012 levels by 2030. Interim goals starting in 2022 would require states to achieve about two-thirds of the 2030 required reduction.

In March 2017, President Trump issued an executive order that, among other things, specifically directs the EPA to review, and if appropriate, initiate proceedings to suspend, revise, or rescind the CPP and related GHG regulations for new, reconstructed, or modified fossil-fueled power plants. As a result of this order and related EPA review, as well as the ongoing legal proceedings, the timelines for the GHG emission reduction goals and all other aspects of the CPP are uncertain. In April 2017, the EPA withdrew the proposed rule for a federal plan and model trading rules that were published in October 2015 for use in developing state plans to implement the CPP or for use in states where a plan is not submitted or approved. In October 2017, the EPA issued a proposed rulemaking to repeal the CPP. In December 2017 the EPA issued an advanced notice of proposed rulemaking to solicit input on whether it is appropriate to replace the CPP. In addition, the Governor of Wisconsin issued an executive order in February 2016, which prohibits state agencies, departments, boards, commissions, or other state entities from developing or promoting the development of a state plan to implement the CPP.

03/31/2018 Form 10-Q 24 WEC Energy Group, Inc.

Notwithstanding the uncertain future of the CPP, and given current fuel and technology markets, we continue to evaluate opportunities and actions that preserve fuel diversity, lower costs for our customers, and contribute towards long-term GHG reductions. Our plan is to work with our industry partners, environmental groups, and the State of Wisconsin, with a goal of reducing CO₂ emissions by approximately 40% below 2005 levels by 2030. We have implemented and continue to evaluate numerous options in order to meet our CO₂ reduction goal, such as increased use of existing natural gas combined cycle units, co-firing or switching to natural gas in existing coal-fired units, reduced operation or retirement of existing coal-fired units, addition of new renewable energy resources (wind, solar), and consideration of supply and demand-side energy efficiency and distributed generation. As a result of our generation reshaping plan, we expect to retire 1,800 MW of coal generation by 2020, including Pleasant Prairie power plant (now retired), PIPP, Pulliam power plant, and the jointly-owned Edgewater Unit 4 generation units. See Note 5, Property, Plant, and Equipment, for more information. In addition, we are evaluating our goal, and possible subsequent actions, with respect to national and international efforts to reduce future GHG emissions in order to limit future global temperature increases to less than two degrees Celsius.

We are required to report our CO₂ equivalent emissions from our electric generating facilities under the EPA Greenhouse Gases Reporting Program. For 2017, we reported aggregated CO₂ equivalent emissions of 29.2 million metric tonnes to the EPA. The level of CO₂ and other GHG emissions varies from year to year and is dependent on the level of electric generation and mix of fuel sources, which is determined primarily by demand, the availability of the generating units, the unit cost of fuel consumed, and how our units are dispatched by MISO.

We are also required to report CO₂ equivalent amounts related to the natural gas that our natural gas utilities distribute and sell. For 2017, we reported aggregated CO₂ equivalent emissions of 26.6 million metric tonnes to the EPA.

Water Quality

Clean Water Act Cooling Water Intake Structure Rule

In August 2014, the EPA issued a final regulation under Section 316(b) of the Clean Water Act, which requires that the location, design, construction, and capacity of cooling water intake structures at existing power plants reflect the Best Technology Available (BTA) for minimizing adverse environmental impacts from both impingement (entrapping organisms on water intake screens) and entrainment (drawing organisms into water intake). The rule became effective in October 2014, and applies to all of our existing generating facilities with cooling water intake structures, except for the ERGS units, which were permitted under the rules governing new facilities.

Facility owners must select from seven compliance options available to meet the impingement mortality (IM) reduction standard. The rule requires state permitting agencies to make BTA determinations, subject to EPA oversight, for IM reduction over the next several years as facility permits are reissued. Based on our assessment, we believe that existing technologies at our generating facilities, except for Pulliam Units 7 and 8, satisfy the IM BTA requirements. We plan to retire Pulliam Units 7 and 8 as early as late 2018. Therefore, we are not planning to make alterations to the existing water intake at Pulliam Units 7 and 8. Based on the reissued WPDES permit for Weston, the WDNR will not require physical modifications to the Weston Unit 2 intake structure to meet the IM BTA requirements based on low capacity use of the unit.

BTA determinations must also be made by the WDNR and MDEQ to address entrainment mortality (EM) reduction on a site-specific basis taking into consideration several factors. We have received an EM BTA determination by the WDNR, with EPA concurrence, for our intake modification at Valley Power Plant. There has also been an interim EM BTA determination made by the WDNR as part of the reissued WPDES permit for Weston Units 3 and 4 and we intend to extrapolate these results to assess Weston Unit 2. The entrainment study and other technical information will be used by the DNR to make a final 316(b) determination during the next five year WPDES permit term. At this time, we expect that the WDNR will conclude that the existing cooling tower systems for Weston Units 3 and 4 are BTA for both impingement and entrainment reduction. In addition, the WDNR has initially indicated that based on the low capacity utilization of Weston Unit 2, no impingement mortality reduction technology will be required and further entrainment reduction will not be necessary. Due to our plans to retire Pulliam Units 7 and 8, PIPP, and Pleasant Prairie power plant (now retired), we do not believe that BTA determinations for EM will be necessary for these units. Although we currently believe that existing technologies at PWGS, and OC 5 through OC 8 satisfy the EM BTA requirements, BTA determinations to address EM reduction requirements will not be made until discharge permits are renewed for these units. Until that time, we cannot yet determine what, if any, intake structure or operational modifications will be required to meet the new EM BTA requirements for these units. During 2018, we will continue to evaluate options to address the EM BTA requirements for these units.

03/31/2018 Form 10-Q 25 WEC Energy Group, Inc.

We have also provided information to the WDNR and the MDEQ about planned unit retirements. Based on discussions with the MDEQ, if we submit a signed certification stating that PIPP will be retired no later than the end of the next permit cycle (assumed to be October 1, 2023), the EM BTA requirements will be waived. We expect to submit the letter identifying the last operating date for PIPP to the MDEQ during 2018, ahead of when the agency begins processing our pending application for the National Pollutant Discharge Elimination System permit reissuance. For Pulliam Units 7 and 8, we submitted our 2016 and 2017 entrainment studies to the WDNR in December 2017, with the application to renew our existing discharge permit.

We believe our fleet overall is well positioned to meet the new regulation and do not expect to incur significant costs to comply with this regulation.

Steam Electric Effluent Limitation Guidelines

The EPA's final steam electric effluent limitation guidelines (ELG) rule took effect in January 2016. Various petitions challenging the rule were consolidated and are pending in the United States Fifth Circuit Court of Appeals. In April 2017, the EPA issued an administrative stay of certain compliance deadlines while further reviewing the rule. In September 2017, the EPA issued a final rule ("Postponement Rule") to postpone the earliest compliance dates for the bottom ash transport water and wet flue gas desulfurizationwastewater requirements. This rule applies to wastewater discharges from our power plant processes in Wisconsin and Michigan. While the ELG compliance deadlines are postponed, the WDNR and the MDEQ have indicated that they will refrain from incorporating certain new requirements into any reissued discharge permits between 2018 and 2023.

After a final rule is back in effect, the WDNR and MDEQ have indicated that they will modify the state rules as necessary and incorporate the new requirements into our facility permits, which are renewed every five years. Our power plant facilities already have advanced wastewater treatment technologies installed that meet many of the discharge limits established by this rule. However, as currently constructed, the ELG rule will require additional wastewater treatment retrofits as well as installation of other equipment to minimize process water use.

The final rule would phase in new or more stringent requirements related to limits of arsenic, mercury, selenium, and nitrogen in wastewater discharged from wet scrubber systems. New requirements for wet scrubber wastewater treatment would require additional zero liquid discharge or other advanced treatment capital improvements for the OCPP and ERGS. The rule also would require dry fly ash handling, which is already in place at all of our power plants. Dry bottom ash transport systems are required by the new rule, and modifications would be required at OC 7, OC 8, and Weston Unit 3. We are beginning preliminary engineering for compliance with the rule and estimate approximately $70 million would be required to design and install these advanced treatment and bottom ash transport systems. This estimate reflects the planned retirements of certain of our generation plants as a result of our generation reshaping plan discussed in Climate Change above.

Land Quality

Manufactured Gas Plant Remediation

We have identified sites at which our utilities 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. Our natural gas utilities are responsible for the environmental remediation of these sites, some of which are in the EPA Superfund Alternative Approach Program. We are also working with various state jurisdictions in our investigation and remediation planning. These sites are at various stages of investigation, monitoring, remediation, and closure.

In addition, we are coordinating the investigation and cleanup of some of these sites subject to the jurisdiction of the EPA under what is called a "multisite" program. This program involves prioritizing the work to be done at the sites, preparation and approval of documents common to all of the sites, and use of a consistent approach in selecting remedies. At this time, we cannot estimate future remediation costs associated with these sites beyond those described below.

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.

03/31/2018 Form 10-Q 26 WEC Energy Group, Inc.

We have established the following regulatory assets and reserves related to manufactured gas plant sites:

(in millions)	March 31, 2018		December 31, 2017
Regulatory assets	$	668.2	$	676.6
Reserves for future remediation	617.2		617.2

Enforcement and Litigation Matters

We and our subsidiaries 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 effect on our financial condition or results of operations.

Consent Decrees

Wisconsin Public Service Corporation Consent Decree – Weston and Pulliam Power Plants

In November 2009, the EPA issued a NOV to WPS, which alleged violations of the CAA's New Source Review requirements relating to certain projects completed at the Weston and Pulliam plants from 1994 to 2009. WPS entered into a Consent Decree with the EPA resolving this NOV. This Consent Decree was entered by the United States District Court for the Eastern District of Wisconsin in March 2013.

WPS anticipates retiring Pulliam generating units 7 and 8 near the end of 2018 when certain transmission lines are completed. See Note 5, Property, Plant, and Equipment, for more information about the retirement.

Joint Ownership Power Plants Consent Decree – Columbia and Edgewater

In December 2009, the EPA issued a NOV to Wisconsin Power and Light, the operator of the Columbia and Edgewater plants, and the other joint owners of these plants, including Madison Gas and Electric, WE (former co-owner of an Edgewater unit), and WPS. The NOV alleged violations of the CAA's New Source Review requirements related to certain projects completed at those plants. WPS, along with Wisconsin Power and Light, Madison Gas and Electric, and WE, entered into a Consent Decree with the EPA resolving this NOV. This Consent Decree was entered by the United States District Court for the Western District of Wisconsin in June 2013.

As a result of the continued implementation of the Consent Decree related to the jointly owned Columbia and Edgewater plants, retirement of the Edgewater 4 generating unit was probable at March 31, 2018. The plant must be retired by September 30, 2018. See Note 5, Property, Plant, and Equipment, for more information about the retirement.

NOTE 20—SUPPLEMENTAL CASH FLOW INFORMATION

	Three Months Ended March 31
(in millions)	2018			2017
Cash (paid) for interest, net of amount capitalized	$	(68.5	)	$	(56.6	)
Cash received for income taxes, net	0.3			8.9
Significant non-cash transactions
Accounts payable related to construction costs	74.9			116.4
Portion of Bostco real estate holdings sale financed with note receivable *	—			7.0
Amortization of deferred revenue	6.3			6.2

* See Note 3, Disposition, for more information on this sale.

Effective January 1, 2018, we adopted ASU 2016-18, Restricted Cash. Under this ASU, amounts generally described as restricted cash and restricted cash equivalents are included with cash and cash equivalents when reconciling the beginning-of-the period and end-of-the period total amounts shown on the statements of cash flows. As a result, we no longer present transfers between cash and cash equivalents and restricted cash and restricted cash equivalents in the statements of cash flows. Instead, changes in restricted cash are classified as either operating activities, investing activities or financing activities.

03/31/2018 Form 10-Q 27 WEC Energy Group, Inc.

The majority of our restricted cash consists of amounts held in the Integrys rabbi trust, which are used to fund participants' benefits under the Integrys deferred compensation plan and certain Integrys non-qualified pension plans. All assets held within the rabbi trust are restricted as they can only be withdrawn from the trust to make qualifying benefit payments. The adoption of ASU 2016-18 resulted in an increase of $7.5 million in net cash flows used by investing activities from what was previously reported for the quarter ended March 31, 2017.

See the following table for a reconciliation of cash and cash equivalents and restricted cash reported within the balance sheets to the sum of the total of the same amounts shown in the statements of cash flows at March 31.

(in millions)	2018		2017
Cash and cash equivalents	$	48.1	$	45.7
Restricted cash included in other current assets	—		0.8
Restricted cash included in other long term assets	23.6		26.9
Cash, cash equivalents, and restricted cash	$	71.7	$	73.4

Our statements of cash flows for the years ended December 31, 2017, 2016, and 2015 were retroactively restated from what was previously presented in our 2017 Annual Report on Form 10-K to reflect the adoption of ASU 2016-18. The impacts to our statements of cash flows from adoption of this standard are reflected in the table below.

	Year Ended December 31, 2017									Year Ended December 31, 2016									Year Ended December 31, 2015
(in millions)	2017 Form 10-K Cash Flows			Impact of ASU 2016-18			Cash Flows After Adoption			2017 Form 10-K Cash Flows			Impact of ASU 2016-18			Cash Flows After Adoption			2017 Form 10-K Cash Flows			Impact of ASU 2016-18			Cash Flows After Adoption
Operating Activities
Change in –
Other current assets	$	(6.0	)	$	(1.1	)	$	(7.1	)	$	103.1		$	0.1		$	103.2		$	(27.2	)	$	—		$	(27.2	)
Other, net	(197.5		)	0.1			(197.4		)	(53.8		)	0.2			(53.6		)	(209.1		)	1.5			(207.6		)
Net cash provided by operating activities	2,079.6			(1.0		)	2,078.6			2,103.5			0.3			2,103.8			1,293.6			1.5			1,295.1
Investing Activities
Withdrawal of restricted cash from rabbi trust for qualifying payments	19.5			(19.5		)	—			26.6			(26.6		)	—			1.4			(1.4		)	—
Proceeds from the sale of investments held in rabbi trust	—			8.7			8.7			—			1.7			1.7			—			126.9			126.9
Purchase of investments held in rabbi trust	—			(3.7		)	(3.7		)	—			(59.2		)	(59.2		)	—			(60.2		)	(60.2		)
Integrys acquisition, net of cash acquired	—			—			—			—			—			—			(1,329.9		)	30.8			(1,299.1		)
Other, net	12.0			—			12.0			3.0			—			3.0			57.0			(1.2		)	55.8
Net cash used in investing activities	(2,239.6		)	(14.5		)	(2,254.1		)	(1,270.1		)	(84.1		)	(1,354.2		)	(2,517.5		)	94.9			(2,422.6		)
Financing Activities
Other, net	(6.5		)	—			(6.5		)	(13.6		)	—			(13.6		)	(18.9		)	22.6			3.7
Net cash provided by (used in) financing activities	161.4			—			161.4			(845.7		)	—			(845.7		)	1,211.8			22.6			1,234.4
Net change in cash, cash equivalents, and restricted cash	1.4			(15.5		)	(14.1		)	(12.3		)	(83.8		)	(96.1		)	(12.1		)	119.0			106.9
Cash, cash equivalents, and restricted cash at beginning of period	37.5			35.2			72.7			49.8			119.0			168.8			61.9			—			61.9
Cash, cash equivalents, and restricted cash at end of period	$	38.9		$	19.7		$	58.6		$	37.5		$	35.2		$	72.7		$	49.8		$	119.0		$	168.8

03/31/2018 Form 10-Q 28 WEC Energy Group, Inc.

Effective January 1, 2018, we adopted ASU 2016-15, Classification of Certain Cash Receipts and Cash Payments. There are eight main provisions of this ASU for which current GAAP either was unclear or did not include specific guidance. The adoption of this guidance had no impact on our financial statements for the quarters ended March 31, 2018 and 2017.

ASU 2016-15 provides an accounting policy election for classifying distributions received from equity method investments. We adopted the cumulative earnings approach for classifying distributions received in the statements of cash flows. Under the cumulative earnings approach, we compare the distributions received to cumulative equity method earnings since inception. Any distributions received up to the amount of cumulative equity earnings are considered a return on investment and classified in operating activities. Any excess distributions are considered a return of investment and classified in investing activities. We did not receive any excess distributions for the quarters ended March 31, 2018 and 2017.

NOTE 21—REGULATORY ENVIRONMENT

Tax Cuts and Jobs Act of 2017

WEC Energy Group's regulated utilities deferred for return to ratepayers, through future refunds, bill credits, riders, or reductions in other regulatory assets, the estimated tax benefit of $2,450 million related to the Tax Legislation that was signed into law in December 2017. This tax benefit resulted from the revaluation of deferred taxes in December 2017. The current 2018 tax benefit related to the Tax Legislation, which reduced the corporate federal tax rate from a maximum of 35% to a 21% rate, effective January 1, 2018, is also being deferred for return to ratepayers.

We have not received a written order in any of our jurisdictions addressing the refunding of these amounts to date other than the rider approved in Illinois. See Variable Income Tax Adjustment Rider below for more information on this Illinois rider. Our proposed approach for the remaining jurisdictions is outlined below.

Wisconsin

In April 2018, the PSCW issued a preliminary determination regarding the benefits associated with the Tax Legislation. For our Wisconsin electric utility operations, the PSCW indicated that 80% of the current 2018 and 2019 tax benefits should be used to reduce certain regulatory assets at WE and WPS, with the remaining 20% returned to electric customers in the form of bill credits. For our Wisconsin natural gas utility operations, the PSCW indicated that 100% of current 2018 and 2019 tax benefits should be returned to natural gas customers in the form of bill credits. Regarding the net tax benefit associated with the revaluation of deferred taxes, amortization required in accordance with normalization accounting for our electric utilities should be used to reduce certain regulatory assets, while the timing and method of returning the remaining net tax benefit associated with the revaluation of deferred taxes was not addressed and will be determined in a future rate proceeding. Until we receive the final written order, the specific terms are subject to change.

Michigan

In February 2018, the MPSC issued an order requiring Michigan utilities to make three filings related to the Tax Legislation. The first of those filings, which was filed in March 2018, prospectively addresses the impact on base rates for the change in tax expense resulting from the federal tax rate reduction from 35% to 21%. For UMERC and MGU, the proposed approach is to provide a volumetric bill credit, subject to reconciliation and true up. The second filing will be due 30 days after the MPSC issues an order on the first filing and is required to address the impact on base rates for the change in tax expense resulting from the federal tax rate reduction from 35% to 21% from January 1, 2018, until the effective date of the initial filing. The third filing, which is due in October 2018, will address the remaining impacts of the Tax Legislation on base rates - most notably the re-measurement of deferred tax balances. UMERC and MGU have not yet made a proposal on the second and third filings.

WE, which serves one retail electric customer in Michigan, has reached a settlement with that customer. That settlement has been filed with the MPSC in March 2018 and addresses all base rate impacts of the Tax Legislation.

Minnesota

MERC is currently in an active rate case for 2018 and expects to address all aspects of the Tax Legislation, including the re-measurement of deferred tax balances, in that rate case. MERC expects that all impacts of the Tax Legislation will be incorporated into base rates when they are approved by the MPUC during the active rate proceeding.

03/31/2018 Form 10-Q 29 WEC Energy Group, Inc.

Wisconsin Electric Power Company, Wisconsin Gas LLC, and Wisconsin Public Service Corporation

2018 and 2019 Rates

During April 2017, WE, WG, and WPS filed an application with the PSCW for approval of a settlement agreement they made with several of their commercial and industrial customers regarding 2018 and 2019 base rates. In September 2017, the PSCW issued an order that approved the settlement agreement, which will freeze base rates through 2019 for electric, gas, and steam customers of WE, WG, and WPS. Based on the PSCW order, the authorized ROE for WE, WG, and WPS remains at 10.2%, 10.3%, and 10.0%, respectively, and the current capital cost structure for all of our Wisconsin utilities will remain unchanged through 2019. Various intervenors had filed requests for rehearing, all of which have been denied.

In addition to freezing base rates, the settlement agreement extends and expands the electric real-time market pricing program options for large commercial and industrial customers and mitigates the continued growth of certain escrowed costs at WE during the base rate freeze period by accelerating the recognition of certain tax benefits. WE will flow through the tax benefit of its repair-related deferred tax liabilities in 2018 and 2019, to maintain certain regulatory asset balances at their December 31, 2017 levels. While WE would typically follow the normalization accounting method and utilize the tax benefits of the deferred tax liabilities in rate making as an offset to rate base, benefiting customers over time, the federal tax code does allow for passing these tax repair-related benefits to ratepayers much sooner using the flow through accounting method. The flow through treatment of the repair related deferred tax liabilities offsets the negative income statement impact of holding the regulatory assets level, resulting in no change to net income.

The agreement also allows WPS to extend through 2019, the deferral for the revenue requirement of ReACT™ costs above the authorized $275.0 million level, and other deferrals related to WPS's electric real-time market pricing program and network transmission expenses. The total cost of the ReACT™ project, excluding $51 million of AFUDC, is currently estimated to be $342 million.

Pursuant to the settlement agreement, WPS also agreed to adopt, beginning in 2018, the earnings sharing mechanism that has been in place for WE and WG since January 2016, and all three utilities agreed to keep the mechanism in place through 2019. Under this earnings sharing mechanism, if WE, WG, or WPS earns above its authorized ROE, 50% of the first 50 basis points of additional utility earnings must be shared with customers. All utility earnings above the first 50 basis points must also be shared with customers.

Acquisition of a Wind Energy Generation Facility in Wisconsin

In October 2017, WPS, along with two other unaffiliated utilities, entered into an agreement to purchase the Forward Wind Energy Center, which consists of 86 wind turbines located in Wisconsin with a total capacity of 129 MW. The FERC approved the transaction in January 2018, and the PSCW approved the transaction in March 2018. The transaction closed on April 2, 2018. See Note 2, Acquisitions, for more information.

Natural Gas Storage Facilities in Michigan

In January 2017, we signed an agreement for the acquisition of Bluewater. Bluewater owns natural gas storage facilities in Michigan that are providing approximately one-third of the current storage needs for the natural gas operations of WE, WG, and WPS. As a result of this agreement, WE, WG, and WPS filed a request with the PSCW in February 2017 for a declaratory ruling on various items associated with the storage facilities. In the filing, WE, WG, and WPS requested that the PSCW review and confirm the reasonableness and prudency of their potential long-term storage service agreements and interstate natural gas transportation contracts related to the storage facilities. WE, WG, and WPS also requested approval to amend our Affiliated Interest Agreement to ensure WBS and our other subsidiaries could provide services to the storage facilities. The PSCW granted, subject to various conditions, these declarations and approvals, and we acquired Bluewater on June 30, 2017. In September 2017, WE, WG, and WPS finalized the long-term service agreements for the natural gas storage, which were approved by the PSCW in November 2017. See Note 2, Acquisitions, for more information.

03/31/2018 Form 10-Q 30 WEC Energy Group, Inc.

The Peoples Gas Light and Coke Company and North Shore Gas Company

Illinois Proceedings

In December 2015, the ICC ordered a series of stakeholder workshops to evaluate PGL's SMP. This ICC action did not impact PGL's ongoing work to modernize and maintain the safety of its natural gas distribution system, but it instead provided the ICC with an opportunity to analyze long-term elements of the program through the stakeholder workshops. The workshops were completed in March 2016. In July 2016, the ICC initiated a proceeding to review, among other things, the planning, reporting, and monitoring of the program, including the target end date for the program, and issued a final order in January 2018. The order did not have a significant impact on PGL's existing SMP design and execution. An appeal related to the final order was filed by the Illinois Attorney General in April 2018.

Qualifying Infrastructure Plant Rider

In July 2013, Illinois Public Act 98-0057, The Natural Gas Consumer, Safety & Reliability Act, became law. This law provides PGL with a cost recovery mechanism that allows collection, through a surcharge on customer bills, of prudently incurred costs to upgrade Illinois natural gas infrastructure. In September 2013, PGL filed with the ICC requesting the proposed rider, which was approved in January 2014.

PGL's QIP rider is subject to an annual reconciliation whereby costs are reviewed for accuracy and prudency. In March 2018, PGL filed its 2017 reconciliation with the ICC, which, along with the 2016 and 2015 reconciliations, are still pending. In February 2018, PGL agreed to a settlement of the 2014 reconciliation, which includes a rate base reduction of $5.4 million and a $4.7 million refund to ratepayers.

As of March 31, 2018, there can be no assurance that all costs incurred under PGL's QIP rider during the open reconciliation years will be deemed recoverable by the ICC.

Variable Income Tax Adjustment Rider

In April 2018, the ICC approved the VITA proposed by PGL and NSG. The VITA recovers or refunds changes in income tax expense resulting from differences in income tax rates and amortization of deferred tax excesses and deficiencies (in accordance with the Tax Legislation) from the amounts used in the Company's last rate case effective January 25, 2018. See Note 10, Income Taxes, for more information.

Minnesota Energy Resources Corporation

2018 Minnesota Rate Case

In October 2017, MERC initiated a rate proceeding with the MPUC to increase retail natural gas rates $12.6 million (5.05%). MERC's request reflected a 10.3% ROE and a common equity component average of 50.9%. In November 2017, the MPUC approved an interim rate order, effective January 1, 2018, authorizing a retail natural gas rate increase of $9.5 million (3.78%). In March 2018, to reflect changes in MERC's effective tax rate as a result of the enactment of the Tax Legislation, the MPUC approved a $2.5 million reduction in interim retail natural gas rates to $7.0 million (2.81%), effective April 1, 2018. The interim rates reflect a 9.1% ROE and a common equity component average of 50.9%. The interim rate increase is subject to refund pending the final written rate order, which is expected in the first half of 2019.

Upper Michigan Energy Resources Corporation

Formation of Upper Michigan Energy Resources Corporation

In December 2016, both the MPSC and the PSCW approved the operation of UMERC as a stand-alone utility in the Upper Peninsula of Michigan, and UMERC became operational effective January 1, 2017. This utility holds the electric and natural gas distribution assets, previously held by WE and WPS, located in the Upper Peninsula of Michigan.

03/31/2018 Form 10-Q 31 WEC Energy Group, Inc.

In August 2016, we entered into an agreement with the Tilden Mining Company (Tilden), under which Tilden will purchase electric power from UMERC for its iron ore mine for 20 years, contingent upon UMERC's construction of approximately 180 MW of natural gas-fired generation in the Upper Peninsula of Michigan.

In October 2017, the MPSC approved both the agreement with Tilden and UMERC's application for a certificate of necessity to begin construction of the proposed generation. The estimated cost of this project is $266 million ($277 million with AFUDC), 50% of which is expected to be recovered from Tilden, with the remaining 50% expected to be recovered from UMERC's other utility customers. The new units are expected to begin commercial operation by mid-2019. Upon receiving the MPSC's approval, retirement of the PIPP generating units became probable. As a result of a MISO ruling received in April 2018, the PIPP units must be retired no later than May 31, 2019. Tilden will remain a customer of WE until this new generation begins commercial operation.

NOTE 22—NEW ACCOUNTING PRONOUNCEMENTS

Leases

In February 2016, the FASB issued ASU 2016-02, Leases. This guidance is effective for fiscal years, and interim periods within those fiscal years, beginning after December 15, 2018, and will be applied using a modified retrospective approach. The main provision of this ASU is that lessees will be required to recognize lease assets and lease liabilities for most leases, including those classified as operating leases under GAAP. We are currently assessing the effects this guidance may have on our financial statements.

Financial Instruments Credit Losses

In June 2016, the FASB issued ASU 2016-13, Measurement of Credit Losses on Financial Instruments. This guidance is effective for fiscal years, and interim periods within those fiscal years, beginning after December 15, 2019. This ASU introduces a new impairment model known as the current expected credit loss model. The ASU requires a financial asset measured at amortized cost to be presented at the net amount expected to be collected. Previously, recognition of the full amount of credit losses was generally delayed until the loss was probable of occurring. We are currently assessing the effects this guidance may have on our financial statements.

03/31/2018 Form 10-Q 32 WEC Energy Group, Inc.

ITEM 2. MANAGEMENT'S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND RESULTS OF OPERATIONS

CORPORATE DEVELOPMENTS

The following discussion should be read in conjunction with the accompanying financial statements and related notes and our Annual Report on Form 10-K for the year ended December 31, 2017.

Introduction

We are a diversified holding company with natural gas and electric utility operations (serving customers in Wisconsin, Illinois, Michigan, and Minnesota), an approximately 60% equity ownership interest in American Transmission Company LLC (ATC) (a for-profit electric transmission company regulated by the FERC and certain state regulatory commissions), and non-utility energy infrastructure operations through We Power (which owns generation assets in Wisconsin) and Bluewater (which owns underground natural gas storage facilities in Michigan).

Corporate Strategy

Our goal is to continue to build and sustain long-term value for our shareholders and customers by focusing on the fundamentals of our business: reliability; operating efficiency; financial discipline; customer care; and safety.

Reshaping Our Generation Fleet

The planned reshaping of our generation fleet will balance reliability and customer cost with environmental stewardship. Taken as a whole, this plan should reduce costs to customers, preserve fuel diversity, and lower carbon emissions. Generation reshaping includes retiring older fossil fuel generation units, building state-of-the-art natural gas generation, and investing in cost-effective zero-carbon generation with a goal of reducing CO₂ emissions by approximately 40% below 2005 levels by 2030. We expect to retire approximately 1,800 MW of coal generation by 2020, and add additional natural gas-fired generating units and renewable generation, including utility-scale solar projects. Our 1,190 MW Pleasant Prairie power plant was retired in April 2018. The physical dismantlement of the Pleasant Prairie power plant will not occur immediately. It may take several years to finalize long-term plans for the site. See Note 5, Property, Plant, and Equipment, for information related to the Pleasant Prairie power plant retirement and planned retirements of certain of our other coal-fueled power plants.

Reliability

We have made significant reliability-related investments in recent years, and plan to continue strengthening and modernizing our generation fleet and distribution networks to further improve reliability. Our investments, coupled with our commitment to operating efficiency and customer care, resulted in We Energies being recognized by PA Consulting Group, an independent consulting firm, as the most reliable utility in the United States in 2017 and, for the seventh year in a row, as the most reliable utility in the Midwest.

Below are a few examples of reliability projects that are currently underway.

• Upper Michigan Energy Resources Corporation (UMERC), our Michigan electric and natural gas utility, is moving forward with its long-term generation solution for electric reliability in the Upper Peninsula of Michigan. The plan calls for UMERC to construct and operate approximately 180 MW of natural gas-fueled generation located in the Upper Peninsula. The new generation is expected to achieve commercial operation by mid-2019 and provide the region with affordable, reliable electricity that generates less emissions than the Presque Isle power plant (PIPP). In accordance with a written approval letter received from the Midcontinent Independent System Operator, we must retire PIPP by May 31, 2019.

• The Peoples Gas Light and Coke Company continues to work on its Natural Gas System Modernization Program, which primarily involves replacing old cast and ductile iron pipes and facilities in Chicago’s natural gas delivery system with modern polyethylene pipes to reinforce the long-term safety and reliability of the system.

• Wisconsin Public Service Corporation (WPS) continues work on its System Modernization and Reliability Project, which involves modernizing parts of its electric distribution system, including burying or upgrading lines. The project focuses on constructing

03/31/2018 Form 10-Q 33 WEC Energy Group, Inc.

facilities to improve the reliability of electric service WPS provides to its customers. WPS, Wisconsin Electric Power Company and Wisconsin Gas LLC also continue to upgrade their electric and natural gas distribution systems to enhance reliability.

Operating Efficiency

We continually look for ways to optimize the operating efficiency of our company. For example, we are making progress on our Advanced Metering Infrastructure 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 our utilities and our customers. This program reduces the manual effort for disconnects and reconnects and enhances outage management capabilities.

We continue to focus on integrating and improving business processes and consolidating our IT infrastructure across all of our companies. We expect these efforts to continue to drive operational efficiency and to put us in position to effectively support plans for future growth.

Financial Discipline

A strong adherence to financial discipline is essential to meeting our earnings projections and maintaining a strong balance sheet, stable cash flows, a growing dividend, 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, equipment, and entire business units, that are no longer strategic to operations, are not performing as intended, or have an unacceptable risk profile.

• See Note 2, Acquisitions, for information about our acquisitions of natural gas storage facilities in Michigan and a portion of a wind energy generation facility in Wisconsin.

• See Note 3, Disposition, for information on the sale of Bostco LLC's real estate holdings.

Our investment focus remains in our regulated utility and non-utility energy infrastructure businesses, as well as our investment in ATC. We expect total capital expenditures for our regulated utility and non-utility energy infrastructure businesses to be almost $12 billion from 2018 to 2022. Specific projects are discussed in more detail below under Liquidity and Capital Resources.

From 2018 to 2022, we expect capital contributions to ATC and ATC Holdco to be approximately $280 million. ATC Holdco is a separate entity formed in December 2016 to invest in transmission-related projects outside of ATC's traditional footprint. Capital investments at ATC and ATC Holdco will be funded utilizing these capital contributions, in addition to cash generated from operations and debt. We currently forecast that our share of ATC's and ATC Holdco's projected capital expenditures over the next five years will be $1.3 billion inside the traditional ATC footprint and $300 million outside of the traditional ATC footprint.

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 embracing constructive change, demonstrating personal responsibility for results, leveraging our capabilities and expertise, and using creative solutions to meet or exceed our customers’ expectations.

One example of how we obtain feedback from our customers is through our "We Care" calls, through which employees of our utility subsidiaries contact customers after a completed service call. Customer satisfaction is a priority, and making "We Care" calls is one of the main methods we use to gauge our performance to improve customer satisfaction.

Safety

We have a long-standing commitment to both workplace and public safety, and under our "Target Zero" mission, we have an ultimate goal of zero incidents, accidents, and injuries. We also set goals around injury-prevention activities that raise awareness and facilitate conversations about employee safety. 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.

03/31/2018 Form 10-Q 34 WEC Energy Group, Inc.

RESULTS OF OPERATIONS

THREE MONTHS ENDED MARCH 31, 2018

Consolidated Earnings

The following table compares our consolidated results for the first quarter of 2018 with the first quarter of 2017, including favorable or better, "B", and unfavorable or worse, "W", variances:

	Three Months Ended March 31
(in millions, except per share data)	2018			2017			B (W)			Change Related to Flow Through of Tax Repairs			Change Related to Tax Legislation			Remaining Change B (W)
Wisconsin	$	273.7		$	329.5		$	(55.8	)	$	(35.1	)	$	(50.9	)	$	30.2
Illinois	147.6			156.7			(9.1		)	—			(15.9		)	6.8
Other states	36.2			33.5			2.7			—			(5.5		)	8.2
Non-utility energy infrastructure	93.0			97.4			(4.4		)	—			(12.6		)	8.2
Corporate and other	(5.4		)	(2.4		)	(3.0		)	—			—			(3.0		)
Total operating income	545.1			614.7			(69.6		)	(35.1		)	(84.9		)	50.4
Equity in earnings of transmission affiliates	32.8			41.9			(9.1		)	—			(10.7		)	1.6
Other income, net	7.5			18.3			(10.8		)	—			—			(10.8		)
Interest expense	106.7			104.7			(2.0		)	—			—			(2.0		)
Income before income taxes	478.7			570.2			(91.5		)	(35.1		)	(95.6		)	39.2
Income tax expense	88.3			213.3			125.0			35.1			92.0			(2.1		)
Preferred stock dividends of subsidiary	0.3			0.3			—			—			—			—
Net income attributed to common shareholders	$	390.1		$	356.6		$	33.5		$	—		$	(3.6	)	$	37.1
Diluted earnings per share	$	1.23		$	1.12		$	0.11

Earnings increased $33.5 million during the first quarter of 2018, compared with the same quarter in 2017. The table above shows the income statement impact associated with the flow through of tax repairs beginning January 1, 2018 and the Tax Legislation signed into law in December 2017. As shown in the table above, the changes related to these items did not have a significant impact on net income. See Note 10, Income Taxes, and Note 21, Regulatory Environment, for more information.

The significant factors impacting the remaining increase in earnings were:

• A $30.2 million pre-tax ($21.9 million after tax) remaining increase in operating income at the Wisconsin segment. The increase was driven by higher electric and natural gas margins, which were primarily due to higher sales volumes as a result of the colder winter weather. Also contributing to the increase were lower operating expenses during the first quarter of 2018.

• An $8.2 million pre-tax ($6.0 million after tax) remaining increase in operating income at the other states segment. The increase was driven by higher natural gas margins, which were primarily due to higher sales volumes as a result of the colder winter weather during the first quarter of 2018.

• An $8.2 million pre-tax ($6.0 million after tax) remaining increase in operating income at the non-utility energy infrastructure segment, primarily driven by the inclusion of the operations of Bluewater following its acquisition on June 30, 2017.

• A $6.8 million pre-tax ($4.9 million after tax) remaining increase in operating income at the Illinois segment. The increase was driven by higher natural gas margins at PGL due to continued capital investment in the SMP project under its QIP rider.

These increases in earnings were partially offset by a $10.8 million pre-tax ($7.8 million after tax) decrease in other income, net, driven by a decrease in gains on investments held in the rabbi trust.

03/31/2018 Form 10-Q 35 WEC Energy Group, Inc.

Non-GAAP Financial Measure

The discussions below address the operating income contribution of each of our segments and include 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 margin (electric revenues less fuel and purchased power costs) and natural gas margin (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 more meaningful basis for evaluating utility operations than operating revenues 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 segments 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 our segment operating performance. Operating income for the first quarter of 2018 and 2017 for each of our segments is presented in the “Consolidated Earnings” table above.

Each applicable segment operating income discussion below includes a table that provides the calculation of electric margins and natural gas margins, as applicable, along with a reconciliation to segment operating income.

Wisconsin Segment Contribution to Operating Income

	Three Months Ended March 31
(in millions)	2018		2017		B (W)
Electric revenues	$	1,069.1	$	1,115.3	$	(46.2	)
Fuel and purchased power	352.3		350.5		(1.8		)
Total electric margins	716.8		764.8		(48.0		)
Natural gas revenues	520.0		496.8		23.2
Cost of natural gas sold	319.7		296.6		(23.1		)
Total natural gas margins	200.3		200.2		0.1
Total electric and natural gas margins	917.1		965.0		(47.9		)
Other operation and maintenance	468.5		465.7		(2.8		)
Depreciation and amortization	135.1		129.3		(5.8		)
Property and revenue taxes	39.8		40.5		0.7
Operating income	$	273.7	$	329.5	$	(55.8	)

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

	Three Months Ended March 31
(in millions)	2018		2017		B (W)
Operation and maintenance not included in line items below	$	177.0	$	189.7	$	12.7
We Power (1)	127.2		127.6		0.4
Transmission (2)	104.7		103.9		(0.8		)
Transmission expense related to the flow through of tax repairs (3)	14.7		—		(14.7		)
Regulatory amortizations and other pass through expenses (4)	44.9		44.5		(0.4		)
Total other operation and maintenance	$	468.5	$	465.7	$	(2.8	)

⁽¹⁾  Represents costs associated with the We Power generation units, including operating and maintenance costs incurred by WE, as well as the lease payments that are billed from We Power to WE and then recovered in WE's rates. During the three months ended March 31, 2018 and 2017, $110.5 million and $124.7 million, respectively, of both lease and operating and maintenance costs were billed to or incurred by WE, with the difference in costs billed or incurred and expenses recognized, either deferred or deducted from the regulatory asset.

03/31/2018 Form 10-Q 36 WEC Energy Group, Inc.

⁽²⁾  The PSCW has approved escrow accounting for ATC and MISO network transmission expenses for our Wisconsin electric utilities. As a result, WE and WPS defer as a regulatory asset or liability the differences between actual transmission costs and those included in rates until recovery or refund is authorized in a future rate proceeding. During the three months ended March 31, 2018 and 2017, $94.3 million and $82.9 million, respectively, of costs were billed by transmission providers to our electric utilities.

⁽³⁾  Represents additional transmission expense associated with WE's flow through of tax benefits of its repair-related deferred tax liabilities starting in 2018, in accordance with a settlement agreement with the PSCW, to maintain certain regulatory asset balances at their December 31, 2017 levels. See Note 21, Regulatory Environment, for more information.

⁽⁴⁾  Regulatory amortizations and other pass through expenses are substantially offset in margins and therefore do not have a significant impact on operating income.

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

	Three Months Ended March 31
	MWh (in thousands)
Electric Sales Volumes	2018	2017	B (W)
Customer Class
Residential	2,716.9	2,598.3	118.6
Small commercial and industrial *	3,194.3	3,192.6	1.7
Large commercial and industrial *	3,113.4	3,080.4	33.0
Other	46.2	47.2	(1.0	)
Total retail *	9,070.8	8,918.5	152.3
Wholesale	856.9	942.9	(86.0	)
Resale	2,443.6	2,277.1	166.5
Total sales in MWh *	12,371.3	12,138.5	232.8

* Includes distribution sales for customers who purchased power from an alternative electric supplier in Michigan.

	Three Months Ended March 31
	Therms (in millions)
Natural Gas Sales Volumes	2018	2017	B (W)
Customer Class
Residential	524.3	467.5	56.8
Commercial and industrial	316.8	280.8	36.0
Total retail	841.1	748.3	92.8
Transport	413.0	382.7	30.3
Total sales in therms	1,254.1	1,131.0	123.1

	Three Months Ended March 31
	Degree Days
Weather	2018	2017	B(W)
WE and WG (1)
Heating (3,255 normal)	3,225	2,849	376
WPS (2)
Heating (3,624 normal)	3,636	3,273	363
UMERC (3)
Heating (3,931 normal)	4,036	3,662	374

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

⁽²⁾  Normal degree days are based on a 20-year moving average of monthly temperatures from the Green Bay, Wisconsin weather station.

⁽³⁾  Normal degree days are based on a 20-year moving average of monthly temperatures from the Iron Mountain, Michigan weather station.

03/31/2018 Form 10-Q 37 WEC Energy Group, Inc.

Electric Utility Margins

Electric utility margins at the Wisconsin segment decreased $48.0 million during the first quarter of 2018, compared with the same quarter in 2017. The significant factors impacting the lower electric utility margins were:

• A $33.8 million decrease in margins related to amounts expected to be returned to customers through refunds, bill credits, or reductions in other regulatory assets, driven by the Tax Legislation signed into law in December 2017. See Note 10, Income Taxes, and Note 21, Regulatory Environment, for more information.

• A $20.4 million decrease in margins related to a settlement agreement with the PSCW to flow through WE's tax benefit of its repair-related deferred tax liabilities through reductions in certain regulatory assets, as discussed in the table above and in Note 21, Regulatory Environment.

• A $3.6 million decrease in wholesale margins driven both by reduced capacity rates reflecting the Tax Legislation signed into law in December 2017 as well as lower sales volumes at WPS.

These decreases in margins were partially offset by a $14.6 million increase related to higher retail sales volumes during the first quarter of 2018, primarily driven by colder winter weather. As measured by heating degree days, the first quarter of 2018 was 13.2% and 11.1% colder than the same quarter in 2017 in the Milwaukee area and Green Bay areas, respectively.

Natural Gas Utility Margins

Natural gas utility margins at the Wisconsin segment increased $0.1 million during the first quarter of 2018, compared with the same quarter in 2017. The most significant factor impacting the higher natural gas utility margins was a $17.4 million increase in sales volumes, primarily driven by colder winter weather, higher overall retail use per customer, and customer growth. This increase in margins was substantially offset by $17.1 million of amounts expected to be returned to customers through refunds, bill credits, or reductions in other regulatory assets, driven by the Tax Legislation signed into law in December 2017.

Operating Income

Operating income at the Wisconsin segment decreased $55.8 million during the first quarter of 2018, compared with the same quarter in 2017. This decrease was driven by the $47.9 million of lower net margins discussed above and $7.9 million of higher operating expenses (which include other operation and maintenance, depreciation and amortization, and property and revenues taxes).

The significant factors impacting the increase in operating expenses during the first quarter of 2018, compared with the same quarter in 2017, were:

• A $14.7 million increase in transmission expense related to the flow through of tax repairs, as discussed in the table above.

• A $5.8 million increase in depreciation and amortization driven by an overall increase in utility plant in service, WBS's transfer of an information technology project to WPS in June 2017, and the implementation of an enterprise resource planning system in January 2018.

These increases in operating expenses were partially offset by:

• A $4.9 million decrease in benefit costs.

• A $4.1 million decrease in expenses at our plants, primarily related to the winding down of operations in anticipation of expected plant retirements. This resulted in lower maintenance and labor costs during the first quarter of 2018. See Note 5, Property, Plant, and Equipment, for more information on the plant retirements.

• A $2.0 million decrease in electric and natural gas distribution expenses, primarily related to lower storm damage.

03/31/2018 Form 10-Q 38 WEC Energy Group, Inc.

Illinois Segment Contribution to Operating Income

	Three Months Ended March 31
(in millions)	2018		2017		B (W)
Natural gas revenues	$	507.3	$	525.3	$	(18.0	)
Cost of natural gas sold	201.7		207.7		6.0
Total natural gas margins	305.6		317.6		(12.0		)
Other operation and maintenance	112.2		119.6		7.4
Depreciation and amortization	40.9		36.2		(4.7		)
Property and revenue taxes	4.9		5.1		0.2
Operating income	$	147.6	$	156.7	$	(9.1	)

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

	Three Months Ended March 31
(in millions)	2018			2017		B (W)
Operation and maintenance not included in the line items below	$	73.7		$	76.5	$	2.8
Riders *	38.5			42.3		3.8
Regulatory amortizations *	(0.3		)	0.7		1.0
Other	0.3			0.1		(0.2		)
Total other operation and maintenance	$	112.2		$	119.6	$	7.4

* These riders and regulatory amortizations are substantially offset in margins and therefore do not have a significant impact on operating income.

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

	Three Months Ended March 31
	Therms (in millions)
Natural Gas Sales Volumes	2018	2017	B (W)
Customer Class
Residential	428.6	349.4	79.2
Commercial and industrial	168.4	143.3	25.1
Total retail	597.0	492.7	104.3
Transport	356.6	326.0	30.6
Total sales in therms	953.6	818.7	134.9

	Three Months Ended March 31
	Degree Days
Weather *	2018	2017	B (W)
Heating (3,137 Normal)	3,113	2,661	452

* Normal heating degree days are based on a 12-year moving average of monthly temperatures from Chicago's O'Hare Airport.

Natural Gas Utility Margins

Natural gas utility margins, net of the $3.8 million impact of the riders referenced in the table above, decreased $8.2 million during the first quarter of 2018, compared with the same quarter in 2017, driven by a $15.9 million decrease in margins related to amounts expected to be returned to customers through VITA in connection with the Tax Legislation signed into law in December 2017. See Note 10, Income Taxes, and Note 21, Regulatory Environment, for more information. The decrease was partially offset by an increase in revenue at PGL due to continued capital investment in the SMP project under its QIP rider. PGL currently recovers the costs related to the SMP through a surcharge on customer bills pursuant to an ICC approved QIP rider, which is in effect through 2023.

03/31/2018 Form 10-Q 39 WEC Energy Group, Inc.

Operating Income

Operating income at the Illinois segment decreased $9.1 million during the first quarter of 2018, compared with the same quarter in 2017. This decrease was due to the $8.2 million net decrease in margins discussed above, and a $0.9 million increase in operating expenses (which include other operation and maintenance, depreciation and amortization, and property and revenues taxes), net of the impact of the riders referenced in the table above. The increase in operating expenses was driven by higher depreciation expense at PGL primarily due to continued capital investment in the SMP project.

Other States Segment Contribution to Operating Income

	Three Months Ended March 31
(in millions)	2018		2017		B (W)
Natural gas revenues	$	169.9	$	157.9	$	12.0
Cost of natural gas sold	96.4		86.4		(10.0		)
Total natural gas margins	73.5		71.5		2.0
Other operation and maintenance	26.6		28.2		1.6
Depreciation and amortization	6.6		6.0		(0.6		)
Property and revenue taxes	4.1		3.8		(0.3		)
Operating income	$	36.2	$	33.5	$	2.7

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

	Three Months Ended March 31
(in millions)	2018		2017		B (W)
Operation and maintenance not included in line item below	$	17.4	$	19.4	$	2.0
Regulatory amortizations and other pass through expenses *	9.2		8.8		(0.4		)
Total other operation and maintenance	$	26.6	$	28.2	$	1.6

* Regulatory amortizations and other pass through expenses are substantially offset in margins and therefore do not have a significant impact on operating income.

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

	Three Months Ended March 31
	Therms (in millions)
Natural Gas Sales Volumes	2018	2017	B (W)
Customer Class
Residential	170.4	133.8	36.6
Commercial and industrial	103.8	83.9	19.9
Total retail	274.2	217.7	56.5
Transport	224.2	191.4	32.8
Total sales in therms	498.4	409.1	89.3

	Three Months Ended March 31
	Degree Days
Weather *	2018	2017	B (W)
MERC
Heating (3,872 Normal)	4,085	3,550	535
MGU
Heating (3,184 Normal)	3,135	2,717	418

* Normal heating degree days for MERC and MGU are based on a 20-year moving average and 15-year moving average, respectively, of monthly temperatures from various weather stations throughout their respective service territories.

03/31/2018 Form 10-Q 40 WEC Energy Group, Inc.

Natural Gas Utility Margins

Natural gas utility margins increased $2.0 million during the first quarter of 2018, compared to the same quarter last year. The increase was primarily driven by colder winter weather in the first quarter of 2018 as well as customer growth, partially offset by a $5.5 million decrease in margins related to amounts expected to be returned to customers through refunds, bill credits, or reductions in other regulatory assets, related to the Tax Legislation signed into law in December 2017. See Note 10, Income Taxes, and Note 21, Regulatory Environment, for more information.

Operating Income

Operating income at the other states segment increased $2.7 million during the first quarter of 2018, compared to the same quarter last year. This increase was driven by the $2.0 million increase in margins discussed above and a $0.7 million decrease in operating expenses. The decrease in operating expenses was primarily due to effective cost control measures.

Non-Utility Energy Infrastructure Segment Contribution to Operating Income

	Three Months Ended March 31
(in millions)	2018		2017		B (W)
Operating income	$	93.0	$	97.4	$	(4.4	)

Operating income at the non-utility energy infrastructure segment decreased $4.4 million, or 4.5%, when compared to the first quarter of 2017. The decrease was driven by a $12.6 million decrease in revenue related to the Tax Legislation signed into law in December 2017, partially offset by contributions from Bluewater. As a result of the Tax Legislation, the lease payments charged by We Power to WE were reduced. The reduction in the lease payments was offset by a decrease in income tax expense, resulting in no impact on net income. See Note 10, Income Taxes, and Note 21, Regulatory Environment, for more information. Bluewater, which was acquired on June 30, 2017, contributed $7.8 million to first quarter 2018 operating income. See Note 2, Acquisitions, for more informationon the acquisition of Bluewater.

Corporate and Other Segment Contribution to Operating Income

	Three Months Ended March 31
(in millions)	2018			2017			B (W)
Operating loss	$	(5.4	)	$	(2.4	)	$	(3.0	)

The operating loss at the corporate and other segment increased $3.0 million, when compared to the first quarter of 2017. We transferred assets from WBS, our centralized services company, to our regulated utilities in mid-2017 and the first quarter of 2018. Accordingly, the return on these assets is now recognized within our regulated utility operations.

Electric Transmission Segment Operations

	Three Months Ended March 31
(in millions)	2018		2017		B (W)
Equity in earnings of transmission affiliates	$	32.8	$	41.9	$	(9.1	)

Earnings from our ownership interests in transmission affiliates decreased $9.1 million during the first quarter of 2018, compared with the same quarter in 2017, primarily due to the Tax Legislation signed into law in December 2017. The impact of the Tax Legislation on our transmission affiliates did not affect our net income as it was offset by an equal reduction in our income tax expense. See Note 10, Income Taxes, and Note 21, Regulatory Environment, for more information. The decrease in equity earnings from the Tax Legislation was partially offset by increased equity earnings related to continued capital investment by our transmission affiliates.

03/31/2018 Form 10-Q 41 WEC Energy Group, Inc.

Consolidated Other Income, Net

	Three Months Ended March 31
(in millions)	2018		2017		B (W)
AFUDC – Equity	$	3.3	$	2.4	$	0.9
Other, net	4.2		15.9		(11.7		)
Other income, net	$	7.5	$	18.3	$	(10.8	)

Other income, net decreased by $10.8 million when compared to the first quarter of 2017. The decrease was driven by a $6.7 million decrease in gains on investments held in our rabbi trust during the first quarter of 2018, compared with the same period in 2017.

Consolidated Interest Expense

	Three Months Ended March 31
(in millions)	2018		2017		B (W)
Interest expense	$	106.7	$	104.7	$	(2.0	)

Interest expense increased $2.0 million during the quarter ended March 31, 2018, compared with the same quarter in 2017, primarily due to higher short-term debt balances and higher short-term debt rates. The increase in short-term debt balances was used for continued capital investments.

Consolidated Income Tax Expense

	Three Months Ended March 31
	2018		2017		B (W)
Effective tax rate	18.4	%	37.4	%	19.0	%

Our effective tax rate decreased by 19.0% when compared with the first quarter of 2017, primarily due to the impact of the Tax Legislation. Contributing 5% to the decrease in the effective tax rate is the flow through of tax repairs in connection with the Wisconsin rate settlement. See Note 10, Income Taxes, and Note 21, Regulatory Environment, for more information.

We expect our 2018 annual effective tax rate to be between 13% and 14%, which includes an estimated 8% effective tax rate benefit due to the flow through of tax repairs.

LIQUIDITY AND CAPITAL RESOURCES

Cash Flows

The following table summarizes our cash flows during the three months ended March 31:

(in millions)	2018			2017			Change in 2018 Over 2017
Cash provided by (used in):
Operating activities	$	894.0		$	714.6		$	179.4
Investing activities	(435.8		)	(333.1		)	(102.7		)
Financing activities	(445.1		)	(380.8		)	(64.3		)

Operating Activities

Net cash provided by operating activitiesincreased$179.4 million during the first quarter of 2018, compared with the same period in 2017, driven by:

• A $100.7 millionincrease in cash due to lower contributions and payments to our pension and OPEB plans during the first quarter of 2018, compared with the same period in 2017.

• A $100.3 million increase in cash related to higher overall collections from customers, primarily due to colder weather during the first quarter of 2018, compared with the same period in 2017.

03/31/2018 Form 10-Q 42 WEC Energy Group, Inc.

• A $17.9 million increase in cash from lower payments for operating and maintenance costs. During the first quarter of 2018, our payments related to employee benefits, plant operating and maintenance costs, and electric and natural gas distribution decreased.

These increases in net cash provided by operating activities were partially offset by a $28.5 million decrease in cash from customer prepayments and credit balancesdue to colder weather during the first quarter of 2018, compared with the same period in 2017. Customers used more energy than they paid for under budget billing programs during the first quarter of 2018.

Investing Activities

Net cash used in investing activitiesincreased$102.7 million during the first quarter of 2018, compared with the same period in 2017, driven by:

• A $109.9 million increase in cash paid for capital expenditures during the first quarter of 2018, compared with the same period in 2017, which is discussed in more detail below.

• A $12.3 million decrease in the proceeds received from the sale of assets and businesses during the first quarter of 2018, compared with the same period in 2017. See Note 3, Disposition, for more information.

These increases in net cash used in investing activities were partially offset by a $14.8 million decrease in our capital contributions to ATC and ATC Holdco during the first quarter of 2018, compared with the same period in 2017. Our capital contributions decreased due to the refunds ATC paid in 2017 as a result of the ATC ROE complaints filed with the FERC, which were partially funded by capital contributions. See Factors Affecting Results, Liquidity, and Capital Resources – Other Matters – American Transmission Company Allowed Return on Equity Complaints for more information.

Capital Expenditures

Capital expenditures by segment for the three months ended March 31 were as follows:

Reportable Segment (in millions)	2018		2017		Change in 2018 Over 2017
Wisconsin	$	284.1	$	199.0	$	85.1
Illinois	114.6		97.5		17.1
Other states	17.0		12.6		4.4
Non-utility energy infrastructure	3.9		5.2		(1.3		)
Corporate and other	20.0		15.4		4.6
Total capital expenditures	$	439.6	$	329.7	$	109.9

The increase in cash paid for capital expenditures at the Wisconsin segment during the first quarter of 2018, compared with the same period in 2017, was driven by a project to construct a new natural gas-fired generation facility in the Upper Peninsula of Michigan andupgrades to our electric and natural gas distribution systems. WPS's SMRP, the implementation of a new enterprise resource planning system, and various other software projects also contributed to the increase in our capital expenditures.

The increase in cash paid for capital expenditures at the Illinois segment during the first quarter of 2018, compared with the same period in 2017, was driven by increased construction activity related to PGL's SMP.

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

Financing Activities

Net cash used in financing activitiesincreased$64.3 million during the first quarter of 2018, compared with the same period in 2017, driven by:

• A $54.5 million increase in net repayments of commercial paper during the first quarter of 2018, compared with the same period in 2017.

03/31/2018 Form 10-Q 43 WEC Energy Group, Inc.

• A $10.1 million increase in dividends paid on our common stock during the first quarter of 2018, compared with the same period in 2017. In January 2018, our Board of Directors increased our quarterly dividend by $0.0325 per share effective with the first quarter of 2018 dividend payment.

Significant Financing Activities

For more information on our financing activities, see Note 7, Short-Term Debt and Lines of Credit, and Note 8, Long-Term Debt.

Capital Resources and Requirements

Capital Resources

Liquidity

We anticipate meeting our capital requirements for our existing operations through internally generated funds and short-term borrowings, supplemented by the issuance of intermediate or long-term debt securities, depending on market conditions and other factors.

We currently have access to the capital markets and have been able to generate funds internally and externally to meet our capital requirements. Our ability to attract the necessary financial capital at reasonable terms is critical to our overall strategic plan. We currently believe that we have adequate capacity to fund our operations for the foreseeable future through our existing borrowing arrangements, access to capital markets, and internally generated cash.

WEC Energy Group, WE, WG, WPS, and PGL maintain bank back-up credit facilities, which provide liquidity support for each company's 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. See Note 7, Short-Term Debt and Lines of Credit, for more information about these credit facilities.

The following table shows our capitalization structure as of March 31, 2018, as well as an adjusted capitalization structure that we believe is consistent with how a majority of the rating agencies currently view our 2007 Junior Notes:

(in millions)	Actual			Adjusted
Common equity	$	9,667.8		$	9,917.8
Preferred stock of subsidiary	30.4			30.4
Long-term debt (including current portion)	9,575.4			9,325.4
Short-term debt	1,200.3			1,200.3
Total capitalization	$	20,473.9		$	20,473.9
Total debt	$	10,775.7		$	10,525.7
Ratio of debt to total capitalization	52.6		%	51.4		%

Included in long-term debt on our balance sheet as of March 31, 2018, is $500.0 million principal amount of the 2007 Junior Notes. The adjusted presentation attributes $250.0 million of the 2007 Junior Notes to common equity and $250.0 million to long-term debt.

The adjusted presentation of our consolidated capitalization structure is included as a complement to our capitalization structure presented in accordance with GAAP. Management evaluates and manages our capitalization structure, including our total debt to total capitalization ratio, using the GAAP calculation as adjusted by the rating agency treatment of the 2007 Junior Notes. Therefore, we believe the non-GAAP adjusted presentation reflecting this treatment is useful and relevant to investors in understanding how management and the rating agencies evaluate our capitalization structure.

As of March 31, 2018, WE was the obligor under a series of tax-exempt pollution control refunding bonds with an outstanding principal amount of $80.0 million. In August 2009, WE terminated a letter of credit that provided credit and liquidity support for the bonds, which resulted in a mandatory tender of the bonds. WE purchased the bonds at par plus accrued interest to the date of

03/31/2018 Form 10-Q 44 WEC Energy Group, Inc.

purchase. As of March 31, 2018, the repurchased bonds were still outstanding but are not reported in our long-term debt since they are held by WE.

Working Capital

As of March 31, 2018, our current liabilities exceeded our current assets by $1,625.1 million. We do not expect this to have any impact on our liquidity since we believe we have adequate back-up lines of credit in place for our ongoing operations. We also believe that we can access the capital markets to finance our construction programs and to refinance current maturities of long-term debt.

Credit Rating Risk

We do not have any credit agreements that would require material changes in payment schedules or terminations as a result of a credit rating downgrade. However, we have certain agreements in the form of commodity contracts and employee benefit plans that could require collateral or a termination payment in the event of a credit rating change to below BBB- at S&P Global Ratings and/or Baa3 at Moody's Investors Service. 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.

In January 2018, Moody's downgraded the rating outlook for WG to negative from stable as a result of the new Tax Legislation. We do not believe the change in rating outlook will have a material impact on 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.

If we are unable to successfully take actions to manage any adverse impacts of the Tax Legislation, or if additional interpretations, regulations, amendments or technical corrections exacerbate the adverse impacts of the Tax Legislation, the legislation could result in credit rating agencies placing our or our subsidiaries’ credit ratings on negative outlook or downgrading our or our subsidiaries' credit ratings. Any such actions by credit rating agencies may make it more difficult and costly for us and our subsidiaries to issue future debt securities and certain other types of financing and could increase borrowing costs under our and our subsidiaries’ credit facilities.

Capital Requirements

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, impacts from the Tax Legislation, acquisition and development opportunities, market volatility, and economic trends. Our estimated capital expenditures and acquisitions for the next three years are as follows:

(in millions)	2018		2019		2020
Wisconsin	$	1,430.1	$	1,152.0	$	1,850.2
Illinois	633.8		629.2		676.5
Other states	99.6		116.1		110.6
Non-utility energy infrastructure	280.8		60.5		51.9
Corporate and other	20.7		13.2		0.8
Total	$	2,465.0	$	1,971.0	$	2,690.0

WPS is continuing work on the SMRP. This project includes modernizing parts of its electric distribution system, including burying or upgrading lines. The project focuses on constructing facilities to improve the reliability of electric service WPS provides to its customers. WPS expects to invest approximately $250 million between 2018 and 2021 on this project. WE, WPS, and WG will also

03/31/2018 Form 10-Q 45 WEC Energy Group, Inc.

continue to upgrade their electric and natural gas distribution systems to enhance reliability. These upgrades include the advanced metering infrastructure (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.

As part of our commitment to invest in zero-carbon generation, we plan to invest in utility scale solar of up to 350 MW within our Wisconsin segment. Solar generation technology has greatly improved, has become more cost-effective, and it complements our summer demand curve.

In connection with the formation of UMERC, we entered into an agreement withTilden Mining Companyunder which it will purchase electric power from UMERC for 20 years, contingent upon UMERC's construction of approximately 180 MW of natural gas-fired generation in the Upper Peninsula of Michigan. The new generation is expected to begin commercial operation by mid-2019. The estimated cost of this project is approximately $266 million ($277 million including AFUDC).See Note 21, Regulatory Environment, for more informationabout UMERC and this new generation.

PGL is continuing work on the SMP, a project under which PGL is replacing approximately 2,000 miles of Chicago's aging natural gas pipeline infrastructure. PGL currently recovers these costs through a surcharge on customer bills pursuant to an ICC approved QIP rider, which is in effect through 2023. PGL's projected average annual investment through 2020 is between $280 million and $300 million. See Note 21, Regulatory Environment, for more informationon the SMP.

We expect to provide total capital contributions to ATC (not included in the above table) of approximately $200 million from 2018 through 2020.

Common Stock Dividends

Our current quarterly dividend rate is $0.5525 per share, which equates to an annual dividend of $2.21 per share. For information related to our most recent common stock dividend declared, see Note 6, Common Equity.

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 financial guarantees and letters of credit that support construction projects, commodity contracts, and other payment obligations. 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. For additional information, see Note 7, Short-Term Debt and Lines of Credit, Note 13, Guarantees, and Note 18, Variable Interest Entities.

Contractual Obligations

For additional information about our commitments, see Contractual Obligations in Item 7. Management's Discussion and Analysis of Financial Condition and Results of Operations – Capital Resources and Requirements in our 2017 Annual Report on Form 10-K.

FACTORS AFFECTING RESULTS, LIQUIDITY, AND CAPITAL RESOURCES

The following is a discussion of certain factors that may affect our results of operations, liquidity, and capital resources. The following discussion should be read together with the information in Item 7. Management's Discussion and Analysis of Financial Condition and Results of Operations – Factors Affecting Results, Liquidity, and Capital Resources in our 2017 Annual Report on Form 10-K, which provides a more complete discussion of factors affecting us, including market risks and other significant risks, industry restructuring, environmental matters, critical accounting policies and estimates, and other matters.

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 include, but are not limited to, the regulatory recovery risk described below. 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 in our 2017 Annual Report on Form 10-K for a discussion of other significant risks applicable to us.

03/31/2018 Form 10-Q 46 WEC Energy Group, Inc.

Regulatory Recovery

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 specific orders or by a generic order issued by our regulators. Recovery of the deferred costs in future rates is subject to the review and approval by those regulators. We assume the risks and benefits of ultimate recovery of these items in future rates. If the recovery of the deferred costs, including those referenced below, 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.

We expect to request or have requested recovery of the costs related to the following projects discussed in recent or pending rate proceedings, orders, and investigations involving our utilities:

• In June 2016, the PSCW approved the deferral of costs related to WPS's ReACT™ project above the originally authorized $275.0 million level through 2017. The total cost of the ReACT™ project, excluding $51 million of AFUDC, is currently estimated to be $342 million. In September 2017, the PSCW approved an extension of this deferral through 2019 as part of a settlement agreement. See Note 21, Regulatory Environment, for more information. WPS will be required to obtain a separate approval for collection of these deferred costs in a future rate case.

• Prior to its acquisition, Integrys initiated an information technology project with the goal of improving the customer experience at its subsidiaries. Specifically, the project is expected to provide functional and technological benefits to the billing, call center, and credit collection functions. As of March 31, 2018, we had not received any significant disallowances of the costs incurred for this project. We will be required to obtain approval for the recovery of additional costs incurred through the completion of this long-term project.

• In January 2014, the ICC approved PGL's use of the QIP rider as a recovery mechanism for costs incurred related to investments in QIP. This rider is subject to an annual reconciliation whereby costs are reviewed for accuracy and prudency. In March 2018, PGL filed its 2017 reconciliation with the ICC, which, along with the 2016 and 2015 reconciliations, are still pending. In February 2018, PGL agreed to a settlement of the 2014 reconciliation, which includes a rate base reduction of $5.4 million and a $4.7 million refund to ratepayers. As of March 31, 2018, there can be no assurance that all costs incurred under the QIP rider during the open reconciliation years will be deemed recoverable by the ICC.

See Note 21, Regulatory Environment, for more information regarding recent and pending rate proceedings, orders, and investigations involving our utilities.

Environmental Matters

See Note 19, Commitments and Contingencies, for a discussion of certain environmental matters affecting us, including rules and regulations relating to air quality, water quality, land quality, and climate change.

Other Matters

Tax Cuts and Jobs Act of 2017

In December 2017, the Tax Legislation was signed into law. The FERC and our state public utility commissions are working with our utility subsidiaries to return any tax savings from the Tax Legislation to customers. If the amounts our regulators order our utility subsidiaries to return to customers exceed the actual tax savings realized or if our regulators require the tax savings to be applied in a manner other than we had expected, it could have a material adverse effect on our financial condition, results of operations, and cash flow. See Note 21, Regulatory Environment, for more information.

American Transmission Company Allowed Return on Equity Complaints

In November 2013, a group of MISO industrial customer organizations filed a complaint with the FERC requesting to reduce the base ROE used by MISO transmission owners, including ATC, from 12.2% to 9.15%. In October 2014, the FERC issued an order to hear the complaint on ROE and set a refund effective date retroactive to November 2013. In December 2015, the ALJ issued an initial decision

03/31/2018 Form 10-Q 47 WEC Energy Group, Inc.

recommending that ATC and all other MISO transmission owners be authorized to collect a base ROE of 10.32%, as well as the 0.5% incentive adder approved by the FERC in January 2015 for MISO transmission owners. The incentive adder only applies to revenues collected after January 6, 2015. In September 2016, the FERC issued a final order related to this complaint affirming the use of the ROE stated in the ALJ's initial decision, effective as of the order date, on a going-forward basis. The order also required ATC to provide refunds, with interest, for the 15-month refund period from November 12, 2013, through February 11, 2015. The refunds ATC provided to WE and WPS for transmission costs paid during the refund period reduced the regulatory assets recorded under the PSCW-approved escrow accounting for transmission expense and resulted in a net regulatory liability for WPS. See Note 16, Investment in Transmission Affiliates, for more information.

In February 2015, a second complaint was filed with the FERC requesting a reduction in the base ROE used by MISO transmission owners, including ATC, to 8.67%, with a refund effective date retroactive to February 12, 2015. In June 2016, the ALJ issued an initial decision recommending that ATC and all other MISO transmission owners be authorized to collect a base ROE of 9.7%, as well as the 0.5% incentive adder approved for MISO transmission owners. The ALJ's initial decision is not binding on the FERC and applies to revenues collected from February 12, 2015, through May 11, 2016. We are uncertain when a FERC order related to this matter will be issued.

The MISO transmission owners have filed various appeals related to several of the FERC orders with the D.C. Circuit Court of Appeals as well as requests for rehearing.

03/31/2018 Form 10-Q 48 WEC Energy Group, Inc.

ITEM 3. QUANTITATIVE AND QUALITATIVE DISCLOSURES ABOUT MARKET RISK

There have been no material changes related to market risk from the disclosures presented in our Annual Report on Form 10-K for the year ended December 31, 2017. In addition to the Form 10-K disclosures, see 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 in Item 2 of Part I of this report, as well as Note 11, Fair Value Measurements, Note 12, Derivative Instruments, and Note 13, Guarantees, in this report for information concerning our market risk exposures.

03/31/2018 Form 10-Q 49 WEC Energy Group, Inc.

ITEM 4. 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.

Changes in Internal Control Over Financial Reporting

During the first quarter of 2018, we completed an enterprise resource planning (ERP) system integration project to bring all of our subsidiaries onto a consolidated ERP system. Accordingly, we are modifying the design and documentation of certain internal control processes and procedures related to the integrated ERP system. We do not believe that the implementation of the ERP system will have an adverse effect on our internal control over financial reporting.

With the exception of the ERP system implementation described above, 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)) that materially affected, or are reasonably likely to materially affect, our internal control over financial reporting.

03/31/2018 Form 10-Q 50 WEC Energy Group, Inc.

PART II. OTHER INFORMATION

ITEM 1. LEGAL PROCEEDINGS

The following should be read in conjunction with Item 3. Legal Proceedings in Part I of our 2017 Annual Report on Form 10-K. See Note 19, Commitments and Contingencies, and Note 21, Regulatory Environment, in this report for more information on material legal proceedings and matters related to us and our subsidiaries.

In addition to those legal proceedings discussed in Note 19, Commitments and Contingencies, Note 21, 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 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 effect on our financial statements.

Environmental Matters

Sheboygan River Matter

We were contacted by the United States Department of Justice in March 2016 to commence discussions between WPS and the federal natural resource trustees to resolve WPS's alleged liability for natural resources damages (NRD) in the Sheboygan River related to the former Camp Marina manufactured gas plant site. WPS was originally notified about this claim in September 2012, but the WDNR chose not to be a party to the NRD claim negotiation in February 2014. However, the National Oceanic and Atmospheric Administration has co-equal trusteeship with the WDNR over the impacted Sheboygan River natural resources and pursued the NRD claim. Substantial remediation of the uplands at the legacy Sheboygan Camp Marina manufactured gas plant site has already occurred. We entered into a settlement agreement to resolve this matter, which was approved by the United States District Court for the Eastern District of Wisconsin on April 19, 2018. The terms of the settlement did not have a material impact on our financial statements. 

Manlove Field Matter

In September 2017, the Illinois Department of Natural Resources (Illinois DNR), Office of Oil and Gas Resource Management, issued a NOV to PGL related to a leak of natural gas that PGL identified at its Manlove Gas Storage Field in December 2016. PGL quickly contained the leak after it was discovered. The leak resulted in the migration of natural gas from a well located at the facility to the Mahomet Aquifer located in central Illinois, which may have impacted residential freshwater wells. PGL has been working with the potentially impacted homeowners and other residents that may have been impacted by the natural gas leak, as well as the Illinois DNR and other state agencies to investigate and remediate the impacts of the gas leak to the Mahomet Aquifer. In October 2017, the Illinois Attorney General (AG) filed a complaint against PGL alleging certain violations of the Illinois Environmental Protection Act and the Oil and Gas Act. PGL entered into an interim order with the State of Illinois in October 2017 whereby PGL agreed, among other things, to continue actions it was already undertaking proactively. In addition, in December 2017, the Illinois Environmental Protection Agency served a NOV to PGL alleging the same violations as the AG, and in January 2018, served a NOV alleging certain violations of Illinois air emission rules arising from the construction and operation of flaring equipment at the leak site. Both matters have been referred to the AG for enforcement.

In the complaint, as is customary in these types of actions, the AG cited to the statutory penalties allowed by law. Ultimately, the assessment of any penalties is at the AG’s discretion. In the event the AG wishes to consider penalties, we believe that PGL's high level of cooperation and quick action to remedy the situation and to work with the potentially impacted homeowners would be taken into account. At this time, we believe that civil penalties, if any, will not have a material impact on our financial statements.

Presque Isle Power Plant Matter

In March 2018, the EPA issued a Finding of Violation to WE regarding alleged violations of mercury emission limits for PIPP Units 5, 6, 8, and 9, as well as failing to conduct low emitting electric utility steam generating units mercury testing once every 12 months. WE observed atypical initial mercury test results in June 2017 and immediately began to troubleshoot the potential cause. WE found that the supplier of dry sorbent injection material for the air quality control system that controls mercury had delivered material that was out of specification per our contract and permit requirements. In June 2017, WE notified the MDEQ, who notified the EPA that the EPA had jurisdiction regarding this matter. We have been working with the EPA to resolve this matter and do not expect it to have a material impact on our financial statements.

03/31/2018 Form 10-Q 51 WEC Energy Group, Inc.

ITEM 1A. RISK FACTORS

There were no material changes from the risk factors presented in our Annual Report on Form 10-K for the year ended December 31, 2017. See Item 1A. Risk Factors in Part I of our 2017 Annual Report on Form 10-K for a discussion of certain risk factors applicable to us.

ITEM 2. UNREGISTERED SALES OF EQUITY SECURITIES AND USE OF PROCEEDS

The following table sets forth information regarding the purchases of our equity securities made by or on behalf of us or any affiliated purchaser (as defined in Exchange Act Rule 10b-18) during the three months ended March 31, 2018:

Issuer Purchases of Equity Securities

2018	Total Number of Shares Purchased	Average Price Paid per Share		Total Number of Shares Purchased as Part of Publicly Announced Plans or Programs	Maximum Approximate Dollar Value of Shares that May Yet Be Purchased Under the Plans or Programs
January 1 – January 31	14,385	$	65.70	—	$	—
February 1 – February 28	5,387	61.61		—	—
March 1 – March 31	—	—		—	—
Total *	19,772	$	64.59	—

* All shares were surrendered by employees to satisfy tax withholding obligations upon vesting of restricted stock.

03/31/2018 Form 10-Q 52 WEC Energy Group, Inc.

ITEM 6. EXHIBITS

Number	Exhibit
10	Material Contracts
	10.1	Letter Agreement by and between WEC Energy Group and Frederick D. Kuester, dated February 23, 2018.
12	Statements re Computation of Ratios
	12.1	Ratio of Earnings to Fixed Charges
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

03/31/2018 Form 10-Q 53 WEC Energy Group, Inc.

SIGNATURE

Pursuant to the requirements 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.

		WEC ENERGY GROUP, INC.
		(Registrant)
		/s/ WILLIAM J. GUC
Date:	May 4, 2018	William J. Guc
		Vice President and Controller
		(Duly Authorized Officer and Chief Accounting Officer)

03/31/2018 Form 10-Q 54 WEC Energy Group, Inc.

EX-10.1

Exhibit 10.1

February 23, 2018

Mr. Fredrick Kuester

[ADDRESS]

[ADDRESS]

Dear Rick:

This letter will confirm compensation and benefits to be provided to you for services as Sr. Executive Vice President of WEC Energy Group, effective March 1, 2018.

Compensation

You will receive a base salary of $765,000 which will be prorated for your 2018 service and will be payable in accordance with the company’s normal payroll practices. In addition to your base pay, you will receive annual incentive compensation with a target value of 80 percent of base pay. You will participate in the Short-Term Performance Plan (STPP), which has pre-established performance measures determined by the Compensation Committee. The STPP will prorate your award based on employment during 2018. You will receive a make-whole amount to ensure you receive annual incentive compensation as if the STPP had applied for the full calendar year. This make-whole amount will be paid at the same time that the STPP award is paid.

You also will participate in the long-term incentive plan with a target compensation level of 275 percent of base pay. Effective with your first day of employment, you will receive an award comprised of 80 percent restricted stock vesting one year from the date of grant and 20 percent stock options vesting in accordance with the standard terms and conditions. Thereafter, you will be eligible for annual awards comprised of the same mix of elements should you remain employed when the next annual grant is awarded to senior executives.

Additional Benefits

You will be eligible to participate in all other benefits available to other senior executives of the company. All benefits described above which are further defined in plan documents are subject to all of the terms in those documents which supersede any other description. Management reserves the right in its discretion to change or terminate all current benefit plans or practices and other policies and procedures. Finally, your employment would be considered at-will; that is, you could be discharged for any reason or no reason at all, at any time and without notice, and likewise, you may resign at any time and without notice.

When this employment offer becomes effective on March 1, 2018, the Consulting Agreement between you and the company, originally dated January 7, 2013, and amended on January 18, 2018, will immediately terminate.

Rick, I look forward to your continued contributions to the success of WEC Energy Group.

Sincerely,

/s/ Gale E. Klappa_________________

Gale E. Klappa

Chairman and Chief Executive Officer

WEC Energy Group, Inc.

__________________

I have reviewed and accept this offer of employment.

Signature: /s/ Frederick D. Kuester            Date: 2/26/2018

EX-12.1

Exhibit 12.1

WEC ENERGY GROUP, INC.

STATEMENT OF COMPUTATION OF RATIO OF EARNINGS TO FIXED CHARGES (Unaudited)	Three Months Ended March 31, 2018			Twelve Months Ended December 31
(in millions, except ratios)				2017			2016			2015			2014			2013
EARNINGS
Pre-tax income *	$	445.6		$	1,587.2		$	1,495.2		$	1,063.5		$	942.6		$	902.4
Add:
Nonutility amortization of capitalized interest	1.8			7.3			7.3			7.3			7.3			7.3
Subtract:
Nonutility capitalized interest	(0.3		)	(1.7		)	(1.0		)	(1.2		)	(0.7		)	(1.7		)
Preferred stock dividends of subsidiary	(0.3		)	(1.4		)	(1.6		)	(2.6		)	(1.6		)	(1.6		)
Earnings before adding fixed charges	446.8			1,591.4			1,499.9			1,067.0			947.6			906.4
FIXED CHARGES
Interest expense	106.7			415.7			402.7			331.4			240.3			250.9
Capitalized interest	1.5			4.9			10.9			8.6			3.0			9.4
Estimated interest component of rentals	1.1			5.7			16.5			19.0			15.9			15.7
Preferred stock dividends of subsidiary	0.3			1.4			1.6			2.6			1.6			1.6
Total fixed charges as defined	109.6			427.7			431.7			361.6			260.8			277.6
Total earnings as defined	$	556.4		$	2,019.1		$	1,931.6		$	1,428.6		$	1,208.4		$	1,184.0
RATIO OF EARNINGS TO FIXED CHARGES	5.1x			4.7x			4.5x			4.0x			4.6x			4.3x

* Pre-tax income consists of income before income taxes less undistributed earnings of equity investees.

EX-31.1

Exhibit 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

I, Gale E. Klappa, certify that:

1. I have reviewed this Quarterly Report on Form 10-Q of WEC Energy Group, Inc.;

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:	May 4, 2018
	/s/ GALE E. KLAPPA
	Gale E. Klappa
	Chairman and Chief Executive Officer
	(Principal Executive Officer)

EX-31.2

Exhibit 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

I, Scott J. Lauber, certify that:

1. I have reviewed this Quarterly Report on Form 10-Q of WEC Energy Group, Inc.;

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:	May 4, 2018
	/s/ SCOTT J. LAUBER
	Scott J. Lauber
	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 Quarterly Report of WEC Energy Group, Inc. (the "Company") on Form 10-Q for the quarter ended March 31, 2018, as filed with the Securities and Exchange Commission on May 4, 2018 (the "Report"), I, Gale E. Klappa, Chairman 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/ GALE E. KLAPPA

Gale E. Klappa

Chairman of the Board and Chief Executive Officer

May 4, 2018

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 Quarterly Report of WEC Energy Group, Inc. (the "Company") on Form 10-Q for the quarter ended March 31, 2018, as filed with the Securities and Exchange Commission on May 4, 2018 (the "Report"), I, Scott J. Lauber, 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/ SCOTT J. LAUBER

Scott J. Lauber

Executive Vice President and Chief Financial Officer

May 4, 2018

XML

DOCUMENT AND ENTITY INFORMATION	3 Months Ended
	Mar. 31, 2018 shares
Document Entity Information [Abstract]
Entity registrant name	WEC Energy Group, Inc.
Entity central index key	0000783325
Current fiscal year end date	--12-31
Entity filer category	Large Accelerated Filer
Document type	10-Q
Document period end date	Mar. 31, 2018
Document fiscal year focus	2018
Document fiscal period focus	Q1
Amendment flag	false
Entity common stock, shares outstanding	315,538,808

XML

CONDENSED CONSOLIDATED INCOME STATEMENTS - USD ($) shares in Millions, $ in Millions	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Income Statement [Abstract]
Operating revenues	$ 2,286.5	$ 2,304.5
Operating expenses
Cost of sales	972.1	941.1
Other operation and maintenance	511.9	504.5
Depreciation and amortization	208.6	194.6
Property and revenue taxes	48.8	49.6
Total operating expenses	1,741.4	1,689.8
Operating income	545.1	614.7
Equity in earnings of transmission affiliates	32.8	41.9
Other income, net	7.5	18.3
Interest expense	106.7	104.7
Other expense	(66.4)	(44.5)
Income before income taxes	478.7	570.2
Income tax expense	88.3	213.3
Net income	390.4	356.9
Preferred stock dividends of subsidiary	0.3	0.3
Net income attributed to common shareholders	$ 390.1	$ 356.6
Earnings per share
Basic (in dollars per share)	$ 1.24	$ 1.13
Diluted (in dollars per share)	$ 1.23	$ 1.12
Weighted average common shares outstanding
Basic (in shares)	315.5	315.6
Diluted (in shares)	316.9	317.2
Dividends per share of common stock (in dollars per share)	$ 0.5525	$ 0.5200

XML

CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Statement of Other Comprehensive Income [Abstract]
Net income	$ 390.4	$ 356.9
Derivatives accounted for as cash flow hedges
Reclassification of gains to net income, net of tax	(0.2)	(0.3)
Defined benefit plans
Amortization of pension and OPEB costs included in net periodic benefit cost, net of tax	1.9	0.1
Other comprehensive income (loss), net of tax	1.7	(0.2)
Comprehensive income	392.1	356.7
Preferred stock dividends of subsidiary	0.3	0.3
Comprehensive income attributed to common shareholders	$ 391.8	$ 356.4

XML

CONDENSED CONSOLIDATED BALANCE SHEETS - USD ($) $ in Millions	Mar. 31, 2018	Dec. 31, 2017
Current assets
Cash and cash equivalents	$ 48.1	$ 38.9
Accounts receivable and unbilled revenues, net of reserves of $160.5 and $143.2, respectively	1,356.8	1,350.7
Materials, supplies, and inventories	376.0	539.0
Prepayments	165.9	210.0
Other	34.0	74.9
Current assets	1,980.8	2,213.5
Long-term assets
Property, plant, and equipment, net of accumulated depreciation of $8,819.8 and $8,618.5, respectively	21,466.3	21,347.0
Regulatory assets	2,929.7	2,803.2
Equity investment in transmission affiliates	1,598.9	1,553.4
Goodwill	3,052.8	3,053.5
Other	757.1	619.9
Long-term assets	29,804.8	29,377.0
Total assets	31,785.6	31,590.5
Current liabilities
Short-term debt	1,200.3	1,444.6
Current portion of long-term debt	957.9	842.1
Accounts payable	592.8	859.9
Accrued payroll and benefits	107.4	169.1
Other	747.5	553.6
Current liabilities	3,605.9	3,869.3
Long-term liabilities
Long-term debt	8,617.5	8,746.6
Deferred income taxes	3,069.9	2,999.8
Deferred revenue, net	538.1	543.3
Regulatory liabilities	3,924.3	3,718.6
Environmental remediation liabilities	617.2	617.4
Pension and OPEB obligations	523.1	397.4
Other	1,191.4	1,206.3
Long-term liabilities	18,481.5	18,229.4
Commitments and contingencies (Note 19)
Common shareholders' equity
Common stock – $0.01 par value; 325,000,000 shares authorized; 315,538,808 and 315,574,624 shares outstanding, respectively	3.2	3.2
Additional paid in capital	4,267.3	4,278.5
Retained earnings	5,392.7	5,176.8
Accumulated other comprehensive income	4.6	2.9
Common shareholders' equity	9,667.8	9,461.4
Preferred stock of subsidiary	30.4	30.4
Total liabilities and equity	$ 31,785.6	$ 31,590.5

XML

CONDENSED CONSOLIDATED BALANCE SHEETS (Parenthetical) - USD ($) $ in Millions	Mar. 31, 2018	Dec. 31, 2017
Statement of Financial Position [Abstract]
Accounts receivable and accrued unbilled revenues, reserves	$ 160.5	$ 143.2
Property, plant, and equipment, accumulated depreciation	$ 8,819.8	$ 8,618.5
Common stock, par value (in dollars per share)	$ 0.01	$ 0.01
Common stock, shares authorized	325,000,000	325,000,000
Common stock, shares outstanding	315,538,808	315,574,624

XML

CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Operating Activities
Net income	$ 390.4	$ 356.9
Reconciliation to cash provided by operating activities
Depreciation and amortization	208.6	194.6
Deferred income taxes and investment tax credits, net	17.0	150.2
Contributions and payments related to pension and OPEB plans	(5.3)	(106.0)
Equity income in transmission affiliates, net of distributions	7.1	(6.7)
Change in -
Accounts receivable and unbilled revenues	(60.1)	55.0
Materials, supplies, and inventories	163.0	170.5
Other current assets	81.3	41.2
Accounts payable	(170.9)	(212.7)
Other current liabilities	128.6	90.8
Other, net	134.3	(19.2)
Net cash provided by operating activities	894.0	714.6
Investing Activities
Capital expenditures	(439.6)	(329.7)
Capital contributions to transmission affiliates	(12.8)	(27.6)
Proceeds from the sale of assets and businesses	0.8	13.1
Proceeds from the sale of investments held in rabbi trust	16.5	8.6
Other, net	(0.7)	2.5
Net cash used in investing activities	(435.8)	(333.1)
Financing Activities
Exercise of stock options	2.1	5.9
Purchase of common stock	(15.8)	(20.2)
Dividends paid on common stock	(174.2)	(164.1)
Retirement of long-term debt	(12.6)	(12.0)
Change in short-term debt	(244.3)	(189.8)
Other, net	(0.3)	(0.6)
Net cash used in financing activities	(445.1)	(380.8)
Net change in cash, cash equivalents, and restricted cash	13.1	0.7
Cash, cash equivalents, and restricted cash at beginning of period	58.6	72.7
Cash, cash equivalents, and restricted cash at end of period	$ 71.7	$ 73.4

XML

GENERAL INFORMATION

3 Months Ended

Mar. 31, 2018

Organization, Consolidation and Presentation of Financial Statements [Abstract]

GENERAL INFORMATION

GENERAL INFORMATION

WEC Energy Group serves approximately 1.6 million electric customers and 2.9 million natural gas customers, and owns approximately 60% of ATC.

As used in these notes, the term "financial statements" refers to the condensed consolidated financial statements. This includes the income statements, statements of comprehensive income, balance sheets, and statements of cash flows, unless otherwise noted. In this report, when we refer to "the Company," "us," "we," "our," or "ours," we are referring to WEC Energy Group and all of its subsidiaries.

We have prepared the unaudited interim financial statements presented in this Form 10-Q pursuant to the rules and regulations of the SEC and GAAP. Accordingly, these financial statements do not include all of the information and footnotes required by GAAP for annual financial statements. These financial statements should be read in conjunction with the consolidated financial statements and footnotes in our Annual Report on Form 10-K for the year ended December 31, 2017. Financial results for an interim period may not give a true indication of results for the year. In particular, the results of operations for the three months ended March 31, 2018, are not necessarily indicative of expected results for 2018 due to seasonal variations and other factors.

In management's opinion, we have included all adjustments, normal and recurring in nature, necessary for a fair presentation of our financial results.

XML

ACQUISITIONS

3 Months Ended

Mar. 31, 2018

Business Combinations [Abstract]

ACQUISITION

ACQUISITIONS

Acquisition of a Wind Energy Generation Facility in Wisconsin

On April 2, 2018, WPS, along with two other unaffiliated utilities, completed the purchase of Forward Wind Energy Center, which consists of 86 wind turbines located in Wisconsin with a total capacity of 129 MW. The aggregate purchase price was $173.9 million of which WPS’s proportionate share was 44.6%, or $77.6 million. Since 2008 and up until the acquisition, WPS purchased 44.6% of the facility’s energy output under a power purchase agreement.

WPS's proportionate share of the facility will be recorded as property, plant, and equipment on the balance sheet and will be included in rate base. Under a joint ownership agreement with the two other utilities, WPS is entitled to its share of generating capability and output of the facility equal to its ownership interest. WPS will also pay its ownership share of additional construction costs and operating expenses.

Acquisition of Natural Gas Storage Facilities in Michigan

On June 30, 2017, we completed the acquisition of Bluewater for $226.0 million. Bluewater owns natural gas storage facilities in Michigan that will provide approximately one-third of the current storage needs for our Wisconsin natural gas utilities. In addition, we incurred $4.9 million of acquisition related costs.

The table below shows the allocation of the purchase price to the assets acquired and liabilities assumed at the date of the acquisition. The excess of the purchase price over the estimated fair values of the assets acquired and liabilities assumed was recognized as goodwill. Bluewater is included in the non-utility energy infrastructure segment. See Note 17, Segment Information, for more information.

(in millions)
Current assets	$	2.0
Net property, plant, and equipment	218.3
Goodwill	6.6
Current liabilities	(0.9		)
Total purchase price	$	226.0

Acquisition of a Wind Energy Generation Facility in Nebraska

On April 30, 2018, we signed an agreement for the acquisition of an 80% membership interest in a 202.5 MW wind generating facility currently under construction known as Upstream Wind Energy Center (“Upstream”) for $276.0 million. Upstream is located in Antelope County, Nebraska and will supply energy to the Southwest Power Pool. The transaction is expected to close in the first quarter of 2019, after Upstream achieves commercial operation. Upstream has entered into an energy swap agreement pursuant to which Upstream will receive a fixed payment in exchange for substantially all of the energy output for a period of ten years. In addition, we anticipate Upstream will qualify for both Federal production tax credits at 100% of the published rate and bonus depreciation.

XML

DISPOSITIONS

3 Months Ended

Mar. 31, 2018

Discontinued Operations and Disposal Groups [Abstract]

DISPOSITION

DISPOSITION

Corporate and Other Segment—Sale of Bostco Real Estate Holdings

In March 2017, we sold the remaining real estate holdings of Bostco located in downtown Milwaukee, Wisconsin, which included retail, office, and residential space. During the first quarter of 2017, we recorded an insignificant gain on the sale, which was included in other income, net on our income statements. The assets included in the sale were not material and, therefore, were not presented as held for sale. The results of operations associated with these assets remained in continuing operations through the sale date as the sale did not represent a shift in our corporate strategy and did not have a major effect on our operations and financial results.

XML

OPERATING REVENUES

3 Months Ended

Mar. 31, 2018

Revenue from Contract with Customer [Abstract]

OPERATING REVENUES

OPERATING REVENUES

Adoption of ASU 2014-09, Revenues from Contracts with Customers

On January 1, 2018, we adopted ASU 2014-09, Revenues from Contracts with Customers, and the related amendments. In accordance with the guidance, revenues are recognized when control of the promised goods or services is transferred to our customers in an amount that reflects the consideration we expect to be entitled to receive in exchange for those goods or services.

We adopted this standard using the modified retrospective method. Results for reporting periods beginning after January 1, 2018, are presented under the new standard. The comparative information has not been restated and continues to be reported under the accounting standards in effect for those periods. Adoption of the standard did not result in an adjustment to our opening retained earnings balance as of January 1, 2018, and we do not expect the adoption of the standard to have a material impact on our net income in future periods.

We adopted the following practical expedients and optional exemptions for the implementation of this standard:

• We elected to exclude from the transaction price any amounts collected from customers for all sales taxes and other similar taxes.

• When applicable, we elected to apply the standard to a portfolio of contracts with similar characteristics, primarily our tariff-based contracts, as we reasonably expect that the effects on the financial statements of applying this guidance to the portfolio would not differ materially from applying this guidance to the individual contracts.

• We elected to recognize revenue in the amount we have the right to invoice for performance obligations satisfied over time when the consideration received from a customer corresponds directly with the value provided to the customer during the same period.

• We elected to not disclose the remaining performance obligations of a contract that has an original expected duration of one year or less.

• We elected to apply this standard only to contracts that are not completed as of the date of initial application.

Disaggregation of Operating Revenues

The following tables present our operating revenues disaggregated by revenue source. Comparable amounts have not been presented for the three months ended March 31, 2017, due to our adoption of this standard under the modified retrospective method.

(in millions)	Wisconsin		Illinois			Other States			Total Utility Operations			Electric Transmission		Non-Utility Energy Infrastructure		Corporate and Other		Reconciling Eliminations			WEC Energy Group Consolidated
Three Months Ended March 31, 2018
Electric	$	1,067.7	$	—		$	—		$	1,067.7		$	—	$	—	$	—	$	—		$	1,067.7
Natural gas	518.0		507.6			172.7			1,198.3			—		14.9		—		(2.5		)	1,210.7
Total utility revenues	1,585.7		507.6			172.7			2,266.0			—		14.9		—		(2.5		)	2,278.4
Other non-utility revenues	—		—			3.9			3.9			—		7.1		1.3		(0.7		)	11.6
Total revenues from contracts with customers	1,585.7		507.6			176.6			2,269.9			—		22.0		1.3		(3.2		)	2,290.0
Other operating revenues	3.4		(0.3		)	(6.7		)	(3.6		)	—		96.1		0.1		(96.1		)	(3.5		)
Total operating revenues	$	1,589.1	$	507.3		$	169.9		$	2,266.3		$	—	$	118.1	$	1.4	$	(99.3	)	$	2,286.5

Revenues from Contracts with Customers

Electric Utility Operating Revenues

The following table disaggregates electric utility operating revenues into customer class for the current period:

(in millions)	Electric Utility Operating Revenues
Three Months Ended March 31, 2018
Residential	$	384.3
Small commercial and industrial	330.7
Large commercial and industrial	203.9
Other	7.7
Total retail revenues	926.6
Wholesale	54.9
Resale	73.8
Steam	9.7
Other utility revenues	2.7
Total electric utility operating revenues	$	1,067.7

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 Wisconsin residential and commercial and industrial customers and the majority of our Michigan residential and commercial and industrial customers, our performance obligation is bundled and consists of both the sale and the delivery of the electric commodity. In our Michigan service territory, a limited number of residential and commercial and industrial customers can purchase the commodity from a third party. In this case, the delivery of the electricity represents our sole performance obligation. The rates, charges, terms, and conditions of service for sales to these customers are included in tariffs that have been approved by state regulators. These rates often have a fixed component customer charge and a usage-based variable component. 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 using an output method based on the quantity of electricity delivered each month.

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 our utilities provide generation to match the customer's load, similar to requirements contracts, or they can purchase specified quantities of electricity and capacity. The rates, charges, terms and conditions of service for sales to wholesale customers are included in tariffs that have been approved by the FERC. 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 utilities 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.

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. 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. 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.

Natural Gas Utility Operating Revenues

The following table disaggregates natural gas utility operating revenues into customer class for the current period:

(in millions)	Wisconsin			Illinois			Other States			Total Natural Gas Utility Operations
Three Months Ended March 31, 2018
Residential	$	356.7		$	332.6		$	123.2		$	812.5
Commercial and industrial	187.9			109.4			64.7			362.0
Total retail revenues	544.6			442.0			187.9			1,174.5
Transport	21.0			77.7			9.9			108.6
Other utility revenues *	(47.6		)	(12.1		)	(25.1		)	(84.8		)
Total natural gas utility operating revenues	$	518.0		$	507.6		$	172.7		$	1,198.3

* Includes amounts (refunded to) collected from customers for purchased gas adjustment costs.

We recognize natural gas utility operating revenues under requirements contracts with residential, commercial and industrial, and transportation customers served under the tariffs of our regulated utilities. 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 certain of our service territories, 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 is valued using rates in the tariffs of our regulated utilities, which have been approved by state regulators. These rates often have a fixed component customer charge and a usage-based variable component. 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 using an output method based on natural gas delivered each month.

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 Non-Utility Operating Revenues

Other non-utility operating revenues consist primarily of the following:

(in millions)	Three Months Ended March 31, 2018
We Power revenues	$	6.4
Appliance service revenues	3.9
Distributed renewable solar project revenues	1.3
Total other non-utility operating revenues	$	11.6

As part of the construction of the We Power electric generating units, we capitalized interest during construction, which is included in property, plant, and equipment. As allowed by the PSCW, we collected these carrying costs from WE's utility customers during construction. The equity portion of these carrying costs was recorded as deferred revenue, and we continually amortize the deferred carrying costs to revenues over the life of the plants to better match the costs of owning the plant while we are providing service to our customers. During the three months ended March 31, 2018, we recorded $6.4 million of revenue related to these deferred carrying costs, which were included in the contract liability balance at the beginning of the period. This contract liability is presented as deferred revenue, net on our balance sheets.

Non-utility operating revenues are derived primarily from servicing appliances for customers at MERC. These contracts customarily have a duration of one year or less and consist of a single performance obligation satisfied over time. We use a time-based output method to recognize revenues monthly for the service fee.

Revenues from distributed renewable solar projects consist primarily of sales of renewable energy and solar renewable energy certificates (SRECs) generated by WPS Power Development, LLC. The sale of SRECs is a distinct performance obligation as they are often sold separately from the renewable energy generated. Although the performance obligation for the sale of renewable energy is recognized over time and the performance obligation for SRECs is recognized at a point-in-time, the timing of revenue recognition is the same and occurs as renewable energy is generated.

Other Operating Revenues

Other operating revenues consist primarily of the following:

(in millions)	Three Months Ended March 31, 2018
Alternative revenues *	$	(16.1	)
Late payment charges	11.4
Leases	1.2
Total other operating revenues	$	(3.5	)

* Negative amounts can result from alternative revenues being reversed to revenues from contracts with customers as the customer is billed for these alternative revenues. Negative amounts can also result from revenues to be refunded to customers subject to decoupling mechanisms and wholesale true-ups, as discussed below.

Alternative Revenues

Alternative revenues are created from programs authorized by regulators that allow our utilities 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. Alternative revenue programs allow compensation for the effects of weather abnormalities, other external factors, or demand side management initiatives. Alternative revenue programs can also provide incentive awards if the utility achieves certain objectives and in other limited circumstances. 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.

Below is a summary of the alternative revenue programs at our utilities:

• The rates of PGL, NSG, and MERC include decoupling mechanisms. These mechanisms differ by state and allow the utilities to recover or refund the differences between actual and authorized margins for certain customers.

• MERC’s rates include a conservation improvement program rider, which includes a financial incentive for meeting energy savings goals.

• WE and WPS provide wholesale electric service 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 or refund to the customer. We consider the true-up portion of the wholesale electric revenues to be alternative revenues.

XML

PROPERTY, PLANT, AND EQUIPMENT

3 Months Ended

Mar. 31, 2018

Property, Plant and Equipment [Abstract]

PROPERTY, PLANT, AND EQUIPMENT

PROPERTY, PLANT, AND EQUIPMENT

Wisconsin Segment Plant to be Retired

We have evaluated future plans for our older and less efficient fossil fuel generating units and have announced the retirement of the plants identified below. The net book value of these plants was classified as plant to be retired within property, plant, and equipment on our balance sheet at March 31, 2018. In addition, severance expense in the amount of $29.4 million was recorded within the Wisconsin segment in 2017 related to these announced plant retirements.

Pleasant Prairie Power Plant

As a result of a MISO ruling in December 2017, the Pleasant Prairie power plant was retired effective April 10, 2018. Retirement of the Pleasant Prairie power plant was considered probable at March 31, 2018. The net book value of this generating unit was $674.1 million at March 31, 2018, and was classified as plant to be retired within property, plant, and equipment on our balance sheet. This unit is included in rate base, and WE continues to depreciate it on a straight-line basis using the composite depreciation rates approved by the PSCW. The physical dismantlement of the plant will not occur immediately. It may take several years to finalize long-term plans for the site. See Note 19, Commitments and Contingencies, for more information.

Presque Isle Power Plant

In October 2017, the MPSC approved UMERC’s application to construct and operate approximately 180 MW of natural gas-fired generation in the Upper Peninsula of Michigan. The new units are expected to begin commercial operation by mid-2019. Upon receiving the MPSC's approval, retirement of the PIPP generating units became probable. As a result of a MISO ruling received in April 2018, the PIPP units must be retired no later than May 31, 2019. The net book value of these units was $188.7 million at March 31, 2018, and 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 continues to depreciate them on a straight-line basis using the composite depreciation rates approved by the PSCW. See Note 19, Commitments and Contingencies, and Note 21, Regulatory Environment, for more information.

Pulliam Power Plant

WPS anticipates retiring Pulliam generating units 7 and 8 near the end of 2018 when certain transmission lines are completed. Retirement of the Pulliam generating units was probable at March 31, 2018. The net book value of these generating units was $43.6 million at March 31, 2018, and was classified as plant to be retired within property, plant, and equipment on our balance sheet. These units are included in rate base, and WPS continues to depreciate them on a straight-line basis using the composite depreciation rates approved by the PSCW. See Note 19, Commitments and Contingencies, for more information.

Edgewater Unit 4

As a result of the continued implementation of the Consent Decree related to the jointly owned Columbia and Edgewater plants, retirement of the Edgewater 4 generating unit was probable at March 31, 2018. The plant must be retired by September 30, 2018. The net book value of WPS's ownership share of this generating unit was $12.7 million at March 31, 2018, and was classified as plant to be retired within property, plant, and equipment on our balance sheet. This unit is included in rate base, and WPS continues to depreciate it on a straight-line basis using the composite depreciation rates approved by the PSCW. See Note 19, Commitments and Contingencies, for more information regarding the Consent Decree.

XML

COMMON EQUITY

3 Months Ended

Mar. 31, 2018

Equity [Abstract]

COMMON EQUITY

COMMON EQUITY

Stock-Based Compensation

During the first quarter of 2018, the Compensation Committee of our Board of Directors awarded the following stock-based compensation awards to our directors, officers, and certain other key employees:

Award Type	Number of Awards
Stock options (1)	710,710
Restricted shares (2)	156,340
Performance units	217,560

⁽¹⁾  Stock options awarded had a weighted-average exercise price of $65.60 and a weighted-average grant date fair value of $7.71 per option.

⁽²⁾  Restricted shares awarded had a weighted-average grant date fair value of $64.20 per share.

Restrictions

Our ability as a holding company to pay common stock dividends primarily depends on the availability of funds received from our utility subsidiaries and our non-utility subsidiary, We Power. Various financing arrangements and regulatory requirements impose certain restrictions on the ability of our subsidiaries to transfer funds to us in the form of cash dividends, loans, or advances. All of our utility subsidiaries, with the exception of UMERC and MGU, are prohibited from loaning funds to us, either directly or indirectly.

See Note 9, Common Equity, in our 2017 Annual Report on Form 10-K for additional information on these and other restrictions.

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

Common Stock Dividends

On April 19, 2018, our Board of Directors declared a quarterly cash dividend of $0.5525 per share, payable on June 1, 2018, to shareholders of record on May 14, 2018.

XML

SHORT-TERM DEBT AND LINES OF CREDIT

3 Months Ended

Mar. 31, 2018

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:

(in millions, except percentages)	March 31, 2018			December 31, 2017
Commercial paper
Amount outstanding	$	1,200.3		$	1,444.6
Weighted-average interest rate on amounts outstanding	2.24		%	1.77		%

Our average amount of commercial paper borrowings based on daily outstanding balances during the three months ended March 31, 2018, was $1,254.4 million with a weighted-average interest rate during the period of 1.90%.

The information in the table below relates to our revolving credit facilities used to support our commercial paper borrowing programs, including available capacity under these facilities:

(in millions)	Maturity	March 31, 2018
WEC Energy Group	October 2022	$	1,200.0
WE	October 2022	500.0
WPS	October 2022	400.0
WG	October 2022	350.0
PGL	October 2022	350.0
Total short-term credit capacity		$	2,800.0
Less:
Letters of credit issued inside credit facilities		$	1.2
Commercial paper outstanding		1,200.3
Available capacity under existing agreements		$	1,598.5

XML

LONG TERM DEBT

3 Months Ended

Mar. 31, 2018

Long-term Debt, Unclassified [Abstract]

Long Term Debt

LONG-TERM DEBT

Integrys Holding, Inc.

In April 2018, Integrys issued a notice to redeem at par all $114.9 million outstanding of its 2006 Junior Subordinated Notes due December 1, 2066. The redemption will be effective May 14, 2018. As a result, the $114.9 million outstanding balance was included in the current portion of long-term debt on our balance sheet at March 31, 2018.

XML

MATERIALS, SUPPLIES, AND INVENTORIES

3 Months Ended

Mar. 31, 2018

Inventory Disclosure [Abstract]

MATERIALS, SUPPLIES, AND INVENTORIES

MATERIALS, SUPPLIES, AND INVENTORIES

Our inventory consisted of:

(in millions)	March 31, 2018		December 31, 2017
Natural gas in storage	$	34.8	$	209.0
Materials and supplies	213.7		211.2
Fossil fuel	127.5		118.8
Total	$	376.0	$	539.0

PGL and NSG price natural gas storage injections at the calendar year average of the costs of natural gas supply purchased. Withdrawals from storage are priced on the LIFO cost method. For interim periods, the difference between current projected replacement cost and the LIFO cost for quantities of natural gas temporarily withdrawn from storage is recorded as a temporary LIFO liquidation debit or credit. At March 31, 2018, we had a temporary LIFO liquidation credit of $35.6 million recorded within other current liabilities on our balance sheet. Due to seasonality requirements, PGL and NSG expect these interim reductions in LIFO layers to be replenished by year end.

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

XML

INCOME TAXES

3 Months Ended

Mar. 31, 2018

Income Tax Disclosure [Abstract]

INCOME TAXES

INCOME TAXES

The provision for income taxes for the quarter ended March 31, 2018, 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:

	Amount			Effective Tax Rate
Statutory federal income tax	$	100.5		21.0	%
State income taxes net of federal tax benefit	29.9			6.2	%
Federal tax reform	(15.5		)	(3.2	)%
Tax repairs	(25.5		)	(5.3	)%
Other	(1.1		)	(0.3	)%
Total income tax expense	$	88.3		18.4	%

The effective tax rate of 18.4% for the first quarter of 2018 differs from the United States statutory federal income tax rate of 21% primarily due to the impact of the Tax Legislation and the flow through of tax repairs in connection with the Wisconsin rate settlement, partially offset by state income taxes. The Tax Legislation, signed into law in December 2017, required our regulated utilities to remeasure their deferred income taxes and begin to amortize the resulting excess deferred income taxes beginning in 2018 in accordance with normalization requirements (see Federal tax reform line above). See Note 21, Regulatory Environment, for more information about the impact of the Tax Legislation and the Wisconsin rate settlement.

On December 22, 2017, the SEC staff issued guidance in Staff Accounting Bulletin 118 (SAB 118), Income Tax Accounting Implications of the Tax Cuts and Jobs Act, which provides for a measurement period of up to one year from the enactment date to complete accounting under GAAP for the tax effects of the legislation. Due to the complex and comprehensive nature of the enacted tax law changes, and their application under GAAP, certain amounts related to bonus depreciation and future tax benefit utilization recorded in the financial statements as a result of the Tax Legislation are to be considered "provisional" as discussed in SAB 118 and subject to revision. We are awaiting additional guidance from industry and income tax authorities in order to finalize our accounting.

XML

FAIR VALUE MEASUREMENTS

3 Months Ended

Mar. 31, 2018

Fair Value Disclosures [Abstract]

FAIR VALUE MEASUREMENTS

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 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 financial 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 are categorized in Level 3 due to the significance of unobservable or internally-developed inputs.

We recognize transfers between levels of the fair value hierarchy at their value as of the end of the reporting period.

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:

	March 31, 2018
(in millions)	Level 1		Level 2		Level 3		Total
Derivative assets
Natural gas contracts	$	1.7	$	0.5	$	—	$	2.2
Petroleum products contracts	0.6		—		—		0.6
FTRs	—		—		1.5		1.5
Coal contracts	—		1.1		—		1.1
Total derivative assets	$	2.3	$	1.6	$	1.5	$	5.4
Investments held in rabbi trust	$	103.6	$	—	$	—	$	103.6
Derivative liabilities
Natural gas contracts	$	3.4	$	1.4	$	—	$	4.8
Coal contracts	—		0.3		—		0.3
Total derivative liabilities	$	3.4	$	1.7	$	—	$	5.1

	December 31, 2017
(in millions)	Level 1		Level 2		Level 3		Total
Derivative assets
Natural gas contracts	$	1.8	$	3.9	$	—	$	5.7
Petroleum products contracts	1.2		—		—		1.2
FTRs	—		—		4.4		4.4
Coal contracts	—		1.1		—		1.1
Total derivative assets	$	3.0	$	5.0	$	4.4	$	12.4
Investments held in rabbi trust	$	120.7	$	—	$	—	$	120.7
Derivative liabilities
Natural gas contracts	$	7.0	$	3.8	$	—	$	10.8
Coal contracts	—		0.8		—		0.8
Total derivative liabilities	$	7.0	$	4.6	$	—	$	11.6

The derivative assets and liabilities listed in the tables above include options, swaps, 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.

We hold investments in the Integrys rabbi trust. These investments are restricted as they can only be withdrawn from the trust to fund participants' benefits under the Integrys deferred compensation plan and certain Integrys non-qualified pension plans. As we do not intend to sell the investments in the near term, they are included in other long-term assets on our balance sheets. For the three months ended March 31, 2018 and 2017, the net unrealized (losses) and gains included in earnings related to the investments held at the end of the period were $(3.1) million and $5.2 million, respectively.

The following table summarizes the changes to derivatives classified as Level 3 in the fair value hierarchy:

	Three Months Ended March 31
(in millions)	2018			2017
Balance at the beginning of the period	$	4.4		$	5.1
Settlements	(2.9		)	(3.4		)
Balance at the end of the period	$	1.5		$	1.7

Fair Value of Financial Instruments

The following table shows the financial instruments included on our balance sheets that are not recorded at fair value:

	March 31, 2018				December 31, 2017
(in millions)	Carrying Amount		Fair Value		Carrying Amount		Fair Value
Preferred stock	$	30.4	$	29.1	$	30.4	$	30.5
Long-term debt, including current portion *	9,549.3		10,054.5		9,561.7		10,341.9

* The carrying amount of long-term debt excludes capital lease obligations of $26.1 million and $27.0 million at March 31, 2018 and December 31, 2017, respectively.

The fair values of our long-term debt and preferred stock are categorized within Level 2 of the fair value hierarchy.

XML

DERIVATIVE INSTRUMENTS

3 Months Ended

Mar. 31, 2018

Derivative Instruments and Hedging Activities Disclosure [Abstract]

DERIVATIVE INSTRUMENTS

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 and shareholders. Our approach is non-speculative and designed to mitigate risk. Regulated hedging programs are approved by our state regulators.

We record derivative instruments on our balance sheets as an asset or liability 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, our regulators allow the effects of fair value accounting to be offset to regulatory assets and liabilities.

The following table shows our derivative assets and derivative liabilities:

	March 31, 2018				December 31, 2017
(in millions)	Derivative Assets		Derivative Liabilities		Derivative Assets		Derivative Liabilities
Other current
Natural gas contracts	$	2.2	$	3.7	$	5.6	$	9.4
Petroleum products contracts	0.6		—		1.2		—
FTRs	1.5		—		4.4		—
Coal contracts	0.8		0.3		0.6		0.6
Total other current *	$	5.1	$	4.0	$	11.8	$	10.0
Other long-term
Natural gas contracts	$	—	$	1.1	$	0.1	$	1.4
Coal contracts	0.3		—		0.5		0.2
Total other long-term *	$	0.3	$	1.1	$	0.6	$	1.6
Total	$	5.4	$	5.1	$	12.4	$	11.6

* On our balance sheets, we classify derivative assets and liabilities as other current or other long-term based on the maturities of the underlying contracts.

Realized gains (losses) on derivative instruments are primarily recorded in cost of sales on the income statements. Our estimated notional sales volumes and realized gains (losses) were as follows:

	Three Months Ended March 31, 2018				Three Months Ended March 31, 2017
(in millions)	Volumes	Gains (Losses)			Volumes	Gains (Losses)
Natural gas contracts	48.1 Dth	$	(5.2	)	34.1 Dth	$	(0.3	)
Petroleum products contracts	2.1 gallons	0.5			4.9 gallons	(0.5		)
FTRs	8.2 MWh	3.7			9.2 MWh	3.0
Total		$	(1.0	)		$	2.2

On our balance sheets, the amounts recognized for the right to reclaim cash collateral or the obligation to return cash collateral are not offset against the fair value amounts recognized for derivative instruments executed with the same counterparty under the same master netting arrangement. At March 31, 2018 and December 31, 2017, we had posted cash collateral of $11.8 million and $16.2 million, respectively, in our margin accounts. These amounts were recorded on our balance sheets in other current assets.

The following table shows derivative assets and derivative liabilities if derivative instruments by counterparty were presented net on our balance sheets:

	March 31, 2018							December 31, 2017
(in millions)	Derivative Assets			Derivative Liabilities				Derivative Assets			Derivative Liabilities
Gross amount recognized on the balance sheet	$	5.4		$	5.1			$	12.4		$	11.6
Gross amount not offset on the balance sheet	(2.1		)	(3.7		)	(1)	(4.9		)	(9.0		)	(2)
Net amount	$	3.3		$	1.4			$	7.5		$	2.6

⁽¹⁾   Includes cash collateral posted of $1.6 million.

⁽²⁾  Includes cash collateral posted of $4.1 million.

Certain of our derivative and nonderivative commodity instruments contain provisions that could require "adequate assurance" in the event of a material change in our creditworthiness, or the posting of additional collateral for instruments in net liability positions, if triggered by a decrease in credit ratings. The aggregate fair value of all derivative instruments with specific credit risk-related contingent features that were in a net liability position was $1.1 million and $3.7 million at March 31, 2018 and December 31, 2017, respectively. At March 31, 2018 and December 31, 2017, we had not posted any collateral related to the credit risk-related contingent features of these commodity instruments. If all of the credit risk-related contingent features contained in derivative instruments in a net liability position had been triggered at March 31, 2018 and December 31, 2017, we would have been required to post collateral of $1.5 million and $2.7 million, respectively.

XML

GUARANTEES

3 Months Ended

Mar. 31, 2018

Guarantees [Abstract]

GUARANTEES

GUARANTEES

The following table shows our outstanding guarantees:

			Expiration
(in millions)	Total Amounts Committed at March 31, 2018		Less Than 1 Year		1 to 3 Years		Over 3 Years
Guarantees
Guarantees supporting commodity transactions of subsidiaries (1)	$	8.1	$	8.1	$	—	$	—
Standby letters of credit (2)	71.4		46.0		25.4		—
Surety bonds (3)	9.8		9.7		0.1		—
Other guarantees (4)	11.1		0.5		—		10.6
Total guarantees	$	100.4	$	64.3	$	25.5	$	10.6

⁽¹⁾  Consists of $8.1 million to support the business operations of Bluewater.

⁽²⁾  At our request or the request of our subsidiaries, financial institutions have issued standby letters of credit for the benefit of third parties that have extended credit to our subsidiaries. These amounts are not reflected on our balance sheets.

⁽³⁾  Primarily for workers compensation self-insurance programs and obtaining various licenses, permits, and rights-of-way. These amounts are not reflected on our balance sheets.

⁽⁴⁾  Consists of $11.1 million related to other indemnifications, for which a liability of $10.6 million related to workers compensation coverage was recorded on our balance sheets.

XML

EMPLOYEE BENEFITS

3 Months Ended

Mar. 31, 2018

Retirement Benefits [Abstract]

EMPLOYEE BENEFITS

EMPLOYEE BENEFITS

The following tables show the components of net periodic pension and OPEB costs for our benefit plans.

	Pension Costs
	Three Months Ended March 31
(in millions)	2018			2017
Service cost	$	12.0		$	11.7
Interest cost	28.3			31.2
Expected return on plan assets	(49.6		)	(49.6		)
Loss on plan settlement	0.4			—
Amortization of prior service cost	0.7			0.7
Amortization of net actuarial loss	23.1			21.9
Net periodic benefit cost	$	14.9		$	15.9

	OPEB Costs
	Three Months Ended March 31
(in millions)	2018			2017
Service cost	$	6.2		$	6.3
Interest cost	7.5			8.5
Expected return on plan assets	(14.9		)	(13.7		)
Amortization of prior service credit	(3.8		)	(2.8		)
Amortization of net actuarial loss	0.3			1.5
Net periodic benefit credit	$	(4.7	)	$	(0.2	)

During the three months ended March 31, 2018, we made contributions and payments of $3.7 million related to our pension plans and $1.6 million related to our OPEB plans. We expect to make contributions and payments of $8.5 million related to our pension plans and $7.9 million related to our OPEB plans during the remainder of 2018, dependent upon various factors affecting us, including our liquidity position and the effects of the new Tax Legislation.

Effective January 1, 2018, we adopted ASU 2017-07, Improving the Presentation of Net Periodic Pension Cost and Net Periodic Postretirement Benefit Cost, which modifies certain aspects of the accounting for employee benefit costs. Under the new guidance, only the service cost component can be included in total operating expenses. The remaining components of net periodic benefit cost are required to be presented in the income statement separately from the service cost component, outside of operating income. As required, this change was applied retrospectively to all prior periods presented. Accordingly, for the quarters ended March 31, 2018 and 2017, we have presented the service cost component of our retirement benefit plans in other operation and maintenance on the income statements, while presenting the non-service cost components in other income, net. For the quarters ended March 31, 2018 and 2017, the non-service cost components of net benefit cost were in a net credit position, in the amount of $(7.2) million and $(2.6) million, respectively. The $(2.6) million related to the first quarter of 2017 was reclassified from other operation and maintenance to other income, net on our income statements.

As required by ASU 2017-07, our income statements for the years ended December 31, 2017, 2016, and 2015 were retroactively restated from what was previously presented in our 2017 Annual Report on Form 10-K. The impacts to our income statements from adoption of this standard are reflected in the table below.

	Year Ended December 31, 2017						Year Ended December 31, 2016							Year Ended December 31, 2015
(in millions)	Form 10-K Income Statement		Impact of ASU 2017-07		Income Statement After Adoption		Form 10-K Income Statement		Impact of ASU 2017-07			Income Statement After Adoption		Form 10-K Income Statement		Impact of ASU 2017-07		Income Statement After Adoption
Operating expenses
Other operation and maintenance	$	2,047.0	$	9.1	$	2,056.1	$	2,185.5	$	(14.2	)	$	2,171.3	$	1,709.3	$	1.4	$	1,710.7
Other expense
Other income, net	64.6		9.1		73.7		80.8		(14.2		)	66.6		58.9		1.4		60.3

In addition, under ASU 2017-07, only the service cost component of net periodic benefit cost is eligible for capitalization to property, plant, and equipment. In prior periods, a portion of all net benefit cost components was capitalized to property, plant, and equipment. As required, this amendment was applied prospectively, beginning January 1, 2018. As a result of the application of accounting principles for rate regulated entities, the non-service cost components of the net benefit cost that are no longer eligible for capitalization under this standard, but are capitalized under the regulatory framework, will be presented as regulatory assets or liabilities rather than property, plant, and equipment.

XML

GOODWILL

3 Months Ended

Mar. 31, 2018

Goodwill and Intangible Assets Disclosure [Abstract]

GOODWILL

GOODWILL

Goodwill represents the excess of the cost of an acquisition over the fair value of the identifiable net assets acquired. The following table shows changes to our goodwill balances by segment during the three months ended March 31, 2018:

(in millions)	Wisconsin		Illinois		Other States		Non-Utility Energy Infrastructure			Total
Goodwill balance as of January 1, 2018	$	2,104.3	$	758.7	$	183.2	$	7.3		$	3,053.5
Adjustment to Bluewater purchase price allocation (1)	—		—		—		(0.7		)	(0.7		)
Goodwill balance as of March 31, 2018 (2)	$	2,104.3	$	758.7	$	183.2	$	6.6		$	3,052.8

⁽¹⁾  See Note 2, Acquisitions, for more information on the acquisition of Bluewater.

⁽²⁾  We had no accumulated impairment losses related to our goodwill as of March 31, 2018.

XML

INVESTMENT IN TRANSMISSION AFFILIATES

3 Months Ended

Mar. 31, 2018

Equity Method Investments and Joint Ventures [Abstract]

INVESTMENT IN TRANSMISSION AFFILIATES

INVESTMENT IN TRANSMISSION AFFILIATES

We own approximately 60% of ATC, a for-profit, transmission-only company regulated by the FERC for cost of service and certain state regulatory commissions for routing and siting of transmission projects. We also own approximately 75% of ATC Holdco, a separate entity formed in December 2016 to invest in transmission-related projects outside of ATC's traditional footprint. The following tables provide a reconciliation of the changes in our investments in ATC and ATC Holdco:

	Three Months Ended March 31, 2018
(in millions)	ATC		ATC Holdco			Total
Balance at beginning of period *	$	1,515.8	$	37.6		$	1,553.4
Add: Earnings (loss) from equity method investment	33.4		(0.6		)	32.8
Add: Capital contributions	12.0		0.8			12.8
Less: Other	0.1		—			0.1
Balance at end of period	$	1,561.1	$	37.8		$	1,598.9

* Distributions of $39.9 million, received in the first quarter of 2018, were approved and recorded as a receivable from ATC in other current assets at December 31, 2017.

	Three Months Ended March 31, 2017
(in millions)	ATC		ATC Holdco			Total
Balance at beginning of period *	$	1,443.9	$	—		$	1,443.9
Add: Earnings (loss) from equity method investment	47.7		(5.8		)	41.9
Add: Capital contributions	24.1		3.5			27.6
Less: Other	0.1		—			0.1
Balance at end of period	$	1,515.6	$	(2.3	)	$	1,513.3

* Distributions of $35.2 million, received in the first quarter of 2017, were approved and recorded as a receivable from ATC in other current assets at December 31, 2016.

We pay ATC for network 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. We are required to pay the cost of needed transmission infrastructure upgrades for new generation projects while the projects are under construction. ATC reimburses us for these costs when the new generation is placed in service.

The following table summarizes our significant related party transactions with ATC:

	Three Months Ended March 31
(in millions)	2018		2017
Charges to ATC for services and construction	$	4.6	$	4.2
Charges from ATC for network transmission services	84.5		87.3
Refund from ATC per FERC ROE order	—		28.3

Our balance sheets included the following receivables and payables related to ATC:

(in millions)	March 31, 2018		December 31, 2017
Accounts receivable
Services provided to ATC	$	1.8	$	1.5
Other current assets
Dividends receivable from ATC	—		39.9
Accounts payable
Services received from ATC	24.0		31.2

Summarized financial data for ATC is included in the following tables:

	Three Months Ended March 31
(in millions)	2018		2017
Income statement data
Operating revenues	$	165.4	$	174.7
Operating expenses	84.9		82.7
Other expense, net	27.6		26.1
Net income	$	52.9	$	65.9

(in millions)	March 31, 2018		December 31, 2017
Balance sheet data
Current assets	$	84.7	$	87.7
Noncurrent assets	4,681.7		4,598.9
Total assets	$	4,766.4	$	4,686.6
Current liabilities	$	473.3	$	767.2
Long-term debt	2,065.3		1,790.6
Other noncurrent liabilities	266.4		240.3
Shareholders' equity	1,961.4		1,888.5
Total liabilities and shareholders' equity	$	4,766.4	$	4,686.6

XML

SEGMENT INFORMATION

3 Months Ended

Mar. 31, 2018

Segment Reporting [Abstract]

SEGMENT INFORMATION

SEGMENT INFORMATION

At March 31, 2018, we reported six segments, which are described below.

• The Wisconsin segment includes the electric and natural gas utility operations of WE, WG, WPS, and UMERC.

• The Illinois segment includes the natural gas utility and non-utility operations of PGL and NSG.

• The other states segment includes the natural gas utility and non-utility operations of MERC and MGU.

• The electric transmission segment includes our approximate 60% ownership interest in ATC, a for-profit, transmission-only company regulated by the FERC for cost of service and certain state regulatory commissions for routing and siting of transmission projects, and our approximate 75% ownership interest in ATC Holdco, which invests in transmission-related projects outside of ATC's traditional footprint.

• The non-utility energy infrastructure segment includes We Power, which owns and leases generating facilities to WE, and Bluewater, which owns underground natural gas storage facilities in Michigan.

• The corporate and other segment includes the operations of the WEC Energy Group holding company, the Integrys holding company, the Peoples Energy, LLC holding company, Wispark LLC, Bostco, Wisvest LLC, Wisconsin Energy Capital Corporation, WBS, and WPS Power Development LLC. In the first quarter of 2017, we sold substantially all of the remaining assets of Bostco. See Note 3, Disposition, for more information on this sale.

All of our operations are located within the United States. The following tables show summarized financial information related to our reportable segments for the three months ended March 31, 2018 and 2017:

	Utility Operations
(in millions)	Wisconsin		Illinois		Other States		Total Utility Operations		Electric Transmission		Non-Utility Energy Infrastructure		Corporate and Other			Reconciling Eliminations			WEC Energy Group Consolidated
Three Months Ended
March 31, 2018
External revenues	$	1,589.1	$	507.3	$	169.9	$	2,266.3	$	—	$	18.8	$	1.4		$	—		$	2,286.5
Intersegment revenues	—		—		—		—		—		99.3		—			(99.3		)	—
Other operation and maintenance	468.5		112.2		26.6		607.3		—		1.7		(0.3		)	(96.8		)	511.9
Depreciation and amortization	135.1		40.9		6.6		182.6		—		18.3		7.7			—			208.6
Operating income (loss)	273.7		147.6		36.2		457.5		—		93.0		(5.4		)	—			545.1
Equity in earnings of transmission affiliates	—		—		—		—		32.8		—		—			—			32.8
Interest expense	49.4		12.3		2.1		63.8		—		16.1		28.0			(1.2		)	106.7

	Utility Operations
(in millions)	Wisconsin		Illinois		Other States		Total Utility Operations		Electric Transmission		Non-Utility Energy Infrastructure		Corporate and Other			Reconciling Eliminations			WEC Energy Group Consolidated
Three Months Ended
March 31, 2017
External revenues	$	1,612.1	$	525.3	$	157.9	$	2,295.3	$	—	$	6.3	$	2.9		$	—		$	2,304.5
Intersegment revenues	—		—		—		—		—		109.0		—			(109.0		)	—
Other operation and maintenance *	465.7		119.6		28.2		613.5		—		0.4		(0.4		)	(109.0		)	504.5
Depreciation and amortization	129.3		36.2		6.0		171.5		—		17.5		5.6			—			194.6
Operating income (loss) *	329.5		156.7		33.5		519.7		—		97.4		(2.4		)	—			614.7
Equity in earnings of transmission affiliates	—		—		—		—		41.9		—		—			—			41.9
Interest expense	48.7		11.1		2.3		62.1		—		15.3		29.1			(1.8		)	104.7

* Includes the retroactive restatement impacts of the implementation of ASU 2017-07. See Note 14, Employee Benefits, for more information on this new standard.

XML

VARIABLE INTEREST ENTITIES

3 Months Ended

Mar. 31, 2018

Variable Interest Entity, Reporting Entity Involvement, Maximum Loss Exposure, Determination Methodology and Factors [Abstract]

VARIABLE INTEREST ENTITIES

VARIABLE INTEREST ENTITIES

The primary beneficiary of a variable interest entity must consolidate the entity's assets and liabilities. In addition, certain disclosures are required for significant interest holders in variable interest entities.

We assess our relationships with potential variable interest entities, such as our coal suppliers, natural gas suppliers, coal transporters, natural gas transporters, and other counterparties related to power purchase agreements, 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.

Investment in Transmission Affiliates

We own approximately 60% of ATC, a for-profit, electric transmission company regulated by the FERC and certain state regulatory commissions. We have determined that ATC is a variable interest entity but that consolidation is not required since we are not ATC's primary beneficiary. As a result of our limited voting rights, we do not have the power to direct the activities that most significantly impact ATC's economic performance. We account for ATC as an equity method investment. The significant assets and liabilities related to ATC recorded on our balance sheets were our equity investment, distributions receivable, and accounts payable. At March 31, 2018 and December 31, 2017, our equity investment was $1,561.1 million and $1,515.8 million, respectively, which approximates our maximum exposure to loss as a result of our involvement with ATC. In addition, we had a receivable of $39.9 million recorded at December 31, 2017 for distributions from ATC. We also had $24.0 million and $31.2 million of accounts payable due to ATC at March 31, 2018 and December 31, 2017, respectively, for network transmission services.

We also own approximately 75% of ATC Holdco, a separate entity formed in December 2016 to invest in transmission-related projects outside of ATC's traditional footprint. We have determined that ATC Holdco is a variable interest entity but that consolidation is not required since we are not ATC Holdco's primary beneficiary. As a result of our limited voting rights, we do not have the power to direct the activities that most significantly impact ATC Holdco's economic performance. We account for ATC Holdco as an equity method investment. The only significant asset or liability related to ATC Holdco recorded on our balance sheets was our equity investment of $37.8 million and $37.6 million at March 31, 2018 and December 31, 2017, respectively. Our equity investment approximates our maximum exposure to loss as a result of our involvement with ATC Holdco.

See Note 16, Investment in Transmission Affiliates, for more information.

Purchased Power Agreement

We have a purchased power agreement that represents a variable interest. This agreement is for 236 MW of firm capacity from a natural gas-fired cogeneration facility, and we account for it as a capital lease. The agreement includes no minimum energy requirements over the remaining term of approximately four years. We have examined the risks of the entity, including operations, maintenance, dispatch, financing, fuel costs, and other factors, and have determined that we are not the primary beneficiary of the entity. We do not hold an equity or debt interest in the entity, and there is no residual guarantee associated with the purchased power agreement.

We have approximately $67.7 million of required payments over the remaining term of this agreement. We believe that the required lease payments under this contract will continue to be recoverable in rates. Total capacity and lease payments under this contract for the three months ended March 31, 2018 and 2017 were $4.7 million and $4.5 million, respectively. Our maximum exposure to loss is limited to the capacity payments under the contract.

XML

COMMITMENTS AND CONTINGENCIES

3 Months Ended

Mar. 31, 2018

Commitments and Contingencies Disclosure [Abstract]

COMMITMENTS AND CONTINGENCIES

COMMITMENTS AND CONTINGENCIES

We and our subsidiaries 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

Our electric utilities have obligations to distribute and sell electricity to their customers, and our natural gas utilities have obligations to distribute and sell natural gas to their customers. The utilities 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. Our minimum future commitments related to these purchase obligations as of March 31, 2018, including those of our subsidiaries, were $11,473.4 million. This amount excludes WPS's purchase obligations under a power purchase agreement with Forward Wind Energy Center, as the agreement was terminated on April 2, 2018, in connection with the acquisition of the facility. See Note 2, Acquisitions, for more information.

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 sulfur dioxide, nitrogen oxide, fine particulates, mercury, and GHGs; water intake and discharges; disposal of coal combustion products such as fly ash; and remediation of impacted properties, including former manufactured gas plant sites.

Air Quality

8-Hour Ozone National Ambient Air Quality Standards

After completing its review of the 2008 ozone standard, the EPA released a final rule in October 2015, which lowered the limit for ground-level ozone, creating a more stringent standard than the 2008 NAAQS. In December 2017, the EPA informed Wisconsin of its intended area designations of all the counties along Wisconsin's Lake Michigan shoreline, except Brown, Kewaunee, Marinette, and Oconto Counties, as either partial or full nonattainment. Waukesha and Washington counties were also included due to the counties being in the Milwaukee combined statistical area. The EPA issued final nonattainment area designations on May 1, 2018. The final designations differ significantly from the intended nonattainment areas EPA proposed late in December 2017. The following counties were designated as partial nonattainment: Manitowoc, Sheboygan, Northern Milwaukee/Ozaukee shoreline, and Kenosha. Racine, Waukesha, and Washington counties will be designated attainment/unclassifiable. For nonattainment areas, the state of Wisconsin will have to develop a state implementation plan to bring the areas back into attainment. We will be required to comply with this state implementation plan no earlier than 2020. We believe we are well positioned to meet the requirements associated with the ozone standard and do not expect to incur significant costs to comply.

Climate Change

In 2015, the EPA issued a final rule regulating GHG emissions from existing generating units, referred to as the Clean Power Plan, a proposed federal plan and model trading rules as alternatives or guides to state compliance plans, and final performance standards for modified and reconstructed generating units and new fossil-fueled power plants. In October 2015, following publication of the CPP, numerous states (including Wisconsin and Michigan) and other parties filed lawsuits challenging the final rule, including a request to stay the implementation of the final rule pending the outcome of these legal challenges. The D.C. Circuit Court of Appeals denied the stay request, but in February 2016, the Supreme Court stayed the effectiveness of the CPP until disposition of the litigation in the D.C. Circuit Court of Appeals and, to the extent that further appellate review is sought, at the Supreme Court. The D.C. Circuit Court of Appeals heard one case in September 2016, and the other case is still pending. In April 2017, pursuant to motions made by the EPA, the D.C. Circuit Court of Appeals ordered the cases to be held in abeyance. Supplemental briefs were provided addressing whether the cases should be remanded to the EPA rather than held in abeyance. The EPA argued that the cases should continue to be held in abeyance pending the conclusion of the EPA's review of the CPP and any resulting rulemaking.

The CPP seeks to achieve state-specific GHG emission reduction goals by 2030, and would have required states to submit plans by September 2016. The goal of the final rule is to reduce nationwide GHG emissions by 32% from 2005 levels. The rule is seeking GHG emission reductions in Wisconsin and Michigan of 41% and 39%, respectively, below 2012 levels by 2030. Interim goals starting in 2022 would require states to achieve about two-thirds of the 2030 required reduction.

In March 2017, President Trump issued an executive order that, among other things, specifically directs the EPA to review, and if appropriate, initiate proceedings to suspend, revise, or rescind the CPP and related GHG regulations for new, reconstructed, or modified fossil-fueled power plants. As a result of this order and related EPA review, as well as the ongoing legal proceedings, the timelines for the GHG emission reduction goals and all other aspects of the CPP are uncertain. In April 2017, the EPA withdrew the proposed rule for a federal plan and model trading rules that were published in October 2015 for use in developing state plans to implement the CPP or for use in states where a plan is not submitted or approved. In October 2017, the EPA issued a proposed rulemaking to repeal the CPP. In December 2017 the EPA issued an advanced notice of proposed rulemaking to solicit input on whether it is appropriate to replace the CPP. In addition, the Governor of Wisconsin issued an executive order in February 2016, which prohibits state agencies, departments, boards, commissions, or other state entities from developing or promoting the development of a state plan to implement the CPP.

Notwithstanding the uncertain future of the CPP, and given current fuel and technology markets, we continue to evaluate opportunities and actions that preserve fuel diversity, lower costs for our customers, and contribute towards long-term GHG reductions. Our plan is to work with our industry partners, environmental groups, and the State of Wisconsin, with a goal of reducing CO₂ emissions by approximately 40% below 2005 levels by 2030. We have implemented and continue to evaluate numerous options in order to meet our CO₂ reduction goal, such as increased use of existing natural gas combined cycle units, co-firing or switching to natural gas in existing coal-fired units, reduced operation or retirement of existing coal-fired units, addition of new renewable energy resources (wind, solar), and consideration of supply and demand-side energy efficiency and distributed generation. As a result of our generation reshaping plan, we expect to retire 1,800 MW of coal generation by 2020, including Pleasant Prairie power plant (now retired), PIPP, Pulliam power plant, and the jointly-owned Edgewater Unit 4 generation units. See Note 5, Property, Plant, and Equipment, for more information. In addition, we are evaluating our goal, and possible subsequent actions, with respect to national and international efforts to reduce future GHG emissions in order to limit future global temperature increases to less than two degrees Celsius.

We are required to report our CO₂ equivalent emissions from our electric generating facilities under the EPA Greenhouse Gases Reporting Program. For 2017, we reported aggregated CO₂ equivalent emissions of 29.2 million metric tonnes to the EPA. The level of CO₂ and other GHG emissions varies from year to year and is dependent on the level of electric generation and mix of fuel sources, which is determined primarily by demand, the availability of the generating units, the unit cost of fuel consumed, and how our units are dispatched by MISO.

We are also required to report CO₂ equivalent amounts related to the natural gas that our natural gas utilities distribute and sell. For 2017, we reported aggregated CO₂ equivalent emissions of 26.6 million metric tonnes to the EPA.

Water Quality

Clean Water Act Cooling Water Intake Structure Rule

In August 2014, the EPA issued a final regulation under Section 316(b) of the Clean Water Act, which requires that the location, design, construction, and capacity of cooling water intake structures at existing power plants reflect the Best Technology Available (BTA) for minimizing adverse environmental impacts from both impingement (entrapping organisms on water intake screens) and entrainment (drawing organisms into water intake). The rule became effective in October 2014, and applies to all of our existing generating facilities with cooling water intake structures, except for the ERGS units, which were permitted under the rules governing new facilities.

Facility owners must select from seven compliance options available to meet the impingement mortality (IM) reduction standard. The rule requires state permitting agencies to make BTA determinations, subject to EPA oversight, for IM reduction over the next several years as facility permits are reissued. Based on our assessment, we believe that existing technologies at our generating facilities, except for Pulliam Units 7 and 8, satisfy the IM BTA requirements. We plan to retire Pulliam Units 7 and 8 as early as late 2018. Therefore, we are not planning to make alterations to the existing water intake at Pulliam Units 7 and 8. Based on the reissued WPDES permit for Weston, the WDNR will not require physical modifications to the Weston Unit 2 intake structure to meet the IM BTA requirements based on low capacity use of the unit.

BTA determinations must also be made by the WDNR and MDEQ to address entrainment mortality (EM) reduction on a site-specific basis taking into consideration several factors. We have received an EM BTA determination by the WDNR, with EPA concurrence, for our intake modification at Valley Power Plant. There has also been an interim EM BTA determination made by the WDNR as part of the reissued WPDES permit for Weston Units 3 and 4 and we intend to extrapolate these results to assess Weston Unit 2. The entrainment study and other technical information will be used by the DNR to make a final 316(b) determination during the next five year WPDES permit term. At this time, we expect that the WDNR will conclude that the existing cooling tower systems for Weston Units 3 and 4 are BTA for both impingement and entrainment reduction. In addition, the WDNR has initially indicated that based on the low capacity utilization of Weston Unit 2, no impingement mortality reduction technology will be required and further entrainment reduction will not be necessary. Due to our plans to retire Pulliam Units 7 and 8, PIPP, and Pleasant Prairie power plant (now retired), we do not believe that BTA determinations for EM will be necessary for these units. Although we currently believe that existing technologies at PWGS, and OC 5 through OC 8 satisfy the EM BTA requirements, BTA determinations to address EM reduction requirements will not be made until discharge permits are renewed for these units. Until that time, we cannot yet determine what, if any, intake structure or operational modifications will be required to meet the new EM BTA requirements for these units. During 2018, we will continue to evaluate options to address the EM BTA requirements for these units.

We have also provided information to the WDNR and the MDEQ about planned unit retirements. Based on discussions with the MDEQ, if we submit a signed certification stating that PIPP will be retired no later than the end of the next permit cycle (assumed to be October 1, 2023), the EM BTA requirements will be waived. We expect to submit the letter identifying the last operating date for PIPP to the MDEQ during 2018, ahead of when the agency begins processing our pending application for the National Pollutant Discharge Elimination System permit reissuance. For Pulliam Units 7 and 8, we submitted our 2016 and 2017 entrainment studies to the WDNR in December 2017, with the application to renew our existing discharge permit.

We believe our fleet overall is well positioned to meet the new regulation and do not expect to incur significant costs to comply with this regulation.

Steam Electric Effluent Limitation Guidelines

The EPA's final steam electric effluent limitation guidelines (ELG) rule took effect in January 2016. Various petitions challenging the rule were consolidated and are pending in the United States Fifth Circuit Court of Appeals. In April 2017, the EPA issued an administrative stay of certain compliance deadlines while further reviewing the rule. In September 2017, the EPA issued a final rule ("Postponement Rule") to postpone the earliest compliance dates for the bottom ash transport water and wet flue gas desulfurizationwastewater requirements. This rule applies to wastewater discharges from our power plant processes in Wisconsin and Michigan. While the ELG compliance deadlines are postponed, the WDNR and the MDEQ have indicated that they will refrain from incorporating certain new requirements into any reissued discharge permits between 2018 and 2023.

After a final rule is back in effect, the WDNR and MDEQ have indicated that they will modify the state rules as necessary and incorporate the new requirements into our facility permits, which are renewed every five years. Our power plant facilities already have advanced wastewater treatment technologies installed that meet many of the discharge limits established by this rule. However, as currently constructed, the ELG rule will require additional wastewater treatment retrofits as well as installation of other equipment to minimize process water use.

The final rule would phase in new or more stringent requirements related to limits of arsenic, mercury, selenium, and nitrogen in wastewater discharged from wet scrubber systems. New requirements for wet scrubber wastewater treatment would require additional zero liquid discharge or other advanced treatment capital improvements for the OCPP and ERGS. The rule also would require dry fly ash handling, which is already in place at all of our power plants. Dry bottom ash transport systems are required by the new rule, and modifications would be required at OC 7, OC 8, and Weston Unit 3. We are beginning preliminary engineering for compliance with the rule and estimate approximately $70 million would be required to design and install these advanced treatment and bottom ash transport systems. This estimate reflects the planned retirements of certain of our generation plants as a result of our generation reshaping plan discussed in Climate Change above.

Land Quality

Manufactured Gas Plant Remediation

We have identified sites at which our utilities 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. Our natural gas utilities are responsible for the environmental remediation of these sites, some of which are in the EPA Superfund Alternative Approach Program. We are also working with various state jurisdictions in our investigation and remediation planning. These sites are at various stages of investigation, monitoring, remediation, and closure.

In addition, we are coordinating the investigation and cleanup of some of these sites subject to the jurisdiction of the EPA under what is called a "multisite" program. This program involves prioritizing the work to be done at the sites, preparation and approval of documents common to all of the sites, and use of a consistent approach in selecting remedies. At this time, we cannot estimate future remediation costs associated with these sites beyond those described below.

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 related to manufactured gas plant sites:

(in millions)	March 31, 2018		December 31, 2017
Regulatory assets	$	668.2	$	676.6
Reserves for future remediation	617.2		617.2

Enforcement and Litigation Matters

We and our subsidiaries 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 effect on our financial condition or results of operations.

Consent Decrees

Wisconsin Public Service Corporation Consent Decree – Weston and Pulliam Power Plants

In November 2009, the EPA issued a NOV to WPS, which alleged violations of the CAA's New Source Review requirements relating to certain projects completed at the Weston and Pulliam plants from 1994 to 2009. WPS entered into a Consent Decree with the EPA resolving this NOV. This Consent Decree was entered by the United States District Court for the Eastern District of Wisconsin in March 2013.

WPS anticipates retiring Pulliam generating units 7 and 8 near the end of 2018 when certain transmission lines are completed. See Note 5, Property, Plant, and Equipment, for more information about the retirement.

Joint Ownership Power Plants Consent Decree – Columbia and Edgewater

In December 2009, the EPA issued a NOV to Wisconsin Power and Light, the operator of the Columbia and Edgewater plants, and the other joint owners of these plants, including Madison Gas and Electric, WE (former co-owner of an Edgewater unit), and WPS. The NOV alleged violations of the CAA's New Source Review requirements related to certain projects completed at those plants. WPS, along with Wisconsin Power and Light, Madison Gas and Electric, and WE, entered into a Consent Decree with the EPA resolving this NOV. This Consent Decree was entered by the United States District Court for the Western District of Wisconsin in June 2013.

As a result of the continued implementation of the Consent Decree related to the jointly owned Columbia and Edgewater plants, retirement of the Edgewater 4 generating unit was probable at March 31, 2018. The plant must be retired by September 30, 2018. See Note 5, Property, Plant, and Equipment, for more information about the retirement.

XML

SUPPLEMENTAL CASH FLOW INFORMATION

3 Months Ended

Mar. 31, 2018

Additional Cash Flow Elements and Supplemental Cash Flow Information [Abstract]

SUPPLEMENTAL CASH FLOW INFORMATION

SUPPLEMENTAL CASH FLOW INFORMATION

	Three Months Ended March 31
(in millions)	2018			2017
Cash (paid) for interest, net of amount capitalized	$	(68.5	)	$	(56.6	)
Cash received for income taxes, net	0.3			8.9
Significant non-cash transactions
Accounts payable related to construction costs	74.9			116.4
Portion of Bostco real estate holdings sale financed with note receivable *	—			7.0
Amortization of deferred revenue	6.3			6.2

* See Note 3, Disposition, for more information on this sale.

Effective January 1, 2018, we adopted ASU 2016-18, Restricted Cash. Under this ASU, amounts generally described as restricted cash and restricted cash equivalents are included with cash and cash equivalents when reconciling the beginning-of-the period and end-of-the period total amounts shown on the statements of cash flows. As a result, we no longer present transfers between cash and cash equivalents and restricted cash and restricted cash equivalents in the statements of cash flows. Instead, changes in restricted cash are classified as either operating activities, investing activities or financing activities.

The majority of our restricted cash consists of amounts held in the Integrys rabbi trust, which are used to fund participants' benefits under the Integrys deferred compensation plan and certain Integrys non-qualified pension plans. All assets held within the rabbi trust are restricted as they can only be withdrawn from the trust to make qualifying benefit payments. The adoption of ASU 2016-18 resulted in an increase of $7.5 million in net cash flows used by investing activities from what was previously reported for the quarter ended March 31, 2017.

See the following table for a reconciliation of cash and cash equivalents and restricted cash reported within the balance sheets to the sum of the total of the same amounts shown in the statements of cash flows at March 31.

(in millions)	2018		2017
Cash and cash equivalents	$	48.1	$	45.7
Restricted cash included in other current assets	—		0.8
Restricted cash included in other long term assets	23.6		26.9
Cash, cash equivalents, and restricted cash	$	71.7	$	73.4

Our statements of cash flows for the years ended December 31, 2017, 2016, and 2015 were retroactively restated from what was previously presented in our 2017 Annual Report on Form 10-K to reflect the adoption of ASU 2016-18. The impacts to our statements of cash flows from adoption of this standard are reflected in the table below.

	Year Ended December 31, 2017									Year Ended December 31, 2016									Year Ended December 31, 2015
(in millions)	2017 Form 10-K Cash Flows			Impact of ASU 2016-18			Cash Flows After Adoption			2017 Form 10-K Cash Flows			Impact of ASU 2016-18			Cash Flows After Adoption			2017 Form 10-K Cash Flows			Impact of ASU 2016-18			Cash Flows After Adoption
Operating Activities
Change in –
Other current assets	$	(6.0	)	$	(1.1	)	$	(7.1	)	$	103.1		$	0.1		$	103.2		$	(27.2	)	$	—		$	(27.2	)
Other, net	(197.5		)	0.1			(197.4		)	(53.8		)	0.2			(53.6		)	(209.1		)	1.5			(207.6		)
Net cash provided by operating activities	2,079.6			(1.0		)	2,078.6			2,103.5			0.3			2,103.8			1,293.6			1.5			1,295.1
Investing Activities
Withdrawal of restricted cash from rabbi trust for qualifying payments	19.5			(19.5		)	—			26.6			(26.6		)	—			1.4			(1.4		)	—
Proceeds from the sale of investments held in rabbi trust	—			8.7			8.7			—			1.7			1.7			—			126.9			126.9
Purchase of investments held in rabbi trust	—			(3.7		)	(3.7		)	—			(59.2		)	(59.2		)	—			(60.2		)	(60.2		)
Integrys acquisition, net of cash acquired	—			—			—			—			—			—			(1,329.9		)	30.8			(1,299.1		)
Other, net	12.0			—			12.0			3.0			—			3.0			57.0			(1.2		)	55.8
Net cash used in investing activities	(2,239.6		)	(14.5		)	(2,254.1		)	(1,270.1		)	(84.1		)	(1,354.2		)	(2,517.5		)	94.9			(2,422.6		)
Financing Activities
Other, net	(6.5		)	—			(6.5		)	(13.6		)	—			(13.6		)	(18.9		)	22.6			3.7
Net cash provided by (used in) financing activities	161.4			—			161.4			(845.7		)	—			(845.7		)	1,211.8			22.6			1,234.4
Net change in cash, cash equivalents, and restricted cash	1.4			(15.5		)	(14.1		)	(12.3		)	(83.8		)	(96.1		)	(12.1		)	119.0			106.9
Cash, cash equivalents, and restricted cash at beginning of period	37.5			35.2			72.7			49.8			119.0			168.8			61.9			—			61.9
Cash, cash equivalents, and restricted cash at end of period	$	38.9		$	19.7		$	58.6		$	37.5		$	35.2		$	72.7		$	49.8		$	119.0		$	168.8

Effective January 1, 2018, we adopted ASU 2016-15, Classification of Certain Cash Receipts and Cash Payments. There are eight main provisions of this ASU for which current GAAP either was unclear or did not include specific guidance. The adoption of this guidance had no impact on our financial statements for the quarters ended March 31, 2018 and 2017.

ASU 2016-15 provides an accounting policy election for classifying distributions received from equity method investments. We adopted the cumulative earnings approach for classifying distributions received in the statements of cash flows. Under the cumulative earnings approach, we compare the distributions received to cumulative equity method earnings since inception. Any distributions received up to the amount of cumulative equity earnings are considered a return on investment and classified in operating activities. Any excess distributions are considered a return of investment and classified in investing activities. We did not receive any excess distributions for the quarters ended March 31, 2018 and 2017.

XML

REGULATORY ENVIRONMENT

3 Months Ended

Mar. 31, 2018

Regulated Operations [Abstract]

REGULATORY ENVIRONMENT

REGULATORY ENVIRONMENT

Tax Cuts and Jobs Act of 2017

WEC Energy Group's regulated utilities deferred for return to ratepayers, through future refunds, bill credits, riders, or reductions in other regulatory assets, the estimated tax benefit of $2,450 million related to the Tax Legislation that was signed into law in December 2017. This tax benefit resulted from the revaluation of deferred taxes in December 2017. The current 2018 tax benefit related to the Tax Legislation, which reduced the corporate federal tax rate from a maximum of 35% to a 21% rate, effective January 1, 2018, is also being deferred for return to ratepayers.

We have not received a written order in any of our jurisdictions addressing the refunding of these amounts to date other than the rider approved in Illinois. See Variable Income Tax Adjustment Rider below for more information on this Illinois rider. Our proposed approach for the remaining jurisdictions is outlined below.

Wisconsin

In April 2018, the PSCW issued a preliminary determination regarding the benefits associated with the Tax Legislation. For our Wisconsin electric utility operations, the PSCW indicated that 80% of the current 2018 and 2019 tax benefits should be used to reduce certain regulatory assets at WE and WPS, with the remaining 20% returned to electric customers in the form of bill credits. For our Wisconsin natural gas utility operations, the PSCW indicated that 100% of current 2018 and 2019 tax benefits should be returned to natural gas customers in the form of bill credits. Regarding the net tax benefit associated with the revaluation of deferred taxes, amortization required in accordance with normalization accounting for our electric utilities should be used to reduce certain regulatory assets, while the timing and method of returning the remaining net tax benefit associated with the revaluation of deferred taxes was not addressed and will be determined in a future rate proceeding. Until we receive the final written order, the specific terms are subject to change.

Michigan

In February 2018, the MPSC issued an order requiring Michigan utilities to make three filings related to the Tax Legislation. The first of those filings, which was filed in March 2018, prospectively addresses the impact on base rates for the change in tax expense resulting from the federal tax rate reduction from 35% to 21%. For UMERC and MGU, the proposed approach is to provide a volumetric bill credit, subject to reconciliation and true up. The second filing will be due 30 days after the MPSC issues an order on the first filing and is required to address the impact on base rates for the change in tax expense resulting from the federal tax rate reduction from 35% to 21% from January 1, 2018, until the effective date of the initial filing. The third filing, which is due in October 2018, will address the remaining impacts of the Tax Legislation on base rates - most notably the re-measurement of deferred tax balances. UMERC and MGU have not yet made a proposal on the second and third filings.

WE, which serves one retail electric customer in Michigan, has reached a settlement with that customer. That settlement has been filed with the MPSC in March 2018 and addresses all base rate impacts of the Tax Legislation.

Minnesota

MERC is currently in an active rate case for 2018 and expects to address all aspects of the Tax Legislation, including the re-measurement of deferred tax balances, in that rate case. MERC expects that all impacts of the Tax Legislation will be incorporated into base rates when they are approved by the MPUC during the active rate proceeding.

Wisconsin Electric Power Company, Wisconsin Gas LLC, and Wisconsin Public Service Corporation

2018 and 2019 Rates

During April 2017, WE, WG, and WPS filed an application with the PSCW for approval of a settlement agreement they made with several of their commercial and industrial customers regarding 2018 and 2019 base rates. In September 2017, the PSCW issued an order that approved the settlement agreement, which will freeze base rates through 2019 for electric, gas, and steam customers of WE, WG, and WPS. Based on the PSCW order, the authorized ROE for WE, WG, and WPS remains at 10.2%, 10.3%, and 10.0%, respectively, and the current capital cost structure for all of our Wisconsin utilities will remain unchanged through 2019. Various intervenors had filed requests for rehearing, all of which have been denied.

In addition to freezing base rates, the settlement agreement extends and expands the electric real-time market pricing program options for large commercial and industrial customers and mitigates the continued growth of certain escrowed costs at WE during the base rate freeze period by accelerating the recognition of certain tax benefits. WE will flow through the tax benefit of its repair-related deferred tax liabilities in 2018 and 2019, to maintain certain regulatory asset balances at their December 31, 2017 levels. While WE would typically follow the normalization accounting method and utilize the tax benefits of the deferred tax liabilities in rate making as an offset to rate base, benefiting customers over time, the federal tax code does allow for passing these tax repair-related benefits to ratepayers much sooner using the flow through accounting method. The flow through treatment of the repair related deferred tax liabilities offsets the negative income statement impact of holding the regulatory assets level, resulting in no change to net income.

The agreement also allows WPS to extend through 2019, the deferral for the revenue requirement of ReACT™ costs above the authorized $275.0 million level, and other deferrals related to WPS's electric real-time market pricing program and network transmission expenses. The total cost of the ReACT™ project, excluding $51 million of AFUDC, is currently estimated to be $342 million.

Pursuant to the settlement agreement, WPS also agreed to adopt, beginning in 2018, the earnings sharing mechanism that has been in place for WE and WG since January 2016, and all three utilities agreed to keep the mechanism in place through 2019. Under this earnings sharing mechanism, if WE, WG, or WPS earns above its authorized ROE, 50% of the first 50 basis points of additional utility earnings must be shared with customers. All utility earnings above the first 50 basis points must also be shared with customers.

Acquisition of a Wind Energy Generation Facility in Wisconsin

In October 2017, WPS, along with two other unaffiliated utilities, entered into an agreement to purchase the Forward Wind Energy Center, which consists of 86 wind turbines located in Wisconsin with a total capacity of 129 MW. The FERC approved the transaction in January 2018, and the PSCW approved the transaction in March 2018. The transaction closed on April 2, 2018. See Note 2, Acquisitions, for more information.

Natural Gas Storage Facilities in Michigan

In January 2017, we signed an agreement for the acquisition of Bluewater. Bluewater owns natural gas storage facilities in Michigan that are providing approximately one-third of the current storage needs for the natural gas operations of WE, WG, and WPS. As a result of this agreement, WE, WG, and WPS filed a request with the PSCW in February 2017 for a declaratory ruling on various items associated with the storage facilities. In the filing, WE, WG, and WPS requested that the PSCW review and confirm the reasonableness and prudency of their potential long-term storage service agreements and interstate natural gas transportation contracts related to the storage facilities. WE, WG, and WPS also requested approval to amend our Affiliated Interest Agreement to ensure WBS and our other subsidiaries could provide services to the storage facilities. The PSCW granted, subject to various conditions, these declarations and approvals, and we acquired Bluewater on June 30, 2017. In September 2017, WE, WG, and WPS finalized the long-term service agreements for the natural gas storage, which were approved by the PSCW in November 2017. See Note 2, Acquisitions, for more information.

The Peoples Gas Light and Coke Company and North Shore Gas Company

Illinois Proceedings

In December 2015, the ICC ordered a series of stakeholder workshops to evaluate PGL's SMP. This ICC action did not impact PGL's ongoing work to modernize and maintain the safety of its natural gas distribution system, but it instead provided the ICC with an opportunity to analyze long-term elements of the program through the stakeholder workshops. The workshops were completed in March 2016. In July 2016, the ICC initiated a proceeding to review, among other things, the planning, reporting, and monitoring of the program, including the target end date for the program, and issued a final order in January 2018. The order did not have a significant impact on PGL's existing SMP design and execution. An appeal related to the final order was filed by the Illinois Attorney General in April 2018.

Qualifying Infrastructure Plant Rider

In July 2013, Illinois Public Act 98-0057, The Natural Gas Consumer, Safety & Reliability Act, became law. This law provides PGL with a cost recovery mechanism that allows collection, through a surcharge on customer bills, of prudently incurred costs to upgrade Illinois natural gas infrastructure. In September 2013, PGL filed with the ICC requesting the proposed rider, which was approved in January 2014.

PGL's QIP rider is subject to an annual reconciliation whereby costs are reviewed for accuracy and prudency. In March 2018, PGL filed its 2017 reconciliation with the ICC, which, along with the 2016 and 2015 reconciliations, are still pending. In February 2018, PGL agreed to a settlement of the 2014 reconciliation, which includes a rate base reduction of $5.4 million and a $4.7 million refund to ratepayers.

As of March 31, 2018, there can be no assurance that all costs incurred under PGL's QIP rider during the open reconciliation years will be deemed recoverable by the ICC.

Variable Income Tax Adjustment Rider

In April 2018, the ICC approved the VITA proposed by PGL and NSG. The VITA recovers or refunds changes in income tax expense resulting from differences in income tax rates and amortization of deferred tax excesses and deficiencies (in accordance with the Tax Legislation) from the amounts used in the Company's last rate case effective January 25, 2018. See Note 10, Income Taxes, for more information.

Minnesota Energy Resources Corporation

2018 Minnesota Rate Case

In October 2017, MERC initiated a rate proceeding with the MPUC to increase retail natural gas rates $12.6 million (5.05%). MERC's request reflected a 10.3% ROE and a common equity component average of 50.9%. In November 2017, the MPUC approved an interim rate order, effective January 1, 2018, authorizing a retail natural gas rate increase of $9.5 million (3.78%). In March 2018, to reflect changes in MERC's effective tax rate as a result of the enactment of the Tax Legislation, the MPUC approved a $2.5 million reduction in interim retail natural gas rates to $7.0 million (2.81%), effective April 1, 2018. The interim rates reflect a 9.1% ROE and a common equity component average of 50.9%. The interim rate increase is subject to refund pending the final written rate order, which is expected in the first half of 2019.

Upper Michigan Energy Resources Corporation

Formation of Upper Michigan Energy Resources Corporation

In December 2016, both the MPSC and the PSCW approved the operation of UMERC as a stand-alone utility in the Upper Peninsula of Michigan, and UMERC became operational effective January 1, 2017. This utility holds the electric and natural gas distribution assets, previously held by WE and WPS, located in the Upper Peninsula of Michigan.

In August 2016, we entered into an agreement with the Tilden Mining Company (Tilden), under which Tilden will purchase electric power from UMERC for its iron ore mine for 20 years, contingent upon UMERC's construction of approximately 180 MW of natural gas-fired generation in the Upper Peninsula of Michigan.

In October 2017, the MPSC approved both the agreement with Tilden and UMERC's application for a certificate of necessity to begin construction of the proposed generation. The estimated cost of this project is $266 million ($277 million with AFUDC), 50% of which is expected to be recovered from Tilden, with the remaining 50% expected to be recovered from UMERC's other utility customers. The new units are expected to begin commercial operation by mid-2019. Upon receiving the MPSC's approval, retirement of the PIPP generating units became probable. As a result of a MISO ruling received in April 2018, the PIPP units must be retired no later than May 31, 2019. Tilden will remain a customer of WE until this new generation begins commercial operation.

XML

NEW ACCOUNTING PRONOUNCEMENTS

3 Months Ended

Mar. 31, 2018

New Accounting Pronouncements and Changes in Accounting Principles [Abstract]

NEW ACCOUNTING PRONOUNCEMENTS

NEW ACCOUNTING PRONOUNCEMENTS

Leases

In February 2016, the FASB issued ASU 2016-02, Leases. This guidance is effective for fiscal years, and interim periods within those fiscal years, beginning after December 15, 2018, and will be applied using a modified retrospective approach. The main provision of this ASU is that lessees will be required to recognize lease assets and lease liabilities for most leases, including those classified as operating leases under GAAP. We are currently assessing the effects this guidance may have on our financial statements.

Financial Instruments Credit Losses

In June 2016, the FASB issued ASU 2016-13, Measurement of Credit Losses on Financial Instruments. This guidance is effective for fiscal years, and interim periods within those fiscal years, beginning after December 15, 2019. This ASU introduces a new impairment model known as the current expected credit loss model. The ASU requires a financial asset measured at amortized cost to be presented at the net amount expected to be collected. Previously, recognition of the full amount of credit losses was generally delayed until the loss was probable of occurring. We are currently assessing the effects this guidance may have on our financial statements.

XML

GENERAL INFORMATION (Policies)

3 Months Ended

Mar. 31, 2018

Accounting policies

Consolidation

As used in these notes, the term "financial statements" refers to the condensed consolidated financial statements. This includes the income statements, statements of comprehensive income, balance sheets, and statements of cash flows, unless otherwise noted. In this report, when we refer to "the Company," "us," "we," "our," or "ours," we are referring to WEC Energy Group and all of its subsidiaries.

Basis of Accounting

We have prepared the unaudited interim financial statements presented in this Form 10-Q pursuant to the rules and regulations of the SEC and GAAP. Accordingly, these financial statements do not include all of the information and footnotes required by GAAP for annual financial statements. These financial statements should be read in conjunction with the consolidated financial statements and footnotes in our Annual Report on Form 10-K for the year ended December 31, 2017. Financial results for an interim period may not give a true indication of results for the year. In particular, the results of operations for the three months ended March 31, 2018, are not necessarily indicative of expected results for 2018 due to seasonal variations and other factors.

In management's opinion, we have included all adjustments, normal and recurring in nature, necessary for a fair presentation of our financial results.

Fair Value Measurement

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 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 financial 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 are categorized in Level 3 due to the significance of unobservable or internally-developed inputs.

We recognize transfers between levels of the fair value hierarchy at their value as of the end of the reporting period.

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 and shareholders. Our approach is non-speculative and designed to mitigate risk. Regulated hedging programs are approved by our state regulators.

We record derivative instruments on our balance sheets as an asset or liability 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, our regulators allow the effects of fair value accounting to be offset to regulatory assets and liabilities.

New Accounting Pronouncements

Leases

In February 2016, the FASB issued ASU 2016-02, Leases. This guidance is effective for fiscal years, and interim periods within those fiscal years, beginning after December 15, 2018, and will be applied using a modified retrospective approach. The main provision of this ASU is that lessees will be required to recognize lease assets and lease liabilities for most leases, including those classified as operating leases under GAAP. We are currently assessing the effects this guidance may have on our financial statements.

Financial Instruments Credit Losses

In June 2016, the FASB issued ASU 2016-13, Measurement of Credit Losses on Financial Instruments. This guidance is effective for fiscal years, and interim periods within those fiscal years, beginning after December 15, 2019. This ASU introduces a new impairment model known as the current expected credit loss model. The ASU requires a financial asset measured at amortized cost to be presented at the net amount expected to be collected. Previously, recognition of the full amount of credit losses was generally delayed until the loss was probable of occurring. We are currently assessing the effects this guidance may have on our financial statements.

Electric

Accounting policies

Revenue Recognition

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 Wisconsin residential and commercial and industrial customers and the majority of our Michigan residential and commercial and industrial customers, our performance obligation is bundled and consists of both the sale and the delivery of the electric commodity. In our Michigan service territory, a limited number of residential and commercial and industrial customers can purchase the commodity from a third party. In this case, the delivery of the electricity represents our sole performance obligation. The rates, charges, terms, and conditions of service for sales to these customers are included in tariffs that have been approved by state regulators. These rates often have a fixed component customer charge and a usage-based variable component. 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 using an output method based on the quantity of electricity delivered each month.

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 our utilities provide generation to match the customer's load, similar to requirements contracts, or they can purchase specified quantities of electricity and capacity. The rates, charges, terms and conditions of service for sales to wholesale customers are included in tariffs that have been approved by the FERC. 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 utilities 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.

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. 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. 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.

Natural gas

Accounting policies

Revenue Recognition

We recognize natural gas utility operating revenues under requirements contracts with residential, commercial and industrial, and transportation customers served under the tariffs of our regulated utilities. 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 certain of our service territories, 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 is valued using rates in the tariffs of our regulated utilities, which have been approved by state regulators. These rates often have a fixed component customer charge and a usage-based variable component. 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 using an output method based on natural gas delivered each month.

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 non-utility revenues

Accounting policies

Revenue Recognition

As part of the construction of the We Power electric generating units, we capitalized interest during construction, which is included in property, plant, and equipment. As allowed by the PSCW, we collected these carrying costs from WE's utility customers during construction. The equity portion of these carrying costs was recorded as deferred revenue, and we continually amortize the deferred carrying costs to revenues over the life of the plants to better match the costs of owning the plant while we are providing service to our customers. During the three months ended March 31, 2018, we recorded $6.4 million of revenue related to these deferred carrying costs, which were included in the contract liability balance at the beginning of the period. This contract liability is presented as deferred revenue, net on our balance sheets.

Non-utility operating revenues are derived primarily from servicing appliances for customers at MERC. These contracts customarily have a duration of one year or less and consist of a single performance obligation satisfied over time. We use a time-based output method to recognize revenues monthly for the service fee.

Revenues from distributed renewable solar projects consist primarily of sales of renewable energy and solar renewable energy certificates (SRECs) generated by WPS Power Development, LLC. The sale of SRECs is a distinct performance obligation as they are often sold separately from the renewable energy generated. Although the performance obligation for the sale of renewable energy is recognized over time and the performance obligation for SRECs is recognized at a point-in-time, the timing of revenue recognition is the same and occurs as renewable energy is generated.

Alternative revenues

Accounting policies

Revenue Recognition

Alternative Revenues

Alternative revenues are created from programs authorized by regulators that allow our utilities 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. Alternative revenue programs allow compensation for the effects of weather abnormalities, other external factors, or demand side management initiatives. Alternative revenue programs can also provide incentive awards if the utility achieves certain objectives and in other limited circumstances. 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.

Below is a summary of the alternative revenue programs at our utilities:

• The rates of PGL, NSG, and MERC include decoupling mechanisms. These mechanisms differ by state and allow the utilities to recover or refund the differences between actual and authorized margins for certain customers.

• MERC’s rates include a conservation improvement program rider, which includes a financial incentive for meeting energy savings goals.

• WE and WPS provide wholesale electric service 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 or refund to the customer. We consider the true-up portion of the wholesale electric revenues to be alternative revenues.

XML

ACQUISITIONS (Tables)

3 Months Ended

Mar. 31, 2018

Business Combinations [Abstract]

Allocation of purchase price

The table below shows the allocation of the purchase price to the assets acquired and liabilities assumed at the date of the acquisition. The excess of the purchase price over the estimated fair values of the assets acquired and liabilities assumed was recognized as goodwill. Bluewater is included in the non-utility energy infrastructure segment. See Note 17, Segment Information, for more information.

(in millions)
Current assets	$	2.0
Net property, plant, and equipment	218.3
Goodwill	6.6
Current liabilities	(0.9		)
Total purchase price	$	226.0

XML

OPERATING REVENUES (Tables)

3 Months Ended

Mar. 31, 2018

Disaggregation of Operating Revenues

Operating revenues disaggregated by revenue source

The following tables present our operating revenues disaggregated by revenue source. Comparable amounts have not been presented for the three months ended March 31, 2017, due to our adoption of this standard under the modified retrospective method.

(in millions)	Wisconsin		Illinois			Other States			Total Utility Operations			Electric Transmission		Non-Utility Energy Infrastructure		Corporate and Other		Reconciling Eliminations			WEC Energy Group Consolidated
Three Months Ended March 31, 2018
Electric	$	1,067.7	$	—		$	—		$	1,067.7		$	—	$	—	$	—	$	—		$	1,067.7
Natural gas	518.0		507.6			172.7			1,198.3			—		14.9		—		(2.5		)	1,210.7
Total utility revenues	1,585.7		507.6			172.7			2,266.0			—		14.9		—		(2.5		)	2,278.4
Other non-utility revenues	—		—			3.9			3.9			—		7.1		1.3		(0.7		)	11.6
Total revenues from contracts with customers	1,585.7		507.6			176.6			2,269.9			—		22.0		1.3		(3.2		)	2,290.0
Other operating revenues	3.4		(0.3		)	(6.7		)	(3.6		)	—		96.1		0.1		(96.1		)	(3.5		)
Total operating revenues	$	1,589.1	$	507.3		$	169.9		$	2,266.3		$	—	$	118.1	$	1.4	$	(99.3	)	$	2,286.5

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 for the current period:

(in millions)	Electric Utility Operating Revenues
Three Months Ended March 31, 2018
Residential	$	384.3
Small commercial and industrial	330.7
Large commercial and industrial	203.9
Other	7.7
Total retail revenues	926.6
Wholesale	54.9
Resale	73.8
Steam	9.7
Other utility revenues	2.7
Total electric utility operating revenues	$	1,067.7

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 for the current period:

(in millions)	Wisconsin			Illinois			Other States			Total Natural Gas Utility Operations
Three Months Ended March 31, 2018
Residential	$	356.7		$	332.6		$	123.2		$	812.5
Commercial and industrial	187.9			109.4			64.7			362.0
Total retail revenues	544.6			442.0			187.9			1,174.5
Transport	21.0			77.7			9.9			108.6
Other utility revenues *	(47.6		)	(12.1		)	(25.1		)	(84.8		)
Total natural gas utility operating revenues	$	518.0		$	507.6		$	172.7		$	1,198.3

* Includes amounts (refunded to) collected from customers for purchased gas adjustment costs.

Revenues from contracts with customers | Other non-utility revenues

Disaggregation of Operating Revenues

Operating revenues disaggregated by revenue source

Other non-utility operating revenues consist primarily of the following:

(in millions)	Three Months Ended March 31, 2018
We Power revenues	$	6.4
Appliance service revenues	3.9
Distributed renewable solar project revenues	1.3
Total other non-utility operating revenues	$	11.6

Other operating revenues

Disaggregation of Operating Revenues

Operating revenues disaggregated by revenue source

Other operating revenues consist primarily of the following:

(in millions)	Three Months Ended March 31, 2018
Alternative revenues *	$	(16.1	)
Late payment charges	11.4
Leases	1.2
Total other operating revenues	$	(3.5	)

* Negative amounts can result from alternative revenues being reversed to revenues from contracts with customers as the customer is billed for these alternative revenues. Negative amounts can also result from revenues to be refunded to customers subject to decoupling mechanisms and wholesale true-ups, as discussed below.

XML

COMMON EQUITY (Tables)

3 Months Ended

Mar. 31, 2018

Equity [Abstract]

Schedule of stock-based compensation awards granted

During the first quarter of 2018, the Compensation Committee of our Board of Directors awarded the following stock-based compensation awards to our directors, officers, and certain other key employees:

Award Type	Number of Awards
Stock options (1)	710,710
Restricted shares (2)	156,340
Performance units	217,560

⁽¹⁾  Stock options awarded had a weighted-average exercise price of $65.60 and a weighted-average grant date fair value of $7.71 per option.

⁽²⁾  Restricted shares awarded had a weighted-average grant date fair value of $64.20 per share.

XML

SHORT-TERM DEBT AND LINES OF CREDIT (Tables)

3 Months Ended

Mar. 31, 2018

Short-term Debt [Abstract]

Schedule of short-term borrowings and weighted-average interest rates

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

(in millions, except percentages)	March 31, 2018			December 31, 2017
Commercial paper
Amount outstanding	$	1,200.3		$	1,444.6
Weighted-average interest rate on amounts outstanding	2.24		%	1.77		%

Schedule of revolving credit facilities and remaining available capacity

The information in the table below relates to our revolving credit facilities used to support our commercial paper borrowing programs, including available capacity under these facilities:

(in millions)	Maturity	March 31, 2018
WEC Energy Group	October 2022	$	1,200.0
WE	October 2022	500.0
WPS	October 2022	400.0
WG	October 2022	350.0
PGL	October 2022	350.0
Total short-term credit capacity		$	2,800.0
Less:
Letters of credit issued inside credit facilities		$	1.2
Commercial paper outstanding		1,200.3
Available capacity under existing agreements		$	1,598.5

XML

MATERIALS, SUPPLIES, AND INVENTORIES (Tables)

3 Months Ended

Mar. 31, 2018

Inventory Disclosure [Abstract]

Schedule of inventory

Our inventory consisted of:

(in millions)	March 31, 2018		December 31, 2017
Natural gas in storage	$	34.8	$	209.0
Materials and supplies	213.7		211.2
Fossil fuel	127.5		118.8
Total	$	376.0	$	539.0

XML

INCOME TAXES (Tables)

3 Months Ended

Mar. 31, 2018

Income Tax Disclosure [Abstract]

Schedule of Effective Income Tax Rate Reconciliation

The provision for income taxes for the quarter ended March 31, 2018, 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:

	Amount			Effective Tax Rate
Statutory federal income tax	$	100.5		21.0	%
State income taxes net of federal tax benefit	29.9			6.2	%
Federal tax reform	(15.5		)	(3.2	)%
Tax repairs	(25.5		)	(5.3	)%
Other	(1.1		)	(0.3	)%
Total income tax expense	$	88.3		18.4	%

XML

FAIR VALUE MEASUREMENTS (Tables)

3 Months Ended

Mar. 31, 2018

Fair Value Disclosures [Abstract]

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:

	March 31, 2018
(in millions)	Level 1		Level 2		Level 3		Total
Derivative assets
Natural gas contracts	$	1.7	$	0.5	$	—	$	2.2
Petroleum products contracts	0.6		—		—		0.6
FTRs	—		—		1.5		1.5
Coal contracts	—		1.1		—		1.1
Total derivative assets	$	2.3	$	1.6	$	1.5	$	5.4
Investments held in rabbi trust	$	103.6	$	—	$	—	$	103.6
Derivative liabilities
Natural gas contracts	$	3.4	$	1.4	$	—	$	4.8
Coal contracts	—		0.3		—		0.3
Total derivative liabilities	$	3.4	$	1.7	$	—	$	5.1

	December 31, 2017
(in millions)	Level 1		Level 2		Level 3		Total
Derivative assets
Natural gas contracts	$	1.8	$	3.9	$	—	$	5.7
Petroleum products contracts	1.2		—		—		1.2
FTRs	—		—		4.4		4.4
Coal contracts	—		1.1		—		1.1
Total derivative assets	$	3.0	$	5.0	$	4.4	$	12.4
Investments held in rabbi trust	$	120.7	$	—	$	—	$	120.7
Derivative liabilities
Natural gas contracts	$	7.0	$	3.8	$	—	$	10.8
Coal contracts	—		0.8		—		0.8
Total derivative liabilities	$	7.0	$	4.6	$	—	$	11.6

Reconciliation 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:

	Three Months Ended March 31
(in millions)	2018			2017
Balance at the beginning of the period	$	4.4		$	5.1
Settlements	(2.9		)	(3.4		)
Balance at the end of the period	$	1.5		$	1.7

Schedule of carrying value and estimated 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:

	March 31, 2018				December 31, 2017
(in millions)	Carrying Amount		Fair Value		Carrying Amount		Fair Value
Preferred stock	$	30.4	$	29.1	$	30.4	$	30.5
Long-term debt, including current portion *	9,549.3		10,054.5		9,561.7		10,341.9

* The carrying amount of long-term debt excludes capital lease obligations of $26.1 million and $27.0 million at March 31, 2018 and December 31, 2017, respectively.

XML

DERIVATIVE INSTRUMENTS (Tables)

3 Months Ended

Mar. 31, 2018

Derivative Instruments and Hedging Activities Disclosure [Abstract]

Derivative assets and derivative liabilities

The following table shows our derivative assets and derivative liabilities:

	March 31, 2018				December 31, 2017
(in millions)	Derivative Assets		Derivative Liabilities		Derivative Assets		Derivative Liabilities
Other current
Natural gas contracts	$	2.2	$	3.7	$	5.6	$	9.4
Petroleum products contracts	0.6		—		1.2		—
FTRs	1.5		—		4.4		—
Coal contracts	0.8		0.3		0.6		0.6
Total other current *	$	5.1	$	4.0	$	11.8	$	10.0
Other long-term
Natural gas contracts	$	—	$	1.1	$	0.1	$	1.4
Coal contracts	0.3		—		0.5		0.2
Total other long-term *	$	0.3	$	1.1	$	0.6	$	1.6
Total	$	5.4	$	5.1	$	12.4	$	11.6

* On our balance sheets, we classify derivative assets and liabilities as other current or other long-term based on the maturities of the underlying contracts.

Estimated notional volumes and realized gain (losses)

Our estimated notional sales volumes and realized gains (losses) were as follows:

	Three Months Ended March 31, 2018				Three Months Ended March 31, 2017
(in millions)	Volumes	Gains (Losses)			Volumes	Gains (Losses)
Natural gas contracts	48.1 Dth	$	(5.2	)	34.1 Dth	$	(0.3	)
Petroleum products contracts	2.1 gallons	0.5			4.9 gallons	(0.5		)
FTRs	8.2 MWh	3.7			9.2 MWh	3.0
Total		$	(1.0	)		$	2.2

Offsetting assets and liabilities

The following table shows derivative assets and derivative liabilities if derivative instruments by counterparty were presented net on our balance sheets:

	March 31, 2018							December 31, 2017
(in millions)	Derivative Assets			Derivative Liabilities				Derivative Assets			Derivative Liabilities
Gross amount recognized on the balance sheet	$	5.4		$	5.1			$	12.4		$	11.6
Gross amount not offset on the balance sheet	(2.1		)	(3.7		)	(1)	(4.9		)	(9.0		)	(2)
Net amount	$	3.3		$	1.4			$	7.5		$	2.6

⁽¹⁾   Includes cash collateral posted of $1.6 million.

⁽²⁾  Includes cash collateral posted of $4.1 million.

XML

GUARANTEES (Tables)

3 Months Ended

Mar. 31, 2018

Guarantees [Abstract]

Schedule of outstanding guarantees

The following table shows our outstanding guarantees:

			Expiration
(in millions)	Total Amounts Committed at March 31, 2018		Less Than 1 Year		1 to 3 Years		Over 3 Years
Guarantees
Guarantees supporting commodity transactions of subsidiaries (1)	$	8.1	$	8.1	$	—	$	—
Standby letters of credit (2)	71.4		46.0		25.4		—
Surety bonds (3)	9.8		9.7		0.1		—
Other guarantees (4)	11.1		0.5		—		10.6
Total guarantees	$	100.4	$	64.3	$	25.5	$	10.6

⁽¹⁾  Consists of $8.1 million to support the business operations of Bluewater.

⁽²⁾  At our request or the request of our subsidiaries, financial institutions have issued standby letters of credit for the benefit of third parties that have extended credit to our subsidiaries. These amounts are not reflected on our balance sheets.

⁽³⁾  Primarily for workers compensation self-insurance programs and obtaining various licenses, permits, and rights-of-way. These amounts are not reflected on our balance sheets.

⁽⁴⁾  Consists of $11.1 million related to other indemnifications, for which a liability of $10.6 million related to workers compensation coverage was recorded on our balance sheets.

XML

EMPLOYEE BENEFITS (Tables)

3 Months Ended

Mar. 31, 2018

Retirement Benefits [Abstract]

Schedule of Net Benefit Costs

The following tables show the components of net periodic pension and OPEB costs for our benefit plans.

	Pension Costs
	Three Months Ended March 31
(in millions)	2018			2017
Service cost	$	12.0		$	11.7
Interest cost	28.3			31.2
Expected return on plan assets	(49.6		)	(49.6		)
Loss on plan settlement	0.4			—
Amortization of prior service cost	0.7			0.7
Amortization of net actuarial loss	23.1			21.9
Net periodic benefit cost	$	14.9		$	15.9

	OPEB Costs
	Three Months Ended March 31
(in millions)	2018			2017
Service cost	$	6.2		$	6.3
Interest cost	7.5			8.5
Expected return on plan assets	(14.9		)	(13.7		)
Amortization of prior service credit	(3.8		)	(2.8		)
Amortization of net actuarial loss	0.3			1.5
Net periodic benefit credit	$	(4.7	)	$	(0.2	)

Schedule of retroactively restated Income Statement

The impacts to our income statements from adoption of this standard are reflected in the table below.

	Year Ended December 31, 2017						Year Ended December 31, 2016							Year Ended December 31, 2015
(in millions)	Form 10-K Income Statement		Impact of ASU 2017-07		Income Statement After Adoption		Form 10-K Income Statement		Impact of ASU 2017-07			Income Statement After Adoption		Form 10-K Income Statement		Impact of ASU 2017-07		Income Statement After Adoption
Operating expenses
Other operation and maintenance	$	2,047.0	$	9.1	$	2,056.1	$	2,185.5	$	(14.2	)	$	2,171.3	$	1,709.3	$	1.4	$	1,710.7
Other expense
Other income, net	64.6		9.1		73.7		80.8		(14.2		)	66.6		58.9		1.4		60.3

XML

GOODWILL (Tables)

3 Months Ended

Mar. 31, 2018

Goodwill and Intangible Assets Disclosure [Abstract]

Schedule of changes to our goodwill balances by segment

The following table shows changes to our goodwill balances by segment during the three months ended March 31, 2018:

(in millions)	Wisconsin		Illinois		Other States		Non-Utility Energy Infrastructure			Total
Goodwill balance as of January 1, 2018	$	2,104.3	$	758.7	$	183.2	$	7.3		$	3,053.5
Adjustment to Bluewater purchase price allocation (1)	—		—		—		(0.7		)	(0.7		)
Goodwill balance as of March 31, 2018 (2)	$	2,104.3	$	758.7	$	183.2	$	6.6		$	3,052.8

⁽¹⁾  See Note 2, Acquisitions, for more information on the acquisition of Bluewater.

⁽²⁾  We had no accumulated impairment losses related to our goodwill as of March 31, 2018.

XML

INVESTMENT IN TRANSMISSION AFFILIATES (Tables)

3 Months Ended

Mar. 31, 2018

Investment in Transmission Affiliates

Schedule of changes to our investment in Transmission Affiliates

The following tables provide a reconciliation of the changes in our investments in ATC and ATC Holdco:

	Three Months Ended March 31, 2018
(in millions)	ATC		ATC Holdco			Total
Balance at beginning of period *	$	1,515.8	$	37.6		$	1,553.4
Add: Earnings (loss) from equity method investment	33.4		(0.6		)	32.8
Add: Capital contributions	12.0		0.8			12.8
Less: Other	0.1		—			0.1
Balance at end of period	$	1,561.1	$	37.8		$	1,598.9

* Distributions of $39.9 million, received in the first quarter of 2018, were approved and recorded as a receivable from ATC in other current assets at December 31, 2017.

	Three Months Ended March 31, 2017
(in millions)	ATC		ATC Holdco			Total
Balance at beginning of period *	$	1,443.9	$	—		$	1,443.9
Add: Earnings (loss) from equity method investment	47.7		(5.8		)	41.9
Add: Capital contributions	24.1		3.5			27.6
Less: Other	0.1		—			0.1
Balance at end of period	$	1,515.6	$	(2.3	)	$	1,513.3

* Distributions of $35.2 million, received in the first quarter of 2017, were approved and recorded as a receivable from ATC in other current assets at December 31, 2016.

ATC

Investment in Transmission Affiliates

Schedule of significant transactions with ATC

The following table summarizes our significant related party transactions with ATC:

	Three Months Ended March 31
(in millions)	2018		2017
Charges to ATC for services and construction	$	4.6	$	4.2
Charges from ATC for network transmission services	84.5		87.3
Refund from ATC per FERC ROE order	—		28.3

Schedule of receivables and payables with ATC

Our balance sheets included the following receivables and payables related to ATC:

(in millions)	March 31, 2018		December 31, 2017
Accounts receivable
Services provided to ATC	$	1.8	$	1.5
Other current assets
Dividends receivable from ATC	—		39.9
Accounts payable
Services received from ATC	24.0		31.2

Schedule of summarized income statement data for ATC

Summarized financial data for ATC is included in the following tables:

	Three Months Ended March 31
(in millions)	2018		2017
Income statement data
Operating revenues	$	165.4	$	174.7
Operating expenses	84.9		82.7
Other expense, net	27.6		26.1
Net income	$	52.9	$	65.9

Schedule of summarized balance sheet data for ATC

(in millions)	March 31, 2018		December 31, 2017
Balance sheet data
Current assets	$	84.7	$	87.7
Noncurrent assets	4,681.7		4,598.9
Total assets	$	4,766.4	$	4,686.6
Current liabilities	$	473.3	$	767.2
Long-term debt	2,065.3		1,790.6
Other noncurrent liabilities	266.4		240.3
Shareholders' equity	1,961.4		1,888.5
Total liabilities and shareholders' equity	$	4,766.4	$	4,686.6

XML

SEGMENT INFORMATION (Tables)

3 Months Ended

Mar. 31, 2018

Segment Reporting [Abstract]

Financial information of reportable segments

The following tables show summarized financial information related to our reportable segments for the three months ended March 31, 2018 and 2017:

	Utility Operations
(in millions)	Wisconsin		Illinois		Other States		Total Utility Operations		Electric Transmission		Non-Utility Energy Infrastructure		Corporate and Other			Reconciling Eliminations			WEC Energy Group Consolidated
Three Months Ended
March 31, 2018
External revenues	$	1,589.1	$	507.3	$	169.9	$	2,266.3	$	—	$	18.8	$	1.4		$	—		$	2,286.5
Intersegment revenues	—		—		—		—		—		99.3		—			(99.3		)	—
Other operation and maintenance	468.5		112.2		26.6		607.3		—		1.7		(0.3		)	(96.8		)	511.9
Depreciation and amortization	135.1		40.9		6.6		182.6		—		18.3		7.7			—			208.6
Operating income (loss)	273.7		147.6		36.2		457.5		—		93.0		(5.4		)	—			545.1
Equity in earnings of transmission affiliates	—		—		—		—		32.8		—		—			—			32.8
Interest expense	49.4		12.3		2.1		63.8		—		16.1		28.0			(1.2		)	106.7

	Utility Operations
(in millions)	Wisconsin		Illinois		Other States		Total Utility Operations		Electric Transmission		Non-Utility Energy Infrastructure		Corporate and Other			Reconciling Eliminations			WEC Energy Group Consolidated
Three Months Ended
March 31, 2017
External revenues	$	1,612.1	$	525.3	$	157.9	$	2,295.3	$	—	$	6.3	$	2.9		$	—		$	2,304.5
Intersegment revenues	—		—		—		—		—		109.0		—			(109.0		)	—
Other operation and maintenance *	465.7		119.6		28.2		613.5		—		0.4		(0.4		)	(109.0		)	504.5
Depreciation and amortization	129.3		36.2		6.0		171.5		—		17.5		5.6			—			194.6
Operating income (loss) *	329.5		156.7		33.5		519.7		—		97.4		(2.4		)	—			614.7
Equity in earnings of transmission affiliates	—		—		—		—		41.9		—		—			—			41.9
Interest expense	48.7		11.1		2.3		62.1		—		15.3		29.1			(1.8		)	104.7

* Includes the retroactive restatement impacts of the implementation of ASU 2017-07. See Note 14, Employee Benefits, for more information on this new standard.

XML

COMMITMENTS AND CONTINGENCIES (Tables)

3 Months Ended

Mar. 31, 2018

Commitments and Contingencies Disclosure [Abstract]

Schedule of regulatory assets and reserves related to manufactured gas plant sites

We have established the following regulatory assets and reserves related to manufactured gas plant sites:

(in millions)	March 31, 2018		December 31, 2017
Regulatory assets	$	668.2	$	676.6
Reserves for future remediation	617.2		617.2

XML

SUPPLEMENTAL CASH FLOW INFORMATION (Tables)

3 Months Ended

Mar. 31, 2018

Additional Cash Flow Elements and Supplemental Cash Flow Information [Abstract]

Schedule of supplemental cash flow information

	Three Months Ended March 31
(in millions)	2018			2017
Cash (paid) for interest, net of amount capitalized	$	(68.5	)	$	(56.6	)
Cash received for income taxes, net	0.3			8.9
Significant non-cash transactions
Accounts payable related to construction costs	74.9			116.4
Portion of Bostco real estate holdings sale financed with note receivable *	—			7.0
Amortization of deferred revenue	6.3			6.2

* See Note 3, Disposition, for more information on this sale.

Reconciliation of cash and cash equivalents and restricted cash

See the following table for a reconciliation of cash and cash equivalents and restricted cash reported within the balance sheets to the sum of the total of the same amounts shown in the statements of cash flows at March 31.

(in millions)	2018		2017
Cash and cash equivalents	$	48.1	$	45.7
Restricted cash included in other current assets	—		0.8
Restricted cash included in other long term assets	23.6		26.9
Cash, cash equivalents, and restricted cash	$	71.7	$	73.4

Schedule of retroactively restated statements of cash flows

Our statements of cash flows for the years ended December 31, 2017, 2016, and 2015 were retroactively restated from what was previously presented in our 2017 Annual Report on Form 10-K to reflect the adoption of ASU 2016-18. The impacts to our statements of cash flows from adoption of this standard are reflected in the table below.

	Year Ended December 31, 2017									Year Ended December 31, 2016									Year Ended December 31, 2015
(in millions)	2017 Form 10-K Cash Flows			Impact of ASU 2016-18			Cash Flows After Adoption			2017 Form 10-K Cash Flows			Impact of ASU 2016-18			Cash Flows After Adoption			2017 Form 10-K Cash Flows			Impact of ASU 2016-18			Cash Flows After Adoption
Operating Activities
Change in –
Other current assets	$	(6.0	)	$	(1.1	)	$	(7.1	)	$	103.1		$	0.1		$	103.2		$	(27.2	)	$	—		$	(27.2	)
Other, net	(197.5		)	0.1			(197.4		)	(53.8		)	0.2			(53.6		)	(209.1		)	1.5			(207.6		)
Net cash provided by operating activities	2,079.6			(1.0		)	2,078.6			2,103.5			0.3			2,103.8			1,293.6			1.5			1,295.1
Investing Activities
Withdrawal of restricted cash from rabbi trust for qualifying payments	19.5			(19.5		)	—			26.6			(26.6		)	—			1.4			(1.4		)	—
Proceeds from the sale of investments held in rabbi trust	—			8.7			8.7			—			1.7			1.7			—			126.9			126.9
Purchase of investments held in rabbi trust	—			(3.7		)	(3.7		)	—			(59.2		)	(59.2		)	—			(60.2		)	(60.2		)
Integrys acquisition, net of cash acquired	—			—			—			—			—			—			(1,329.9		)	30.8			(1,299.1		)
Other, net	12.0			—			12.0			3.0			—			3.0			57.0			(1.2		)	55.8
Net cash used in investing activities	(2,239.6		)	(14.5		)	(2,254.1		)	(1,270.1		)	(84.1		)	(1,354.2		)	(2,517.5		)	94.9			(2,422.6		)
Financing Activities
Other, net	(6.5		)	—			(6.5		)	(13.6		)	—			(13.6		)	(18.9		)	22.6			3.7
Net cash provided by (used in) financing activities	161.4			—			161.4			(845.7		)	—			(845.7		)	1,211.8			22.6			1,234.4
Net change in cash, cash equivalents, and restricted cash	1.4			(15.5		)	(14.1		)	(12.3		)	(83.8		)	(96.1		)	(12.1		)	119.0			106.9
Cash, cash equivalents, and restricted cash at beginning of period	37.5			35.2			72.7			49.8			119.0			168.8			61.9			—			61.9
Cash, cash equivalents, and restricted cash at end of period	$	38.9		$	19.7		$	58.6		$	37.5		$	35.2		$	72.7		$	49.8		$	119.0		$	168.8

XML

GENERAL INFORMATION - GENERAL (Details) customer in Millions	Mar. 31, 2018 customer
Electric
Product information [Line Items]
Number Of Customers	1.6
Natural gas
Product information [Line Items]
Number Of Customers	2.9
ATC
Product information [Line Items]
Equity method investment, ownership interest (as a percent)	60.00%

XML

ACQUISITIONS - FORWARD ACQUISITION (Details) - Forward Wind Energy Center $ in Millions	1 Months Ended
	Apr. 30, 2018 USD ($) utility	Apr. 02, 2018 wind_turbines MW	Mar. 31, 2018
WPS
Business Acquisition [Line Items]
Percentage of Forward Wind Energy Center's output purchased by WPS			44.60%
Subsequent event
Business Acquisition [Line Items]
Number of wind turbines at Forward Wind Energy Center | wind_turbines		86
Capacity of Foward Wind Energy Center | MW		129
Purchase price	$ 173.9
Subsequent event | WPS
Business Acquisition [Line Items]
Number of utilities along with WPS that entered in an agreement to purchase Forward Wind Energy Center | utility	2
Purchase price	$ 77.6
WPS's share of Forward Wind Energy Center's purchase price	44.60%

XML

ACQUISITIONS - BLUEWATER ACQUISITION - CONSIDERATION TRANSFERRED (Details) - Bluewater - USD ($) $ in Millions	1 Months Ended
	Jun. 30, 2017	Mar. 31, 2018
Business Acquisition [Line Items]
Purchase price	$ 226.0
Percentage of current storage needs provided		33.00%
Acquisition related costs	$ 4.9

XML

ACQUISITIONS- BLUEWATER ACQUISITION - PURCHASE PRICE ALLOCATION (Details) - Bluewater $ in Millions	1 Months Ended
	Jun. 30, 2017 USD ($)
Business Acquisition [Line Items]
Current assets	$ 2.0
Net property, plant, and equipment	218.3
Goodwill	6.6
Current liabilities	(0.9)
Total purchase price	$ 226.0

XML

ACQUISITIONS - UPSTREAM ACQUISITION (Details) - Upstream - Subsequent event $ in Millions	1 Months Ended
	Apr. 30, 2018 USD ($) MW
Business Acquisition [Line Items]
WEC's ownership interest in Upstream Wind Energy Center	80.00%
Capacity of Upstream Wind Energy Center | MW	202.5
Acquisition purchase price | $	$ 276.0
Number of years Upstream will receive fixed payment	10 years
Federal production tax credit percent of published rate	100.00%

XML

OPERATING REVENUES - DISAGGREGATION OF OPERATING REVENUES (Details) $ in Millions	3 Months Ended
	Mar. 31, 2018 USD ($) contract performance_obligations	Mar. 31, 2017 USD ($)
Disaggregation of Operating Revenues
Revenues	$ 2,286.5	$ 2,304.5
Revenues from contracts with customers
Disaggregation of Operating Revenues
Revenues	2,290.0
Other operating revenues
Disaggregation of Operating Revenues
Revenues	$ (3.5)
Electric
Disaggregation of Operating Revenues
Number of contracts | contract	1
Number of performance obligations | performance_obligations	2
Number of days payment is due	30 days
Electric | Revenues from contracts with customers
Disaggregation of Operating Revenues
Revenues	$ 1,067.7
Natural gas
Disaggregation of Operating Revenues
Number of days payment is due	30 days
Natural gas | Revenues from contracts with customers
Disaggregation of Operating Revenues
Revenues	$ 1,210.7
Natural gas | Transferred over time | Revenues from contracts with customers
Disaggregation of Operating Revenues
Revenues	1,198.3
Natural gas | Transferred over time | Revenues from contracts with customers | Residential
Disaggregation of Operating Revenues
Revenues	812.5
Natural gas | Transferred over time | Revenues from contracts with customers | Total retail
Disaggregation of Operating Revenues
Revenues	1,174.5
Natural gas | Transferred over time | Revenues from contracts with customers | Commercial and industrial
Disaggregation of Operating Revenues
Revenues	362.0
Natural gas | Transferred over time | Revenues from contracts with customers | Transport
Disaggregation of Operating Revenues
Revenues	108.6
Natural gas | Transferred over time | Revenues from contracts with customers | Other utility
Disaggregation of Operating Revenues
Revenues	(84.8)
Total utility revenues | Revenues from contracts with customers
Disaggregation of Operating Revenues
Revenues	2,278.4
Other non-utility revenues | Revenues from contracts with customers
Disaggregation of Operating Revenues
Revenues	11.6
Public Utility
Disaggregation of Operating Revenues
Revenues	2,266.3
Public Utility | Other operating revenues
Disaggregation of Operating Revenues
Revenues	(3.6)
Public Utility | Transferred over time | Revenues from contracts with customers
Disaggregation of Operating Revenues
Revenues	2,269.9
Public Utility | Electric | Transferred over time | Revenues from contracts with customers
Disaggregation of Operating Revenues
Revenues	1,067.7
Public Utility | Natural gas | Transferred over time | Revenues from contracts with customers
Disaggregation of Operating Revenues
Revenues	1,198.3
Public Utility | Total utility revenues | Transferred over time | Revenues from contracts with customers
Disaggregation of Operating Revenues
Revenues	2,266.0
Public Utility | Other non-utility revenues | Transferred over time | Revenues from contracts with customers
Disaggregation of Operating Revenues
Revenues	3.9
Wisconsin | Natural gas | Transferred over time | Revenues from contracts with customers
Disaggregation of Operating Revenues
Revenues	518.0
Wisconsin | Natural gas | Transferred over time | Revenues from contracts with customers | Residential
Disaggregation of Operating Revenues
Revenues	356.7
Wisconsin | Natural gas | Transferred over time | Revenues from contracts with customers | Total retail
Disaggregation of Operating Revenues
Revenues	544.6
Wisconsin | Natural gas | Transferred over time | Revenues from contracts with customers | Commercial and industrial
Disaggregation of Operating Revenues
Revenues	187.9
Wisconsin | Natural gas | Transferred over time | Revenues from contracts with customers | Transport
Disaggregation of Operating Revenues
Revenues	21.0
Wisconsin | Natural gas | Transferred over time | Revenues from contracts with customers | Other utility
Disaggregation of Operating Revenues
Revenues	(47.6)
Wisconsin | Public Utility
Disaggregation of Operating Revenues
Revenues	1,589.1
Wisconsin | Public Utility | Other operating revenues
Disaggregation of Operating Revenues
Revenues	3.4
Wisconsin | Public Utility | Transferred over time | Revenues from contracts with customers
Disaggregation of Operating Revenues
Revenues	1,585.7
Wisconsin | Public Utility | Electric | Transferred over time | Revenues from contracts with customers
Disaggregation of Operating Revenues
Revenues	1,067.7
Wisconsin | Public Utility | Electric | Transferred over time | Revenues from contracts with customers | Residential
Disaggregation of Operating Revenues
Revenues	384.3
Wisconsin | Public Utility | Electric | Transferred over time | Revenues from contracts with customers | Small commercial and industrial
Disaggregation of Operating Revenues
Revenues	330.7
Wisconsin | Public Utility | Electric | Transferred over time | Revenues from contracts with customers | Large commercial and industrial
Disaggregation of Operating Revenues
Revenues	203.9
Wisconsin | Public Utility | Electric | Transferred over time | Revenues from contracts with customers | Other
Disaggregation of Operating Revenues
Revenues	7.7
Wisconsin | Public Utility | Electric | Transferred over time | Revenues from contracts with customers | Total retail
Disaggregation of Operating Revenues
Revenues	926.6
Wisconsin | Public Utility | Electric | Transferred over time | Revenues from contracts with customers | Wholesale
Disaggregation of Operating Revenues
Revenues	54.9
Wisconsin | Public Utility | Electric | Transferred over time | Revenues from contracts with customers | Resale
Disaggregation of Operating Revenues
Revenues	73.8
Wisconsin | Public Utility | Electric | Transferred over time | Revenues from contracts with customers | Steam
Disaggregation of Operating Revenues
Revenues	9.7
Wisconsin | Public Utility | Electric | Transferred over time | Revenues from contracts with customers | Other utility
Disaggregation of Operating Revenues
Revenues	2.7
Wisconsin | Public Utility | Natural gas | Transferred over time | Revenues from contracts with customers
Disaggregation of Operating Revenues
Revenues	518.0
Wisconsin | Public Utility | Total utility revenues | Transferred over time | Revenues from contracts with customers
Disaggregation of Operating Revenues
Revenues	1,585.7
Wisconsin | Public Utility | Other non-utility revenues | Transferred over time | Revenues from contracts with customers
Disaggregation of Operating Revenues
Revenues	0.0
Illinois | Natural gas | Transferred over time | Revenues from contracts with customers
Disaggregation of Operating Revenues
Revenues	507.6
Illinois | Natural gas | Transferred over time | Revenues from contracts with customers | Residential
Disaggregation of Operating Revenues
Revenues	332.6
Illinois | Natural gas | Transferred over time | Revenues from contracts with customers | Total retail
Disaggregation of Operating Revenues
Revenues	442.0
Illinois | Natural gas | Transferred over time | Revenues from contracts with customers | Commercial and industrial
Disaggregation of Operating Revenues
Revenues	109.4
Illinois | Natural gas | Transferred over time | Revenues from contracts with customers | Transport
Disaggregation of Operating Revenues
Revenues	77.7
Illinois | Natural gas | Transferred over time | Revenues from contracts with customers | Other utility
Disaggregation of Operating Revenues
Revenues	(12.1)
Illinois | Public Utility
Disaggregation of Operating Revenues
Revenues	507.3
Illinois | Public Utility | Other operating revenues
Disaggregation of Operating Revenues
Revenues	(0.3)
Illinois | Public Utility | Transferred over time | Revenues from contracts with customers
Disaggregation of Operating Revenues
Revenues	507.6
Illinois | Public Utility | Electric | Transferred over time | Revenues from contracts with customers
Disaggregation of Operating Revenues
Revenues	0.0
Illinois | Public Utility | Natural gas | Transferred over time | Revenues from contracts with customers
Disaggregation of Operating Revenues
Revenues	507.6
Illinois | Public Utility | Total utility revenues | Transferred over time | Revenues from contracts with customers
Disaggregation of Operating Revenues
Revenues	507.6
Illinois | Public Utility | Other non-utility revenues | Transferred over time | Revenues from contracts with customers
Disaggregation of Operating Revenues
Revenues	0.0
Other States | Natural gas | Transferred over time | Revenues from contracts with customers
Disaggregation of Operating Revenues
Revenues	172.7
Other States | Natural gas | Transferred over time | Revenues from contracts with customers | Residential
Disaggregation of Operating Revenues
Revenues	123.2
Other States | Natural gas | Transferred over time | Revenues from contracts with customers | Total retail
Disaggregation of Operating Revenues
Revenues	187.9
Other States | Natural gas | Transferred over time | Revenues from contracts with customers | Commercial and industrial
Disaggregation of Operating Revenues
Revenues	64.7
Other States | Natural gas | Transferred over time | Revenues from contracts with customers | Transport
Disaggregation of Operating Revenues
Revenues	9.9
Other States | Natural gas | Transferred over time | Revenues from contracts with customers | Other utility
Disaggregation of Operating Revenues
Revenues	(25.1)
Other States | Public Utility
Disaggregation of Operating Revenues
Revenues	169.9
Other States | Public Utility | Other operating revenues
Disaggregation of Operating Revenues
Revenues	(6.7)
Other States | Public Utility | Transferred over time | Revenues from contracts with customers
Disaggregation of Operating Revenues
Revenues	176.6
Other States | Public Utility | Electric | Transferred over time | Revenues from contracts with customers
Disaggregation of Operating Revenues
Revenues	0.0
Other States | Public Utility | Natural gas | Transferred over time | Revenues from contracts with customers
Disaggregation of Operating Revenues
Revenues	172.7
Other States | Public Utility | Total utility revenues | Transferred over time | Revenues from contracts with customers
Disaggregation of Operating Revenues
Revenues	172.7
Other States | Public Utility | Other non-utility revenues | Transferred over time | Revenues from contracts with customers
Disaggregation of Operating Revenues
Revenues	3.9
Electric Transmission
Disaggregation of Operating Revenues
Revenues	0.0
Electric Transmission | Revenues from contracts with customers
Disaggregation of Operating Revenues
Revenues	0.0
Electric Transmission | Other operating revenues
Disaggregation of Operating Revenues
Revenues	0.0
Electric Transmission | Electric | Revenues from contracts with customers
Disaggregation of Operating Revenues
Revenues	0.0
Electric Transmission | Natural gas | Revenues from contracts with customers
Disaggregation of Operating Revenues
Revenues	0.0
Electric Transmission | Total utility revenues | Revenues from contracts with customers
Disaggregation of Operating Revenues
Revenues	0.0
Electric Transmission | Other non-utility revenues | Revenues from contracts with customers
Disaggregation of Operating Revenues
Revenues	0.0
Non-Utility Energy Infrastructure
Disaggregation of Operating Revenues
Revenues	118.1
Non-Utility Energy Infrastructure | Revenues from contracts with customers
Disaggregation of Operating Revenues
Revenues	22.0
Non-Utility Energy Infrastructure | Other operating revenues
Disaggregation of Operating Revenues
Revenues	96.1
Non-Utility Energy Infrastructure | Electric | Revenues from contracts with customers
Disaggregation of Operating Revenues
Revenues	0.0
Non-Utility Energy Infrastructure | Natural gas | Revenues from contracts with customers
Disaggregation of Operating Revenues
Revenues	14.9
Non-Utility Energy Infrastructure | Total utility revenues | Revenues from contracts with customers
Disaggregation of Operating Revenues
Revenues	14.9
Non-Utility Energy Infrastructure | Other non-utility revenues | Revenues from contracts with customers
Disaggregation of Operating Revenues
Revenues	7.1
Corporate and Other
Disaggregation of Operating Revenues
Revenues	1.4
Corporate and Other | Revenues from contracts with customers
Disaggregation of Operating Revenues
Revenues	1.3
Corporate and Other | Other operating revenues
Disaggregation of Operating Revenues
Revenues	0.1
Corporate and Other | Electric | Revenues from contracts with customers
Disaggregation of Operating Revenues
Revenues	0.0
Corporate and Other | Natural gas | Revenues from contracts with customers
Disaggregation of Operating Revenues
Revenues	0.0
Corporate and Other | Total utility revenues | Revenues from contracts with customers
Disaggregation of Operating Revenues
Revenues	0.0
Corporate and Other | Other non-utility revenues | Revenues from contracts with customers
Disaggregation of Operating Revenues
Revenues	1.3
Reconciling Eliminations
Disaggregation of Operating Revenues
Revenues	(99.3)
Reconciling Eliminations | Revenues from contracts with customers
Disaggregation of Operating Revenues
Revenues	(3.2)
Reconciling Eliminations | Other operating revenues
Disaggregation of Operating Revenues
Revenues	(96.1)
Reconciling Eliminations | Electric | Revenues from contracts with customers
Disaggregation of Operating Revenues
Revenues	0.0
Reconciling Eliminations | Natural gas | Revenues from contracts with customers
Disaggregation of Operating Revenues
Revenues	(2.5)
Reconciling Eliminations | Total utility revenues | Revenues from contracts with customers
Disaggregation of Operating Revenues
Revenues	(2.5)
Reconciling Eliminations | Other non-utility revenues | Revenues from contracts with customers
Disaggregation of Operating Revenues
Revenues	$ (0.7)

XML

OPERATING REVENUES - OTHER NON-UTILITY OPERATING REVENUES (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Disaggregation of Operating Revenues
Revenues	$ 2,286.5	$ 2,304.5
We Power revenues
Disaggregation of Operating Revenues
Revenue amortized from deferred revenue during the period	$ 6.4
Appliance service repairs | Maximum
Disaggregation of Operating Revenues
Duration of contract for remaining performance obligations in contract	1 year
Revenues from contracts with customers
Disaggregation of Operating Revenues
Revenues	$ 2,290.0
Other non-utility revenues | Revenues from contracts with customers
Disaggregation of Operating Revenues
Revenues	11.6
Other non-utility revenues | Revenues from contracts with customers | We Power revenues
Disaggregation of Operating Revenues
Revenues	6.4
Other non-utility revenues | Revenues from contracts with customers | Distributed renewable solar project revenues
Disaggregation of Operating Revenues
Revenues	1.3
Transferred over time | Other non-utility revenues | Revenues from contracts with customers | Appliance service repairs
Disaggregation of Operating Revenues
Revenues	$ 3.9

XML

OPERATING REVENUES - OTHER OPERATING REVENUES (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Disaggregation of Operating Revenues
Revenues	$ 2,286.5	$ 2,304.5
Other operating revenues
Disaggregation of Operating Revenues
Revenues	(3.5)
Other operating revenues | Alternative revenues
Disaggregation of Operating Revenues
Revenues	(16.1)
Other operating revenues | Late payment charges
Disaggregation of Operating Revenues
Revenues	11.4
Other operating revenues | Leases
Disaggregation of Operating Revenues
Revenues	$ 1.2

XML

PROPERTY, PLANT, AND EQUIPMENT (Details) $ in Millions	1 Months Ended	12 Months Ended
	Oct. 31, 2017 MW	Dec. 31, 2017 USD ($)	Mar. 31, 2018 USD ($)
Edgewater Unit 4
Property, plant, and equipment
Plant to be retired, net			$ 12.7
Pleasant Prairie power plant
Property, plant, and equipment
Plant to be retired, net			674.1
Presque Isle power plant
Property, plant, and equipment
Plant to be retired, net			188.7
Pulliam power plant
Property, plant, and equipment
Plant to be retired, net			$ 43.6
UMERC
Property, plant, and equipment
Capacity of natural gas-fired generation facility (in megawatts) | MW	180
Wisconsin
Property, plant, and equipment
Severance expense		$ 29.4

XML

COMMON EQUITY - STOCK-BASED COMPENSATION AWARDS GRANTED (Details)	3 Months Ended
	Mar. 31, 2018 $ / shares shares
Stock options
Stock-based Compensation
Stock options granted | shares	710,710
Stock options granted, weighted average exercise price | $ / shares	$ 65.60
Stock options granted, weighted-average grant date fair value | $ / shares	$ 7.71
Restricted shares
Stock-based Compensation
Awards granted | shares	156,340
Restricted shares granted, weighted-average grant date fair value | $ / shares	$ 64.20
Performance units
Stock-based Compensation
Awards granted | shares	217,560

XML

COMMON EQUITY - COMMON STOCK DIVIDENDS (Details) - $ / shares		3 Months Ended
	Apr. 19, 2018	Mar. 31, 2018	Mar. 31, 2017
Dividends Payable
Quarterly cash dividend declared (in dollars per share)		$ 0.5525	$ 0.5200
Subsequent event
Dividends Payable
Quarterly cash dividend declared (in dollars per share)	$ 0.5525

XML

SHORT-TERM DEBT AND LINES OF CREDIT - SHORT-TERM BORROWINGS (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2018	Dec. 31, 2017
Short-term borrowings
Commercial paper outstanding	$ 1,200.3	$ 1,444.6
Commercial paper
Short-term borrowings
Weighted-average interest rate on amounts outstanding	2.24%	1.77%
Average amount outstanding during the period	$ 1,254.4
Weighted-average interest rate during the period	1.90%

XML

SHORT-TERM DEBT AND LINES OF CREDIT - REVOLVING CREDIT FACILITIES (Details) - USD ($) $ in Millions	Mar. 31, 2018	Dec. 31, 2017
Revolving credit facilities
Short-term credit capacity	$ 2,800.0
Letters of credit issued inside credit facilities	1.2
Commercial paper outstanding	1,200.3	$ 1,444.6
Available capacity under existing agreements	1,598.5
WEC Energy Group | Credit facility maturing during October 2022
Revolving credit facilities
Short-term credit capacity	1,200.0
WE | Credit facility maturing during October 2022
Revolving credit facilities
Short-term credit capacity	500.0
WPS | Credit facility maturing during October 2022
Revolving credit facilities
Short-term credit capacity	400.0
WG | Credit facility maturing during October 2022
Revolving credit facilities
Short-term credit capacity	350.0
PGL | Credit facility maturing during October 2022
Revolving credit facilities
Short-term credit capacity	$ 350.0

XML

LONG TERM DEBT (Details) - Integrys Holding - Integrys Junior Notes due 2066 - USD ($) $ in Millions	May 14, 2018	Mar. 31, 2018
Debt Instrument [Line Items]
Long-term debt, current portion		$ 114.9
Subsequent event
Debt Instrument [Line Items]
Extinguishment of debt	$ 114.9

XML

MATERIALS, SUPPLIES, AND INVENTORIES (Details) - USD ($) $ in Millions	Mar. 31, 2018	Dec. 31, 2017
Inventory Disclosure [Abstract]
Natural gas in storage	$ 34.8	$ 209.0
Materials and supplies	213.7	211.2
Fossil fuel	127.5	118.8
Total	376.0	$ 539.0
LIFO cost method
LIFO liquidation balance	$ 35.6

XML

INCOME TAXES (Details) - USD ($) $ in Millions	1 Months Ended	3 Months Ended
	Dec. 31, 2017	Mar. 31, 2018	Mar. 31, 2017
Effective Income Tax Rate Reconciliation, Amount
Statutory federal income tax, amount		$ 100.5
State income taxes net of federal tax benefit, amount		29.9
Federal tax reform, amount		(15.5)
Tax repairs, amount		(25.5)
Other, amount		(1.1)
Total income tax expense, amount		$ 88.3	$ 213.3
Effective Income Tax Rate Reconciliation, Percent
Statutory federal income tax, percentage		21.00%	35.00%
State income taxes net of federal tax benefit, percentage		6.20%
Federal tax reform, percentage		(3.20%)
Tax repairs, percentage		(5.30%)
Other, percentage		(0.30%)
Total income tax expense, percentage		18.40%
Measurement period to complete accounting related to Tax Cuts and Jobs Act	1 year

XML

FAIR VALUE MEASUREMENTS - ASSETS AND LIABILITIES MEASURED ON A RECURRING BASIS (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017	Dec. 31, 2017
Assets
Derivative asset	$ 5.4		$ 12.4
Liabilities
Derivative liability	5.1		11.6
Fair value measurements on a recurring basis
Assets
Derivative asset	5.4		12.4
Investments held in rabbi trust	103.6		120.7
Liabilities
Derivative liability	5.1		11.6
Net Unrealized Gain (Loss) on Investments
Net unrealized gains (losses) included in earnings related to investments held in rabbi trust	(3.1)	$ 5.2
Fair value measurements on a recurring basis | Level 1
Assets
Derivative asset	2.3		3.0
Investments held in rabbi trust	103.6		120.7
Liabilities
Derivative liability	3.4		7.0
Fair value measurements on a recurring basis | Level 2
Assets
Derivative asset	1.6		5.0
Investments held in rabbi trust	0.0		0.0
Liabilities
Derivative liability	1.7		4.6
Fair value measurements on a recurring basis | Level 3
Assets
Derivative asset	1.5		4.4
Investments held in rabbi trust	0.0		0.0
Liabilities
Derivative liability	0.0		0.0
Fair value measurements on a recurring basis | Natural gas contracts
Assets
Derivative asset	2.2		5.7
Liabilities
Derivative liability	4.8		10.8
Fair value measurements on a recurring basis | Natural gas contracts | Level 1
Assets
Derivative asset	1.7		1.8
Liabilities
Derivative liability	3.4		7.0
Fair value measurements on a recurring basis | Natural gas contracts | Level 2
Assets
Derivative asset	0.5		3.9
Liabilities
Derivative liability	1.4		3.8
Fair value measurements on a recurring basis | Natural gas contracts | Level 3
Assets
Derivative asset	0.0		0.0
Liabilities
Derivative liability	0.0		0.0
Fair value measurements on a recurring basis | Petroleum products contracts
Assets
Derivative asset	0.6		1.2
Fair value measurements on a recurring basis | Petroleum products contracts | Level 1
Assets
Derivative asset	0.6		1.2
Fair value measurements on a recurring basis | Petroleum products contracts | Level 2
Assets
Derivative asset	0.0		0.0
Fair value measurements on a recurring basis | Petroleum products contracts | Level 3
Assets
Derivative asset	0.0		0.0
Fair value measurements on a recurring basis | FTRs
Assets
Derivative asset	1.5		4.4
Fair value measurements on a recurring basis | FTRs | Level 1
Assets
Derivative asset	0.0		0.0
Fair value measurements on a recurring basis | FTRs | Level 2
Assets
Derivative asset	0.0		0.0
Fair value measurements on a recurring basis | FTRs | Level 3
Assets
Derivative asset	1.5		4.4
Fair value measurements on a recurring basis | Coal contracts
Assets
Derivative asset	1.1		1.1
Liabilities
Derivative liability	0.3		0.8
Fair value measurements on a recurring basis | Coal contracts | Level 1
Assets
Derivative asset	0.0		0.0
Liabilities
Derivative liability	0.0		0.0
Fair value measurements on a recurring basis | Coal contracts | Level 2
Assets
Derivative asset	1.1		1.1
Liabilities
Derivative liability	0.3		0.8
Fair value measurements on a recurring basis | Coal contracts | Level 3
Assets
Derivative asset	0.0		0.0
Liabilities
Derivative liability	$ 0.0		$ 0.0

XML

FAIR VALUE MEASUREMENTS - LEVEL 3 RECONCILIATION (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Fair Value, Assets and Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Abstract]
Balance at the beginning of the period	$ 4.4	$ 5.1
Settlements	(2.9)	(3.4)
Balance at the end of period	$ 1.5	$ 1.7

XML

FAIR VALUE MEASUREMENTS - FINANCIAL INSTRUMENTS (Details) - USD ($) $ in Millions	Mar. 31, 2018	Dec. 31, 2017
Financial Instruments
Preferred stock	$ 30.4	$ 30.4
Carrying Amount
Financial Instruments
Preferred stock	30.4	30.4
Long-term debt, including current portion	9,549.3	9,561.7
Capital lease obligations	26.1	27.0
Fair Value
Financial Instruments
Preferred stock	29.1	30.5
Long-term debt, including current portion	$ 10,054.5	$ 10,341.9

XML

DERIVATIVE INSTRUMENTS - DERIVATIVE ASSETS AND LIABILITIES (Details) - USD ($) $ in Millions	Mar. 31, 2018	Dec. 31, 2017
Derivative Asset
Other current derivative assets	$ 5.1	$ 11.8
Other long-term derivative assets	0.3	0.6
Derivative asset	5.4	12.4
Derivative Liability
Other current derivative liabilities	4.0	10.0
Other long-term derivative liabilities	1.1	1.6
Derivative liability	5.1	11.6
Natural gas contracts
Derivative Asset
Other current derivative assets	2.2	5.6
Other long-term derivative assets	0.0	0.1
Derivative Liability
Other current derivative liabilities	3.7	9.4
Other long-term derivative liabilities	1.1	1.4
Petroleum products contracts
Derivative Asset
Other current derivative assets	0.6	1.2
Derivative Liability
Other current derivative liabilities	0.0	0.0
FTRs
Derivative Asset
Other current derivative assets	1.5	4.4
Derivative Liability
Other current derivative liabilities	0.0	0.0
Coal contracts
Derivative Asset
Other current derivative assets	0.8	0.6
Other long-term derivative assets	0.3	0.5
Derivative Liability
Other current derivative liabilities	0.3	0.6
Other long-term derivative liabilities	$ 0.0	$ 0.2

XML

DERIVATIVE INSTRUMENTS - GAINS (LOSSES) AND NOTIONAL VOLUMES (Details) gal in Millions, MWh in Millions, MMBTU in Millions, $ in Millions	3 Months Ended
	Mar. 31, 2018 USD ($) MMBTU MWh gal	Mar. 31, 2017 USD ($) MMBTU MWh gal
Realized Gain (Loss) on Derivatives, Net
Gains (Losses)	$ (1.0)	$ 2.2
Natural gas contracts
Realized Gain (Loss) on Derivatives, Net
Gains (Losses)	$ (5.2)	$ (0.3)
Notional Sales Volumes
Notional sales volumes | MMBTU	48.1	34.1
Petroleum products contracts
Realized Gain (Loss) on Derivatives, Net
Gains (Losses)	$ 0.5	$ (0.5)
Notional Sales Volumes
Notional sales volumes (gallons) | gal	2.1	4.9
FTRs
Realized Gain (Loss) on Derivatives, Net
Gains (Losses)	$ 3.7	$ 3.0
Notional Sales Volumes
Notional sales volumes | MWh	8.2	9.2

XML

DERIVATIVE INSTRUMENTS - BALANCE SHEET OFFSETTING (Details) - USD ($) $ in Millions	Mar. 31, 2018	Dec. 31, 2017
Cash collateral
Cash collateral in margin account	$ 11.8	$ 16.2
Offsetting Derivative Assets
Gross amount recognized on the balance sheet	5.4	12.4
Gross amount not offset on the balance sheet	(2.1)	(4.9)
Net amount	3.3	7.5
Offsetting Derivative Liabilities
Gross amount recognized on the balance sheet	5.1	11.6
Gross amount not offset on the balance sheet	(3.7)	(9.0)
Net amount	1.4	2.6
Collateral posted	1.6	4.1
Credit Risk Related Contingent Features
Aggregate fair value of all derivative instruments with specific credit risk-related contingent fearures in a net liability position	1.1	3.7
Additional collateral that would have been required	$ 1.5	$ 2.7

XML

GUARANTEES (Details) $ in Millions	Mar. 31, 2018 USD ($)
Guarantees
Total guarantees	$ 100.4
Guarantees expiring in less than 1 year	64.3
Guarantees expiring within 1 to 3 years	25.5
Guarantees with expiration over 3 years	10.6
Commodity transactions guarantee
Guarantees
Total guarantees	8.1
Guarantees expiring in less than 1 year	8.1
Guarantees expiring within 1 to 3 years	0.0
Guarantees with expiration over 3 years	0.0
Standby letters of credit
Guarantees
Total guarantees	71.4
Guarantees expiring in less than 1 year	46.0
Guarantees expiring within 1 to 3 years	25.4
Guarantees with expiration over 3 years	0.0
Surety bonds
Guarantees
Total guarantees	9.8
Guarantees expiring in less than 1 year	9.7
Guarantees expiring within 1 to 3 years	0.1
Guarantees with expiration over 3 years	0.0
Other guarantees
Guarantees
Total guarantees	11.1
Guarantees expiring in less than 1 year	0.5
Guarantees expiring within 1 to 3 years	0.0
Guarantees with expiration over 3 years	10.6
Other indemnifications
Guarantees
Total guarantees	11.1
Liability related to workers compensation coverage	10.6
Non-Utility Energy Infrastructure | Commodity transactions guarantee
Guarantees
Total guarantees	$ 8.1

XML

EMPLOYEE BENEFITS-COSTS AND CONTRIBUTIONS (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Components of net periodic benefit cost
Contributions and payments related to pension and OPEB plans	$ 5.3	$ 106.0
Pension Costs
Components of net periodic benefit cost
Service cost	12.0	11.7
Interest cost	28.3	31.2
Expected return on plan assets	(49.6)	(49.6)
Loss on plan settlement	0.4	0.0
Amortization of prior service cost (credit)	0.7	0.7
Amortization of net actuarial loss	23.1	21.9
Net periodic benefit (credit) cost	14.9	15.9
Contributions and payments related to pension and OPEB plans	3.7
Estimated future employer contributions for the remainder of the year	8.5
Other Postretirement Benefit Costs
Components of net periodic benefit cost
Service cost	6.2	6.3
Interest cost	7.5	8.5
Expected return on plan assets	(14.9)	(13.7)
Amortization of prior service cost (credit)	(3.8)	(2.8)
Amortization of net actuarial loss	0.3	1.5
Net periodic benefit (credit) cost	(4.7)	$ (0.2)
Contributions and payments related to pension and OPEB plans	1.6
Estimated future employer contributions for the remainder of the year	$ 7.9

XML

EMPLOYEE BENEFITS-IMPACT OF ADOPTION OF ASU 2017-07 (Details) - USD ($) $ in Millions	3 Months Ended		12 Months Ended
	Mar. 31, 2018	Mar. 31, 2017	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Other operation and maintenance	$ 511.9	$ 504.5	$ 2,056.1	$ 2,171.3	$ 1,710.7
Other income, net	7.5	18.3	73.7	66.6	60.3
2017 Form 10-K Income Statement
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Other operation and maintenance			2,047.0	2,185.5	1,709.3
Other income, net			64.6	80.8	58.9
Accounting Standards Update 2017-07
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Non-service cost components of net benefit cost	$ (7.2)
Accounting Standards Update 2017-07 | Impact of ASU 2017-07
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Non-service cost components of net benefit cost		$ (2.6)
Other operation and maintenance			9.1	(14.2)	1.4
Other income, net			$ 9.1	$ (14.2)	$ 1.4

XML

GOODWILL (Details) $ in Millions	3 Months Ended
	Mar. 31, 2018 USD ($)
Changes to our goodwill balances by segment
Goodwill balance as of January 1, 2018	$ 3,053.5
Goodwill balance as of March 31, 2018	3,052.8
Accumulated impairment losses	0.0
Bluewater
Changes to our goodwill balances by segment
Adjustment to Bluewater purchase price allocation	(0.7)
Wisconsin
Changes to our goodwill balances by segment
Goodwill balance as of January 1, 2018	2,104.3
Goodwill balance as of March 31, 2018	2,104.3
Wisconsin | Bluewater
Changes to our goodwill balances by segment
Adjustment to Bluewater purchase price allocation	0.0
Illinois
Changes to our goodwill balances by segment
Goodwill balance as of January 1, 2018	758.7
Goodwill balance as of March 31, 2018	758.7
Illinois | Bluewater
Changes to our goodwill balances by segment
Adjustment to Bluewater purchase price allocation	0.0
Other States
Changes to our goodwill balances by segment
Goodwill balance as of January 1, 2018	183.2
Goodwill balance as of March 31, 2018	183.2
Other States | Bluewater
Changes to our goodwill balances by segment
Adjustment to Bluewater purchase price allocation	0.0
Non-Utility Energy Infrastructure
Changes to our goodwill balances by segment
Goodwill balance as of January 1, 2018	7.3
Goodwill balance as of March 31, 2018	6.6
Non-Utility Energy Infrastructure | Bluewater
Changes to our goodwill balances by segment
Adjustment to Bluewater purchase price allocation	$ (0.7)

XML

INVESTMENT IN TRANSMISSION AFFILIATES - CHANGES TO INVESTMENT (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017	Dec. 31, 2017	Dec. 31, 2016
Changes to investment in Transmission Affiliates
Investment in Transmission Affiliates, balance at beginning of period	$ 1,553.4	$ 1,443.9
Add: Earnings (loss) from equity method investment	32.8	41.9
Add: Capital contributions	12.8	27.6
Less: Other	0.1	0.1
Investment in Transmission Affiliates, balance at end of period	$ 1,598.9	1,513.3
ATC
Investment in Transmission Affiliates
Equity method investment, ownership interest (as a percent)	60.00%
Changes to investment in Transmission Affiliates
Investment in Transmission Affiliates, balance at beginning of period	$ 1,515.8	1,443.9
Add: Earnings (loss) from equity method investment	33.4	47.7
Add: Capital contributions	12.0	24.1
Less: Other	0.1	0.1
Investment in Transmission Affiliates, balance at end of period	1,561.1	1,515.6
Dividends receivable from ATC	$ 0.0		$ 39.9	$ 35.2
ATC Holdco
Investment in Transmission Affiliates
Equity method investment, ownership interest (as a percent)	75.00%
Changes to investment in Transmission Affiliates
Investment in Transmission Affiliates, balance at beginning of period	$ 37.6	0.0
Add: Earnings (loss) from equity method investment	(0.6)	(5.8)
Add: Capital contributions	0.8	3.5
Less: Other	0.0	0.0
Investment in Transmission Affiliates, balance at end of period	$ 37.8	$ (2.3)

XML

INVESTMENT IN TRANSMISSION AFFILIATES - RELATED PARTY TRANSACTIONS (Details) - ATC - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Investment in Transmission Affiliates
Charges to ATC for services and construction	$ 4.6	$ 4.2
Charges from ATC for network transmission services	84.5	87.3
Refund from ATC per FERC ROE order	$ 0.0	$ 28.3

XML

INVESTMENT IN TRANSMISSION AFFILIATES - RELATED PARTY TRANSACTIONS BALANCE SHEET INFORMATION (Details) - ATC - USD ($) $ in Millions	Mar. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Investment in Transmission Affiliates
Accounts receivable for services provided to ATC	$ 1.8	$ 1.5
Dividends receivable from ATC	0.0	39.9	$ 35.2
Accounts payable for services received from ATC	$ 24.0	$ 31.2

XML

INVESTMENT IN TRANSMISSION AFFILIATES - SUMMARIZED FINANCIAL DATA (Details) - ATC - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017	Dec. 31, 2017
Income statement data
Operating revenues	$ 165.4	$ 174.7
Operating expenses	84.9	82.7
Other expense, net	27.6	26.1
Net income	52.9	$ 65.9
Balance sheet data
Current assets	84.7		$ 87.7
Noncurrent assets	4,681.7		4,598.9
Total assets	4,766.4		4,686.6
Current liabilities	473.3		767.2
Long-term debt	2,065.3		1,790.6
Other noncurrent liabilities	266.4		240.3
Shareholders' equity	1,961.4		1,888.5
Total liabilities and shareholders' equity	$ 4,766.4		$ 4,686.6

XML

SEGMENT INFORMATION (Details) $ in Millions	3 Months Ended		12 Months Ended
	Mar. 31, 2018 USD ($) segment	Mar. 31, 2017 USD ($)	Dec. 31, 2017 USD ($)	Dec. 31, 2016 USD ($)	Dec. 31, 2015 USD ($)
Segment information
Number of reportable segments | segment	6
Revenues	$ 2,286.5	$ 2,304.5
Other operation and maintenance	511.9	504.5	$ 2,056.1	$ 2,171.3	$ 1,710.7
Depreciation and amortization	208.6	194.6
Operating income (loss)	545.1	614.7
Equity in earnings of transmission affiliates	32.8	41.9
Interest expense	106.7	104.7
Intersegment revenues
Segment information
Revenues	0.0	0.0
External Revenues
Segment information
Revenues	2,286.5	2,304.5
Electric Transmission
Segment information
Revenues	0.0
Other operation and maintenance	0.0	0.0
Depreciation and amortization	0.0	0.0
Operating income (loss)	0.0	0.0
Equity in earnings of transmission affiliates	32.8	41.9
Interest expense	0.0	0.0
Electric Transmission | Intersegment revenues
Segment information
Revenues	0.0	0.0
Electric Transmission | External Revenues
Segment information
Revenues	0.0	0.0
Non-Utility Energy Infrastructure
Segment information
Revenues	118.1
Other operation and maintenance	1.7	0.4
Depreciation and amortization	18.3	17.5
Operating income (loss)	93.0	97.4
Equity in earnings of transmission affiliates	0.0	0.0
Interest expense	16.1	15.3
Non-Utility Energy Infrastructure | Intersegment revenues
Segment information
Revenues	99.3	109.0
Non-Utility Energy Infrastructure | External Revenues
Segment information
Revenues	18.8	6.3
Corporate and Other
Segment information
Revenues	1.4
Other operation and maintenance	(0.3)	(0.4)
Depreciation and amortization	7.7	5.6
Operating income (loss)	(5.4)	(2.4)
Equity in earnings of transmission affiliates	0.0	0.0
Interest expense	28.0	29.1
Corporate and Other | Intersegment revenues
Segment information
Revenues	0.0	0.0
Corporate and Other | External Revenues
Segment information
Revenues	1.4	2.9
Reconciling Eliminations
Segment information
Other operation and maintenance	(96.8)	(109.0)
Depreciation and amortization	0.0	0.0
Operating income (loss)	0.0	0.0
Equity in earnings of transmission affiliates	0.0	0.0
Interest expense	(1.2)	(1.8)
Reconciling Eliminations | Intersegment revenues
Segment information
Revenues	(99.3)	(109.0)
Reconciling Eliminations | External Revenues
Segment information
Revenues	0.0	0.0
Public Utility
Segment information
Revenues	2,266.3
Other operation and maintenance	607.3	613.5
Depreciation and amortization	182.6	171.5
Operating income (loss)	457.5	519.7
Equity in earnings of transmission affiliates	0.0	0.0
Interest expense	63.8	62.1
Public Utility | Intersegment revenues
Segment information
Revenues	0.0	0.0
Public Utility | External Revenues
Segment information
Revenues	2,266.3	2,295.3
Public Utility | Wisconsin
Segment information
Revenues	1,589.1
Other operation and maintenance	468.5	465.7
Depreciation and amortization	135.1	129.3
Operating income (loss)	273.7	329.5
Equity in earnings of transmission affiliates	0.0	0.0
Interest expense	49.4	48.7
Public Utility | Wisconsin | Intersegment revenues
Segment information
Revenues	0.0	0.0
Public Utility | Wisconsin | External Revenues
Segment information
Revenues	1,589.1	1,612.1
Public Utility | Illinois
Segment information
Revenues	507.3
Other operation and maintenance	112.2	119.6
Depreciation and amortization	40.9	36.2
Operating income (loss)	147.6	156.7
Equity in earnings of transmission affiliates	0.0	0.0
Interest expense	12.3	11.1
Public Utility | Illinois | Intersegment revenues
Segment information
Revenues	0.0	0.0
Public Utility | Illinois | External Revenues
Segment information
Revenues	507.3	525.3
Public Utility | Other States
Segment information
Revenues	169.9
Other operation and maintenance	26.6	28.2
Depreciation and amortization	6.6	6.0
Operating income (loss)	36.2	33.5
Equity in earnings of transmission affiliates	0.0	0.0
Interest expense	2.1	2.3
Public Utility | Other States | Intersegment revenues
Segment information
Revenues	0.0	0.0
Public Utility | Other States | External Revenues
Segment information
Revenues	$ 169.9	157.9
ATC | Electric Transmission
Segment information
Equity method investment, ownership interest (as a percent)	60.00%
ATC Holdco
Segment information
Equity method investment, ownership interest (as a percent)	75.00%
Equity in earnings of transmission affiliates	$ (0.6)	$ (5.8)
ATC Holdco | Electric Transmission
Segment information
Equity method investment, ownership interest (as a percent)	75.00%

XML

VARIABLE INTEREST ENTITIES (Details) $ in Millions	3 Months Ended
	Mar. 31, 2018 USD ($) MW	Mar. 31, 2017 USD ($)	Dec. 31, 2017 USD ($)	Dec. 31, 2016 USD ($)
Variable interest entities
Equity investment	$ 1,598.9	$ 1,513.3	$ 1,553.4	$ 1,443.9
ATC
Variable interest entities
Ownership interest (as a percent)	60.00%
Equity investment	$ 1,561.1		1,515.8
ATC distributions receivable			39.9
Accounts payable due to ATC	$ 24.0		31.2
ATC Holdco
Variable interest entities
Ownership interest (as a percent)	75.00%
Equity investment	$ 37.8		$ 37.6
Purchased power agreement
Variable interest entities
Firm capacity from purchased power agreement (in megawatts) | MW	236
Minimum energy requirements over remaining term of purchased power agreement (in megawatts) | MW	0
Remaining term of purchased power agreement (in years)	4 years
Residual guarantee associated with purchased power agreement	$ 0.0
Required payments over remaining term of purchased power agreement	67.7
Total capacity and lease payments	$ 4.7	$ 4.5

XML

COMMITMENTS AND CONTINGENCIES - UNCONDITIONAL PURCHASE OBLIGATIONS (Details) $ in Millions	Mar. 31, 2018 USD ($)
Minimum future commitments for purchase obligations
Purchase obligations	$ 11,473.4

XML

COMMITMENTS AND CONTINGENCIES - ENVIRONMENTAL MATTERS (Details) T in Millions, $ in Millions	1 Months Ended	3 Months Ended	12 Months Ended
	Oct. 31, 2014 compliance_option	Mar. 31, 2018 USD ($) degreecelsius MW	Dec. 31, 2017 USD ($) T	Dec. 31, 2015	Sep. 30, 2016 Case
Climate Change | Electric
Air quality
Number of legal cases heard by a court | Case					1
Percentage of nationwide greenhouse gas emissions reduction				32.00%
Interim goal for greenhouse gas emissions reduction (fraction)				0.667
Company goal for percentage of carbon dioxide emissions reduction		40.00%
Coal Generation Capacity Expected To Be Retired By 2020 | MW		1,800
Carbon Dioxide Emissions | T			29.2
Climate Change | Electric | Maximum
Air quality
Global temperature increases limit | degreecelsius		2
Climate Change | Electric | Wisconsin
Air quality
Percentage of greenhouse gas emissions reduction by state				41.00%
Climate Change | Electric | Michigan
Air quality
Percentage of greenhouse gas emissions reduction by state				39.00%
Climate Change | Natural gas
Air quality
Carbon Dioxide Emissions | T			26.6
Clean Water Act Cooling Water Intake Structure Rule | Electric
Water quality
Number of compliance options available to meet standard | compliance_option	7
Renewal period for facility permits		5 years
Steam Electric Effluent Limitation Guidelines | Electric
Water quality
Renewal period for facility permits		5 years
Steam Electric Effluent Limitation Guidelines | Electric | Minimum
Water quality
Expected cost to achieve required emissions reductions		$ 70.0
Manufactured Gas Plant Remediation | Natural gas
Manufactured gas plant remediation
Regulatory assets recorded for remediation of manufactured gas plant sites		668.2	$ 676.6
Reserves recorded for remediation of manufactured gas plant sites		$ 617.2	$ 617.2

XML

SUPPLEMENTAL CASH FLOW INFORMATION - SUPPLEMENTAL INFORMATION (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Supplemental cash flow information
Cash (paid) for interest, net of amount capitalized	$ (68.5)	$ (56.6)
Cash received for income taxes, net	0.3	8.9
Significant non-cash transactions
Accounts payable related to construction costs	74.9	116.4
Portion of Bostco real estate holdings sale financed with note receivable	0.0	7.0
Amortization of deferred revenue	$ 6.3	$ 6.2

XML

SUPPLEMENTAL CASH FLOW INFORMATION - RECONCILIATION OF CASH AND CASH EQUIVALENTS AND RESTRICTED CASH (Details) - USD ($) $ in Millions	Mar. 31, 2018	Dec. 31, 2017	Mar. 31, 2017	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Additional Cash Flow Elements and Supplemental Cash Flow Information [Abstract]
Cash and cash equivalents	$ 48.1	$ 38.9	$ 45.7
Restricted cash included in other current assets	0.0		0.8
Restricted cash included in other long term assets	23.6		26.9
Cash, cash equivalents, and restricted cash	$ 71.7	$ 58.6	$ 73.4	$ 72.7	$ 168.8	$ 61.9

XML

SUPPLEMENTAL CASH FLOW INFORMATION - ADOPTION OF ACCOUNTING STANDARDS (Details) $ in Millions	3 Months Ended		12 Months Ended
	Mar. 31, 2018 USD ($) Provisions	Mar. 31, 2017 USD ($)	Dec. 31, 2017 USD ($)	Dec. 31, 2016 USD ($)	Dec. 31, 2015 USD ($)
Operating activities
Other current assets	$ 81.3	$ 41.2	$ (7.1)	$ 103.2	$ (27.2)
Other, net	134.3	(19.2)	(197.4)	(53.6)	(207.6)
Net cash provided by operating activities	894.0	714.6	2,078.6	2,103.8	1,295.1
Investing activities
Withdrawal of restricted cash from rabbi trust for qualifying payments			0.0	0.0	0.0
Proceeds from the sale of investments held in rabbi trust	16.5	8.6	8.7	1.7	126.9
Purchase of investments held in rabbi trust			(3.7)	(59.2)	(60.2)
Integrys acquisition, net of cash acquired			0.0	0.0	(1,299.1)
Other, net	(0.7)	2.5	12.0	3.0	55.8
Net cash used in investing activities	(435.8)	(333.1)	(2,254.1)	(1,354.2)	(2,422.6)
Financing activities
Other, net	(0.3)	(0.6)	(6.5)	(13.6)	3.7
Net cash provided by (used in) financing activities	(445.1)	(380.8)	161.4	(845.7)	1,234.4
Net change in cash, cash equivalents, and restricted cash	13.1	0.7	(14.1)	(96.1)	106.9
Cash, cash equivalents, and restricted cash at beginning of period	58.6	72.7	72.7	168.8	61.9
Cash, cash equivalents, and restricted cash at end of period	71.7	73.4	58.6	72.7	168.8
2017 Form 10-K Cash Flows
Operating activities
Other current assets			(6.0)	103.1	(27.2)
Other, net			(197.5)	(53.8)	(209.1)
Net cash provided by operating activities			2,079.6	2,103.5	1,293.6
Investing activities
Withdrawal of restricted cash from rabbi trust for qualifying payments			19.5	26.6	1.4
Proceeds from the sale of investments held in rabbi trust			0.0	0.0	0.0
Purchase of investments held in rabbi trust			0.0	0.0	0.0
Integrys acquisition, net of cash acquired			0.0	0.0	(1,329.9)
Other, net			12.0	3.0	57.0
Net cash used in investing activities			(2,239.6)	(1,270.1)	(2,517.5)
Financing activities
Other, net			(6.5)	(13.6)	(18.9)
Net cash provided by (used in) financing activities			161.4	(845.7)	1,211.8
Net change in cash, cash equivalents, and restricted cash			1.4	(12.3)	(12.1)
Cash, cash equivalents, and restricted cash at beginning of period	38.9	37.5	37.5	49.8	61.9
Cash, cash equivalents, and restricted cash at end of period			38.9	37.5	49.8
Accounting Standards Update 2016-18 | Impact of ASU 2016-18
Operating activities
Other current assets			(1.1)	0.1	0.0
Other, net			0.1	0.2	1.5
Net cash provided by operating activities			(1.0)	0.3	1.5
Investing activities
Withdrawal of restricted cash from rabbi trust for qualifying payments			(19.5)	(26.6)	(1.4)
Proceeds from the sale of investments held in rabbi trust			8.7	1.7	126.9
Purchase of investments held in rabbi trust			(3.7)	(59.2)	(60.2)
Integrys acquisition, net of cash acquired			0.0	0.0	30.8
Other, net			0.0	0.0	(1.2)
Net cash used in investing activities		(7.5)	(14.5)	(84.1)	94.9
Financing activities
Other, net			0.0	0.0	22.6
Net cash provided by (used in) financing activities			0.0	0.0	22.6
Net change in cash, cash equivalents, and restricted cash			(15.5)	(83.8)	119.0
Cash, cash equivalents, and restricted cash at beginning of period	$ 19.7	35.2	35.2	119.0	0.0
Cash, cash equivalents, and restricted cash at end of period			$ 19.7	$ 35.2	$ 119.0
Accounting Standards Update 2016-15
Adoption of ASU 2016-15
Number of provisions in ASU 2016-15 | Provisions	8
Impact on financial statements from adoption	$ 0.0	$ 0.0

XML

REGULATORY ENVIRONMENT (Details) $ in Millions	1 Months Ended									3 Months Ended
	Apr. 30, 2018 utility	Mar. 31, 2018 USD ($) customer Assurance	Feb. 28, 2018 USD ($) day Filings	Dec. 31, 2017 USD ($)	Nov. 30, 2017 USD ($)	Oct. 31, 2017 USD ($) MW	Sep. 30, 2017 USD ($) utility	Jan. 31, 2017	Aug. 31, 2016 MW	Mar. 31, 2018 customer change Assurance	Mar. 31, 2017	Apr. 02, 2018 wind_turbines MW
Regulatory environment
Corporate federal tax rate										21.00%	35.00%
Forward Wind Energy Center | Subsequent event
Regulatory environment
Number of wind turbines at Forward Wind Energy Center | wind_turbines												86
Capacity of Foward Wind Energy Center | MW												129
WE | Public Service Commission of Wisconsin (PSCW) | 2018 and 2019 rates
Regulatory environment
Approved return on equity (as a percent)							10.20%
Income Statement impact of flow through of repair related deferred tax liabilities | change										0
WE | Michigan Public Service Commission (MPSC)
Regulatory environment
Number of retail electric customers served in Michigan | customer		1								1
WG | Public Service Commission of Wisconsin (PSCW) | 2018 and 2019 rates
Regulatory environment
Approved return on equity (as a percent)							10.30%
WPS | Forward Wind Energy Center | Subsequent event
Regulatory environment
Number of utilities along with WPS that entered in an agreement to purchase Forward Wind Energy Center | utility	2
WPS | Public Service Commission of Wisconsin (PSCW) | Forward Wind Energy Center | Subsequent event
Regulatory environment
Number of utilities along with WPS that entered in an agreement to purchase Forward Wind Energy Center | utility	2
Number of wind turbines at Forward Wind Energy Center | wind_turbines												86
Capacity of Foward Wind Energy Center | MW												129
WPS | Public Service Commission of Wisconsin (PSCW) | 2018 and 2019 rates
Regulatory environment
Approved return on equity (as a percent)							10.00%
Authorized revenue requirement for the ReACT project							$ 275.0
AFUDC							51.0
Estimated cost of the ReACT project, excluding AFUDC							$ 342.0
WE, WG, and WPS | Public Service Commission of Wisconsin (PSCW) | Natural gas storage facilities in Michigan
Regulatory environment
Percentage of natural gas storage needs provided by the facilities								33.33%
WE, WG, and WPS | Public Service Commission of Wisconsin (PSCW) | 2018 and 2019 rates
Regulatory environment
Number of utilities with earnings sharing mechanism | utility							3
Percentage of first 50 basis points of additional utility earnings shared with customers							50.00%
Return on equity in excess of authorized amount (as a percent)							0.50%
WE, WG, and WPS | Public Service Commission of Wisconsin (PSCW) | 2018 and 2019 rates | Natural gas rates | Subsequent event
Regulatory environment
Percent of current tax benefit from Tax Cuts and Jobs Act of 2017 to be returned to customers via bill credits	100.00%
WE and WPS | Public Service Commission of Wisconsin (PSCW) | 2018 and 2019 rates | Electric rates | Subsequent event
Regulatory environment
Percentage of current tax benefit from Tax Cuts and Jobs Act of 2017 to be used to reduce certain regulatory assets	80.00%
Percent of current tax benefit from Tax Cuts and Jobs Act of 2017 to be returned to customers via bill credits	20.00%
PGL | Illinois Commerce Commission (ICC)
Regulatory environment
Amount of rate base reduction as a result of a settlement			$ 5.4
Amount to be refunded to ratepayers as a result of a settlement			$ 4.7
Amount of assurance that PGL's QIP rider costs will be recoverable | Assurance		0								0
MGU and UMERC | Michigan Public Service Commission (MPSC)
Regulatory environment
Number of filings required related to the Tax Cuts and Jobs Act of 2017 | Filings			3
Number of days between the first and second filing related to the impact on base rates for the change in tax expense associated with the Tax Cuts and Jobs Act of 2017 | day			30
MERC | Minnesota Public Utilities Commission (MPUC) | 2018 rates | Natural gas rates
Regulatory environment
Requested rate increase						$ 12.6
Requested rate increase (as a percent)						5.05%
Requested return on equity (as a percent)						10.30%
Requested common equity component average (as a percent)						50.90%
Interim rate increase		$ 7.0			$ 9.5
Interim rate increase, (as a percent)		2.81%			3.78%
Interim rate reduction		$ 2.5
Interim rates return on equity (as a percent)		9.10%
Interim rates common equity component average (as a percent)		50.90%
UMERC
Regulatory environment
Capacity of natural gas-fired generation facility (in megawatts) | MW						180
UMERC | Michigan Public Service Commission (MPSC)
Regulatory environment
Term of electric power purchase agreement (in years)									20 years
Capacity of natural gas-fired generation facility (in megawatts) | MW									180
Estimated cost of constructing a power plant						$ 266.0
Estimated cost of constructing a power plant, including AFUDC						$ 277.0
Portion of the power plant costs recoverable from Tilden Mining Company (as a percent)						50.00%
Portion of the power plant costs recoverable from utility customers (as a percent)						50.00%
Utility Operations | Tax Cuts And Jobs Act Of 2017
Regulatory environment
Change in deferred taxes from tax legislation				$ 2,450.0