10-Q

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

WASHINGTON, D.C. 20549

FORM 10-Q

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

For the quarterly period ended June 30, 2020

or

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

For the transition period from                    to                    

Name of Registrant, State of Incorporation, Address of Principal Executive Offices, Telephone Number, Commission File Number, IRS Employer Identification Number

ALLIANT ENERGY CORPORATION

(a Wisconsin Corporation)

4902 N. Biltmore Lane

Madison, Wisconsin 53718

Telephone (608) 458-3311

Commission File Number - 1-9894

IRS Employer Identification Number - 39-1380265

INTERSTATE POWER & LIGHT COMPANY

(an Iowa corporation)

Alliant Energy Tower

Cedar Rapids, Iowa 52401

Telephone (319) 786-4411

Commission File Number - 1-4117

IRS Employer Identification Number - 42-0331370

WISCONSIN POWER & LIGHT COMPANY

(a Wisconsin corporation)

4902 N. Biltmore Lane

Madison, Wisconsin 53718

Telephone (608) 458-3311

Commission File Number - 0-337

IRS Employer Identification Number - 39-0714890

This combined Form 10-Q is separately filed by Alliant Energy Corporation, Interstate Power and Light Company and Wisconsin Power and Light Company. Information contained in the Form 10-Q relating to Interstate Power and Light Company and Wisconsin Power and Light Company is filed by each such registrant on its own behalf. Each of Interstate Power and Light Company and Wisconsin Power and Light Company makes no representation as to information relating to registrants other than itself.

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

Alliant Energy Corporation, Common Stock, $0.01 Par Value, Trading Symbol LNT, Nasdaq Global Select Market

Interstate Power and Light Company, 5.100% Series D Cumulative Perpetual Preferred Stock, $0.01 Par Value, Trading Symbol IPLDP, Nasdaq Global Select Market

Indicate by check mark whether the registrants (1) have 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 registrants were required to file such reports), and (2) have been subject to such filing requirements for the past 90 days.

Alliant Energy Corporation - Yes ☒ No ☐

Interstate Power and Light Company - Yes ☒ No ☐

Wisconsin Power and Light Company - Yes ☒ No ☐

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

Alliant Energy Corporation - Yes ☒ No ☐

Interstate Power and Light Company - Yes ☒ No ☐

Wisconsin Power and Light Company - Yes ☒ No ☐

Indicate by check mark whether the registrants are large accelerated filers, accelerated filers, non-accelerated filers, smaller reporting companies, or emerging growth companies. See the definitions of “large accelerated filer,” “accelerated filer,” “smaller reporting company,” and “emerging growth company” in Rule 12b-2 of the Exchange Act.

Alliant Energy Corporation - Large Accelerated Filer ☒ Accelerated Filer ☐ Non-accelerated Filer ☐ Smaller Reporting Company ☐ Emerging Growth Company ☐

Interstate Power and Light Company - Large Accelerated Filer ☐ Accelerated Filer ☐ Non-accelerated Filer ☒ Smaller Reporting Company ☐ Emerging Growth Company ☐

Wisconsin Power and Light Company - Large Accelerated Filer ☐ Accelerated Filer ☐ Non-accelerated Filer ☒ Smaller Reporting Company ☐ Emerging Growth Company ☐

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

Alliant Energy Corporation ☐

Interstate Power and Light Company ☐

Wisconsin Power and Light Company ☐

Indicate by check mark whether the registrants are shell companies (as defined in Rule 12b-2 of the Exchange Act).

Alliant Energy Corporation - Yes ☐ No ☒

Interstate Power and Light Company - Yes ☐ No ☒

Wisconsin Power and Light Company - Yes ☐ No ☒

Number of shares outstanding of each class of common stock as of June 30, 2020:

Alliant Energy Corporation, Common Stock, $0.01 par value, 249,644,352 shares outstanding

Interstate Power and Light Company, Common Stock, $2.50 par value, 13,370,788 shares outstanding (all outstanding shares are owned beneficially and of record by Alliant Energy Corporation)

Wisconsin Power and Light Company, Common Stock, $5 par value, 13,236,601 shares outstanding (all outstanding shares are owned beneficially and of record by Alliant Energy Corporation)

TABLE OF CONTENTS

	Page
Definitions	1
Forward-looking Statements	1
Part I. Financial Information	3
Item 1. Condensed Consolidated Financial Statements (Unaudited)	3
Alliant Energy Corporation	3
Interstate Power and Light Company	6
Wisconsin Power and Light Company	9
Combined Notes to Condensed Consolidated Financial Statements	12
1. Summary of Significant Accounting Policies	12
2. Regulatory Matters	13
3. Receivables	13
4. Investments	14
5. Common Equity	14
6. Debt	17
7. Revenues	18
8. Income Taxes	18
9. Benefit Plans	19
10. Asset Retirement Obligations	20
11. Derivative Instruments	20
12. Fair Value Measurements	21
13. Commitments and Contingencies	23
14. Segments of Business	25
15. Related Parties	26
Item 2. Management’s Discussion and Analysis of Financial Condition and Results of Operations	27
Item 3. Quantitative and Qualitative Disclosures About Market Risk	35
Item 4. Controls and Procedures	35
Part II. Other Information	36
Item 1A. Risk Factors	36
Item 2. Unregistered Sales of Equity Securities and Use of Proceeds	36
Item 6. Exhibits	37
Signatures	37

DEFINITIONS

The following abbreviations or acronyms used in this report are defined below:

Abbreviation or Acronym	Definition	Abbreviation or Acronym	Definition
2019 Form 10-K	Combined Annual Report on Form 10-K filed by Alliant Energy, IPL and WPL for the year ended Dec. 31, 2019	GAAP	U.S. generally accepted accounting principles
AEF	Alliant Energy Finance, LLC	IPL	Interstate Power and Light Company
Alliant Energy	Alliant Energy Corporation	IUB	Iowa Utilities Board
ATC	American Transmission Company LLC	MDA	Management’s Discussion and Analysis of Financial Condition and Results of Operations
ATC Holdings	Interest in American Transmission Company LLC and ATC Holdco LLC	MISO	Midcontinent Independent System Operator, Inc.
Corporate Services	Alliant Energy Corporate Services, Inc.	MW	Megawatt
COVID-19	Novel coronavirus	MWh	Megawatt-hour
DAEC	Duane Arnold Energy Center	N/A	Not applicable
Dth	Dekatherm	Note(s)	Combined Notes to Condensed Consolidated Financial Statements
EGU	Electric generating unit	OPEB	Other postretirement benefits
EPA	U.S. Environmental Protection Agency	PPA	Purchased power agreement
EPS	Earnings per weighted average common share	PSCW	Public Service Commission of Wisconsin
Federal Tax Reform	Tax Cuts and Jobs Act	U.S.	United States of America
FERC	Federal Energy Regulatory Commission	Whiting Petroleum	Whiting Petroleum Corporation
Financial Statements	Condensed Consolidated Financial Statements	WPL	Wisconsin Power and Light Company
FTR	Financial transmission right

FORWARD-LOOKING STATEMENTS

Statements contained in this report that are not of historical fact are forward-looking statements intended to qualify for the safe harbors from liability established by the Private Securities Litigation Reform Act of 1995. These forward-looking statements can be identified as such because the statements include words such as “may,” “believe,” “expect,” “anticipate,” “plan,” “project,” “will,” “projections,” “estimate,” or other words of similar import. Similarly, statements that describe future financial performance or plans or strategies are forward-looking statements. Such forward-looking statements are subject to certain risks and uncertainties that could cause actual results to differ materially from those expressed in, or implied by, such statements. Some, but not all, of the risks and uncertainties of Alliant Energy, IPL and WPL that could materially affect actual results include:

• IPL’s and WPL’s ability to obtain adequate and timely rate relief to allow for, among other things, the recovery of and/or the return on costs, including fuel costs, operating costs, transmission costs, deferred expenditures, deferred tax assets, tax expense, capital expenditures, and remaining costs related to EGUs that may be permanently closed and certain other retired assets, decreases in sales volumes, earning their authorized rates of return, and the payments to their parent of expected levels of dividends;

• federal and state regulatory or governmental actions, including the impact of legislation, and regulatory agency orders;

• the direct or indirect effects resulting from the COVID-19 pandemic on sales volumes, margins, operations, employees, contractors, vendors, the ability to complete construction projects, supply chains, customers’ inability to pay bills, suspension of disconnects and waiving of late fees applied to past due accounts, the market value of the assets that fund pension plans and the potential for additional funding requirements, the ability of counterparties to meet their obligations, compliance with regulatory requirements, the ability to implement regulatory plans, economic conditions and access to capital markets;

• the impact of customer- and third party-owned generation, including alternative electric suppliers, in IPL’s and WPL’s service territories on system reliability, operating expenses and customers’ demand for electricity;

• the impact of energy efficiency, franchise retention and customer disconnects on sales volumes and margins;

• the impact that price changes may have on IPL’s and WPL’s customers’ demand for electric, gas and steam services and their ability to pay their bills;

• the ability to utilize tax credits and net operating losses generated to date, and those that may be generated in the future, before they expire;

• the direct or indirect effects resulting from terrorist incidents, including physical attacks and cyber attacks, or responses to such incidents;

• the impact of penalties or third-party claims related to, or in connection with, a failure to maintain the security of personally identifiable information, including associated costs to notify affected persons and to mitigate their information security concerns;

• any material post-closing payments related to any past asset divestitures, including the sale of Whiting Petroleum, which could result from, among other things, indemnification agreements, warranties, guarantees or litigation;

1

• employee workforce factors, including changes in key executives, ability to hire and retain employees with specialized skills, ability to create desired corporate culture, collective bargaining agreements and negotiations, work stoppages or restructurings;

• weather effects on results of utility operations;

• issues associated with environmental remediation and environmental compliance, including compliance with all environmental and emissions permits, the Coal Combustion Residuals Rule, future changes in environmental laws and regulations, including federal, state or local regulations for carbon dioxide emissions reductions from new and existing fossil-fueled EGUs, and litigation associated with environmental requirements;

• increased pressure from customers, investors and other stakeholders to more rapidly reduce carbon dioxide emissions;

• the ability to defend against environmental claims brought by state and federal agencies, such as the EPA, state natural resources agencies or third parties, such as the Sierra Club, and the impact on operating expenses of defending and resolving such claims;

• continued access to the capital markets on competitive terms and rates, and the actions of credit rating agencies;

• inflation and interest rates;

• the ability to complete construction of wind and solar projects within the cost caps set by regulators and to meet all requirements to qualify for the full level of production tax credits and investment tax credits, respectively;

• changes in the price of delivered natural gas, purchased electricity and coal due to shifts in supply and demand caused by market conditions and regulations;

• disruptions in the supply and delivery of natural gas, purchased electricity and coal;

• the direct or indirect effects resulting from breakdown or failure of equipment in the operation of electric and gas distribution systems, such as mechanical problems and explosions or fires, and compliance with electric and gas transmission and distribution safety regulations, including regulations promulgated by the Pipeline and Hazardous Materials Safety Administration;

• issues related to the availability and operations of EGUs, including start-up risks, breakdown or failure of equipment, performance below expected or contracted levels of output or efficiency, operator error, employee safety, transmission constraints, compliance with mandatory reliability standards and risks related to recovery of resulting incremental costs through rates;

• impacts that excessive heat, storms or natural disasters may have on Alliant Energy’s, IPL’s and WPL’s operations and recovery of costs associated with restoration activities, or on the operations of Alliant Energy’s investments;

• Alliant Energy’s ability to sustain its dividend payout ratio goal;

• changes to costs of providing benefits and related funding requirements of pension and OPEB plans due to the market value of the assets that fund the plans, economic conditions, financial market performance, interest rates, life expectancies and demographics;

• material changes in employee-related benefit and compensation costs;

• risks associated with operation and ownership of non-utility holdings;

• changes in technology that alter the channels through which customers buy or utilize Alliant Energy’s, IPL’s or WPL’s products and services;

• impacts on equity income from unconsolidated investments from valuations and potential changes to ATC’s authorized return on equity;

• impacts of IPL’s future tax benefits from Iowa rate-making practices, including deductions for repairs expenditures, allocation of mixed service costs and state depreciation, and recoverability of the associated regulatory assets from customers, when the differences reverse in future periods;

• the impacts of changes in tax rates, including adjustments made to deferred tax assets and liabilities;

• changes to the creditworthiness of counterparties with which Alliant Energy, IPL and WPL have contractual arrangements, including participants in the energy markets and fuel suppliers and transporters;

• current or future litigation, regulatory investigations, proceedings or inquiries;

• reputational damage from negative publicity, protests, fines, penalties and other negative consequences resulting in regulatory and/or legal actions;

• the effect of accounting standards issued periodically by standard-setting bodies;

• the ability to successfully complete tax audits and changes in tax accounting methods with no material impact on earnings and cash flows; and

• other factors listed in MDA and Item 1A Risk Factors, as well as Risk Factors in Item 1A in the 2019 Form 10-K.

Alliant Energy, IPL and WPL each assume no obligation, and disclaim any duty, to update the forward-looking statements in this report, except as required by law.

2

PART I. FINANCIAL INFORMATION

ITEM 1. CONDENSED CONSOLIDATED FINANCIAL STATEMENTS (UNAUDITED)

ALLIANT ENERGY CORPORATION

CONDENSED CONSOLIDATED STATEMENTS OF INCOME (UNAUDITED)

	For the Three Months						For the Six Months
	Ended June 30,						Ended June 30,
	2020			2019			2020			2019
	(in millions, except per share amounts)
Revenues:
Electric utility		$675.2			$691.2			$1,405.5			$1,434.6
Gas utility	58.9			65.2			211.1			281.0
Other utility	10.1			10.9			21.7			22.0
Non-utility	18.9			22.9			40.5			39.8
Total revenues	763.1			790.2			1,678.8			1,777.4
Operating expenses:
Electric production fuel and purchased power	163.5			164.8			347.6			383.2
Electric transmission service	71.6			112.4			193.8			235.4
Cost of gas sold	20.9			20.4			105.9			142.0
Other operation and maintenance	159.8			172.3			322.0			353.5
Depreciation and amortization	152.1			142.9			298.4			279.8
Taxes other than income taxes	27.1			27.6			54.7			56.9
Total operating expenses	595.0			640.4			1,322.4			1,450.8
Operating income	168.1			149.8			356.4			326.6
Other (income) and deductions:
Interest expense	69.6			69.2			138.5			135.5
Equity income from unconsolidated investments, net	(17.4		)	(12.7		)	(30.8		)	(23.6		)
Allowance for funds used during construction	(15.2		)	(18.3		)	(38.2		)	(43.7		)
Other	2.5			3.3			4.4			7.3
Total other (income) and deductions	39.5			41.5			73.9			75.5
Income before income taxes	128.6			108.3			282.5			251.1
Income tax expense (benefit)	(8.3		)	11.2			(27.0		)	26.3
Net income	136.9			97.1			309.5			224.8
Preferred dividend requirements of Interstate Power and Light Company	2.5			2.5			5.1			5.1
Net income attributable to Alliant Energy common shareowners		$134.4			$94.6			$304.4			$219.7
Weighted average number of common shares outstanding:
Basic	249.6			237.5			247.0			237.0
Diluted	249.8			238.1			247.2			237.3
Earnings per weighted average common share attributable to Alliant Energy common shareowners (basic and diluted)		$0.54			$0.40			$1.23			$0.93

Refer to accompanying Combined Notes to Condensed Consolidated Financial Statements.

3

ALLIANT ENERGY CORPORATION

CONDENSED CONSOLIDATED BALANCE SHEETS (UNAUDITED)

	June 30, 2020		December 31, 2019
	(in millions, except per share and share amounts)
ASSETS
Current assets:
Cash and cash equivalents		$208.1		$16.3
Accounts receivable, less allowance for expected credit losses	386.5		402.1
Production fuel, at weighted average cost	78.0		77.7
Gas stored underground, at weighted average cost	36.8		49.1
Materials and supplies, at weighted average cost	107.0		100.5
Regulatory assets	94.5		86.4
Other	133.4		143.4
Total current assets	1,044.3		875.5
Property, plant and equipment, net	13,936.4		13,527.1
Investments:
ATC Holdings	326.1		320.1
Other	147.1		147.7
Total investments	473.2		467.8
Other assets:
Regulatory assets	1,748.5		1,758.3
Deferred charges and other	67.3		72.0
Total other assets	1,815.8		1,830.3
Total assets		$17,269.7		$16,700.7

LIABILITIES AND EQUITY
Current liabilities:
Current maturities of long-term debt		$7.4			$657.2
Commercial paper	185.4			337.4
Accounts payable	429.9			422.3
Regulatory liabilities	211.4			212.0
Other	386.8			425.2
Total current liabilities	1,220.9			2,054.1
Long-term debt, net (excluding current portion)	6,572.4			5,533.0
Other liabilities:
Deferred tax liabilities	1,761.3			1,714.0
Regulatory liabilities	1,159.6			1,211.6
Pension and other benefit obligations	450.2			484.0
Other	357.0			298.9
Total other liabilities	3,728.1			3,708.5
Commitments and contingencies (Note 13)
Equity:
Alliant Energy Corporation common equity:
Common stock - $0.01 par value - 480,000,000 shares authorized; 249,644,352 and 245,022,800 shares	2.5			2.5
Additional paid-in capital	2,683.1			2,445.9
Retained earnings	2,873.5			2,765.4
Accumulated other comprehensive income (loss)	(0.6		)	1.3
Shares in deferred compensation trust - 367,493 and 381,232 shares at a weighted average cost of $27.86 and $26.24 per share	(10.2		)	(10.0		)
Total Alliant Energy Corporation common equity	5,548.3			5,205.1
Cumulative preferred stock of Interstate Power and Light Company	200.0			200.0
Total equity	5,748.3			5,405.1
Total liabilities and equity		$17,269.7			$16,700.7

Refer to accompanying Combined Notes to Condensed Consolidated Financial Statements.

4

ALLIANT ENERGY CORPORATION

CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS (UNAUDITED)

	For the Six Months
	Ended June 30,
	2020			2019
	(in millions)
Cash flows from operating activities:
Net income		$309.5			$224.8
Adjustments to reconcile net income to net cash flows from operating activities:
Depreciation and amortization	298.4			279.8
Deferred tax expense (benefit) and tax credits	(28.8		)	19.9
Equity component of allowance for funds used during construction	(26.8		)	(30.8		)
Other	26.6			13.5
Other changes in assets and liabilities:
Accounts receivable	(197.9		)	(199.7		)
Accounts payable	8.3			(33.1		)
Regulatory liabilities	(63.4		)	(26.1		)
Pension and other benefit obligations	(33.8		)	(21.7		)
Deferred income taxes	81.9			34.3
Other	(54.3		)	16.0
Net cash flows from operating activities	319.7			276.9
Cash flows used for investing activities:
Construction and acquisition expenditures:
Utility business	(584.0		)	(652.5		)
Other	(24.3		)	(54.1		)
Cash receipts on sold receivables	209.9			125.5
Other	6.1			(25.9		)
Net cash flows used for investing activities	(392.3		)	(607.0		)
Cash flows from financing activities:
Common stock dividends	(187.6		)	(167.8		)
Proceeds from issuance of common stock, net	234.8			60.6
Proceeds from issuance of long-term debt	1,050.0			650.0
Payments to retire long-term debt	(653.7		)	(3.4		)
Net change in commercial paper	(152.0		)	(50.7		)
Other	(27.2		)	(9.9		)
Net cash flows from financing activities	264.3			478.8
Net increase in cash, cash equivalents and restricted cash	191.7			148.7
Cash, cash equivalents and restricted cash at beginning of period	17.7			25.5
Cash, cash equivalents and restricted cash at end of period		$209.4			$174.2
Supplemental cash flows information:
Cash (paid) refunded during the period for:
Interest		($138.1	)		($132.7	)
Income taxes, net		($5.0	)		$2.5
Significant non-cash investing and financing activities:
Accrued capital expenditures		$208.3			$187.4
Beneficial interest obtained in exchange for securitized accounts receivable		$194.1			$214.6

Refer to accompanying Combined Notes to Condensed Consolidated Financial Statements.

5

INTERSTATE POWER AND LIGHT COMPANY

CONDENSED CONSOLIDATED STATEMENTS OF INCOME (UNAUDITED)

	For the Three Months						For the Six Months
	Ended June 30,						Ended June 30,
	2020			2019			2020			2019
	(in millions)
Revenues:
Electric utility		$388.4			$392.3			$813.2			$812.1
Gas utility	33.9			38.4			116.9			163.0
Steam and other	9.6			10.5			20.7			21.2
Total revenues	431.9			441.2			950.8			996.3
Operating expenses:
Electric production fuel and purchased power	96.0			83.3			202.2			212.2
Electric transmission service	34.0			77.4			118.5			165.1
Cost of gas sold	12.4			10.8			56.6			74.1
Other operation and maintenance	97.5			97.4			184.1			205.4
Depreciation and amortization	88.7			82.6			174.6			159.7
Taxes other than income taxes	14.6			15.2			29.4			31.8
Total operating expenses	343.2			366.7			765.4			848.3
Operating income	88.7			74.5			185.4			148.0
Other (income) and deductions:
Interest expense	34.8			31.5			69.3			60.9
Allowance for funds used during construction	(5.6		)	(7.9		)	(15.4		)	(23.7		)
Other	1.0			1.5			1.9			3.4
Total other (income) and deductions	30.2			25.1			55.8			40.6
Income before income taxes	58.5			49.4			129.6			107.4
Income tax expense (benefit)	(3.8		)	1.9			(17.9		)	4.0
Net income	62.3			47.5			147.5			103.4
Preferred dividend requirements	2.5			2.5			5.1			5.1
Net income available for common stock		$59.8			$45.0			$142.4			$98.3

Earnings per share data is not disclosed given Alliant Energy Corporation is the sole shareowner of all shares of IPL’s common stock outstanding during the periods presented.

Refer to accompanying Combined Notes to Condensed Consolidated Financial Statements.

6

INTERSTATE POWER AND LIGHT COMPANY

CONDENSED CONSOLIDATED BALANCE SHEETS (UNAUDITED)

	June 30, 2020		December 31, 2019
	(in millions, except per share and share amounts)
ASSETS
Current assets:
Cash and cash equivalents		$203.5		$9.3
Accounts receivable, less allowance for expected credit losses	208.9		202.8
Production fuel, at weighted average cost	54.8		47.1
Gas stored underground, at weighted average cost	10.4		21.7
Materials and supplies, at weighted average cost	60.4		55.0
Regulatory assets	54.0		43.5
Other	32.5		30.0
Total current assets	624.5		409.4
Property, plant and equipment, net	7,666.3		7,480.7
Other assets:
Regulatory assets	1,350.9		1,355.8
Deferred charges and other	37.9		31.6
Total other assets	1,388.8		1,387.4
Total assets		$9,679.6		$9,277.5

LIABILITIES AND EQUITY
Current liabilities:
Current maturities of long-term debt		$—		$200.0
Accounts payable	207.3		207.0
Regulatory liabilities	131.1		115.9
Other	293.8		307.6
Total current liabilities	632.2		830.5
Long-term debt, net (excluding current portion)	3,343.5		2,947.3
Other liabilities:
Deferred tax liabilities	1,012.7		1,008.0
Regulatory liabilities	586.8		598.8
Pension and other benefit obligations	160.1		167.7
Other	273.2		253.4
Total other liabilities	2,032.8		2,027.9
Commitments and contingencies (Note 13)
Equity:
Interstate Power and Light Company common equity:
Common stock - $2.50 par value - 24,000,000 shares authorized; 13,370,788 shares outstanding	33.4		33.4
Additional paid-in capital	2,522.8		2,347.8
Retained earnings	914.9		890.6
Total Interstate Power and Light Company common equity	3,471.1		3,271.8
Cumulative preferred stock	200.0		200.0
Total equity	3,671.1		3,471.8
Total liabilities and equity		$9,679.6		$9,277.5

Refer to accompanying Combined Notes to Condensed Consolidated Financial Statements.

7

INTERSTATE POWER AND LIGHT COMPANY

CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS (UNAUDITED)

	For the Six Months
	Ended June 30,
	2020			2019
	(in millions)
Cash flows from operating activities:
Net income		$147.5			$103.4
Adjustments to reconcile net income to net cash flows from operating activities:
Depreciation and amortization	174.6			159.7
Deferred tax benefit and tax credits	(20.9		)	(11.7		)
Other	(5.8		)	(14.9		)
Other changes in assets and liabilities:
Accounts receivable	(218.7		)	(209.3		)
Accounts payable	26.1			(17.0		)
Deferred income taxes	25.6			25.3
Other	(51.2		)	53.5
Net cash flows from operating activities	77.2			89.0
Cash flows used for investing activities:
Construction and acquisition expenditures	(309.6		)	(449.5		)
Cash receipts on sold receivables	209.9			125.5
Other	(25.5		)	(30.5		)
Net cash flows used for investing activities	(125.2		)	(354.5		)
Cash flows from financing activities:
Common stock dividends	(118.1		)	(83.9		)
Capital contributions from parent	175.0			100.0
Proceeds from issuance of long-term debt	400.0			300.0
Payments to retire long-term debt	(200.0		)	—
Net change in commercial paper	—			(50.4		)
Other	(14.7		)	(6.2		)
Net cash flows from financing activities	242.2			259.5
Net increase (decrease) in cash, cash equivalents and restricted cash	194.2			(6.0		)
Cash, cash equivalents and restricted cash at beginning of period	9.3			12.4
Cash, cash equivalents and restricted cash at end of period		$203.5			$6.4
Supplemental cash flows information:
Cash (paid) refunded during the period for:
Interest		($71.6	)		($58.3	)
Income taxes, net		$7.3			$12.1
Significant non-cash investing and financing activities:
Accrued capital expenditures		$93.8			$117.4
Beneficial interest obtained in exchange for securitized accounts receivable		$194.1			$214.6

Refer to accompanying Combined Notes to Condensed Consolidated Financial Statements.

8

WISCONSIN POWER AND LIGHT COMPANY

CONDENSED CONSOLIDATED STATEMENTS OF INCOME (UNAUDITED)

	For the Three Months						For the Six Months
	Ended June 30,						Ended June 30,
	2020			2019			2020			2019
	(in millions)
Revenues:
Electric utility		$286.8			$298.9			$592.3			$622.5
Gas utility	25.0			26.8			94.2			118.0
Other	0.5			0.4			1.0			0.8
Total revenues	312.3			326.1			687.5			741.3
Operating expenses:
Electric production fuel and purchased power	67.5			81.5			145.4			171.0
Electric transmission service	37.6			35.0			75.3			70.3
Cost of gas sold	8.5			9.6			49.3			67.9
Other operation and maintenance	53.2			62.4			107.4			125.9
Depreciation and amortization	62.0			59.1			121.1			117.7
Taxes other than income taxes	11.8			11.5			23.5			23.4
Total operating expenses	240.6			259.1			522.0			576.2
Operating income	71.7			67.0			165.5			165.1
Other (income) and deductions:
Interest expense	27.3			26.1			52.4			51.9
Allowance for funds used during construction	(9.5		)	(10.4		)	(22.7		)	(20.0		)
Other	0.8			1.6			1.3			3.2
Total other (income) and deductions	18.6			17.3			31.0			35.1
Income before income taxes	53.1			49.7			134.5			130.0
Income tax expense (benefit)	(4.5		)	7.7			(12.7		)	22.3
Net income		$57.6			$42.0			$147.2			$107.7

Earnings per share data is not disclosed given Alliant Energy Corporation is the sole shareowner of all shares of WPL’s common stock outstanding during the periods presented.

Refer to accompanying Combined Notes to Condensed Consolidated Financial Statements.

9

WISCONSIN POWER AND LIGHT COMPANY

CONDENSED CONSOLIDATED BALANCE SHEETS (UNAUDITED)

	June 30, 2020		December 31, 2019
	(in millions, except per share and share amounts)
ASSETS
Current assets:
Cash and cash equivalents		$3.2		$4.4
Accounts receivable, less allowance for expected credit losses	166.9		190.9
Production fuel, at weighted average cost	23.1		30.6
Gas stored underground, at weighted average cost	26.4		27.4
Materials and supplies, at weighted average cost	44.3		43.1
Regulatory assets	40.5		42.9
Other	52.1		103.4
Total current assets	356.5		442.7
Property, plant and equipment, net	5,867.2		5,638.3
Other assets:
Regulatory assets	397.6		402.5
Deferred charges and other	27.1		23.0
Total other assets	424.7		425.5
Total assets		$6,648.4		$6,506.5

LIABILITIES AND EQUITY
Current liabilities:
Current maturities of long-term debt		$—		$150.0
Commercial paper	37.9		168.2
Accounts payable	183.0		159.9
Accounts payable to associated companies	28.9		41.8
Regulatory liabilities	80.3		96.1
Other	79.5		74.3
Total current liabilities	409.6		690.3
Long-term debt, net (excluding current portion)	2,129.4		1,782.7
Other liabilities:
Deferred tax liabilities	667.4		626.2
Regulatory liabilities	572.8		612.8
Finance lease obligations - Sheboygan Falls Energy Facility	46.7		51.4
Pension and other benefit obligations	201.8		210.8
Other	168.9		168.7
Total other liabilities	1,657.6		1,669.9
Commitments and contingencies (Note 13)
Equity:
Wisconsin Power and Light Company common equity:
Common stock - $5 par value - 18,000,000 shares authorized; 13,236,601 shares outstanding	66.2		66.2
Additional paid-in capital	1,459.0		1,434.0
Retained earnings	926.6		863.4
Total Wisconsin Power and Light Company common equity	2,451.8		2,363.6
Total liabilities and equity		$6,648.4		$6,506.5

Refer to accompanying Combined Notes to Condensed Consolidated Financial Statements.

10

WISCONSIN POWER AND LIGHT COMPANY

CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS (UNAUDITED)

	For the Six Months
	Ended June 30,
	2020			2019
	(in millions)
Cash flows from operating activities:
Net income		$147.2			$107.7
Adjustments to reconcile net income to net cash flows from operating activities:
Depreciation and amortization	121.1			117.7
Other	(18.9		)	17.0
Other changes in assets and liabilities:
Accounts receivable	23.1			7.6
Regulatory liabilities	(63.3		)	(18.4		)
Deferred income taxes	53.2			11.2
Other	(6.1		)	(34.6		)
Net cash flows from operating activities	256.3			208.2
Cash flows used for investing activities:
Construction and acquisition expenditures	(274.4		)	(203.0		)
Other	14.6			(15.0		)
Net cash flows used for investing activities	(259.8		)	(218.0		)
Cash flows from financing activities:
Common stock dividends	(84.0		)	(72.0		)
Capital contributions from parent	25.0			—
Proceeds from issuance of long-term debt	350.0			350.0
Payments to retire long-term debt	(150.0		)	—
Net change in commercial paper	(130.3		)	(105.5		)
Other	(8.4		)	(7.4		)
Net cash flows from financing activities	2.3			165.1
Net increase (decrease) in cash, cash equivalents and restricted cash	(1.2		)	155.3
Cash, cash equivalents and restricted cash at beginning of period	4.4			9.2
Cash, cash equivalents and restricted cash at end of period		$3.2			$164.5
Supplemental cash flows information:
Cash (paid) refunded during the period for:
Interest		($49.7	)		($51.7	)
Income taxes, net		$1.1			($6.5	)
Significant non-cash investing and financing activities:
Accrued capital expenditures		$113.7			$66.4

Refer to accompanying Combined Notes to Condensed Consolidated Financial Statements.

11

ALLIANT ENERGY CORPORATION

INTERSTATE POWER AND LIGHT COMPANY

WISCONSIN POWER AND LIGHT COMPANY

COMBINED NOTES TO CONDENSED CONSOLIDATED FINANCIAL STATEMENTS (UNAUDITED)

NOTE 1. SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES

NOTE 1(a) General - The interim unaudited Financial Statements included herein have been prepared pursuant to the rules and regulations of the Securities and Exchange Commission. Accordingly, certain information and note disclosures normally included in financial statements prepared in accordance with GAAP have been condensed or omitted, although management believes that the disclosures are adequate to make the information presented not misleading. These Financial Statements should be read in conjunction with the financial statements and the notes thereto included in the latest combined Annual Report on Form 10-K.

In the opinion of management, all adjustments, which unless otherwise noted are normal and recurring in nature, necessary for a fair presentation of the results of operations, financial position and cash flows have been made. Results for the six months ended June 30, 2020 are not necessarily indicative of results that may be expected for the year ending December 31, 2020.

In March 2020, COVID-19 was declared a global pandemic, which has resulted in widespread travel restrictions and closures of commercial spaces and industrial facilities in Alliant Energy’s service territories. For the three and six months ended June 30, 2020, Alliant Energy, IPL and WPL considered the impact of COVID-19 on their overall business operations, financial condition, results of operations and cash flows, along with assumptions and estimates used. While the total expected impact of COVID-19 on future sales is currently unknown, Alliant Energy, IPL and WPL have experienced higher electric residential sales and lower electric commercial and industrial sales since the outset of the pandemic. The degree to which the COVID-19 pandemic may impact Alliant Energy, IPL and WPL in the future is currently unknown and will depend on future developments of the pandemic as well as possible additional actions by government and regulatory authorities.

A change in management’s estimates or assumptions could have a material impact on financial condition and results of operations during the period in which such change occurred. Certain prior period amounts in the Financial Statements and Notes have been reclassified to conform to the current period presentation for comparative purposes.

NOTE 1(b) Cash and Cash Equivalents - At June 30, 2020, Alliant Energy’s and IPL’s cash and cash equivalents included $198.3 million and $198.3 million of money market fund investments, with weighted average interest rates of 0.1% and 0.1%, respectively.

NOTE 1(c) Current Expected Credit Losses Estimates - Current expected credit losses are estimated for trade and other receivables and credit exposures on guarantees of the performance by third parties. The current expected credit losses for short-term trade receivables are based on estimates of losses resulting from the inability of customers to make required payments. The methodology used to estimate losses is based on historical write-offs, regional economic conditions, significant events that could impact collectability, such as impacts related to COVID-19 and related regulatory actions, and forecasted changes to the accounts receivable aging portfolio and write-offs. The current expected credit losses related to guarantees of the performance by third parties are estimated using both quantitative and qualitative information, which utilizes potential outcomes in a range of possible estimated amounts.

NOTE 1(d) New Accounting Standards -

Credit Losses - In June 2016, the Financial Accounting Standards Board issued an accounting standard requiring use of a current expected credit loss model rather than an incurred loss method, which is intended to result in more timely recognition of credit losses on trade receivables, certain other assets and off-balance sheet credit exposures. Alliant Energy, IPL and WPL adopted this standard on January 1, 2020 using a modified retrospective method of adoption, which required cumulative effect adjustments to retained earnings on January 1, 2020. IPL and WPL did not record a cumulative effect adjustment to retained earnings and Alliant Energy recorded a pre-tax $12 million (after-tax $8.7 million) cumulative effect adjustment to decrease retained earnings related to Alliant Energy’s guarantees in the partnership obligations of an affiliate of Whiting Petroleum (refer to Note 13(c) for further discussion). This adjustment is included in “Adoption of new accounting standard” in Alliant Energy’s summary of changes in shareowners’ equity in Note 5 for the six months ended June 30, 2020.

12

NOTE 2. REGULATORY MATTERS

Regulatory Assets and Regulatory Liabilities -

Regulatory assets were comprised of the following items (in millions):

	Alliant Energy				IPL				WPL
	June 30, 2020		December 31, 2019		June 30, 2020		December 31, 2019		June 30, 2020		December 31, 2019
Tax-related		$842.5		$817.6		$797.4		$776.8		$45.1		$40.8
Pension and OPEB costs	501.2		524.0		251.3		262.5		249.9		261.5
Assets retired early	122.9		134.0		81.8		87.9		41.1		46.1
Asset retirement obligations	114.0		111.8		78.2		76.2		35.8		35.6
IPL’s DAEC PPA amendment	109.4		108.2		109.4		108.2		—		—
Derivatives	47.0		39.5		20.5		18.3		26.5		21.2
Emission allowances	19.8		21.1		19.8		21.1		—		—
Other	86.2		88.5		46.5		48.3		39.7		40.2
		$1,843.0		$1,844.7		$1,404.9		$1,399.3		$438.1		$445.4

Regulatory liabilities were comprised of the following items (in millions):

	Alliant Energy				IPL				WPL
	June 30, 2020		December 31, 2019		June 30, 2020		December 31, 2019		June 30, 2020		December 31, 2019
Tax-related		$779.0		$835.6		$343.6		$350.9		$435.4		$484.7
Cost of removal obligations	385.8		387.7		256.4		257.0		129.4		130.7
Electric transmission cost recovery	66.3		88.6		30.7		51.3		35.6		37.3
Commodity cost recovery	30.1		24.2		14.0		8.8		16.1		15.4
Derivatives	28.8		19.9		26.3		17.4		2.5		2.5
WPL’s earnings sharing mechanism	20.4		21.9		—		—		20.4		21.9
Other	60.6		45.7		46.9		29.3		13.7		16.4
		$1,371.0		$1,423.6		$717.9		$714.7		$653.1		$708.9

Tax-related - Alliant Energy’s, IPL’s and WPL’s tax-related regulatory liabilities are primarily related to excess deferred tax benefits resulting from the remeasurement of accumulated deferred income taxes caused by Federal Tax Reform. During the six months ended June 30, 2020, Alliant Energy’s, IPL’s and WPL’s tax-related regulatory liabilities decreased primarily from returning a portion of these excess deferred tax benefits back to customers.

Electric transmission cost recovery - In the second quarter of 2020, pursuant to a June 2020 IUB order, IPL issued $42 million of credits to its retail electric customers through its transmission cost rider for amounts previously collected in rates, which resulted in a corresponding reduction to “Electric transmission service” expense in Alliant Energy’s and IPL’s income statements for the three and six months ended June 30, 2020.

Refer to Note 13(f) for discussion of refunds received by IPL and WPL in the second quarter of 2020 related to MISO transmission owner return on equity complaints.

NOTE 3. RECEIVABLES

Note 3(a) Accounts Receivable - Details for accounts receivable included on the balance sheets were as follows (in millions):

	Alliant Energy						IPL						WPL
	June 30, 2020			December 31, 2019			June 30, 2020			December 31, 2019			June 30, 2020			December 31, 2019
Customer		$92.7			$91.6			$—			$—			$82.4			$83.5
Unbilled utility revenues	68.2			82.1			—			—			68.2			82.1
Deferred proceeds	194.1			187.7			194.1			187.7			—			—
Other	41.5			48.0			16.5			16.3			24.5			31.4
Allowance for expected credit losses	(10.0		)	(7.3		)	(1.7		)	(1.2		)	(8.2		)	(6.1		)
		$386.5			$402.1			$208.9			$202.8			$166.9			$190.9

13

Note 3(b) Sales of Accounts Receivable - IPL maintains a Receivables Purchase and Sale Agreement (Receivables Agreement) whereby it may sell its customer accounts receivables, unbilled revenues and certain other accounts receivables to a third party through wholly-owned and consolidated special purpose entities. The transfers of receivables meet the criteria for sale accounting established by the transfer of financial assets accounting rules. As of June 30, 2020, IPL had $89 million of available capacity under its sales of accounts receivable program. IPL’s maximum and average outstanding cash proceeds (based on daily outstanding balances) related to the sales of accounts receivable program for the three and six months ended June 30 were as follows (in millions):

	Three Months				Six Months
	2020		2019		2020		2019
Maximum outstanding aggregate cash proceeds		$65.0		$25.0		$96.0		$108.0
Average outstanding aggregate cash proceeds	11.1		2.6		17.3		41.6

The attributes of IPL’s receivables sold under the Receivables Agreement were as follows (in millions):

	June 30, 2020		December 31, 2019
Customer accounts receivable		$113.5		$124.7
Unbilled utility revenues	92.3		95.5
Other receivables	0.4		0.9
Receivables sold to third party	206.2		221.1
Less: cash proceeds	1.0		27.0
Deferred proceeds	205.2		194.1
Less: allowance for expected credit losses	11.1		6.4
Fair value of deferred proceeds		$194.1		$187.7

As of June 30, 2020, outstanding receivables past due under the Receivables Agreement were $25.1 million. Additional attributes of IPL’s receivables sold under the Receivables Agreement for the three and six months ended June 30 were as follows (in millions):

	Three Months				Six Months
	2020		2019		2020		2019
Collections		$453.0		$487.7		$994.4		$1,043.5
Write-offs, net of recoveries	1.2		2.6		3.3		8.1

NOTE 4. INVESTMENTS

Unconsolidated Equity Investments - Alliant Energy’s equity (income) loss from unconsolidated investments accounted for under the equity method of accounting for the three and six months ended June 30 was as follows (in millions):

	Three Months						Six Months
	2020			2019			2020			2019
ATC Holdings		($13.5	)		($10.0	)		($24.5	)		($19.5	)
Non-utility wind farm in Oklahoma	(1.9		)	(1.3		)	(4.1		)	(2.4		)
Other	(2.0		)	(1.4		)	(2.2		)	(1.7		)
		($17.4	)		($12.7	)		($30.8	)		($23.6	)

NOTE 5. COMMON EQUITY

Common Share Activity - A summary of Alliant Energy’s common stock activity was as follows:

Shares outstanding, January 1, 2020	245,022,800
Equity forward agreements	4,275,127
Shareowner Direct Plan	248,220
Equity-based compensation plans	98,205
Shares outstanding, June 30, 2020	249,644,352

Equity Forward Agreements - In November 2019, Alliant Energy entered into forward sale agreements with a counterparty in connection with a public offering of 4,275,127 shares of Alliant Energy common stock. The initial forward sale price of $52.235 per share was subject to daily adjustment based on a floating interest rate factor, and decreased by other fixed amounts specified in the forward sale agreements. In the first quarter of 2020, Alliant Energy settled $222 million under the forward sale agreements by delivering 4,275,127 shares of newly issued Alliant Energy common stock at a weighted average forward sale price of $51.98 per share. Alliant Energy used the net proceeds from the settlements for general corporate purposes.

14

Changes in Shareowners’ Equity - A summary of changes in shareowners’ equity was as follows (in millions):

Alliant Energy	Total Alliant Energy Common Equity
								Accumulated			Shares in			Cumulative
			Additional					Other			Deferred			Preferred
	Common		Paid-In		Retained			Comprehensive			Compensation			Stock		Total
	Stock		Capital		Earnings			Income (Loss)			Trust			of IPL		Equity
Three Months Ended June 30, 2020
Beginning balance, March 31, 2020		$2.5		$2,674.1		$2,833.7			$2.0			($9.9	)		$200.0		$5,702.4
Net income attributable to Alliant Energy common shareowners					134.4											134.4
Common stock dividends ($0.38 per share)					(94.6		)									(94.6		)
Shareowner Direct Plan issuances			6.4													6.4
Equity-based compensation plans and other			2.6								(0.3		)			2.3
Other comprehensive loss, net of tax								(2.6		)						(2.6		)
Ending balance, June 30, 2020		$2.5		$2,683.1		$2,873.5			($0.6	)		($10.2	)		$200.0		$5,748.3
Three Months Ended June 30, 2019
Beginning balance, March 31, 2019		$2.4		$2,100.0		$2,587.3			$2.4			($9.7	)		$200.0		$4,882.4
Net income attributable to Alliant Energy common shareowners					94.6											94.6
Common stock dividends ($0.355 per share)					(84.1		)									(84.1		)
Shareowner Direct Plan issuances			6.0													6.0
Equity-based compensation plans and other			2.4								(0.3		)			2.1
Other comprehensive loss, net of tax								(1.4		)						(1.4		)
Ending balance, June 30, 2019		$2.4		$2,108.4		$2,597.8			$1.0			($10.0	)		$200.0		$4,899.6

Alliant Energy	Total Alliant Energy Common Equity
								Accumulated			Shares in			Cumulative
			Additional					Other			Deferred			Preferred
	Common		Paid-In		Retained			Comprehensive			Compensation			Stock		Total
	Stock		Capital		Earnings			Income (Loss)			Trust			of IPL		Equity
Six Months Ended June 30, 2020
Beginning balance, December 31, 2019		$2.5		$2,445.9		$2,765.4			$1.3			($10.0	)		$200.0		$5,405.1
Net income attributable to Alliant Energy common shareowners					304.4											304.4
Common stock dividends ($0.76 per share)					(187.6		)									(187.6		)
Equity forward settlements and Shareowner Direct Plan issuances			234.8													234.8
Equity-based compensation plans and other			2.4								(0.2		)			2.2
Adoption of new accounting standard, net of tax (refer to Note 1(d))					(8.7		)									(8.7		)
Other comprehensive loss, net of tax								(1.9		)						(1.9		)
Ending balance, June 30, 2020		$2.5		$2,683.1		$2,873.5			($0.6	)		($10.2	)		$200.0		$5,748.3
Six Months Ended June 30, 2019
Beginning balance, December 31, 2018		$2.4		$2,045.5		$2,545.9			$1.7			($9.8	)		$200.0		$4,785.7
Net income attributable to Alliant Energy common shareowners					219.7											219.7
Common stock dividends ($0.71 per share)					(167.8		)									(167.8		)
Equity forward settlements and Shareowner Direct Plan issuances			60.6													60.6
Equity-based compensation plans and other			2.3								(0.2		)			2.1
Other comprehensive loss, net of tax								(0.7		)						(0.7		)
Ending balance, June 30, 2019		$2.4		$2,108.4		$2,597.8			$1.0			($10.0	)		$200.0		$4,899.6

15

IPL	Total IPL Common Equity
			Additional					Cumulative
	Common		Paid-In		Retained			Preferred		Total
	Stock		Capital		Earnings			Stock		Equity
Three Months Ended June 30, 2020
Beginning balance, March 31, 2020		$33.4		$2,447.8		$914.2			$200.0		$3,595.4
Net income available for common stock					59.8					59.8
Common stock dividends					(59.1		)			(59.1		)
Capital contributions from parent			75.0							75.0
Ending balance, June 30, 2020		$33.4		$2,522.8		$914.9			$200.0		$3,671.1
Three Months Ended June 30, 2019
Beginning balance, March 31, 2019		$33.4		$2,322.8		$785.8			$200.0		$3,342.0
Net income available for common stock					45.0					45.0
Common stock dividends					(41.9		)			(41.9		)
Ending balance, June 30, 2019		$33.4		$2,322.8		$788.9			$200.0		$3,345.1

IPL	Total IPL Common Equity
			Additional					Cumulative
	Common		Paid-In		Retained			Preferred		Total
	Stock		Capital		Earnings			Stock		Equity
Six Months Ended June 30, 2020
Beginning balance, December 31, 2019		$33.4		$2,347.8		$890.6			$200.0		$3,471.8
Net income available for common stock					142.4					142.4
Common stock dividends					(118.1		)			(118.1		)
Capital contributions from parent			175.0							175.0
Ending balance, June 30, 2020		$33.4		$2,522.8		$914.9			$200.0		$3,671.1
Six Months Ended June 30, 2019
Beginning balance, December 31, 2018		$33.4		$2,222.8		$774.5			$200.0		$3,230.7
Net income available for common stock					98.3					98.3
Common stock dividends					(83.9		)			(83.9		)
Capital contributions from parent			100.0							100.0
Ending balance, June 30, 2019		$33.4		$2,322.8		$788.9			$200.0		$3,345.1

WPL			Additional					Total
	Common		Paid-In		Retained			Common
	Stock		Capital		Earnings			Equity
Three Months Ended June 30, 2020
Beginning balance, March 31, 2020		$66.2		$1,459.0		$910.9			$2,436.1
Net income					57.6			57.6
Common stock dividends					(41.9		)	(41.9		)
Ending balance, June 30, 2020		$66.2		$1,459.0		$926.6			$2,451.8
Three Months Ended June 30, 2019
Beginning balance, March 31, 2019		$66.2		$1,309.0		$804.0			$2,179.2
Net income					42.0			42.0
Common stock dividends					(36.0		)	(36.0		)
Ending balance, June 30, 2019		$66.2		$1,309.0		$810.0			$2,185.2

16

WPL			Additional					Total
	Common		Paid-In		Retained			Common
	Stock		Capital		Earnings			Equity
Six Months Ended June 30, 2020
Beginning balance, December 31, 2019		$66.2		$1,434.0		$863.4			$2,363.6
Net income					147.2			147.2
Common stock dividends					(84.0		)	(84.0		)
Capital contributions from parent			25.0					25.0
Ending balance, June 30, 2020		$66.2		$1,459.0		$926.6			$2,451.8
Six Months Ended June 30, 2019
Beginning balance, December 31, 2018		$66.2		$1,309.0		$774.3			$2,149.5
Net income					107.7			107.7
Common stock dividends					(72.0		)	(72.0		)
Ending balance, June 30, 2019		$66.2		$1,309.0		$810.0			$2,185.2

NOTE 6. DEBT

NOTE 6(a) Short-term Debt - Information regarding Alliant Energy’s, IPL’s and WPL’s commercial paper, and Alliant Energy’s and WPL’s borrowings under the single credit facility, which currently expires in August 2023, classified as short-term debt was as follows (dollars in millions):

June 30, 2020	Alliant Energy	IPL	WPL
Amount outstanding	$185.4	$—	$37.9
Weighted average interest rates	0.3%	N/A	0.2%
Available credit facility capacity	$814.6	$250.0	$262.1

	Alliant Energy		IPL		WPL
Three Months Ended June 30	2020	2019	2020	2019	2020	2019
Maximum amount outstanding (based on daily outstanding balances)	$270.5	$590.2	$8.4	$—	$182.0	$193.3
Average amount outstanding (based on daily outstanding balances)	$121.2	$531.7	$0.4	$—	$8.7	$141.6
Weighted average interest rates	0.5%	2.7%	0.5%	N/A	0.5%	2.5%
Six Months Ended June 30
Maximum amount outstanding (based on daily outstanding balances)	$462.5	$600.6	$8.4	$50.4	$212.0	$195.1
Average amount outstanding (based on daily outstanding balances)	$251.8	$515.4	$0.2	$0.3	$87.9	$139.8
Weighted average interest rates	1.5%	2.7%	0.5%	2.8%	1.7%	2.5%

NOTE 6(b) Long-term Debt - In March 2020, AEF entered into a $300 million variable rate (1% as of June 30, 2020) term loan credit agreement (with Alliant Energy as guarantor) and used the borrowings under this agreement to retire its $300 million variable rate term loan credit agreement that would have expired in April 2020. AEF’s current term loan credit agreement expires in March 2022 and includes substantially the same financial covenants that are included in Alliant Energy’s credit facility agreement.

In April 2020, WPL issued $350 million of 3.65% debentures due 2050. The net proceeds from the issuance were used by WPL to reduce borrowings under the single credit facility and for general corporate purposes. In June 2020, WPL retired its $150 million 4.6% debentures.

In June 2020, IPL issued $400 million of 2.3% senior debentures due 2030. The net proceeds from the issuance were used by IPL to retire its $200 million 3.65% senior debentures that would have matured in September 2020 and for general corporate purposes.

17

NOTE 7. REVENUES

Disaggregation of revenues from contracts with customers, which correlates to revenues for each reportable segment, was as follows (in millions):

	Alliant Energy				IPL				WPL
Three Months Ended June 30	2020		2019		2020		2019		2020		2019
Electric Utility:
Retail - residential		$249.7		$233.3		$135.3		$125.9		$114.4		$107.4
Retail - commercial	164.0		171.3		109.0		111.4		55.0		59.9
Retail - industrial	197.3		214.2		114.3		118.4		83.0		95.8
Wholesale	39.1		41.0		13.0		14.6		26.1		26.4
Bulk power and other	25.1		31.4		16.8		22.0		8.3		9.4
Total Electric Utility	675.2		691.2		388.4		392.3		286.8		298.9
Gas Utility:
Retail - residential	33.6		35.2		18.5		20.0		15.1		15.2
Retail - commercial	14.7		16.1		8.3		8.8		6.4		7.3
Retail - industrial	1.7		2.0		1.3		1.6		0.4		0.4
Transportation/other	8.9		11.9		5.8		8.0		3.1		3.9
Total Gas Utility	58.9		65.2		33.9		38.4		25.0		26.8
Other Utility:
Steam	8.6		9.2		8.6		9.2		—		—
Other utility	1.5		1.7		1.0		1.3		0.5		0.4
Total Other Utility	10.1		10.9		9.6		10.5		0.5		0.4
Non-Utility and Other:
Transportation and other	18.9		22.9		—		—		—		—
Total Non-Utility and Other	18.9		22.9		—		—		—		—
Total revenues		$763.1		$790.2		$431.9		$441.2		$312.3		$326.1

	Alliant Energy				IPL				WPL
Six Months Ended June 30	2020		2019		2020		2019		2020		2019
Electric Utility:
Retail - residential		$516.5		$508.0		$282.7		$273.4		$233.8		$234.6
Retail - commercial	346.3		352.4		228.7		228.0		117.6		124.4
Retail - industrial	407.2		422.9		235.5		234.5		171.7		188.4
Wholesale	80.0		87.5		27.4		31.5		52.6		56.0
Bulk power and other	55.5		63.8		38.9		44.7		16.6		19.1
Total Electric Utility	1,405.5		1,434.6		813.2		812.1		592.3		622.5
Gas Utility:
Retail - residential	124.1		167.0		67.3		97.9		56.8		69.1
Retail - commercial	60.4		79.7		32.4		43.6		28.0		36.1
Retail - industrial	5.9		7.4		3.6		4.8		2.3		2.6
Transportation/other	20.7		26.9		13.6		16.7		7.1		10.2
Total Gas Utility	211.1		281.0		116.9		163.0		94.2		118.0
Other Utility:
Steam	18.6		17.6		18.6		17.6		—		—
Other utility	3.1		4.4		2.1		3.6		1.0		0.8
Total Other Utility	21.7		22.0		20.7		21.2		1.0		0.8
Non-Utility and Other:
Transportation and other	40.5		39.8		—		—		—		—
Total Non-Utility and Other	40.5		39.8		—		—		—		—
Total revenues		$1,678.8		$1,777.4		$950.8		$996.3		$687.5		$741.3

NOTE 8. INCOME TAXES

Income Tax Rates - Overall effective income tax rates, which were computed by dividing income tax expense (benefit) by income before income taxes, were as follows. The effective income tax rates were different than the federal statutory rate primarily due to state income taxes, production tax credits, amortization of excess deferred taxes and the effect of rate-making on property-related differences. The decreases in overall effective income tax rates for the three and six months ended June 30, 2020 compared to the same periods in 2019 were primarily due to increases in production tax credits as a result of increased wind production in 2020 and increased amortization of excess deferred taxes primarily at WPL, which were used to offset increases in WPL’s 2020 increased revenue requirements.

18

	Alliant Energy				IPL				WPL
	Three Months		Six Months		Three Months		Six Months		Three Months		Six Months
	2020	2019	2020	2019	2020	2019	2020	2019	2020	2019	2020	2019
Overall income tax rate	(6.5%)	10.3%	(9.6%)	10.5%	(6.5%)	3.8%	(13.8%)	3.7%	(8.5%)	15.5%	(9.4%)	17.2%

Deferred Tax Assets and Liabilities -

Carryforwards - At June 30, 2020, carryforwards and expiration dates were estimated as follows (in millions):

	Range of Expiration Dates	Alliant Energy		IPL		WPL
Federal net operating losses	2037		$299		$276		$3
State net operating losses	2020-2040	595		9		2
Federal tax credits	2022-2040	403		212		170

NOTE 9. BENEFIT PLANS

NOTE 9(a) Pension and OPEB Plans -

Net Periodic Benefit Costs - The components of net periodic benefit costs for sponsored defined benefit pension and OPEB plans for the three and six months ended June 30 are included below (in millions). For IPL and WPL, amounts represent those for their plan participants covered under plans they sponsor, as well as amounts directly assigned to them related to certain participants in the Alliant Energy and Corporate Services sponsored plans.

	Defined Benefit Pension Plans												OPEB Plans
	Three Months						Six Months						Three Months						Six Months
Alliant Energy	2020			2019			2020			2019			2020			2019			2020			2019
Service cost		$2.7			$2.4			$5.4			$4.8			$0.9			$0.9			$1.7			$1.7
Interest cost	10.8			12.4			21.6			24.9			1.7			2.1			3.5			4.2
Expected return on plan assets	(17.5		)	(15.0		)	(34.9		)	(30.0		)	(1.4		)	(1.3		)	(2.7		)	(2.5		)
Amortization of prior service credit	(0.1		)	(0.1		)	(0.3		)	(0.3		)	—			(0.1		)	—			(0.1		)
Amortization of actuarial loss	8.6			9.1			17.2			18.2			0.9			0.8			1.7			1.6
Settlement losses (a)	—			—			4.2			—			—			—			—			—
		$4.5			$8.8			$13.2			$17.6			$2.1			$2.4			$4.2			$4.9

	Defined Benefit Pension Plans												OPEB Plans
	Three Months						Six Months						Three Months						Six Months
IPL	2020			2019			2020			2019			2020			2019			2020			2019
Service cost		$1.7			$1.5			$3.4			$3.0			$0.4			$0.4			$0.7			$0.7
Interest cost	5.0			5.7			10.0			11.4			0.7			0.9			1.4			1.7
Expected return on plan assets	(8.2		)	(7.1		)	(16.3		)	(14.1		)	(0.9		)	(0.9		)	(1.9		)	(1.8		)
Amortization of prior service credit	—			—			(0.1		)	(0.1		)	—			—			—			—
Amortization of actuarial loss	3.7			4.0			7.4			7.9			0.2			0.3			0.5			0.7
		$2.2			$4.1			$4.4			$8.1			$0.4			$0.7			$0.7			$1.3

	Defined Benefit Pension Plans												OPEB Plans
	Three Months						Six Months						Three Months						Six Months
WPL	2020			2019			2020			2019			2020			2019			2020			2019
Service cost		$0.9			$0.8			$1.9			$1.7			$0.3			$0.3			$0.6			$0.6
Interest cost	4.7			5.4			9.4			10.8			0.7			0.9			1.4			1.7
Expected return on plan assets	(7.6		)	(6.6		)	(15.2		)	(13.1		)	(0.1		)	(0.2		)	(0.3		)	(0.3		)
Amortization of prior service credit	—			—			(0.1		)	(0.1		)	—			(0.1		)	—			(0.1		)
Amortization of actuarial loss	4.1			4.4			8.2			8.8			0.5			0.4			1.0			0.8
		$2.1			$4.0			$4.2			$8.1			$1.4			$1.3			$2.7			$2.7

(a) Settlement losses related to payments made to retired executives of Alliant Energy.

NOTE 9(b) Equity-based Compensation Plans - A summary of compensation expense, including amounts allocated to IPL and WPL, and the related income tax benefits recognized for share-based compensation awards for the three and six months ended June 30 was as follows (in millions):

19

	Alliant Energy								IPL								WPL
	Three Months				Six Months				Three Months				Six Months				Three Months				Six Months
	2020		2019		2020		2019		2020		2019		2020		2019		2020		2019		2020		2019
Compensation expense		$2.7		$3.4		$5.4		$8.1		$1.5		$1.9		$2.9		$4.5		$1.2		$1.4		$2.3		$3.2
Income tax benefits	0.8		1.0		1.5		2.3		0.4		0.5		0.8		1.3		0.3		0.4		0.6		0.9

As of June 30, 2020, Alliant Energy’s, IPL’s and WPL’s total unrecognized compensation cost related to share-based compensation awards was $9.9 million, $5.5 million and $4.1 million, respectively, which is expected to be recognized over a weighted average period of between 1 year and 2 years.

For the six months ended June 30, 2020, performance shares, performance restricted stock units and restricted stock units were granted to key employees as follows. These shares and units will be paid out in shares of common stock, and are therefore accounted for as equity awards. As of June 30, 2020, 228,207 shares were included in the calculation of diluted EPS related to the nonvested equity awards.

		Weighted Average
	Grants	Grant Date Fair Value
Performance shares	55,303		$64.04
Performance restricted stock units	55,303	59.47
Restricted stock units	60,284	59.49

NOTE 10. ASSET RETIREMENT OBLIGATIONS

A reconciliation of the changes in asset retirement obligations associated with long-lived assets for the six months ended June 30, 2020 is as follows (in millions):

	Alliant Energy			IPL
Balance, January 1		$196.3			$133.9
Revisions in estimated cash flows	0.9			—
Liabilities settled	(3.5		)	(2.8		)
Liabilities incurred (a)	27.6			27.6
Accretion expense	3.5			2.5
Balance, June 30		$224.8			$161.2

(a) During the six months ended June 30, 2020, Alliant Energy and IPL recognized additional asset retirement obligations related to IPL’s newly constructed Whispering Willow North and Golden Plains wind sites. The increases in asset retirement obligations resulted in corresponding increases in property, plant and equipment, net on the respective balance sheets.

NOTE 11. DERIVATIVE INSTRUMENTS

Commodity Derivatives -

Notional Amounts - As of June 30, 2020, gross notional amounts and settlement/delivery years related to outstanding swap contracts, option contracts, physical forward contracts and FTRs that were accounted for as commodity derivative instruments were as follows (units in thousands):

	FTRs		Natural Gas		Coal		Diesel Fuel
	MWhs	Years	Dths	Years	Tons	Years	Gallons	Years
Alliant Energy	21,455	2020-2021	234,304	2020-2028	4,482	2020-2021	6,804	2020-2022
IPL	8,978	2020-2021	123,308	2020-2028	1,834	2020-2021	—	—
WPL	12,477	2020-2021	110,996	2020-2027	2,648	2020-2021	6,804	2020-2022

Financial Statement Presentation - Derivative instruments are recorded at fair value each reporting date on the balance sheets as assets or liabilities as follows (in millions):

	Alliant Energy				IPL				WPL
	June 30, 2020		December 31, 2019		June 30, 2020		December 31, 2019		June 30, 2020		December 31, 2019
Current derivative assets		$27.9		$15.8		$22.5		$12.1		$5.4		$3.7
Non-current derivative assets	14.5		11.0		14.5		10.2		—		0.8
Current derivative liabilities	20.0		19.0		8.5		8.9		11.5		10.1
Non-current derivative liabilities	26.2		18.6		11.8		8.5		14.4		10.1

20

Credit Risk-related Contingent Features - Various agreements contain credit risk-related contingent features, including requirements to maintain certain credit ratings and/or limitations on liability positions under the agreements based on credit ratings. Certain of these agreements with credit risk-related contingency features are accounted for as derivative instruments. In the event of a material change in creditworthiness or if liability positions exceed certain contractual limits, credit support may need to be provided in the form of letters of credit or cash collateral up to the amount of exposure under the contracts, or the contracts may need to be unwound and underlying liability positions paid. At June 30, 2020 and December 31, 2019, the aggregate fair value of all derivative instruments with credit risk-related contingent features in a net liability position was not materially different than amounts that would be required to be posted as credit support to counterparties by Alliant Energy, IPL or WPL if the most restrictive credit risk-related contingent features for derivative agreements in a net liability position were triggered.

Balance Sheet Offsetting - The fair value amounts of derivative instruments subject to a master netting arrangement are not netted by counterparty on the balance sheets. However, if the fair value amounts of derivative instruments by counterparty were netted, amounts would not be materially different from gross amounts of derivative assets and derivative liabilities at June 30, 2020 and December 31, 2019. Fair value amounts recognized for the right to reclaim cash collateral (receivable) or the obligation to return cash collateral (payable) are not offset against fair value amounts recognized for derivative instruments executed with the same counterparty under the same master netting arrangement.

NOTE 12. FAIR VALUE MEASUREMENTS

Fair Value of Financial Instruments - The carrying amounts of current assets and current liabilities approximate fair value because of the short maturity of such financial instruments. Carrying amounts and related estimated fair values of other financial instruments were as follows (in millions):

Alliant Energy	June 30, 2020										December 31, 2019
			Fair Value										Fair Value
	Carrying		Level		Level		Level				Carrying		Level		Level		Level
	Amount		1		2		3		Total		Amount		1		2		3		Total
Assets:
Money market fund investments		$198.3		$198.3		$—		$—		$198.3		$5.4		$5.4		$—		$—		$5.4
Derivatives	42.4		—		4.6		37.8		42.4		26.8		—		4.8		22.0		26.8
Deferred proceeds	194.1		—		—		194.1		194.1		187.7		—		—		187.7		187.7
Liabilities:
Derivatives	46.2		—		44.8		1.4		46.2		37.6		—		36.8		0.8		37.6
Long-term debt (incl. current maturities)	6,579.8		—		7,768.1		1.7		7,769.8		6,190.2		—		6,917.9		2.0		6,919.9

IPL	June 30, 2020										December 31, 2019
			Fair Value										Fair Value
	Carrying		Level		Level		Level				Carrying		Level		Level		Level
	Amount		1		2		3		Total		Amount		1		2		3		Total
Assets:
Money market fund investments		$198.3		$198.3		$—		$—		$198.3		$5.4		$5.4		$—		$—		$5.4
Derivatives	37.0		—		3.3		33.7		37.0		22.3		—		2.8		19.5		22.3
Deferred proceeds	194.1		—		—		194.1		194.1		187.7		—		—		187.7		187.7
Liabilities:
Derivatives	20.3		—		19.0		1.3		20.3		17.4		—		16.6		0.8		17.4
Long-term debt (incl. current maturities)	3,343.5		—		3,924.7		—		3,924.7		3,147.3		—		3,489.1		—		3,489.1

WPL	June 30, 2020										December 31, 2019
			Fair Value										Fair Value
	Carrying		Level		Level		Level				Carrying		Level		Level		Level
	Amount		1		2		3		Total		Amount		1		2		3		Total
Assets:
Derivatives		$5.4		$—		$1.3		$4.1		$5.4		$4.5		$—		$2.0		$2.5		$4.5
Liabilities:
Derivatives	25.9		—		25.8		0.1		25.9		20.2		—		20.2		—		20.2
Long-term debt (incl. current maturities)	2,129.4		—		2,657.2		—		2,657.2		1,932.7		—		2,268.2		—		2,268.2

21

Information for Alliant Energy’s and IPL’s fair value measurements using significant unobservable inputs (Level 3 inputs) was as follows (in millions). Such amounts for WPL were not material.

Alliant Energy	Commodity Contract Derivative
	Assets and (Liabilities), net						Deferred Proceeds
Three Months Ended June 30	2020			2019			2020		2019
Beginning balance, April 1		$14.2			$0.4			$188.0		$178.3
Total net gains (losses) included in changes in net assets (realized/unrealized)	12.0			(0.1		)	—		—
Transfers out of Level 3	—			3.9			—		—
Purchases	14.0			13.8			—		—
Sales	(0.1		)	—			—		—
Settlements (a)	(3.7		)	(4.8		)	6.1		36.3
Ending balance, June 30		$36.4			$13.2			$194.1		$214.6
The amount of total net gains for the period included in changes in net assets attributable to the change in unrealized gains relating to assets and liabilities held at June 30		$11.9			$—			$—		$—

Alliant Energy	Commodity Contract Derivative
	Assets and (Liabilities), net						Deferred Proceeds
Six Months Ended June 30	2020			2019			2020		2019
Beginning balance, January 1		$21.2			$12.2			$187.7		$119.4
Total net gains (losses) included in changes in net assets (realized/unrealized)	9.0			(5.7		)	—		—
Transfers out of Level 3	—			3.9			—		—
Purchases	14.0			13.8			—		—
Sales	(0.2		)	(0.2		)	—		—
Settlements (a)	(7.6		)	(10.8		)	6.4		95.2
Ending balance, June 30		$36.4			$13.2			$194.1		$214.6
The amount of total net gains (losses) for the period included in changes in net assets attributable to the change in unrealized gains (losses) relating to assets and liabilities held at June 30		$9.0			($2.6	)		$—		$—

IPL	Commodity Contract Derivative
	Assets and (Liabilities), net						Deferred Proceeds
Three Months Ended June 30	2020			2019			2020		2019
Beginning balance, April 1		$13.5			$0.6			$188.0		$178.3
Total net gains included in changes in net assets (realized/unrealized)	11.0			0.4			—		—
Transfers out of Level 3	—			2.5			—		—
Purchases	10.7			9.5			—		—
Sales	(0.1		)	—			—		—
Settlements (a)	(2.7		)	(3.7		)	6.1		36.3
Ending balance, June 30		$32.4			$9.3			$194.1		$214.6
The amount of total net gains for the period included in changes in net assets attributable to the change in unrealized gains relating to assets and liabilities held at June 30		$11.0			$0.5			$—		$—

IPL	Commodity Contract Derivative
	Assets and (Liabilities), net						Deferred Proceeds
Six Months Ended June 30	2020			2019			2020		2019
Beginning balance, January 1		$18.7			$9.0			$187.7		$119.4
Total net gains (losses) included in changes in net assets (realized/unrealized)	8.8			(2.8		)	—		—
Transfers out of Level 3	—			2.5			—		—
Purchases	10.7			9.5			—		—
Sales	(0.2		)	(0.1		)	—		—
Settlements (a)	(5.6		)	(8.8		)	6.4		95.2
Ending balance, June 30		$32.4			$9.3			$194.1		$214.6
The amount of total net gains (losses) for the period included in changes in net assets attributable to the change in unrealized gains (losses) relating to assets and liabilities held at June 30		$8.8			($0.9	)		$—		$—

22

(a) Settlements related to deferred proceeds are due to the change in the carrying amount of receivables sold less the allowance for doubtful accounts associated with the receivables sold and cash amounts received from the receivables sold.

Commodity Contracts - The fair value of FTR and natural gas commodity contracts categorized as Level 3 was recognized as net derivative assets as follows (in millions):

	Alliant Energy				IPL				WPL
	Excluding FTRs		FTRs		Excluding FTRs		FTRs		Excluding FTRs		FTRs
June 30, 2020		$19.3		$17.1		$18.6		$13.8		$0.7		$3.3
December 31, 2019	14.6		6.6		13.6		5.1		1.0		1.5

NOTE 13. COMMITMENTS AND CONTINGENCIES

NOTE 13(a) Capital Purchase Commitments - Various contractual obligations contain minimum future commitments related to capital expenditures for certain construction projects. IPL’s projects include the expansion of wind generation. WPL’s projects include the expansion of wind and solar generation. At June 30, 2020, Alliant Energy’s, IPL’s and WPL’s minimum future commitments for these projects were $60 million, $8 million and $52 million, respectively.

NOTE 13(b) Other Purchase Commitments - Various commodity supply, transportation and storage contracts help meet obligations to provide electricity and natural gas to utility customers. In addition, there are various purchase commitments associated with other goods and services. At June 30, 2020, the related minimum future commitments were as follows (in millions):

	Alliant Energy		IPL		WPL
Purchased power (a)		$39		$38		$1
Natural gas	1,017		536		481
Coal (b)	101		62		39
Other (c)	113		54		28
		$1,270		$690		$549

(a) Includes payments required by PPAs for capacity rights and minimum quantities of MWhs required to be purchased. As a result of an amendment to shorten the term of the DAEC PPA, Alliant Energy’s and IPL’s amounts include minimum future commitments related to IPL’s purchase of capacity and the resulting energy from DAEC through September 2020, and do not include the September 2020 buyout payment of $110 million.

(b) Corporate Services has historically entered into system-wide coal contracts on behalf of IPL and WPL that include minimum future commitments. Such commitments were assigned to IPL and WPL based on information available as of June 30, 2020 regarding expected future usage, which is subject to change.

(c) Includes individual commitments incurred during the normal course of business that exceeded $1 million at June 30, 2020.

NOTE 13(c) Guarantees and Indemnifications -

Whiting Petroleum - Whiting Petroleum is an independent oil and gas company. In 2004, Alliant Energy sold its remaining interest in Whiting Petroleum. Alliant Energy Resources, LLC, as the successor to a predecessor entity that owned Whiting Petroleum, and a wholly-owned subsidiary of AEF, continues to guarantee the partnership obligations of an affiliate of Whiting Petroleum under multiple general partnership agreements in the oil and gas industry. Based on information made available to Alliant Energy by Whiting Petroleum, the Whiting Petroleum affiliate holds an approximate 6% share in the partnerships and currently known obligations include costs associated with the future abandonment of certain platforms off the coast of California and related onshore plant and equipment owned by the partnerships. The general partnerships were formed under California law, and Alliant Energy Resources, LLC’s guarantees, which do not include a maximum limit, apply to the Whiting Petroleum affiliate’s obligations and to the other partners. Alliant Energy Resources, LLC may be required to perform under the guarantees if the affiliate of Whiting Petroleum is unable to meet its partnership obligations.

As of June 30, 2020, the currently known partnership obligations are the abandonment obligations. The Whiting Petroleum affiliate’s share of these abandonment obligations on an undiscounted basis is estimated at $63 million as of June 30, 2020 based on information made available to Alliant Energy by Whiting Petroleum, and this represents Alliant Energy’s best estimate of the contingent obligations for potential future payments. Alliant Energy is not aware of any material liabilities related to these guarantees that it is probable that it will be obligated to pay; however, the new credit loss accounting standard adopted on January 1, 2020 requires recognition of a liability for expected credit losses related to the contingent obligations that are in the scope of these guarantees. With the adoption of this standard, Alliant Energy recorded a pre-tax $12 million cumulative effect adjustment to decrease the opening balance of retained earnings as of January 1, 2020. As a result of Whiting Petroleum’s deterioration in credit worthiness since January 1, 2020 likely from significantly depressed oil and gas prices and general market conditions, Alliant Energy currently expects credit exposure related to the guarantees and has recognized a $20 million credit loss liability as of June 30, 2020 related to the contingent obligations, which is recorded in

23

“Other liabilities” on Alliant Energy’s balance sheet. The incremental pre-tax change in the liability, $8 million, was recorded as a credit loss expense within Alliant Energy’s “Other operation and maintenance” expenses for the six months ended June 30, 2020. There was no incremental pre-tax change in the liability recorded for the three months ended June 30, 2020.

Non-utility Wind Farm in Oklahoma - In 2017, a wholly-owned subsidiary of AEF acquired a cash equity ownership interest in a non-utility wind farm located in Oklahoma. The wind farm provides electricity to a third-party under a long-term PPA. Alliant Energy provided a parent guarantee of its subsidiary’s indemnification obligations under the related operating agreement and PPA. Alliant Energy’s obligations under the operating agreement were $82 million as of June 30, 2020 and will reduce annually until expiring in July 2047. Alliant Energy’s obligations under the PPA are subject to a maximum limit of $17 million and expire in December 2031, subject to potential extension. Alliant Energy is not aware of any material liabilities related to this guarantee that it is probable that it will be obligated to pay and therefore has not recognized any material liabilities related to this guarantee as of June 30, 2020 and December 31, 2019.

IPL’s Minnesota Electric Distribution Assets - IPL provided indemnifications associated with the 2015 sale of its Minnesota electric distribution assets for losses resulting from potential breach of IPL’s representations, warranties and obligations under the sale agreement. Alliant Energy and IPL believe the likelihood of having to make any material cash payments under these indemnifications is remote. IPL has not recorded any material liabilities related to these indemnifications as of June 30, 2020 and December 31, 2019. The general terms of the indemnifications provided by IPL included a maximum limit of $17 million and expire in October 2020.

NOTE 13(d) Environmental Matters -

Manufactured Gas Plant (MGP) Sites - IPL and WPL have current or previous ownership interests in various sites that are previously associated with the production of gas for which IPL and WPL have, or may have in the future, liability for investigation, remediation and monitoring costs. IPL and WPL are working pursuant to the requirements of various federal and state agencies to investigate, mitigate, prevent and remediate, where necessary, the environmental impacts to property, including natural resources, at and around these former MGP sites in order to protect public health and the environment. At June 30, 2020, estimated future costs expected to be incurred for the investigation, remediation and monitoring of the MGP sites, as well as environmental liabilities recorded on the balance sheets for these sites, which are not discounted, were as follows (in millions). At June 30, 2020, such amounts for WPL were not material.

	Alliant Energy				IPL
Range of estimated future costs		$12	-	$29		$10	-	$24
Current and non-current environmental liabilities	16				13

IPL Consent Decree - In 2015, the U.S. District Court for the Northern District of Iowa approved a Consent Decree that IPL entered into with the EPA, the Sierra Club, the State of Iowa and Linn County in Iowa, thereby resolving potential Clean Air Act issues associated with emissions from IPL’s coal-fired generating facilities in Iowa. IPL has completed various requirements under the Consent Decree. IPL’s remaining requirements include fuel switching or retiring Burlington by December 31, 2021 and Prairie Creek Units 1 and 3 by December 31, 2025. Alliant Energy and IPL currently expect to recover material costs incurred by IPL related to compliance with the terms of the Consent Decree from IPL’s electric customers.

Other Environmental Contingencies - In addition to the environmental liabilities discussed above, various environmental rules are monitored that may have a significant impact on future operations. Several of these environmental rules are subject to legal challenges, reconsideration and/or other uncertainties. Given uncertainties regarding the outcome, timing and compliance plans for these environmental matters, the complete financial impact of each of these rules is not able to be determined; however, future capital investments and/or modifications to EGUs to comply with certain of these rules could be significant. Specific current, proposed or potential environmental matters include, among others: Effluent Limitation Guidelines, Coal Combustion Residuals Rule, and various legislation and EPA regulations to monitor and regulate the emission of greenhouse gases, including the Clean Air Act.

NOTE 13(e) Collective Bargaining Agreements - At June 30, 2020, employees covered by collective bargaining agreements represented 53%, 60% and 82% of total employees of Alliant Energy, IPL and WPL, respectively. On August 31, 2020, IPL’s collective bargaining agreement with International Brotherhood of Electrical Workers Local 204 (Cedar Rapids) expires, representing 18% and 44% of total employees of Alliant Energy and IPL, respectively. While the process to renew the agreement is underway and a tentative agreement has been reached, Alliant Energy and IPL are unable to predict the outcome.

24

NOTE 13(f) MISO Transmission Owner Return on Equity Complaints - A group of MISO cooperative and municipal utilities previously filed complaints with FERC requesting a reduction to the base return on equity used by MISO transmission owners, including ITC Midwest LLC and ATC. The first complaint covered the period from November 12, 2013 through February 11, 2015. In 2017, IPL and WPL received refunds related to the first complaint period, which were subsequently refunded to their retail and wholesale customers. The second complaint covered the period from February 12, 2015 through May 11, 2016. In November 2019, FERC issued an order on the previously filed complaints and reduced the base return on equity used by the MISO transmission owners to 9.88% effective for the first complaint period and subsequent to September 28, 2016. The November 2019 FERC order also dismissed the second complaint; therefore, FERC did not direct refunds to be made for that complaint. In May 2020, FERC issued an order in response to various rehearing requests and increased the base return on equity used by the MISO transmission owners from 9.88% to 10.02% for the first complaint period and subsequent to September 28, 2016, which reduces the refunds originally anticipated to be received by IPL and WPL as a result of FERC’s November 2019 order.

In the second quarter of 2020, IPL and WPL received $10 million and $3 million, respectively, in refunds related to the November 2019 FERC order. Additional refunds are currently expected to be issued; however, as a result of the May 2020 FERC order, timing is uncertain. IPL currently expects that all refunds will be returned to its retail electric customers after refund amounts and timing are known and a refund plan is approved by the IUB. WPL proposed to retain the refunds as part of WPL’s application with the PSCW to maintain its current retail electric base rates through the end of 2021. WPL currently expects that any refunds not utilized to maintain base rates would be returned to its customers in WPL’s next retail electric rate review proceeding. Any further changes in FERC’s decisions may have an impact on Alliant Energy’s share of ATC’s future earnings and customer costs.

NOTE 14. SEGMENTS OF BUSINESS

Certain financial information relating to Alliant Energy’s, IPL’s and WPL’s business segments is as follows. Intersegment revenues were not material to their respective operations.

Alliant Energy									ATC Holdings,		Alliant
	Utility								Non-Utility,		Energy
	Electric		Gas		Other		Total		Parent and Other		Consolidated
	(in millions)
Three Months Ended June 30, 2020
Revenues		$675.2		$58.9		$10.1		$744.2		$18.9		$763.1
Operating income	152.1		7.1		1.2		160.4		7.7		168.1
Net income attributable to Alliant Energy common shareowners							117.4		17.0		134.4
Three Months Ended June 30, 2019
Revenues		$691.2		$65.2		$10.9		$767.3		$22.9		$790.2
Operating income	132.9		7.2		1.4		141.5		8.3		149.8
Net income attributable to Alliant Energy common shareowners							87.0		7.6		94.6

Alliant Energy									ATC Holdings,		Alliant
	Utility								Non-Utility,		Energy
	Electric		Gas		Other		Total		Parent and Other		Consolidated
	(in millions)
Six Months Ended June 30, 2020
Revenues		$1,405.5		$211.1		$21.7		$1,638.3		$40.5		$1,678.8
Operating income	298.3		48.7		3.9		350.9		5.5		356.4
Net income attributable to Alliant Energy common shareowners							289.6		14.8		304.4
Six Months Ended June 30, 2019
Revenues		$1,434.6		$281.0		$22.0		$1,737.6		$39.8		$1,777.4
Operating income	259.3		52.4		1.4		313.1		13.5		326.6
Net income attributable to Alliant Energy common shareowners							206.0		13.7		219.7

25

IPL	Electric		Gas		Other		Total
	(in millions)
Three Months Ended June 30, 2020
Revenues		$388.4		$33.9		$9.6		$431.9
Operating income	82.1		5.2		1.4		88.7
Net income available for common stock							59.8
Three Months Ended June 30, 2019
Revenues		$392.3		$38.4		$10.5		$441.2
Operating income	68.9		4.2		1.4		74.5
Net income available for common stock							45.0
Six Months Ended June 30, 2020
Revenues		$813.2		$116.9		$20.7		$950.8
Operating income	149.1		32.5		3.8		185.4
Net income available for common stock							142.4
Six Months Ended June 30, 2019
Revenues		$812.1		$163.0		$21.2		$996.3
Operating income	115.7		30.5		1.8		148.0
Net income available for common stock							98.3

WPL	Electric		Gas		Other			Total
	(in millions)
Three Months Ended June 30, 2020
Revenues		$286.8		$25.0		$0.5			$312.3
Operating income (loss)	70.0		1.9		(0.2		)	71.7
Net income								57.6
Three Months Ended June 30, 2019
Revenues		$298.9		$26.8		$0.4			$326.1
Operating income	64.0		3.0		—			67.0
Net income								42.0
Six Months Ended June 30, 2020
Revenues		$592.3		$94.2		$1.0			$687.5
Operating income	149.2		16.2		0.1			165.5
Net income								147.2
Six Months Ended June 30, 2019
Revenues		$622.5		$118.0		$0.8			$741.3
Operating income (loss)	143.6		21.9		(0.4		)	165.1
Net income								107.7

NOTE 15. RELATED PARTIES

Service Agreements - Pursuant to service agreements, IPL and WPL receive various administrative and general services from an affiliate, Corporate Services. These services are billed to IPL and WPL at cost based on expenses incurred by Corporate Services for the benefit of IPL and WPL, respectively. These costs consisted primarily of employee compensation and benefits, fees associated with various professional services, depreciation and amortization of property, plant and equipment, and a return on net assets. Corporate Services also acts as agent on behalf of IPL and WPL pursuant to the service agreements. As agent, Corporate Services enters into energy, capacity, ancillary services, and transmission sale and purchase transactions within MISO. Corporate Services assigns such sales and purchases among IPL and WPL based on statements received from MISO. The amounts billed for services provided, sales credited and purchases for the three and six months ended June 30 were as follows (in millions):

	IPL								WPL
	Three Months				Six Months				Three Months				Six Months
	2020		2019		2020		2019		2020		2019		2020		2019
Corporate Services billings		$44		$47		$81		$90		$35		$35		$67		$68
Sales credited	10		12		25		27		2		3		4		4
Purchases billed	57		74		138		158		20		29		40		59

Net intercompany payables to Corporate Services were as follows (in millions):

	IPL		WPL
	June 30, 2020	December 31, 2019	June 30, 2020	December 31, 2019
Net payables to Corporate Services	$93	$112	$65	$85

26

ATC - Pursuant to various agreements, WPL receives a range of transmission services from ATC. WPL provides operation, maintenance, and construction services to ATC. WPL and ATC also bill each other for use of shared facilities owned by each party. The related amounts billed between the parties for the three and six months ended June 30 were as follows (in millions):

	Three Months				Six Months
	2020		2019		2020		2019
ATC billings to WPL		$25		$27		$53		$54
WPL billings to ATC	3		3		6		7

WPL owed ATC net amounts of $9 million as of June 30, 2020 and $9 million as of December 31, 2019. In the second quarter of 2020, WPL received $46 million from ATC related to construction deposits WPL previously provided ATC for transmission network upgrades for the West Riverside Energy Center, which is recorded in “Other” in AEC’s and WPL’s cash flows from investing activities.

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

This MDA includes information relating to Alliant Energy, and IPL and WPL (collectively, the Utilities), as well as ATC Holdings, AEF and Corporate Services. Where appropriate, information relating to a specific entity has been segregated and labeled as such. The following discussion and analysis should be read in conjunction with the Financial Statements and the Notes included in this report, as well as the financial statements, notes and MDA included in the 2019 Form 10-K. Unless otherwise noted, all “per share” references in MDA refer to earnings per diluted share.

2020 HIGHLIGHTS

Key highlights since the filing of the 2019 Form 10-K include the following:

COVID-19:

The outbreak of COVID-19 has become a global pandemic and Alliant Energy’s service territories are not immune to the challenges presented by COVID-19. Despite these challenges, Alliant Energy, IPL and WPL continue to focus on providing the critical, reliable service their customers depend on, while emphasizing the health and welfare of their employees, customers and communities. Alliant Energy, IPL and WPL have not experienced significant impacts on their overall business operations, financial condition, results of operations or cash flows for the three and six months ended June 30, 2020; however, the degree to which the COVID-19 pandemic may impact such items in the future is currently unknown and will depend on future developments of the pandemic as well as possible additional actions by government and regulatory authorities. Alliant Energy has mitigated the impact of sales declines from COVID-19 by accelerating planned cost transformation activities. Actual and potential impacts from COVID-19 include, but are not limited to, the following:

Operational and Supply Chain Impacts - Alliant Energy has modified certain business practices to help ensure the health and safety of its employees, contractors, customers and vendors consistent with orders and best practices issued by government and regulatory authorities. For example, Alliant Energy implemented its business continuity and pandemic plans for critical items and services, including travel restrictions, physical distancing, working-from-home protocols, and rescheduling of planned EGU outages. Alliant Energy also temporarily suspended service disconnects, waived late payment fees for its customers, and modified reconnect service procedures to ensure continuity of service for customers unable to pay their bills and consistency with regulatory orders.

While Alliant Energy has not experienced any significant issues to-date, it continues to monitor potential disruptions or constraints in materials and supplies from key suppliers. In addition, Alliant Energy’s construction projects are currently progressing as planned with added safety protocols, and while it continues to monitor its supply chain, there have been no immediate disruptions. Currently, Alliant Energy expects its large renewable construction projects to be placed in service as previously planned to meet the timing requirements to qualify for the maximum renewable tax credits. In addition, Alliant Energy does not currently expect any material changes to its construction and acquisition expenditures plans disclosed in the 2019 Form 10-K resulting from COVID-19.

Alliant Energy has not experienced, and currently does not expect, an interruption in its ability to provide electric and natural gas services to its customers. Alliant Energy currently expects to incur incremental direct expenses related to certain of these operational changes and does expect them to have a material impact on its results of operations.

Customer Impacts - COVID-19 has resulted in various travel restrictions and closures of commercial spaces and industrial facilities in Alliant Energy’s service territories. While the total expected impact of COVID-19 on future sales is currently unknown, Alliant Energy has experienced higher electric residential sales and lower electric commercial and industrial sales since the outset of the pandemic, and this has continued through July 2020. For the second quarter of 2020 compared to the second quarter of 2019, Alliant Energy’s retail electric residential temperature-normalized sales increased 5%, and its retail electric commercial and industrial temperature-normalized sales decreased 9% in aggregate. While sales to retail electric

27

commercial and industrial customers started to rebound in June 2020 and July 2020, given the continued uncertainty of COVID-19 impacts on sales, Alliant Energy currently expects a slight reduction in temperature-normalized retail sales in 2020 compared to 2019. From a sensitivity perspective, Alliant Energy currently estimates that an annual 1% increase/decrease in sales for each customer type would result in corresponding annual impacts of $0.02 EPS for its retail electric residential customers, $0.01 EPS for its retail electric commercial customers and $0.01 EPS for its retail electric industrial customers.

Liquidity and Capital Resources Impacts - In response to the uncertainty of the impacts of COVID-19, Alliant Energy enhanced its liquidity position in the first quarter of 2020 by settling $222 million under the equity forward sale agreements and AEF accelerating the refinancing of its $300 million term-loan credit agreement that would have been due in April 2020. In March 2020 and April 2020, Alliant Energy and WPL borrowed under the single credit facility for a portion of their cash needs to obtain more favorable interest rates than available in the commercial paper market. This single credit facility also allows borrowing capacity to shift among Alliant Energy (at the parent company level), IPL and WPL as needed. In April 2020, WPL issued $350 million of debentures due 2050, and in June 2020, IPL issued $400 million of senior debentures due 2030. In June 2020, IPL and WPL retired $200 million and $150 million of long-term debt, respectively, and there are no other material long-term debt maturities in 2020 and 2021. In addition, IPL maintains a sales of accounts receivable program as an alternative financing source; however, if customer arrears were to exceed certain levels, IPL’s access to the program may be restricted.

Alliant Energy, IPL and WPL currently expect to maintain compliance with the financial covenants of the credit facility agreement, and Alliant Energy currently expects to maintain compliance with the financial covenants in AEF’s term loan credit agreement. In addition, Alliant Energy currently expects to have adequate liquidity to fulfill its contractual obligations, access to capital markets and continue with its planned quarterly dividend payments.

Credit Risk Impacts - Alliant Energy’s temporary suspension of service disconnects and waivers of late payment fees for its customers, as well as broad economic factors, may negatively impact its customers’ abilities to pay, which could increase customer arrears and bad debts, and negatively impact Alliant Energy’s cash flows from operations. Currently, Alliant Energy does not anticipate any material credit risk related to its commodity transactions. In addition, Alliant Energy recorded an $8 million credit loss charge in the first quarter of 2020 related to legacy guarantees associated with an affiliate of Whiting Petroleum, partly as a result of the increasing concerns and impacts from the pandemic on the depressed oil and gas prices.

Regulatory Impacts - In March 2020, WPL received authorization from the PSCW to defer certain incremental costs incurred resulting from COVID-19, including bad debt expenses and foregone revenues from late payment fees and deposits. In June 2020, IPL filed a proposal with the IUB for utilization of a regulatory asset account to track increased expenses and other financial impacts incurred after March 1, 2020 resulting from COVID-19. The recovery of any authorized deferrals will be addressed in future regulatory proceedings. For the three and six months ended June 30, 2020, such recorded amounts were not material.

Legislative Impacts - In March 2020, the Coronavirus Aid, Relief, and Economic Security Act (CARES Act) was enacted. The most significant provision of the CARES Act for Alliant Energy relates to an acceleration of refunds of existing alternative minimum tax credits to improve liquidity. In July 2020, Alliant Energy received $11 million of credits that otherwise would have been received in 2021 and 2022. Other provisions of the CARES Act that Alliant Energy is currently evaluating include deferral of 2020 remaining pension contributions and payroll taxes to 2021 and 2022. In addition, the CARES Act provides additional funding to the Low Income Home Energy Assistance Program, which assists certain of Alliant Energy’s customers with managing their energy costs. The CARES Act also provides financial support for certain of Alliant Energy’s small business customers.

Rate Matters:

• Final retail electric rates for IPL’s 2020 Forward-looking Test Period rate review were effective February 26, 2020. Effective with the implementation of final rates, IPL started to recover a return of and return on its new wind generation placed in service in 2019 and 2020 through the renewable energy rider.

• In May 2020, WPL filed an application with the PSCW to maintain its current retail electric and gas base rates, authorized return on common equity, regulatory capital structure and earnings sharing mechanism through the end of 2021. WPL’s proposal utilizes anticipated fuel-related cost savings in 2021 to offset the revenue requirement impacts of the Kossuth wind farm expected to be placed in service in late 2020. In addition, WPL’s proposal utilizes excess deferred tax benefits to partially offset the revenue requirement of the expansion of its gas distribution system in Western Wisconsin also expected to be placed in service in late 2020. WPL’s proposal also seeks additional flexibility to mitigate certain cost impacts outside of its control due to the COVID-19 pandemic if circumstances warrant.

• In the second quarter of 2020, pursuant to a June 2020 IUB order, IPL issued $42 million of credits to its retail electric customers through its transmission cost rider for amounts previously collected in rates.

• In July 2020, the PSCW issued a decision directing WPL to refund $12 million of 2019 fuel-related cost over-collections to its retail electric customers in September 2020.

Customer Investments:

• In March 2020, IPL completed the construction of the Golden Plains wind farm in Iowa (200 MW).

• In April 2020, WPL received authorization from the PSCW to expand its gas distribution system in Western Wisconsin, which is currently expected to be completed in 2020.

28

• In May 2020, WPL completed the construction of the natural gas-fired West Riverside Energy Center (730 MW).

• In May 2020, WPL filed a Certificate of Authority with the PSCW for approval to acquire, construct, own, and operate up to 675 MW of new solar generation, which is expected to qualify for 30% investment tax credits, in the following Wisconsin counties: Grant (200 MW in 2023), Sheboygan (150 MW in 2022), Wood (150 MW in 2022), Jefferson (75 MW in 2022), Richland (50 MW in 2022) and Rock (50 MW in 2023). WPL proposes to own and operate the solar projects through a tax equity partnership, with approximately 35% to 45% of the construction costs financed with capital from the tax equity partner, allowing WPL’s customers to share the costs of the solar projects with an investment partner for 10 years or less, while ensuring its customers receive energy, capacity, and renewable energy credit benefits from the projects. WPL would expect to purchase the tax equity partner’s interest in the solar projects within 10 years of operation, and then convert to a traditional ownership structure for the remainder of the useful life of the projects. WPL’s estimated portion of capital expenditures for the 675 MW of new solar generation, excluding allowance for funds used during construction, is currently expected to be approximately $885 million in aggregate ($25 million, $410 million, $370 million and $80 million in 2020 through 2023, respectively). Assuming 35% of the construction costs are financed by the tax equity partner, WPL would receive approximately $190 million and $110 million from the tax equity partner in 2022 and 2023, respectively. WPL requested to include $585 million in rate base, which reflects its portion of capital expenditures, less the amounts financed by the tax equity partner. The 675 MW of new solar generation would replace energy and capacity being eliminated with the planned retirement of the coal-fired Edgewater Generating Station (414 MW) by the end of 2022, which is subject to change depending on operational, regulatory, market and other factors.

• In July 2020, Alliant Energy announced it achieved its goal that 30% of its overall energy mix be from renewable resources and establishment of updated voluntary environmental-related goals based on its clean energy strategy. By 2030, Alliant Energy expects to reduce carbon dioxide emissions by 50% and water supply by 75% from 2005 levels from its owned fossil-fueled generation. By 2040, Alliant Energy expects to eliminate all coal-fired EGUs from its generating fleet, and by 2050, seeks to achieve an aspirational goal of net-zero carbon dioxide emissions from the electricity it generates. Future updates to sustainable energy plans and attaining these goals will depend on future economic developments, evolving energy technologies and emerging trends in Alliant Energy’s service territories.

Financings:

• In March 2020, Alliant Energy settled $222 million under the equity forward sale agreements by delivering 4,275,127 shares of newly issued Alliant Energy common stock at a weighted average forward sale price of $51.98 per share.

• In March 2020, AEF entered into a $300 million variable rate (1% as of June 30, 2020) term loan credit agreement (with Alliant Energy as guarantor), which expires in March 2022, and used the borrowings under this agreement to retire its $300 million variable rate term loan credit agreement that would have expired in April 2020.

• In April 2020, WPL issued $350 million of 3.65% debentures due 2050. The net proceeds from the issuance were used by WPL to reduce borrowings under the single credit facility, which currently expires in August 2023, and for general corporate purposes. In June 2020, WPL retired its $150 million 4.6% debentures.

• In June 2020, IPL issued $400 million of 2.3% senior debentures due 2030. The net proceeds from the issuance were used by IPL to retire its $200 million 3.65% senior debentures that would have matured in September 2020 and for general corporate purposes.

RESULTS OF OPERATIONS

Results of operations include financial information prepared in accordance with GAAP as well as utility electric margins and utility gas margins, which are not measures of financial performance under GAAP. Utility electric margins are defined as electric revenues less electric production fuel, purchased power and electric transmission service expenses. Utility gas margins are defined as gas revenues less cost of gas sold. Utility electric margins and utility gas margins are non-GAAP financial measures because they exclude other utility and non-utility revenues, other operation and maintenance expenses, depreciation and amortization expenses, and taxes other than income tax expense.

Management believes that utility electric and gas margins provide a meaningful basis for evaluating and managing utility operations since electric production fuel, purchased power and electric transmission service expenses and cost of gas sold are generally passed through to customers, and therefore, result in changes to electric and gas revenues that are comparable to changes in such expenses. The presentation of utility electric and gas margins herein is intended to provide supplemental information for investors regarding operating performance. These utility electric and gas margins may not be comparable to how other entities define utility electric and gas margin. Furthermore, these measures are not intended to replace operating income as determined in accordance with GAAP as an indicator of operating performance.

Additionally, the table below includes EPS for Utilities and Corporate Services, ATC Holdings, and Non-utility and Parent, which are non-GAAP financial measures. Alliant Energy believes these non-GAAP financial measures are useful to investors because they facilitate an understanding of segment performance and trends, and provide additional information about Alliant Energy’s operations on a basis consistent with the measures that management uses to manage its operations and evaluate its performance.

29

Financial Results Overview - Alliant Energy’s net income and EPS attributable to Alliant Energy common shareowners for the three months ended June 30 were as follows (dollars in millions, except per share amounts):

	2020				2019
	Income		EPS		Income (Loss)			EPS
Utilities and Corporate Services		$120.8		$0.48		$90.1			$0.38
ATC Holdings	10.2		0.04		7.5			0.03
Non-utility and Parent	3.4		0.02		(3.0		)	(0.01		)
Alliant Energy Consolidated		$134.4		$0.54		$94.6			$0.40

Alliant Energy’s Utilities and Corporate Services net income increased by $31 million for the three-month period, primarily due to higher earnings resulting from IPL’s and WPL’s increasing rate base, as well as favorable temperature impacts on electric sales for the quarter. These items were partially offset by higher depreciation expense and timing of income taxes.

Alliant Energy’s Non-utility and Parent net income increased by $6 million for the three-month period primarily due to the timing of income taxes.

For the three and six months ended June 30, operating income and a reconciliation of utility electric and gas margins to the most directly comparable GAAP measure, operating income, was as follows (in millions):

	Alliant Energy						IPL						WPL
Three Months	2020			2019			2020			2019			2020			2019
Operating income		$168.1			$149.8			$88.7			$74.5			$71.7			$67.0
Electric utility revenues		$675.2			$691.2			$388.4			$392.3			$286.8			$298.9
Electric production fuel and purchased power expenses	(163.5		)	(164.8		)	(96.0		)	(83.3		)	(67.5		)	(81.5		)
Electric transmission service expense	(71.6		)	(112.4		)	(34.0		)	(77.4		)	(37.6		)	(35.0		)
Utility Electric Margin (non-GAAP)	440.1			414.0			258.4			231.6			181.7			182.4
Gas utility revenues	58.9			65.2			33.9			38.4			25.0			26.8
Cost of gas sold	(20.9		)	(20.4		)	(12.4		)	(10.8		)	(8.5		)	(9.6		)
Utility Gas Margin (non-GAAP)	38.0			44.8			21.5			27.6			16.5			17.2
Other utility revenues	10.1			10.9			9.6			10.5			0.5			0.4
Non-utility revenues	18.9			22.9			—			—			—			—
Other operation and maintenance expenses	(159.8		)	(172.3		)	(97.5		)	(97.4		)	(53.2		)	(62.4		)
Depreciation and amortization expenses	(152.1		)	(142.9		)	(88.7		)	(82.6		)	(62.0		)	(59.1		)
Taxes other than income tax expense	(27.1		)	(27.6		)	(14.6		)	(15.2		)	(11.8		)	(11.5		)
Operating income		$168.1			$149.8			$88.7			$74.5			$71.7			$67.0

	Alliant Energy						IPL						WPL
Six Months	2020			2019			2020			2019			2020			2019
Operating income		$356.4			$326.6			$185.4			$148.0			$165.5			$165.1
Electric utility revenues		$1,405.5			$1,434.6			$813.2			$812.1			$592.3			$622.5
Electric production fuel and purchased power expenses	(347.6		)	(383.2		)	(202.2		)	(212.2		)	(145.4		)	(171.0		)
Electric transmission service expense	(193.8		)	(235.4		)	(118.5		)	(165.1		)	(75.3		)	(70.3		)
Utility Electric Margin (non-GAAP)	864.1			816.0			492.5			434.8			371.6			381.2
Gas utility revenues	211.1			281.0			116.9			163.0			94.2			118.0
Cost of gas sold	(105.9		)	(142.0		)	(56.6		)	(74.1		)	(49.3		)	(67.9		)
Utility Gas Margin (non-GAAP)	105.2			139.0			60.3			88.9			44.9			50.1
Other utility revenues	21.7			22.0			20.7			21.2			1.0			0.8
Non-utility revenues	40.5			39.8			—			—			—			—
Other operation and maintenance expenses	(322.0		)	(353.5		)	(184.1		)	(205.4		)	(107.4		)	(125.9		)
Depreciation and amortization expenses	(298.4		)	(279.8		)	(174.6		)	(159.7		)	(121.1		)	(117.7		)
Taxes other than income tax expense	(54.7		)	(56.9		)	(29.4		)	(31.8		)	(23.5		)	(23.4		)
Operating income		$356.4			$326.6			$185.4			$148.0			$165.5			$165.1

30

Operating Income Variances - Variances between periods in operating income for the three and six months ended June 30, 2020 compared to the same periods in 2019 were as follows (in millions):

	Three Months									Six Months
	Alliant Energy			IPL			WPL			Alliant Energy			IPL			WPL
Total higher (lower) utility electric margin variance (Refer to details below)		$26			$27			($1	)		$48			$58			($10	)
Total lower utility gas margin variance (Refer to details below)	(7		)	(6		)	(1		)	(34		)	(29		)	(5		)
Total lower other operation and maintenance expenses variance (Refer to details below)	13			—			9			32			21			19
Higher depreciation and amortization expense primarily due to additional plant in service in 2019 and 2020, including IPL’s new wind generation and WPL’s West Riverside Energy Center	(9		)	(6		)	(3		)	(19		)	(15		)	(3		)
Other	(5		)	(1		)	1			3			2			(1		)
		$18			$14			$5			$30			$37			$—

Electric and Gas Revenues and Sales Summary - Electric and gas revenues (in millions), and MWh and Dth sales (in thousands), for the three and six months ended June 30 were as follows:

Alliant Energy	Electric						Gas
	Revenues				MWhs Sold		Revenues				Dths Sold
	2020		2019		2020	2019	2020		2019		2020	2019
Three Months
Retail		$611.0		$618.8	5,609	5,815		$50.0		$53.3	7,023	7,037
Sales for resale	50.9		55.6		1,630	1,408	N/A		N/A		N/A	N/A
Transportation/Other	13.3		16.8		18	22	8.9		11.9		25,888	21,423
		$675.2		$691.2	7,257	7,245		$58.9		$65.2	32,911	28,460
Six Months
Retail		$1,270.0		$1,283.3	11,734	12,167		$190.4		$254.1	29,045	33,416
Sales for resale	108.6		119.1		3,509	2,832	N/A		N/A		N/A	N/A
Transportation/Other	26.9		32.2		36	48	20.7		26.9		54,704	46,793
		$1,405.5		$1,434.6	15,279	15,047		$211.1		$281.0	83,749	80,209

IPL	Electric						Gas
	Revenues				MWhs Sold		Revenues				Dths Sold
	2020		2019		2020	2019	2020		2019		2020	2019
Three Months
Retail		$358.6		$355.7	3,189	3,250		$28.1		$30.4	3,456	3,373
Sales for resale	22.4		25.9		1,074	900	N/A		N/A		N/A	N/A
Transportation/Other	7.4		10.7		8	9	5.8		8.0		8,813	8,820
		$388.4		$392.3	4,271	4,159		$33.9		$38.4	12,269	12,193
Six Months
Retail		$746.9		$735.9	6,671	6,879		$103.3		$146.3	15,077	17,366
Sales for resale	50.3		57.9		2,325	1,827	N/A		N/A		N/A	N/A
Transportation/Other	16.0		18.3		18	18	13.6		16.7		20,107	19,827
		$813.2		$812.1	9,014	8,724		$116.9		$163.0	35,184	37,193

WPL	Electric						Gas
	Revenues				MWhs Sold		Revenues				Dths Sold
	2020		2019		2020	2019	2020		2019		2020	2019
Three Months
Retail		$252.4		$263.1	2,420	2,565		$21.9		$22.9	3,567	3,664
Sales for resale	28.5		29.7		556	508	N/A		N/A		N/A	N/A
Transportation/Other	5.9		6.1		10	13	3.1		3.9		17,075	12,603
		$286.8		$298.9	2,986	3,086		$25.0		$26.8	20,642	16,267
Six Months
Retail		$523.1		$547.4	5,063	5,288		$87.1		$107.8	13,968	16,050
Sales for resale	58.3		61.2		1,184	1,005	N/A		N/A		N/A	N/A
Transportation/Other	10.9		13.9		18	30	7.1		10.2		34,597	26,966
		$592.3		$622.5	6,265	6,323		$94.2		$118.0	48,565	43,016

31

Sales Trends and Temperatures - Alliant Energy’s retail electric sales volumes decreased 4% for the three months ended June 30, 2020 compared to the same period in 2019 primarily due to the impacts from COVID-19, partially offset by favorable temperature impacts during the second quarter of 2020 in Alliant Energy’s service territories. Alliant Energy’s retail gas sales volumes remained unchanged for the three months ended June 30, 2020 compared to the same period in 2019 primarily due to favorable temperature impacts during the second quarter of 2020 in Alliant Energy’s service territories, offset by the impacts from COVID-19. Alliant Energy’s retail electric and gas sales volumes decreased 4% and 13% for the six months ended June 30, 2020 compared to the same period in 2019, respectively, primarily due to the impacts of COVID-19 and changes in temperatures in Alliant Energy’s service territories. The six-month decrease in sales was partially offset by an extra day of sales during the first quarter of 2020 due to leap year. For the three and six months ended June 30, 2020, COVID-19 impacts on sales volumes resulted in increases for retail electric residential sales volumes and decreases for retail electric commercial and industrial sales.

Estimated increases (decreases) to electric and gas margins from the impacts of temperatures for the three and six months ended June 30 were as follows (in millions):

	Electric Margins															Gas Margins
	Three Months							Six Months								Three Months						Six Months
	2020		2019			Change		2020			2019		Change			2020		2019		Change		2020			2019		Change
IPL		$2		($3	)		$5		($1	)		$3		($4	)		$2		$1		$1		$—			$4		($4	)
WPL	3		(4		)	7		—			—		—			—		—		—		(1		)	2		(3		)
Total Alliant Energy		$5		($7	)		$12		($1	)		$3		($4	)		$2		$1		$1		($1	)		$6		($7	)

Utility Electric Margin Variances - The following items contributed to increased (decreased) utility electric margins for the three and six months ended June 30, 2020 compared to the same periods in 2019 as follows (in millions):

	Three Months									Six Months
	Alliant Energy			IPL			WPL			Alliant Energy			IPL			WPL
Impact of IPL’s retail electric final and interim rate increases effective February 2020 and April 2019, respectively (a)		$17			$17			$—			$47			$47			$—
Higher revenues at IPL due to credits on customers’ bills in 2019 related to production tax credits through the fuel-related cost recovery mechanism (offset by changes in income tax)	5			5			—			10			10			—
Higher revenues at IPL due to changes in electric tax benefit rider credits on customers’ bills (offset by changes in income tax)	1			1			—			6			6			—
Changes in timing of collection of electric transmission service costs at WPL	(3		)	—			(3		)	(5		)	—			(5		)
Estimated changes in sales volumes caused by temperatures	12			5			7			(4		)	(4		)	—
Other (includes lower temperature-normalized sales primarily due to COVID-19 impacts)	(6		)	(1		)	(5		)	(6		)	(1		)	(5		)
		$26			$27			($1	)		$48			$58			($10	)

(a) IPL’s interim retail electric base rate increase was effective April 1, 2019 and final retail electric base rate increase was effective February 26, 2020. Effective with final rates, the recovery of, and return on, IPL’s new wind generation placed in service in 2019 and 2020 is provided through the renewable energy rider. Both interim and final rate increases include a reduction for anticipated production tax credits for IPL’s new wind generation. This reduction is expected to be offset by a reduction in income tax expense resulting from production tax credits recognized from this new wind generation.

Utility Gas Margin Variances - The following items contributed to increased (decreased) utility gas margins for the three and six months ended June 30, 2020 compared to the same periods in 2019 as follows (in millions):

	Three Months									Six Months
	Alliant Energy			IPL			WPL			Alliant Energy			IPL			WPL
Lower revenues at IPL related to changes in recovery amounts for energy efficiency costs through the energy efficiency rider (mostly offset by changes in energy efficiency expense)		($5	)		($5	)		$—			($27	)		($27	)		$—
Estimated changes in sales volumes caused by temperatures	1			1			—			(7		)	(4		)	(3		)
Impact of IPL’s retail gas rate increase effective January 2020	1			1			—			7			7			—
Other (includes lower temperature-normalized sales primarily due to COVID-19 impacts)	(4		)	(3		)	(1		)	(7		)	(5		)	(2		)
		($7	)		($6	)		($1	)		($34	)		($29	)		($5	)

32

Other Operation and Maintenance Expenses Variances - The following items contributed to (increased) decreased other operation and maintenance expenses for the three and six months ended June 30, 2020 compared to the same periods in 2019 as follows (in millions):

	Three Months								Six Months
	Alliant Energy			IPL			WPL		Alliant Energy			IPL			WPL
Lower energy efficiency expense at IPL (primarily offset by lower gas revenues)		$6			$6			$—		$26			$26			$—
Lower generation operation and maintenance expenses	8			4			4		9			2			7
Credit loss charge related to guarantees for an affiliate of Whiting Petroleum (Refer to Note 13(c))	—			—			—		(8		)	—			—
Other	(1		)	(10		)	5		5			(7		)	12
		$13			$—			$9		$32			$21			$19

Other Income and Deductions Variances - The following items contributed to (increased) decreased other income and deductions for the three and six months ended June 30, 2020 compared to the same periods in 2019 as follows (in millions):

	Three Months									Six Months
	Alliant Energy			IPL			WPL			Alliant Energy			IPL			WPL
Higher interest expense primarily due to higher average outstanding long-term debt balances		$—			($3	)		($1	)		($3	)		($8	)		($1	)
Higher (lower) allowance for funds used during construction primarily due to changes in construction work in progress balances related to IPL’s new wind generation and WPL’s West Riverside Energy Center and new wind generation	(3		)	(2		)	(1		)	(6		)	(8		)	3
Other (Refer to Note 4 for details of increased income from unconsolidated equity investments)	5			—			1			11			1			2
		$2			($5	)		($1	)		$2			($15	)		$4

Income Taxes - Alliant Energy’s overall effective income tax rates were (6.5)% and 10.3% for the three months ended June 30, 2020 and 2019, and (9.6)% and 10.5% for the six months ended June 30, 2020 and 2019, respectively. The decrease in effective income tax rates is primarily due to increases in production tax credits as a result of increased wind production in 2020 and increases of amortization of excess deferred taxes primarily at WPL. WPL’s 2020 increased revenue requirements are offset by returning to customers a portion of the excess deferred income tax credits from Federal Tax Reform. Excess deferred income taxes and production tax credits are recognized based on an estimated annual effective tax rate, which contributed to a positive earnings variance in the first half of 2020. This positive earnings variance is expected to reverse in the second half of 2020.

LIQUIDITY AND CAPITAL RESOURCES

The liquidity and capital resources summary included in the 2019 Form 10-K has not changed materially, except as described below.

COVID-19 Considerations - Refer to “2020 Highlights” for discussion of COVID-19 and the current and expected impacts on Alliant Energy’s, IPL’s and WPL’s liquidity and capital resources.

Liquidity Position - At June 30, 2020, Alliant Energy had $208 million of cash and cash equivalents, $815 million ($303 million at the parent company, $250 million at IPL and $262 million at WPL) of available capacity under the single revolving credit facility and $89 million of available capacity at IPL under its sales of accounts receivable program.

33

Capital Structure - Capital structures at June 30, 2020 were as follows (Long-term Debt (including current maturities) (LD); Short-term Debt (SD); Common Equity (CE); IPL’s Preferred Stock (PS)):

Cash Flows - Selected information from the cash flows statements was as follows (in millions):

	Alliant Energy						IPL						WPL
	2020			2019			2020			2019			2020			2019
Cash, cash equivalents and restricted cash, January 1		$17.7			$25.5			$9.3			$12.4			$4.4			$9.2
Cash flows from (used for):
Operating activities	319.7			276.9			77.2			89.0			256.3			208.2
Investing activities	(392.3		)	(607.0		)	(125.2		)	(354.5		)	(259.8		)	(218.0		)
Financing activities	264.3			478.8			242.2			259.5			2.3			165.1
Net increase (decrease)	191.7			148.7			194.2			(6.0		)	(1.2		)	155.3
Cash, cash equivalents and restricted cash, June 30		$209.4			$174.2			$203.5			$6.4			$3.2			$164.5

Operating Activities - The following items contributed to increased (decreased) operating activity cash flows for the six months ended June 30, 2020 compared to the same period in 2019 (in millions):

	Alliant Energy			IPL			WPL
Higher collections from IPL’s retail electric and gas base rate increases		$54			$54			$—
Lower purchased power capacity payments at WPL	15			—			15
Refunds received in 2020 related to the MISO transmission owner return on equity complaint November 2019 FERC order (Refer to Note 13(f))	13			10			3
Changes in levels of production fuel	6			(15		)	21
Amounts issued to IPL’s retail electric customers in 2020 through its transmission cost rider for amounts previously collected in rates (Refer to Note 2)	(42		)	(42		)	—
Decreased collections from IPL’s and WPL’s retail customers caused by temperature impacts on electric and gas sales	(11		)	(8		)	(3		)
Changes in income taxes paid/refunded	(8		)	(5		)	8
Changes in interest payments	(5		)	(13		)	2
Other (primarily due to other changes in working capital)	21			7			2
		$43			($12	)		$48

Investing Activities - The following items contributed to increased (decreased) investing activity cash flows for the six months ended June 30, 2020 compared to the same period in 2019 (in millions):

	Alliant Energy		IPL		WPL
Lower (higher) utility construction and acquisition expenditures (a)		$69		$140		($71	)
Changes in the amount of cash receipts on sold receivables	84		84		—
Refund from ATC in 2020 for construction deposits WPL previously provided to ATC for transmission network upgrades for the West Riverside Energy Center	46		—		46
Expenditures for new acquisitions at AEF in 2019	13		—		—
Other	3		5		(17		)
		$215		$229		($42	)

(a) Largely due to lower expenditures for IPL’s expansion of wind generation and WPL’s West Riverside Energy Center, partially offset by higher expenditures for IPL’s and WPL’s electric and gas distribution systems and WPL’s expansion of wind generation.

Construction and Acquisition Expenditures - Refer to “2020 Highlights” for discussion of WPL’s estimated portion of capital expenditures for its requested 675 MW of new solar generation, as well as amounts WPL would receive related to a portion of the construction costs that are projected to be financed by a tax equity partner.

34

Financing Activities - The following items contributed to increased (decreased) financing activity cash flows for the six months ended June 30, 2020 compared to the same period in 2019 (in millions):

	Alliant Energy			IPL			WPL
Higher payments to retire long-term debt		($650	)		($200	)		($150	)
Net changes in the amount of commercial paper outstanding	(101		)	50			(25		)
Higher net proceeds from issuance of long-term debt	400			100			—
Higher net proceeds from common stock issuances	174			—			—
Higher capital contributions from IPL’s and WPL’s parent company, Alliant Energy	—			75			25
Other (includes higher dividend payments in 2020)	(38		)	(42		)	(13		)
		($215	)		($17	)		($163	)

Common Stock Issuances - Refer to Note 5 for discussion of common stock issuances by Alliant Energy in 2020.

Long-term Debt - Refer to Note 6(b) for discussion of IPL’s, WPL’s and AEF’s issuances and retirements of long-term debt in 2020.

Off-Balance Sheet Arrangements and Certain Financial Commitments - A summary of Alliant Energy’s and IPL’s off-balance sheet arrangements and Alliant Energy’s, IPL’s and WPL’s contractual obligations is included in the 2019 Form 10-K and has not changed materially from the items reported in the 2019 Form 10-K, except for the items described in Notes 3, 6 and 13.

OTHER MATTERS

Critical Accounting Policies and Estimates - The summary of critical accounting policies and estimates included in the 2019 Form 10-K has not changed materially, except as described below.

Contingencies - Effective January 1, 2020 upon the adoption of the new accounting standard for credit losses, certain contingencies, such as Alliant Energy Resources, LLC’s guarantees of the partnership obligations of an affiliate of Whiting Petroleum, require estimation each reporting period of the expected credit losses on those contingencies. These estimates require significant judgment and would result in recognition of a credit loss liability sooner than the previous accounting standards, which required recognition when the contingency became probable and could be reasonably estimated based on then current available information. With respect to Alliant Energy’s guarantees of the partnership obligations of an affiliate of Whiting Petroleum, the most significant judgments in determining the credit loss liability were the estimate of the exposure under the guarantees and the methodology used for calculating the credit loss liability. As of June 30, 2020, Alliant Energy currently estimates the exposure to be the affiliate’s share of the known partnership abandonment obligations. The methodology used to determine the credit loss liability considers both quantitative and qualitative information, which utilizes potential outcomes in a range of possible estimated amounts. Factors considered include market and external data points, as well as the affiliate’s share of forecasted cash flow expenditures associated with the abandonment obligations based on information made available to Alliant Energy by Whiting Petroleum. Note 1(c) provides discussion of the adoption of the new accounting standard for credit losses. Note 13(c) provides further discussion of contingencies assessed at January 1, 2020 and June 30, 2020, including impacts to Alliant Energy Resources, LLC’s guarantees in the partnership obligations of an affiliate of Whiting Petroleum and to the other partners.

ITEM 3. QUANTITATIVE AND QUALITATIVE DISCLOSURES ABOUT MARKET RISK

Quantitative and Qualitative Disclosures About Market Risk are reported in the 2019 Form 10-K and have not changed materially.

ITEM 4. CONTROLS AND PROCEDURES

Alliant Energy’s, IPL’s and WPL’s management evaluated, with the participation of each of Alliant Energy’s, IPL’s and WPL’s Chief Executive Officer, Chief Financial Officer and Disclosure Committee, the effectiveness of the design and operation of Alliant Energy’s, IPL’s and WPL’s disclosure controls and procedures (as defined in Rule 13a-15(e) of the Securities Exchange Act of 1934) as of June 30, 2020 pursuant to the requirements of the Securities Exchange Act of 1934, as amended. Based on their evaluation, the Chief Executive Officer and the Chief Financial Officer concluded that Alliant Energy’s, IPL’s and WPL’s disclosure controls and procedures were effective as of the quarter ended June 30, 2020.

There was no change in Alliant Energy’s, IPL’s and WPL’s internal control over financial reporting that occurred during the quarter ended June 30, 2020 that has materially affected, or is reasonably likely to materially affect, Alliant Energy’s, IPL’s or WPL’s internal control over financial reporting. Alliant Energy, IPL and WPL have not experienced any material impact to their internal control over financial reporting due to the COVID-19 pandemic, and continue to monitor and assess the impact COVID-19 has on their internal controls.

35

PART II. OTHER INFORMATION

ITEM 1A. RISK FACTORS

The risk factors described in Item 1A in the 2019 Form 10-K have not changed materially, except as described below.

The recent outbreak of the novel coronavirus (COVID-19) pandemic could adversely affect our business functions, financial condition, results of operations and cash flows - The continued spread of the novel coronavirus (COVID-19) has resulted in widespread impacts on the economy and could lead to a prolonged reduction in economic activity, disruptions to supply chains and capital markets, and reduced labor availability and productivity. The COVID-19 pandemic has impacted and may continue to impact the economic conditions in our service territories, which may adversely impact our sales and our customers’ abilities to pay their bills. Travel and transportation restrictions and closures of commercial spaces and industrial facilities have been imposed in and across the U.S., including in the service territories in which we operate. Governmental and regulatory responses to COVID-19 include suspending service disconnects and waiving late fees, which may increase customer account arrears, possibly increasing our allowance for expected credit losses and decreasing our cash flows.

Although we expect an increase in residential sales due to these closures, our commercial and industrial sales may be significantly reduced. The negative impacts on the economy could adversely impact the market value of the assets that fund our pension plans, which could necessitate accelerated funding of the plans to meet minimum federal government requirements. The negative impacts on the economy could also adversely impact the ability of counterparties to meet contractual payment obligations, including guarantees, or deliver contracted commodities and other goods or services at the contracted price, which could increase company expenses. Our access to the capital markets could be adversely affected by COVID-19, which could cause us to need alternative sources of funding for our operations and for working capital, any of which could increase our cost of capital.

Travel bans and restrictions, quarantines, shelter in place orders and shutdowns may cause disruptions in supply chains or access to labor that may adversely impact our planned construction projects, our ability to satisfy compliance requirements, or our operations, including our ability to maintain reliable electric and gas service. This may cause us to miss milestones on construction projects and experience operational delays, which, in the case of renewable energy projects, could delay our completion of such projects past the in-service dates required to qualify for the maximum general production tax credits or investment tax credits for investments in such renewable energy projects. We have already modified certain business practices consistent with government restrictions and best practices encouraged by government and regulatory authorities and are developing and implementing risk mitigation plans for critical items and services required to continue our operations. The effects of these government restrictions could adversely impact implementation of our regulatory plans and our operations. If our workforce contracts COVID-19, it could negatively impact our operations, including our ability to maintain reliable electric and gas service.

The degree to which COVID-19 may impact our business operations, financial condition and results of operations is unknown at this time and will depend on future developments, including the ultimate geographic spread of COVID-19, the severity of the disease, the duration of the outbreak, possible resurgence of the disease at a later date, and further actions that may be taken by governmental and regulatory authorities.

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

A summary of Alliant Energy common stock repurchases for the quarter ended June 30, 2020 was as follows:

	Total Number	Average Price		Total Number of Shares	Maximum Number (or Approximate
	of Shares	Paid Per		Purchased as Part of	Dollar Value) of Shares That May
Period	Purchased (a)	Share		Publicly Announced Plan	Yet Be Purchased Under the Plan (a)
April 1 through April 30	3,690		$53.06	—	N/A
May 1 through May 31	3,120	46.00		—	N/A
June 1 through June 30	69	47.79		—	N/A
	6,879	49.80		—

(a) All shares were purchased on the open market and held in a rabbi trust under the Alliant Energy Deferred Compensation Plan. There is no limit on the number of shares of Alliant Energy common stock that may be held under the Deferred Compensation Plan, which currently does not have an expiration date.

36

ITEM 6. EXHIBITS

The following Exhibits are filed herewith or incorporated herein by reference.

Exhibit Number	Description
4.1	Officers’ Certificate, dated as of April 2, 2020, creating WPL’s 3.65% Debentures due April 1, 2050 (incorporated by reference to Exhibit 4.1 to WPL’s Form 8-K, filed April 2, 2020 (File No. 0-337))
4.2	Officer’s Certificate, dated as of June 2, 2020, creating IPL’s 2.3% Senior Debentures due June 1, 2030 (incorporated by reference to Exhibit 4.1 to IPL’s Form 8-K, filed June 2, 2020 (File No. 1-4117))
10.1#	Alliant Energy 2020 Omnibus Incentive Plan (incorporated by reference to Appendix A to Alliant Energy’s definitive proxy statement filed on Schedule 14A on April 9, 2020 (File No. 1-9894))
10.1a#	Form of Performance Share Agreement pursuant to the Alliant Energy 2020 Omnibus Incentive Plan
10.1b#	Form of Restricted Stock Unit Agreement pursuant to the Alliant Energy 2020 Omnibus Incentive Plan
10.1c#	Form of Performance Restricted Stock Unit Agreement pursuant to the Alliant Energy 2020 Omnibus Incentive Plan
31.1	Certification of the Chief Executive Officer for Alliant Energy
31.2	Certification of the Chief Financial Officer for Alliant Energy
31.3	Certification of the Chief Executive Officer for IPL
31.4	Certification of the Chief Financial Officer for IPL
31.5	Certification of the Chief Executive Officer for WPL
31.6	Certification of the Chief Financial Officer for WPL
32.1	Written Statement of the Chief Executive Officer and Chief Financial Officer Pursuant to 18 U.S.C.§1350 for Alliant Energy
32.2	Written Statement of the Chief Executive Officer and Chief Financial Officer Pursuant to 18 U.S.C.§1350 for IPL
32.3	Written Statement of the Chief Executive Officer and Chief Financial Officer Pursuant to 18 U.S.C.§1350 for WPL
101.INS	Inline XBRL Instance Document - the instance document does not appear in the Interactive Data File because its XBRL tags are embedded within the Inline XBRL document
101.SCH	Inline XBRL Taxonomy Extension Schema Document
101.CAL	Inline XBRL Taxonomy Extension Calculation Linkbase Document
101.LAB	Inline XBRL Taxonomy Extension Label Linkbase Document
101.PRE	Inline XBRL Taxonomy Extension Presentation Linkbase Document
101.DEF	Inline XBRL Taxonomy Extension Definition Linkbase Document
104	Cover Page Interactive Data File (embedded within the Inline XBRL document)

# A management contract or compensatory plan or arrangement.

SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934, Alliant Energy Corporation, Interstate Power and Light Company and Wisconsin Power and Light Company have each duly caused this report to be signed on its behalf by the undersigned thereunto duly authorized on the 7th day of August 2020.

ALLIANT ENERGY CORPORATION
Registrant
By: /s/ Benjamin M. Bilitz	Chief Accounting Officer and Controller
Benjamin M. Bilitz	(Principal Accounting Officer and Authorized Signatory)

INTERSTATE POWER AND LIGHT COMPANY
Registrant
By: /s/ Benjamin M. Bilitz	Chief Accounting Officer and Controller
Benjamin M. Bilitz	(Principal Accounting Officer and Authorized Signatory)

WISCONSIN POWER AND LIGHT COMPANY
Registrant
By: /s/ Benjamin M. Bilitz	Chief Accounting Officer and Controller
Benjamin M. Bilitz	(Principal Accounting Officer and Authorized Signatory)

37

EX-10.1A

Exhibit 10.1a

FORM OF ALLIANT ENERGY CORPORATION

PERFORMANCE SHARE AGREEMENT

THIS PERFORMANCE SHARE AGREEMENT (this “Agreement”) is made and entered into as of this ____ day of _________, 20__ (the “Grant Date”) by and between Alliant Energy Corporation, a Wisconsin corporation (the “Company”), and ###PARTICIPANT_NAME###, a key employee of the Company (the “Employee”).

R E C I T A L S

WHEREAS, the Company has in effect the Alliant Energy Corporation 2020 Omnibus Incentive Plan (the “Plan”), the terms of which, to the extent not stated herein, are specifically incorporated by reference in this Agreement and capitalized terms used herein which are not otherwise defined shall have the meaning set forth in the Plan;

WHEREAS, one of the purposes of the Plan is to permit the grant of various equity-based incentive awards, including performance shares (the “Performance Shares”), to individuals selected by the Compensation and Personnel Committee of the Board of Directors of the Company (the “Committee”);

WHEREAS, the Employee is now employed by the Company or an Affiliate of the Company in a key capacity and has exhibited judgment, initiative and efforts which have contributed materially to the successful performance of the Company and/or its Affiliates; and

WHEREAS, the Company desires the Employee to remain as an employee of the Company or its Affiliates and wishes to provide the Employee with the opportunity to secure or increase his or her stock ownership in the Company in order to develop even a stronger incentive to put forth maximum effort for the continued success and growth of the Company.

A G R E E M E N T

NOW, THEREFORE, in consideration of the premises and of the covenants and agreements herein set forth, the parties hereby mutually covenant and agree as follows:

1. Award. Subject to the terms of this Agreement and the Plan, the Employee is hereby granted ###TOTAL_AWARDS### target Performance Shares on the Grant Date. Performance Shares granted under this Agreement are units that will be reflected in a book account maintained by the Company during the Performance Period set forth below, and that will be settled in Shares to the extent provided in this Agreement and the Plan.

2. Performance Period; Performance Goals.

(a) The “Performance Period” is the period beginning on ###DATE### and ending on ###DATE###.

(b) Except as otherwise provided in this Agreement (including Section 9 below), the Performance Shares will become earned based on achievement of the requisite performance goal or performance goals (the “Performance Goals”) determined in accordance with the provisions of Exhibit 1, which is attached to and forms a part of this Agreement. Any unearned Performance Shares automatically will terminate and be cancelled, without the payment of any consideration following the last day of the Performance Period.

3. Settlement of Awards. Subject to Section 9 below, the Company shall deliver to the Employee one Share for each Performance Share earned by the Employee, as determined in accordance with the provisions of Exhibit 1, except that cash shall be distributed in lieu of any fractional Share.

2020 Omnibus Performance Shares 1

4. Time of Payment. Except as otherwise provided in this Agreement (including Section 9 below), payment of Performance Shares earned in accordance with the provisions of Section 3 will be delivered as soon as practicable (but in any event within 75 days) following the last day of the Performance Period set forth in Section 2(a), subject to the Committee approving in writing as to the satisfaction of the requisite Performance Goal or Goals.

5. Retirement, Disability, or Death During Performance Period and Prior to a Change in Control. If the Employee’s employment with the Company and its Affiliates terminates during the Performance Period and prior to a Change in Control because of the Employee’s Retirement (as defined below), Disability, or death, the Employee shall be entitled to the full value of the Award earned in accordance with Exhibit 1, determined at the end of the Performance Period, so long as the termination event occurs after the end of the first year of the Performance Period and only if and to the extent the Performance Goals are met. If the termination event occurs during the first year of the Performance Period, the Employee will be entitled to a prorated value of the Award, earned in accordance with Exhibit 1, determined at the end of the Performance Period and only if and to the extent the Performance Goals are met, based on a fraction, the numerator of which is the number of months the Employee was employed during the Performance Period and the denominator of which is 12.

6. Involuntary Termination Without Cause During Performance Period and Prior to a Change in Control. If the Employee’s employment with the Company and its Affiliates terminates during the Performance Period and prior to a Change in Control because of an Involuntary Termination without Cause (as defined below), the Employee shall be entitled to the prorated value of the Award earned, determined at the end of the Performance Period and only if and to the extent the Performance Goals are met, based on a fraction, the numerator of which is the number of months the Employee was employed during the Performance Period and the denominator of which is 36.

7. Other Terminations of Employment During Performance Period. If the Employee’s employment with the Company and its Affiliates terminates during the Performance Period and prior to a Change in Control for any reason other than the Employee’s Retirement, Disability, Involuntary Termination without Cause, or death, the Performance Shares granted under this Agreement automatically will terminate and be cancelled on the date of such termination of employment.

8. Dividend Equivalents.

(a) After the Performance Period has ended (or, if a Change in Control occurs during the Performance Period, the effective date of the Change in Control), dividend equivalents (“Dividend Equivalents”) will be calculated and credited to the account of the Employee with respect to the percentage of Performance Shares that are earned (as determined in accordance with Section 3 or Section 9(a)(i) as applicable). Dividend Equivalents will be credited as additional Performance Shares, the number of which will be equal to the number of whole Shares that could be purchased with the amount of the Dividend Equivalents, based on the Fair Market Value of the Shares as of the dividend payment date and the number of earned Performance Shares (as determined in accordance with Section 3 or Section 9(a)(i) as applicable).

(b) Any Dividend Equivalents credited to the Employee’s account pursuant to this Section 8 shall not be vested or paid until the dates of vesting or payment of the Performance Shares with respect to which such Dividend Equivalents are credited, and such Dividend Equivalents shall be subject to the same restrictions and other terms and conditions as apply to the Performance Shares with respect to which they were credited.

(c) No Dividend Equivalents shall be credited to the Employee with respect to record dates occurring prior to the Grant Date or with respect to record dates occurring on or after the date, if any, on which the Performance Shares are cancelled and terminated.

9. Change in Control.

(a) No Termination of Employment Prior to a Change in Control.

2020 Omnibus Performance Shares 2

(i) Notwithstanding anything to the contrary in the Plan, this Agreement, or the Employee’s employment agreement or any other agreement to which the Employee is a party, if a Change in Control occurs during the Performance Period and the Employee’s employment does not terminate before the effectiveness of the Change in Control, then the Employee shall be entitled to the earned Performance Shares (as determined in accordance with this Section 9(a)(i)), which automatically will convert into a contractual right to receive a cash payment (the “Cash Payment Right”) in an amount equal to (i) the number of earned Performance Shares (including any additional Performance Shares determined in accordance with Section 8(a)), multiplied by (ii) the per Share Fair Market Value as of the trading day immediately preceding the effective date of the Change in Control. For purposes of this Section 9, the “earned Performance Shares” means the number of Performance Shares that would have been earned by the Employee in accordance with Exhibit 1 assuming that the day immediately preceding the effective date of the Change in Control is the last day of the Performance Period. After such conversion, no interest or Dividend Equivalents will be accrued, credited or paid with respect to the Cash Payment Right. Any portion of the Performance Shares that is not converted into the Cash Payment Right automatically shall terminate and be cancelled immediately prior to the effectiveness of the Change in Control, without the payment of any consideration therefor.

(ii) Notwithstanding anything to the contrary in the Plan, this Agreement, or the Employee’s employment agreement or any other agreement to which the Employee is a party, the Cash Payment Right shall be paid as soon as practicable (but in any event within 75 days) after the last day of the Performance Period set forth in Section 2(a), provided that the Employee remains continuously employed by the Company or an Affiliate or any successor thereto through the last day of such Performance Period. Notwithstanding the immediately preceding sentence, in the event that the Employee experiences a termination of employment due to the Employee’s Retirement (as defined below), Disability, or death or an involuntary termination of employment by action of the Company(or its successor)(other than a termination due to Cause) or due to the Employee’s resignation for Good Reason prior to the last day of the Performance Period set forth in Section 2(a), the Cash Payment Right will be paid in accordance with the first sentence of this Section 9(a)(ii) as though the Employee remained continuously employed by the Company or an Affiliate or any successor thereto through the last day of the Performance Period.

(b) Certain Terminations of Employment Prior to a Change in Control. Solely for purposes of Sections 5 and 6 of the Agreement, if the Employee’s employment terminates for any of the reasons set forth in such Sections 5 and 6 prior to a Change in Control and a Change in Control occurs during the Performance Period, then the Employee shall be entitled to the earned Performance Shares determined in accordance with Section 9(a)(i) in lieu of any amount set forth in Section 5 or Section 6, as applicable, which Performance Shares automatically shall convert into a contractual right to receive the Cash Payment Right. After such conversion, no interest or Dividend Equivalents will be accrued, credited or paid with respect to the Cash Payment Right. For the avoidance of doubt, the Cash Payment Right will be paid at such time provided under Section 4.

10. Definitions.

(a) “Involuntary Termination without Cause” shall mean that the Employee experiences a termination of employment due to the Employee’s (i) receipt of a written notification that his or her position is being eliminated as a result of a structured job elimination program or (ii) resignation for a Pre-Change in Control Good Reason.

(b) “Pre-Change in Control Good Reason” shall mean that an applicable event occurs and the Employee provides notice to the Company of the existence of the event within 90 days of the initial existence of the event, the Company fails to cure the event within 30 days of such notice and the Employee resigns within 30 days following the last day of such 30-day cure period. The applicable events are any one or more of the following: (i) a material diminution in the Employee’s base compensation and (ii) a material diminution in the Employee’s authority, duties, or responsibilities.

(c) “Retirement” shall mean the Employee’s employment terminates (with the consent of the Company) after he or she has reached age 55 and the Employee’s age, in whole years, added to

2020 Omnibus Performance Shares 3

the number of whole years of the Employee’s continuous employment with the Company total 65 or more.

11. Nontransferability of Performance Shares. The Performance Shares shall not be assignable, alienable, saleable or transferable by the Employee other than by will or the laws of descent and distribution prior to settlement of the Awards pursuant to Section 3 (or, if applicable, Section 9); provided, however, that the Employee shall be entitled, in the manner provided in Section 13 hereof, to designate a beneficiary to receive any Shares or cash issuable with respect to the Award upon the death of the Employee.

12. Tax Withholding. The Company may deduct and withhold from any cash otherwise payable to the Employee such amount as may be required for the purpose of satisfying the Company’s obligation to withhold federal, state or local taxes. Further, in the event the amount so withheld is insufficient for such purpose, the Company may require that the Employee pay to the Company upon its demand or otherwise make arrangements satisfactory to the Company for payment of, such amount as may be requested by the Company in order to satisfy its obligation to withhold any such taxes.

The Employee shall be permitted to satisfy the Company’s tax withholding requirements by making a written election (in accordance with such rules and regulations and in such form as the Committee may determine) to have the Company withhold Shares otherwise issuable to the Employee (the “Withholding Election”) having a Fair Market Value on the date income is recognized (the “Tax Date”) pursuant to the settlement of the Award equal to the minimum amount required to be withheld (or such other applicable rate permitted by the Company that avoids adverse treatment for financial accounting purposes). If the number of Shares withheld to satisfy withholding tax requirements shall include a fractional Share, the number of Shares withheld shall be reduced to the next lower whole number and the Employee shall deliver cash in lieu of such fractional Share, or otherwise make arrangements satisfactory to the Company for payment of such amount. A Withholding Election must be received by the Corporate Secretary of the Company on or prior to the Tax Date.

13. Designation of Beneficiary. The Employee shall be permitted to designate one or more beneficiaries (each, a “Beneficiary”) on a Company-approved form who shall be entitled to payouts hereunder, to the extent payouts are made, after the death of the Employee. The terms and conditions of any such designation (including any changes thereto by the Employee) shall be subject to the terms and conditions of such Company-approved beneficiary designation form. If no such beneficiary designation is in effect at the time of the Employee’s death, or if no designated Beneficiary survives the Employee or if such designation conflicts with law, the Employee’s estate acting through his or her legal representative shall be entitled to receive payouts hereunder, to the extent they are made, after the death of the Employee. If the Committee is in doubt as to the right of any person to the Performance Shares or any payout thereunder, the Company may refuse to settle such matter, without liability for any interest or dividends on the Performance Shares, until the Committee determines the person entitled to the Performance Shares or any payout thereunder, or the Company may apply to any court of appropriate jurisdiction and such application shall be a complete discharge of the liability of the Company therefor.

14. Transfer Restriction. Any Shares delivered pursuant to Section 3 hereof shall thereafter be freely transferable by the Employee, provided that the Employee agrees for himself or herself and his or her heirs, legatees and legal representatives, with respect to all Shares acquired pursuant to the terms and conditions of this Agreement (or any Shares issued pursuant to a stock dividend or stock split thereon or any securities issued in lieu thereof or in substitution or exchange therefor), that he or she and his or her heirs, legatees and legal representatives will not sell or otherwise dispose of such shares except pursuant to a registration statement filed by the Company with the Securities and Exchange Commission under the Securities Act of 1933, as amended (the “Act”), or except in a transaction which is determined by counsel to the Company to be exempt from registration under the Act and any applicable state securities laws; and to execute and deliver to the Company such investment representations and warranties, and to take such other actions, as counsel for the Company determines may be necessary or appropriate for compliance with the Act and any other applicable securities laws. The Employee agrees that any certificates representing any of the Shares acquired pursuant to the terms and conditions of this Agreement may bear such legend or legends as the Company deems appropriate in order to assure compliance with applicable securities laws.

15. Status of Employee. The Employee shall not be deemed for any purposes to be a shareowner of the Company with respect to any of the Performance Shares except to the extent that the Company has

2020 Omnibus Performance Shares 4

delivered Shares pursuant to Section 3 hereof. Therefore, the Employee will not have the right of shareowners to vote or, subject to Section 8, to receive dividends or distributions of any kind prior to the Company delivering Shares pursuant to Section 3 hereof. Neither the Plan nor the Performance Shares shall confer upon the Employee any right to continue as an employee of the Company or any of its Affiliates, nor to interfere in any way with the right of the Company to terminate the employment or directorship of the Employee at any time.

16. Powers of the Company Not Affected. The existence of the Performance Shares shall not affect in any way the right or power of the Company or its shareowners to make or authorize any or all adjustments, recapitalizations, reorganizations or other changes in the Company’s capital structure or its business, or any merger or consolidation of the Company, or any issuance of bonds, debentures, preferred or prior preference stock senior to or affecting the Shares or the rights thereof, or dissolution or liquidation of the Company, or any sale or transfer of all or any part of the Company’s assets or business or any other corporate act or proceeding, whether of a similar character or otherwise.

17. Interpretation by the Committee. As a condition of the granting of the Performance Shares, the Employee agrees, for himself or herself and for his or her legal representatives or guardians, that this Agreement shall be interpreted by the Committee and that any interpretation by the Committee of the terms of this Agreement and any determination made by the Committee pursuant to this Agreement shall be final, binding and conclusive.

18. Miscellaneous.

(a) This Agreement shall be governed and construed in accordance with the internal laws of the State of Wisconsin applicable to contracts made and to be performed therein between residents thereof. As a condition of the granting of the Performance Shares, the Employee irrevocably consents to the nonexclusive jurisdiction and venue of the state and federal courts located in the State of Wisconsin.

(b) The Plan and this Agreement set forth the entire understanding between the Company and the Employee with respect to the subject matter hereof and shall supersede in all respects, and the Employee hereby waives all rights under, any prior or other agreement or understanding between the parties with respect to such subject matter, including, but not limited to, any Key Executive Employment and Severance Agreement. For the avoidance of doubt, the Plan and this Agreement shall control in the event there is any express conflict between the Plan and this Agreement and any prior or other agreement or understanding between the parties.

(c) This Agreement may not be amended or modified except by the written consent of the parties hereto. Notwithstanding the foregoing, the Committee need not obtain Employee (or other interested party) consent for any such action: (i) to the extent the action is deemed necessary by the Committee to comply with any applicable law; (ii) to the extent the action is deemed necessary by the Committee to preserve favorable accounting or tax treatment for the Company of any Award; (iii) to the extent the Committee determines that such action does not materially and adversely affect the value of an Award or that such action is in the best interest of the affected Employee; or (iv) to the extent unilateral action by the Committee is permitted under Section 14(c) of the Plan.

(d) The Award and any Shares or cash issued thereunder shall be subject to potential cancellation, rescission, payback, recoupment or other action in accordance with the terms of any Company clawback policy (the “Clawback Policy”), as then in effect and as it may be amended from time to time, to the extent the Clawback Policy applies to the Award and any Shares or cash issued thereunder (including a Clawback Policy implemented or amendments made thereto after the Grant Date for the Award). By accepting the Performance Shares, the Employee agrees to execute any additional documents as may be requested by the Company to effect the Company’s application, implementation and adoption of a Clawback Policy with respect to the Award and any Shares or cash issued thereunder.

(e) The captions of this Agreement are inserted for convenience of reference only and shall not be taken into account in construing this Agreement.

2020 Omnibus Performance Shares 5

IN WITNESS WHEREOF, the Company has caused this Agreement to be executed by its duly authorized officer and the Employee has hereunto affixed his or her hand as of the day and year first above written.

ALLIANT ENERGY CORPORATION
(the “Company”)
By:
Its:
EMPLOYEE:
Employee's Signature
	###PARTICIPANT_NAME###
Employee's Printed Name

2020 Omnibus Performance Shares 6

EXHIBIT 1

PERFORMANCE SHARE GRANT – PERFORMANCE GOALS

1. Purpose: The purpose of this Exhibit 1 is to set forth the Performance Goal or Goals that will be applied to determine the amount of the Award that will be earned under the terms of the attached Performance Share Agreement (the “Agreement”). This Exhibit 1 is incorporated into and forms a part of the Agreement.

PARTICIPANT_NAME	20__
Grant Date	###GRANT_DATE###
Grant Date Fair Market Value	###MARKET_PRICE_AT_TIME_OF_GRANT###
Performance Shares (Target)	###TOTAL_AWARDS###
Performance Period	###DATE### through ###DATE###

2. Performance Goals: The Award will be based on the Company’s Total Shareholder Return (TSR) performance (which represents stock price appreciation plus dividends reinvested) based on the three-year average relative to an investor-owned utility peer group. The peer group is defined as the group that comprises the Edison Electric Institute (EEI) Stock Index.

3. Amount of Award: Actual awards will be based on Company performance as specified above and can range from ___ to ___ percent of target. The number of Performance Shares earned by the Employee shall be determined in accordance with the following schedule:

3-yr Total Shareholder Return – Percentile Relative to Peer Group*	% of Target Value Paid Out
__ percentile or greater	___%
__Percentile	___%
__Percentile	___%
__ Percentile	___%
__ Percentile	___%
__ Percentile	___%
__ Percentile	___%
Below __Percentile	___%

* Peer Group consists of companies comprising the Edison Electric Institute (EEI) Stock Index.

** Awards will be prorated for achievement of performance between the performance targets: If the TSR percentile relative to the Peer Group is between any two data points, the corresponding percentage of Performance Shares earned shall be determined by interpolation between the corresponding data points.

2020 Omnibus Performance Shares 7

EX-10.1B

Exhibit 10.1b

FORM OF ALLIANT ENERGY CORPORATION

RESTRICTED STOCK UNIT AGREEMENT

THIS RESTRICTED STOCK UNIT AGREEMENT (this “Agreement”) is made and entered into as of this ____ day of _________ 20__ (the “Grant Date”) by and between Alliant Energy Corporation, a Wisconsin corporation (the “Company”), and ###PARTICIPANT_NAME###, a key employee of the Company (the “Employee”).

R E C I T A L S

WHEREAS, the Company has in effect the Alliant Energy Corporation 2020 Omnibus Incentive Plan (the “Plan”), the terms of which, to the extent not stated herein, are specifically incorporated by reference in this Agreement and capitalized terms used herein which are not otherwise defined shall have the meaning set forth in the Plan;

WHEREAS, one of the purposes of the Plan is to permit the grant of various equity-based incentive awards, including time-vesting restricted stock units (“RSUs”), to individuals selected by the Compensation and Personnel Committee of the Board of Directors of the Company (the “Committee”);

WHEREAS, the Employee is now employed by the Company or an Affiliate of the Company in a key capacity and has exhibited judgment, initiative and efforts which have contributed materially to the successful performance of the Company and/or its Affiliates; and

WHEREAS, the Company desires the Employee to remain as an employee of the Company or its Affiliates and wishes to provide the Employee with the opportunity to secure or increase his or her stock ownership in the Company in order to develop even a stronger incentive to put forth maximum effort for the continued success and growth of the Company.

A G R E E M E N T

NOW, THEREFORE, in consideration of the premises and of the covenants and agreements herein set forth, the parties hereby mutually covenant and agree as follows:

1. Award. Subject to the terms of this Agreement and the Plan, the Employee is hereby granted ###TOTAL_AWARDS### RSUs on the Grant Date with a vesting commencement date of _________, 20__ (the “Vesting Commencement Date”). RSUs granted under this Agreement are units that will be reflected in a book account maintained by the Company during the Term set forth below, and that will be settled in Shares to the extent provided in this Agreement and the Plan.

2. Term; Vesting Schedule.

(a) The “Term” is the period beginning on the Vesting Commencement Date and ending on __________, 20__.

(b) Except as otherwise provided in this Agreement (including Section 9 below), each RSU will become earned and vested (each a “Vested RSU” and, collectively, “Vested RSUs”) on the last day of the Term set forth in Section 2(a), if the Employee is continuously employed with the Company or any of its Affiliates through the last day of the Term.

3. Settlement of Awards. Subject to Section 9 below, the Company shall deliver to the Employee one Share for each Vested RSU, except that cash shall be distributed in lieu of any fractional Share.

2020 Omnibus Restricted Stock Unit 1

4. Time of Payment. Except as otherwise provided in this Agreement (including Section 9 below), payment of Vested RSUs will be delivered as soon as practicable (but in any event within 75 days) following the last day of the Term set forth in Section 2(a).

5. Retirement, Disability, or Death During the Term and Prior to a Change in Control. If the Employee’s employment with the Company and its Affiliates terminates during the Term and prior to a Change in Control because of the Employee’s Retirement (as defined below), Disability, or death, the full number of RSUs shall be treated as Vested RSUs, so long as the termination event occurs on or after the first anniversary of the Vesting Commencement Date. If the employment termination event occurs prior to the first anniversary of the Vesting Commencement Date, a pro-rated number of RSUs shall be treated as Vested RSUs, based on a fraction, the numerator of which is the number of months the Employee was employed during the Term and the denominator of which is 12. Any RSUs that do not become Vested RSUs automatically will terminate and be cancelled, without the payment of any consideration, on the date the Employee’s employment with the Company and its Affiliates terminates.

6. Involuntary Termination Without Cause During the Term and Prior to a Change in Control. If the Employee’s employment with the Company and its Affiliates terminates after the first anniversary of the Vesting Commencement Date and prior to a Change in Control because of an Involuntary Termination without Cause (as defined below), a pro-rated number of RSUs shall be treated as Vested RSUs, based on a fraction, the numerator of which is the number of months the Employee was employed following the Vesting Commencement Date and the denominator of which is 36. Any RSUs that do not become Vested RSUs automatically will terminate and be cancelled, without the payment of any consideration, on the date the Employee’s employment with the Company and its Affiliates terminates.

7. Other Terminations of Employment During Term and Prior to Change in Control. If the Employee’s employment with the Company and its Affiliates terminates during the Term and prior to a Change in Control for any reason other than the Employee’s Retirement, Disability, Involuntary Termination without Cause, or death, the RSUs granted under this Agreement automatically will terminate and be cancelled on the date of such termination of employment without the payment of any consideration.

8. Dividend Equivalents.

(a) After the Term has ended (or, if a Change in Control occurs prior to the end of the Term, the effective date of the Change in Control), dividend equivalents (“Dividend Equivalents”) will be calculated and credited to the account of the Employee with respect to the number of Vested RSUs. Dividend Equivalents will be credited as additional RSUs, the number of which will be equal to the number of whole Shares that could be purchased with the amount of the Dividend Equivalents, based on the Fair Market Value of the Shares as of the dividend payment date and the number of Vested RSUs.

(b) Any Dividend Equivalents credited to the Employee’s account pursuant to this Section 8 shall not be vested or paid until the dates of vesting or payment of the RSUs with respect to which such Dividend Equivalents are credited, and such Dividend Equivalents shall be subject to the same restrictions and other terms and conditions as apply to the RSUs with respect to which they were credited.

(c) No Dividend Equivalents shall be credited to the Employee with respect to record dates occurring prior to the Grant Date or with respect to record dates occurring on or after the date, if any, on which the RSUs are cancelled and terminated.

9. Change in Control.

(a) Notwithstanding anything to the contrary in the Plan, this Agreement, or the Employee’s employment agreement or any other agreement to which the Employee is a party, if a Change in Control occurs during the Term and the Employee’s employment does not terminate before the effectiveness of the Change in Control, then the RSUs automatically will vest and convert into a contractual right to receive a cash payment (the “Cash Payment Right”) in an amount equal to (i) the full number of RSUs (including any additional RSUs determined in accordance with Section 8(a)), multiplied by (ii) the per Share Fair Market Value as of the trading day immediately preceding

2020 Omnibus Restricted Stock Unit 2

the effective date of the Change in Control. After such conversion, no interest or Dividend Equivalents will be accrued, credited or paid with respect to the Cash Payment Right.

(b) Notwithstanding anything to the contrary in the Plan, this Agreement, or the Employee’s employment agreement or any other agreement to which the Employee is a party, the Cash Payment Right shall be paid as soon as practicable (but in any event within 75 days) after the last day of the Term set forth in Section 2(a), provided that the Employee remains continuously employed by the Company or an Affiliate or any successor thereto through the last day of the Term. Notwithstanding the immediately preceding sentence, in the event that the Employee experiences a termination of employment due to the Employee’s Retirement (as defined below), Disability, or death or an involuntary termination of employment by action of the Company (or its successor) (other than a termination due to Cause) or due to the Employee’s resignation for Good Reason prior to the last day of the Term set forth in Section 2(a), the Cash Payment Right will be paid in accordance with the first sentence of this Section 9(b) as though the Employee remained continuously employed by the Company or an Affiliate or any successor thereto through the last day of the Term.

10. Definitions.

(a) “Involuntary Termination without Cause” shall mean that the Employee experiences a termination of employment due to the Employee’s (i) receipt of a written notification that his or her position is being eliminated as a result of a structured job elimination program or (ii) resignation for a Pre-Change in Control Good Reason.

(b) “Pre-Change in Control Good Reason” shall mean that an applicable event occurs and the Employee provides notice to the Company of the existence of the event within 90 days of the initial existence of the event, the Company fails to cure the event within 30 days of such notice and the Employee resigns within 30 days following the last day of such 30-day cure period. The applicable events are any one or more of the following: (i) a material diminution in the Employee’s base compensation and (ii) a material diminution in the Employee’s authority, duties, or responsibilities.

(c) “Retirement” shall mean the Employee’s employment terminates (with the consent of the Company) after he or she has reached age 55 and the Employee’s age, in whole years, added to the number of whole years of the Employee’s continuous employment with the Company total 65 or more.

11. Nontransferability of RSUs. The RSUs shall not be assignable, alienable, saleable or transferable by the Employee other than by will or the laws of descent and distribution prior to settlement of the Awards pursuant to Section 3 (or, if applicable, Section 9); provided, however, that the Employee shall be entitled, in the manner provided in Section 13 hereof, to designate a beneficiary to receive any Shares or cash issuable with respect to the Award upon the death of the Employee.

12. Tax Withholding. The Company may deduct and withhold from any cash otherwise payable to the Employee such amount as may be required for the purpose of satisfying the Company’s obligation to withhold federal, state or local taxes. Further, in the event the amount so withheld is insufficient for such purpose, the Company may require that the Employee pay to the Company upon its demand or otherwise make arrangements satisfactory to the Company for payment of, such amount as may be requested by the Company in order to satisfy its obligation to withhold any such taxes.

The Employee shall be permitted to satisfy the Company’s tax withholding requirements by making a written election (in accordance with such rules and regulations and in such form as the Committee may determine) to have the Company withhold Shares otherwise issuable to the Employee (the “Withholding Election”) having a Fair Market Value on the date income is recognized (the “Tax Date”) pursuant to the settlement of the Award equal to the minimum amount required to be withheld (or such other applicable rate permitted by the Company that avoids adverse treatment for financial accounting purposes). If the number of Shares withheld to satisfy withholding tax requirements shall include a fractional Share, the number of Shares withheld shall be reduced to the next lower whole number and the Employee shall deliver cash in lieu of such fractional Share, or otherwise make arrangements satisfactory to the Company for payment of such

2020 Omnibus Restricted Stock Unit 3

amount. A Withholding Election must be received by the Corporate Secretary of the Company on or prior to the Tax Date.

13. Designation of Beneficiary. The Employee shall be permitted to designate one or more beneficiaries (each, a “Beneficiary”) on a Company-approved form who shall be entitled to payouts hereunder, to the extent payouts are made, after the death of the Employee. The terms and conditions of any such designation (including any changes thereto by the Employee) shall be subject to the terms and conditions of such Company-approved beneficiary designation form. If no such beneficiary designation is in effect at the time of the Employee’s death, or if no designated Beneficiary survives the Employee or if such designation conflicts with law, the Employee’s estate acting through his or her legal representative shall be entitled to receive payouts hereunder, to the extent they are made, after the death of the Employee. If the Committee is in doubt as to the right of any person to the RSUs or any payout thereunder, the Company may refuse to settle such matter, without liability for any interest or dividends on the RSUs, until the Committee determines the person entitled to the RSUs or any payout thereunder, or the Company may apply to any court of appropriate jurisdiction and such application shall be a complete discharge of the liability of the Company therefor.

14. Transfer Restriction. Any Shares delivered pursuant to Section 3 hereof shall thereafter be freely transferable by the Employee, provided that the Employee agrees for himself or herself and his or her heirs, legatees and legal representatives, with respect to all Shares acquired pursuant to the terms and conditions of this Agreement (or any Shares issued pursuant to a stock dividend or stock split thereon or any securities issued in lieu thereof or in substitution or exchange therefor), that he or she and his or her heirs, legatees and legal representatives will not sell or otherwise dispose of such shares except pursuant to a registration statement filed by the Company with the Securities and Exchange Commission under the Securities Act of 1933, as amended (the “Act”), or except in a transaction which is determined by counsel to the Company to be exempt from registration under the Act and any applicable state securities laws; and to execute and deliver to the Company such investment representations and warranties, and to take such other actions, as counsel for the Company determines may be necessary or appropriate for compliance with the Act and any other applicable securities laws. The Employee agrees that any certificates representing any of the Shares acquired pursuant to the terms and conditions of this Agreement may bear such legend or legends as the Company deems appropriate in order to assure compliance with applicable securities laws.

15. Status of Employee. The Employee shall not be deemed for any purposes to be a shareowner of the Company with respect to any of the RSUs except to the extent that the Company has delivered Shares pursuant to Section 3 hereof. Therefore, the Employee will not have the right of shareowners to vote or, subject to Section 8, to receive dividends or distributions of any kind prior to the Company delivering Shares pursuant to Section 3 hereof. Neither the Plan nor the RSUs shall confer upon the Employee any right to continue as an employee of the Company or any of its Affiliates, nor to interfere in any way with the right of the Company to terminate the employment or directorship of the Employee at any time.

16. Powers of the Company Not Affected. The existence of the RSUs shall not affect in any way the right or power of the Company or its shareowners to make or authorize any or all adjustments, recapitalizations, reorganizations or other changes in the Company’s capital structure or its business, or any merger or consolidation of the Company, or any issuance of bonds, debentures, preferred or prior preference stock senior to or affecting the Shares or the rights thereof, or dissolution or liquidation of the Company, or any sale or transfer of all or any part of the Company’s assets or business or any other corporate act or proceeding, whether of a similar character or otherwise.

17. Interpretation by the Committee. As a condition of the granting of the RSUs, the Employee agrees, for himself or herself and for his or her legal representatives or guardians, that this Agreement shall be interpreted by the Committee and that any interpretation by the Committee of the terms of this Agreement and any determination made by the Committee pursuant to this Agreement shall be final, binding and conclusive.

18. Miscellaneous.

(a) This Agreement shall be governed and construed in accordance with the internal laws of the State of Wisconsin applicable to contracts made and to be performed therein between residents thereof.

2020 Omnibus Restricted Stock Unit 4

As a condition of the granting of the RSUs, the Employee irrevocably consents to the nonexclusive jurisdiction and venue of the state and federal courts located in the State of Wisconsin.

(b) The Plan and this Agreement set forth the entire understanding between the Company and the Employee with respect to the subject matter hereof and shall supersede in all respects, and the Employee hereby waives all rights under, any prior or other agreement or understanding between the parties with respect to such subject matter, including, but not limited to, any Key Executive Employment and Severance Agreement. For the avoidance of doubt, the Plan and this Agreement shall control in the event there is any express conflict between the Plan and this Agreement and any prior or other agreement or understanding between the parties.

(c) This Agreement may not be amended or modified except by the written consent of the parties hereto. Notwithstanding the foregoing, the Committee need not obtain Employee (or other interested party) consent for any such action: (i) to the extent the action is deemed necessary by the Committee to comply with any applicable law; (ii) to the extent the action is deemed necessary by the Committee to preserve favorable accounting or tax treatment for the Company of any Award; (iii) to the extent the Committee determines that such action does not materially and adversely affect the value of an Award or that such action is in the best interest of the affected Employee; or (iv) to the extent unilateral action by the Committee is permitted under Section 14(c) of the Plan.

(d) The Award and any Shares or cash issued thereunder shall be subject to potential cancellation, rescission, payback, recoupment or other action in accordance with the terms of any Company clawback policy (the “Clawback Policy”), as then in effect and as it may be amended from time to time, to the extent the Clawback Policy applies to the Award and any Shares or cash issued thereunder (including a Clawback Policy implemented or amendments made thereto after the Grant Date for the Award). By accepting the Award, the Employee agrees to execute any additional documents as may be requested by the Company to effect the Company’s application, implementation and adoption of a Clawback Policy with respect to the Award and any Shares or cash issued thereunder.

(e) The captions of this Agreement are inserted for convenience of reference only and shall not be taken into account in construing this Agreement.

IN WITNESS WHEREOF, the Company has caused this Agreement to be executed by its duly authorized officer and the Employee has hereunto affixed his or her hand as of the day and year first above written.

ALLIANT ENERGY CORPORATION
(the “Company”)
By:
Its:
EMPLOYEE:
Employee's Signature
	###PARTICIPANT_NAME###
Employee's Printed Name

2020 Omnibus Restricted Stock Unit 5

EX-10.1C

Exhibit 10.1c

FORM OF ALLIANT ENERGY CORPORATION

PERFORMANCE RESTRICTED STOCK UNIT AGREEMENT

THIS PERFORMANCE RESTRICTED STOCK UNIT AGREEMENT (this “Agreement”) is made and entered into as of this ____ day of ________ 20__ (the “Grant Date”) by and between Alliant Energy Corporation, a Wisconsin corporation (the “Company”), and ###PARTICIPANT_NAME###, a key employee of the Company (the “Employee”).

R E C I T A L S

WHEREAS, the Company has in effect the Alliant Energy Corporation 2020 Omnibus Incentive Plan (the “Plan”), the terms of which, to the extent not stated herein, are specifically incorporated by reference in this Agreement and capitalized terms used herein which are not otherwise defined shall have the meaning set forth in the Plan;

WHEREAS, one of the purposes of the Plan is to permit the grant of various equity-based incentive awards, including performance restricted stock units (“PRSUs”), to individuals selected by the Compensation and Personnel Committee of the Board of Directors of the Company (the “Committee”);

WHEREAS, the Employee is now employed by the Company or an Affiliate of the Company in a key capacity and has exhibited judgment, initiative and efforts which have contributed materially to the successful performance of the Company and/or its Affiliates; and

WHEREAS, the Company desires the Employee to remain as an employee of the Company or its Affiliates and wishes to provide the Employee with the opportunity to secure or increase his or her stock ownership in the Company in order to develop even a stronger incentive to put forth maximum effort for the continued success and growth of the Company.

A G R E E M E N T

NOW, THEREFORE, in consideration of the premises and of the covenants and agreements herein set forth, the parties hereby mutually covenant and agree as follows:

1. Award. Subject to the terms of this Agreement and the Plan, the Employee is hereby granted ###TOTAL_AWARDS### target PRSUs on the Grant Date. PRSUs granted under this Agreement are units that will be reflected in a book account maintained by the Company during the Performance Period set forth below, and that will be settled in Shares to the extent provided in this Agreement and the Plan.

2. Performance Period; Performance Goals.

(a) The “Performance Period” is the period beginning on ###DATE### and ending on ###DATE###.

(b) Except as otherwise provided in this Agreement (including Section 9 below), the PRSUs will become earned based on achievement of the requisite performance goal or performance goals (the “Performance Goals”) determined in accordance with the provisions of Exhibit 1, which is attached to and forms a part of this Agreement. Any unearned PRSUs automatically will terminate and be cancelled, without the payment of any consideration following the last day of the Performance Period.

3. Settlement of Awards. Subject to Section 9 below, the Company shall deliver to the Employee one Share for each PRSU earned by the Employee, as determined in accordance with the provisions of Exhibit 1, except that cash shall be distributed in lieu of any fractional Share.

2020 Omnibus Performance Restricted Stock Unit 1

4. Time of Payment. Except as otherwise provided in this Agreement (including Section 9 below), payment of PRSUs earned in accordance with the provisions of Section 3 will be delivered as soon as practicable (but in any event within 75 days) following the last day of the Performance Period set forth in Section 2(a), subject to the Committee approving in writing as to the satisfaction of the requisite Performance Goal or Goals.

5. Retirement, Disability, or Death During Performance Period and Prior to a Change in Control. If the Employee’s employment with the Company and its Affiliates terminates during the Performance Period and prior to a Change in Control because of the Employee’s Retirement (as defined below), Disability, or death, the Employee shall be entitled to the full value of the Award earned in accordance with Exhibit 1, determined at the end of the Performance Period, so long as the termination event occurs after the end of the first year of the Performance Period and only if and to the extent the Performance Goals are met. If the termination event occurs during the first year of the Performance Period, the Employee will be entitled to a prorated value of the Award, earned in accordance with Exhibit 1, determined at the end of the Performance Period and only if and to the extent the Performance Goals are met, based on a fraction, the numerator of which is the number of months the Employee was employed during the Performance Period and the denominator of which is 12.

6. Involuntary Termination Without Cause During Performance Period and Prior to a Change in Control. If the Employee’s employment with the Company and its Affiliates terminates during the Performance Period and prior to a Change in Control because of an Involuntary Termination without Cause (as defined below), the Employee shall be entitled to the prorated value of the Award earned, determined at the end of the Performance Period and only if and to the extent the Performance Goals are met, based on a fraction, the numerator of which is the number of months the Employee was employed during the Performance Period and the denominator of which is 36.

7. Other Terminations of Employment During Performance Period. If the Employee’s employment with the Company and its Affiliates terminates during the Performance Period and prior to a Change in Control for any reason other than the Employee’s Retirement, Disability, Involuntary Termination without Cause, or death, the PRSUs granted under this Agreement automatically will terminate and be cancelled on the date of such termination of employment.

8. Dividend Equivalents.

(a) After the Performance Period has ended (or, if a Change in Control occurs during the Performance Period, the effective date of the Change in Control), dividend equivalents (“Dividend Equivalents”) will be calculated and credited to the account of the Employee with respect to the percentage of PRSUs that are earned (or payable in accordance with Section 9 in the event of a Change in Control). Dividend Equivalents will be credited as additional PRSUs, the number of which will be equal to the number of whole Shares that could be purchased with the amount of the Dividend Equivalents, based on the Fair Market Value of the Shares as of the dividend payment date and the number of earned PRSUs (or target PRSUs in accordance with Section 9 in the event of a Change in Control).

(b) Any Dividend Equivalents credited to the Employee’s account pursuant to this Section 8 shall not be vested or paid until the dates of vesting or payment of the PRSUs with respect to which such Dividend Equivalents are credited, and such Dividend Equivalents shall be subject to the same restrictions and other terms and conditions as apply to the PRSUs with respect to which they were credited.

(c) No Dividend Equivalents shall be credited to the Employee with respect to record dates occurring prior to the Grant Date or with respect to record dates occurring on or after the date, if any, on which the PRSUs are cancelled and terminated.

9. Change in Control.

(a) No Termination of Employment Prior to a Change in Control.

(i) Notwithstanding anything to the contrary in the Plan, this Agreement, or the Employee’s employment agreement or any other agreement to which the Employee is a party, if a Change in

2020 Omnibus Performance Restricted Stock Unit 2

Control occurs during the Performance Period and the Employee’s employment does not terminate before the effectiveness of the Change in Control, then the Employee shall be entitled to the target PRSUs, which automatically will convert into a contractual right to receive a cash payment (the “Cash Payment Right”) in an amount equal to (i) the number of target PRSUs (including any additional PRSUs determined in accordance with Section 8(a)), multiplied by (ii) the per Share Fair Market Value as of the trading day immediately preceding the effective date of the Change in Control. After such conversion, no interest or Dividend Equivalents will be accrued, credited or paid with respect to the Cash Payment Right. Any portion of the PRSUs that is not converted into the Cash Payment Right automatically shall terminate and be cancelled immediately prior to the effectiveness of the Change in Control, without the payment of any consideration therefor.

(ii) Notwithstanding anything to the contrary in the Plan, this Agreement, or the Employee’s employment agreement or any other agreement to which the Employee is a party, the Cash Payment Right shall be paid as soon as practicable (but in any event within 75 days) after the last day of the Performance Period set forth in Section 2(a), provided that the Employee remains continuously employed by the Company or an Affiliate or any successor thereto through the last day of such Performance Period. Notwithstanding the immediately preceding sentence, in the event that the Employee experiences a termination of employment due to the Employee’s Retirement (as defined below), Disability, or death or an involuntary termination of employment by action of the Company (or its successor) (other than a termination due to Cause) or due to the Employee’s resignation for Good Reason prior to the last day of the Performance Period set forth in Section 2(a), the Cash Payment Right will be paid in accordance with the first sentence of this Section 9(a)(ii) as though the Employee remained continuously employed by the Company or an Affiliate or any successor thereto through the last day of the Performance Period.

(b) Certain Terminations of Employment Prior to a Change in Control. Solely for purposes of Sections 5 and 6 of the Agreement, if the Employee’s employment terminates for any of the reasons set forth in such Sections 5 and 6 prior to a Change in Control and a Change in Control occurs during the Performance Period, then the Employee shall be entitled to the target PRSUs in lieu of any amount set forth in Section 5 or Section 6, as applicable, which PRSUs automatically shall convert into a contractual right to receive the Cash Payment Right. After such conversion, no interest or Dividend Equivalents will be accrued, credited or paid with respect to the Cash Payment Right. For the avoidance of doubt, the Cash Payment Right will be paid at such time provided under Section 4.

10. Definitions.

(a) “Involuntary Termination without Cause” shall mean that the Employee experiences a termination of employment due to the Employee’s (i) receipt of a written notification that his or her position is being eliminated as a result of a structured job elimination program or (ii) resignation for a Pre-Change in Control Good Reason.

(b) “Pre-Change in Control Good Reason” shall mean that an applicable event occurs and the Employee provides notice to the Company of the existence of the event within 90 days of the initial existence of the event, the Company fails to cure the event within 30 days of such notice and the Employee resigns within 30 days following the last day of such 30-day cure period. The applicable events are any one or more of the following: (i) a material diminution in the Employee’s base compensation and (ii) a material diminution in the Employee’s authority, duties, or responsibilities.

(c) “Retirement” shall mean the Employee’s employment terminates (with the consent of the Company) after he or she has reached age 55 and the Employee’s age, in whole years, added to the number of whole years of the Employee’s continuous employment with the Company total 65 or more.

11. Nontransferability of PRSUs. The PRSUs shall not be assignable, alienable, saleable or transferable by the Employee other than by will or the laws of descent and distribution prior to settlement of the Awards pursuant to Section 3 (or, if applicable, Section 9); provided, however, that the Employee shall be entitled, in the manner provided in Section 13 hereof, to designate a beneficiary to receive any Shares or cash issuable with respect to the Award upon the death of the Employee.

2020 Omnibus Performance Restricted Stock Unit 3

12. Tax Withholding. The Company may deduct and withhold from any cash otherwise payable to the Employee such amount as may be required for the purpose of satisfying the Company’s obligation to withhold federal, state or local taxes. Further, in the event the amount so withheld is insufficient for such purpose, the Company may require that the Employee pay to the Company upon its demand or otherwise make arrangements satisfactory to the Company for payment of, such amount as may be requested by the Company in order to satisfy its obligation to withhold any such taxes.

The Employee shall be permitted to satisfy the Company’s tax withholding requirements by making a written election (in accordance with such rules and regulations and in such form as the Committee may determine) to have the Company withhold Shares otherwise issuable to the Employee (the “Withholding Election”) having a Fair Market Value on the date income is recognized (the “Tax Date”) pursuant to the settlement of the Award equal to the minimum amount required to be withheld (or such other applicable rate permitted by the Company that avoids adverse treatment for financial accounting purposes). If the number of Shares withheld to satisfy withholding tax requirements shall include a fractional Share, the number of Shares withheld shall be reduced to the next lower whole number and the Employee shall deliver cash in lieu of such fractional Share, or otherwise make arrangements satisfactory to the Company for payment of such amount. A Withholding Election must be received by the Corporate Secretary of the Company on or prior to the Tax Date.

13. Designation of Beneficiary. The Employee shall be permitted to designate one or more beneficiaries (each, a “Beneficiary”) on a Company-approved form who shall be entitled to payouts hereunder, to the extent payouts are made, after the death of the Employee. The terms and conditions of any such designation (including any changes thereto by the Employee) shall be subject to the terms and conditions of such Company-approved beneficiary designation form. If no such beneficiary designation is in effect at the time of the Employee’s death, or if no designated Beneficiary survives the Employee or if such designation conflicts with law, the Employee’s estate acting through his or her legal representative shall be entitled to receive payouts hereunder, to the extent they are made, after the death of the Employee. If the Committee is in doubt as to the right of any person to the PRSUs or any payout thereunder, the Company may refuse to settle such matter, without liability for any interest or dividends on the PRSUs, until the Committee determines the person entitled to the PRSUs or any payout thereunder, or the Company may apply to any court of appropriate jurisdiction and such application shall be a complete discharge of the liability of the Company therefor.

14. Transfer Restriction. Any Shares delivered pursuant to Section 3 hereof shall thereafter be freely transferable by the Employee, provided that the Employee agrees for himself or herself and his or her heirs, legatees and legal representatives, with respect to all Shares acquired pursuant to the terms and conditions of this Agreement (or any Shares issued pursuant to a stock dividend or stock split thereon or any securities issued in lieu thereof or in substitution or exchange therefor), that he or she and his or her heirs, legatees and legal representatives will not sell or otherwise dispose of such shares except pursuant to a registration statement filed by the Company with the Securities and Exchange Commission under the Securities Act of 1933, as amended (the “Act”), or except in a transaction which is determined by counsel to the Company to be exempt from registration under the Act and any applicable state securities laws; and to execute and deliver to the Company such investment representations and warranties, and to take such other actions, as counsel for the Company determines may be necessary or appropriate for compliance with the Act and any other applicable securities laws. The Employee agrees that any certificates representing any of the Shares acquired pursuant to the terms and conditions of this Agreement may bear such legend or legends as the Company deems appropriate in order to assure compliance with applicable securities laws.

15. Status of Employee. The Employee shall not be deemed for any purposes to be a shareowner of the Company with respect to any of the PRSUs except to the extent that the Company has delivered Shares pursuant to Section 3 hereof. Therefore, the Employee will not have the right of shareowners to vote or, subject to Section 8, to receive dividends or distributions of any kind prior to the Company delivering Shares pursuant to Section 3 hereof. Neither the Plan nor the PRSUs shall confer upon the Employee any right to continue as an employee of the Company or any of its Affiliates, nor to interfere in any way with the right of the Company to terminate the employment or directorship of the Employee at any time.

16. Powers of the Company Not Affected. The existence of the PRSUs shall not affect in any way the right or power of the Company or its shareowners to make or authorize any or all adjustments, recapitalizations, reorganizations or other changes in the Company’s capital structure or its business, or any merger or

2020 Omnibus Performance Restricted Stock Unit 4

consolidation of the Company, or any issuance of bonds, debentures, preferred or prior preference stock senior to or affecting the Shares or the rights thereof, or dissolution or liquidation of the Company, or any sale or transfer of all or any part of the Company’s assets or business or any other corporate act or proceeding, whether of a similar character or otherwise.

17. Interpretation by the Committee. As a condition of the granting of the PRSUs, the Employee agrees, for himself or herself and for his or her legal representatives or guardians, that this Agreement shall be interpreted by the Committee and that any interpretation by the Committee of the terms of this Agreement and any determination made by the Committee pursuant to this Agreement shall be final, binding and conclusive.

18. Miscellaneous.

(a) This Agreement shall be governed and construed in accordance with the internal laws of the State of Wisconsin applicable to contracts made and to be performed therein between residents thereof. As a condition of the granting of the PRSUs, the Employee irrevocably consents to the nonexclusive jurisdiction and venue of the state and federal courts located in the State of Wisconsin.

(b) The Plan and this Agreement set forth the entire understanding between the Company and the Employee with respect to the subject matter hereof and shall supersede in all respects, and the Employee hereby waives all rights under, any prior or other agreement or understanding between the parties with respect to such subject matter, including, but not limited to, any Key Executive Employment and Severance Agreement. For the avoidance of doubt, the Plan and this Agreement shall control in the event there is any express conflict between the Plan and this Agreement and any prior or other agreement or understanding between the parties.

(c) This Agreement may not be amended or modified except by the written consent of the parties hereto. Notwithstanding the foregoing, the Committee need not obtain Employee (or other interested party) consent for any such action: (i) to the extent the action is deemed necessary by the Committee to comply with any applicable law; (ii) to the extent the action is deemed necessary by the Committee to preserve favorable accounting or tax treatment for the Company of any Award; (iii) to the extent the Committee determines that such action does not materially and adversely affect the value of an Award or that such action is in the best interest of the affected Employee; or (iv) to the extent unilateral action by the Committee is permitted under Section 14(c) of the Plan.

(d) The Award and any Shares or cash issued thereunder shall be subject to potential cancellation, rescission, payback, recoupment or other action in accordance with the terms of any Company clawback policy (the “Clawback Policy”), as then in effect and as it may be amended from time to time, to the extent the Clawback Policy applies to the Award and any Shares or cash issued thereunder (including a Clawback Policy implemented or amendments made thereto after the Grant Date for the Award). By accepting the PRSUs, the Employee agrees to execute any additional documents as may be requested by the Company to effect the Company’s application, implementation and adoption of a Clawback Policy with respect to the Award and any Shares or cash issued thereunder.

(e) The captions of this Agreement are inserted for convenience of reference only and shall not be taken into account in construing this Agreement.

* * *

[The signatures to this Agreement are on the next page.]

2020 Omnibus Performance Restricted Stock Unit 5

IN WITNESS WHEREOF, the Company has caused this Agreement to be executed by its duly authorized officer and the Employee has hereunto affixed his or her hand as of the day and year first above written.

ALLIANT ENERGY CORPORATION
(the “Company”)
By:
Its:
EMPLOYEE:
Employee's Signature
	###PARTICIPANT_NAME###
Employee's Printed Name

2020 Omnibus Performance Restricted Stock Unit 6

EXHIBIT 1

PERFORMANCE RESTRICTED STOCK UNIT GRANT - PERFORMANCE GOALS

1. Purpose: The purpose of this Exhibit 1 is to set forth the Performance Goal or Goals that will be applied to determine the amount of the Award that will be earned under the terms of the attached Performance Restricted Stock Unit Agreement (the “Agreement”). This Exhibit 1 is incorporated into and forms a part of the Agreement.

PARTICIPANT_NAME	20__
Grant Date	###GRANT_DATE###
Grant Date Fair Market Value	###MARKET_PRICE_AT_TIME_OF_GRANT###
PRSUs (Target)	###TOTAL_AWARDS###
Performance Period	###DATE### through ###DATE###

2. Performance Goal: The Award will be based on the Company’s cumulative Net Income from Continuing Operations during the performance period (“Cumulative Net Income from Continuing Operations”). To determine whether the Performance Goal is satisfied, Net Income from Continuing Operations will be calculated excluding the effects of the following, if the amount is over $4,000,000 on a pre-tax basis and is not considered in the annual budget approved by the Board: (i) charges for reorganizing and restructuring; (ii) discontinued operations; (iii) asset write-downs; (iv) gains or losses on the disposition of an asset or business; (v) mergers, acquisitions or dispositions; and (vi) extraordinary, unusual and/or non-recurring items of gain or loss, that in all of the foregoing the Company identifies in its audited financial statements, including notes to the financial statements (i.e., footnotes), or the Management’s Discussion and Analysis section of the Company’s periodic reports.

3. Amount of Award: Actual awards will be based on Company performance as specified above and can range from ___ to ___ percent of target PRSUs granted. Subject to Section 9 of the Agreement, the number of PRSUs earned by the Employee shall be determined in accordance with the following schedule:

Cumulative Net Income from Continuing Operations (Millions)	Percentage of Units Earned
$____ or Greater	___%
$____	___%
$____	___%
$____	___%
Below $____	___%

PRSUs will be prorated for achievement of performance between the performance targets: If Cumulative Net Income from Continuing Operations is between any two data points, the corresponding percentage of PRSUs earned shall be determined by interpolation between the corresponding data points.

2020 Omnibus Performance Restricted Stock Unit 7

EX-31.1

Exhibit 31.1

Certification of the Chief Executive Officer for Alliant Energy Corporation

I, John O. Larsen, certify that:

1. I have reviewed this quarterly report on Form 10-Q of Alliant Energy Corporation;

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: August 7, 2020

/s/ John O. Larsen

John O. Larsen

Chairman, President and Chief Executive Officer

EX-31.2

Exhibit 31.2

Certification of the Chief Financial Officer for Alliant Energy Corporation

I, Robert J. Durian, certify that:

1. I have reviewed this quarterly report on Form 10-Q of Alliant Energy Corporation;

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: August 7, 2020

/s/ Robert J. Durian

Robert J. Durian

Executive Vice President and Chief Financial Officer

EX-31.3

Exhibit 31.3

Certification of the Chief Executive Officer for Interstate Power and Light Company

I, John O. Larsen, certify that:

1. I have reviewed this quarterly report on Form 10-Q of Interstate Power and Light Company;

2. Based on my knowledge, this report does not contain any untrue statement of a material fact or omit to state a material fact necessary to make the statements made, in light of the circumstances under which such statements were made, not misleading with respect to the period covered by this report;

3. Based on my knowledge, the financial statements, and other financial information included in this report, fairly present in all material respects the financial condition, results of operations and cash flows of the registrant as of, and for, the periods presented in this report;

4. The registrant’s other certifying officer(s) and I are responsible for establishing and maintaining disclosure controls and procedures (as defined in Exchange Act Rules 13a-15(e) and 15d-15(e)) and internal control over financial reporting (as defined in Exchange Act Rules 13a-15(f) and 15d-15(f)) for the registrant and have:

a) Designed such disclosure controls and procedures, or caused such disclosure controls and procedures to be designed under our supervision, to ensure that material information relating to the registrant, including its consolidated subsidiaries, is made known to us by others within those entities, particularly during the period in which this report is being prepared;

b) Designed such internal control over financial reporting, or caused such internal control over financial reporting to be designed under our supervision, to provide reasonable assurance regarding the reliability of financial reporting and the preparation of financial statements for external purposes in accordance with generally accepted accounting principles;

c) Evaluated the effectiveness of the registrant’s disclosure controls and procedures and presented in this report our conclusions about the effectiveness of the disclosure controls and procedures, as of the end of the period covered by this report based on such evaluation; and

d) Disclosed in this report any change in the registrant’s internal control over financial reporting that occurred during the registrant’s most recent fiscal quarter (the registrant’s fourth fiscal quarter in the case of an annual report) that has materially affected, or is reasonably likely to materially affect, the registrant’s internal control over financial reporting; and

5. The registrant’s other certifying officer(s) and I have disclosed, based on our most recent evaluation of internal control over financial reporting, to the registrant’s auditors and the audit committee of the registrant’s board of directors (or persons performing the equivalent functions):

a) All significant deficiencies and material weaknesses in the design or operation of internal control over financial reporting which are reasonably likely to adversely affect the registrant’s ability to record, process, summarize and report financial information; and

b) Any fraud, whether or not material, that involves management or other employees who have a significant role in the registrant’s internal control over financial reporting.

Date: August 7, 2020

/s/ John O. Larsen

John O. Larsen

Chairman and Chief Executive Officer

EX-31.4

Exhibit 31.4

Certification of the Chief Financial Officer for Interstate Power and Light Company

I, Robert J. Durian, certify that:

1. I have reviewed this quarterly report on Form 10-Q of Interstate Power and Light Company;

2. Based on my knowledge, this report does not contain any untrue statement of a material fact or omit to state a material fact necessary to make the statements made, in light of the circumstances under which such statements were made, not misleading with respect to the period covered by this report;

3. Based on my knowledge, the financial statements, and other financial information included in this report, fairly present in all material respects the financial condition, results of operations and cash flows of the registrant as of, and for, the periods presented in this report;

4. The registrant’s other certifying officer(s) and I are responsible for establishing and maintaining disclosure controls and procedures (as defined in Exchange Act Rules 13a-15(e) and 15d-15(e)) and internal control over financial reporting (as defined in Exchange Act Rules 13a-15(f) and 15d-15(f)) for the registrant and have:

a) Designed such disclosure controls and procedures, or caused such disclosure controls and procedures to be designed under our supervision, to ensure that material information relating to the registrant, including its consolidated subsidiaries, is made known to us by others within those entities, particularly during the period in which this report is being prepared;

b) Designed such internal control over financial reporting, or caused such internal control over financial reporting to be designed under our supervision, to provide reasonable assurance regarding the reliability of financial reporting and the preparation of financial statements for external purposes in accordance with generally accepted accounting principles;

c) Evaluated the effectiveness of the registrant’s disclosure controls and procedures and presented in this report our conclusions about the effectiveness of the disclosure controls and procedures, as of the end of the period covered by this report based on such evaluation; and

d) Disclosed in this report any change in the registrant’s internal control over financial reporting that occurred during the registrant’s most recent fiscal quarter (the registrant’s fourth fiscal quarter in the case of an annual report) that has materially affected, or is reasonably likely to materially affect, the registrant’s internal control over financial reporting; and

5. The registrant’s other certifying officer(s) and I have disclosed, based on our most recent evaluation of internal control over financial reporting, to the registrant’s auditors and the audit committee of the registrant’s board of directors (or persons performing the equivalent functions):

a) All significant deficiencies and material weaknesses in the design or operation of internal control over financial reporting which are reasonably likely to adversely affect the registrant’s ability to record, process, summarize and report financial information; and

b) Any fraud, whether or not material, that involves management or other employees who have a significant rolein the registrant’s internal control over financial reporting.

Date: August 7, 2020

/s/ Robert J. Durian

Robert J. Durian

Executive Vice President and Chief Financial Officer

EX-31.5

Exhibit 31.5

Certification of the Chief Executive Officer for Wisconsin Power and Light Company

I, John O. Larsen, certify that:

1. I have reviewed this quarterly report on Form 10-Q of Wisconsin Power and Light Company;

2. Based on my knowledge, this report does not contain any untrue statement of a material fact or omit to state a material fact necessary to make the statements made, in light of the circumstances under which such statements were made, not misleading with respect to the period covered by this report;

3. Based on my knowledge, the financial statements, and other financial information included in this report, fairly present in all material respects the financial condition, results of operations and cash flows of the registrant as of, and for, the periods presented in this report;

4. The registrant’s other certifying officer(s) and I are responsible for establishing and maintaining disclosure controls and procedures (as defined in Exchange Act Rules 13a-15(e) and 15d-15(e)) and internal control over financial reporting (as defined in Exchange Act Rules 13a-15(f) and 15d-15(f)) for the registrant and have:

a) Designed such disclosure controls and procedures, or caused such disclosure controls and procedures to be designed under our supervision, to ensure that material information relating to the registrant, including its consolidated subsidiaries, is made known to us by others within those entities, particularly during the period in which this report is being prepared;

b) Designed such internal control over financial reporting, or caused such internal control over financial reporting to be designed under our supervision, to provide reasonable assurance regarding the reliability of financial reporting and the preparation of financial statements for external purposes in accordance with generally accepted accounting principles;

c) Evaluated the effectiveness of the registrant’s disclosure controls and procedures and presented in this report our conclusions about the effectiveness of the disclosure controls and procedures, as of the end of the period covered by this report based on such evaluation; and

d) Disclosed in this report any change in the registrant’s internal control over financial reporting that occurred during the registrant’s most recent fiscal quarter (the registrant’s fourth fiscal quarter in the case of an annual report) that has materially affected, or is reasonably likely to materially affect, the registrant’s internal control over financial reporting; and

5. The registrant’s other certifying officer(s) and I have disclosed, based on our most recent evaluation of internal control over financial reporting, to the registrant’s auditors and the audit committee of the registrant’s board of directors (or persons performing the equivalent functions):

a) All significant deficiencies and material weaknesses in the design or operation of internal control over financial reporting which are reasonably likely to adversely affect the registrant’s ability to record, process, summarize and report financial information; and

b) Any fraud, whether or not material, that involves management or other employees who have a significant role in the registrant’s internal control over financial reporting.

Date: August 7, 2020

/s/ John O. Larsen

John O. Larsen

Chairman and Chief Executive Officer

EX-31.6

Exhibit 31.6

Certification of the Chief Financial Officer for Wisconsin Power and Light Company

I, Robert J. Durian, certify that:

1. I have reviewed this quarterly report on Form 10-Q of Wisconsin Power and Light Company;

2. Based on my knowledge, this report does not contain any untrue statement of a material fact or omit to state a material fact necessary to make the statements made, in light of the circumstances under which such statements were made, not misleading with respect to the period covered by this report;

3. Based on my knowledge, the financial statements, and other financial information included in this report, fairly present in all material respects the financial condition, results of operations and cash flows of the registrant as of, and for, the periods presented in this report;

4. The registrant’s other certifying officer(s) and I are responsible for establishing and maintaining disclosure controls and procedures (as defined in Exchange Act Rules 13a-15(e) and 15d-15(e)) and internal control over financial reporting (as defined in Exchange Act Rules 13a-15(f) and 15d-15(f)) for the registrant and have:

a) Designed such disclosure controls and procedures, or caused such disclosure controls and procedures to be designed under our supervision, to ensure that material information relating to the registrant, including its consolidated subsidiaries, is made known to us by others within those entities, particularly during the period in which this report is being prepared;

b) Designed such internal control over financial reporting, or caused such internal control over financial reporting to be designed under our supervision, to provide reasonable assurance regarding the reliability of financial reporting and the preparation of financial statements for external purposes in accordance with generally accepted accounting principles;

c) Evaluated the effectiveness of the registrant’s disclosure controls and procedures and presented in this report our conclusions about the effectiveness of the disclosure controls and procedures, as of the end of the period covered by this report based on such evaluation; and

d) Disclosed in this report any change in the registrant’s internal control over financial reporting that occurred during the registrant’s most recent fiscal quarter (the registrant’s fourth fiscal quarter in the case of an annual report) that has materially affected, or is reasonably likely to materially affect, the registrant’s internal control over financial reporting; and

5. The registrant’s other certifying officer(s) and I have disclosed, based on our most recent evaluation of internal control over financial reporting, to the registrant’s auditors and the audit committee of the registrant’s board of directors (or persons performing the equivalent functions):

a) All significant deficiencies and material weaknesses in the design or operation of internal control over financial reporting which are reasonably likely to adversely affect the registrant’s ability to record, process, summarize and report financial information; and

b) Any fraud, whether or not material, that involves management or other employees who have a significant role in the registrant’s internal control over financial reporting.

Date: August 7, 2020

/s/ Robert J. Durian

Robert J. Durian

Executive Vice President and Chief Financial Officer

EX-32.1

Exhibit 32.1

Written Statement of the Chief Executive Officer and Chief Financial Officer

Pursuant to 18 U.S.C. §1350

Solely for the purposes of complying with 18 U.S.C. §1350, as adopted pursuant to Section 906 of the Sarbanes-Oxley Act of 2002, we, the undersigned Chief Executive Officer and Chief Financial Officer of Alliant Energy Corporation (the “Company”), hereby certify, based on our knowledge, that the Quarterly Report on Form 10-Q of the Company for the quarter ended June 30, 2020 (the “Report”) fully complies with the requirements of Section 13(a) of the Securities Exchange Act of 1934 and that information contained in the Report fairly presents, in all material respects, the financial condition and results of operations of the Company.

/s/ John O. Larsen

John O. Larsen

Chairman, President and Chief Executive Officer

/s/ Robert J. Durian

Robert J. Durian

Executive Vice President and Chief Financial Officer

August 7, 2020

EX-32.2

Exhibit 32.2

Written Statement of the Chief Executive Officer and Chief Financial Officer

Pursuant to 18 U.S.C. §1350

Solely for the purposes of complying with 18 U.S.C. §1350, as adopted pursuant to Section 906 of the Sarbanes-Oxley Act of 2002, we, the undersigned Chief Executive Officer and Chief Financial Officer of Interstate Power and Light Company (the “Company”), hereby certify, based on our knowledge, that the Quarterly Report on Form 10-Q of the Company for the quarter ended June 30, 2020 (the “Report”) fully complies with the requirements of Section 13(a) of the Securities Exchange Act of 1934 and that information contained in the Report fairly presents, in all material respects, the financial condition and results of operations of the Company.

/s/ John O. Larsen

John O. Larsen

Chairman and Chief Executive Officer

/s/ Robert J. Durian

Robert J. Durian

Executive Vice President and Chief Financial Officer

August 7, 2020

EX-32.3

Exhibit 32.3

Written Statement of the Chief Executive Officer and Chief Financial Officer

Pursuant to 18 U.S.C. §1350

Solely for the purposes of complying with 18 U.S.C. §1350, as adopted pursuant to Section 906 of the Sarbanes-Oxley Act of 2002, we, the undersigned Chief Executive Officer and Chief Financial Officer of Wisconsin Power and Light Company (the “Company”), hereby certify, based on our knowledge, that the Quarterly Report on Form 10-Q of the Company for the quarter ended June 30, 2020 (the “Report”) fully complies with the requirements of Section 13(a) of the Securities Exchange Act of 1934 and that information contained in the Report fairly presents, in all material respects, the financial condition and results of operations of the Company.

/s/ John O. Larsen

John O. Larsen

Chairman and Chief Executive Officer

/s/ Robert J. Durian

Robert J. Durian

Executive Vice President and Chief Financial Officer

August 7, 2020

XML

Document And Entity Information	6 Months Ended
	Jun. 30, 2020 shares
Entity Information [Line Items]
Document Type	10-Q
Document Quarterly Report	true
Document Period End Date	Jun. 30, 2020
Document Transition Report	false
Entity Registrant Name	ALLIANT ENERGY CORP
Entity Central Index Key	0000352541
Entity Incorporation, State or Country Code	WI
Entity Address, Address Line One	4902 N. Biltmore Lane
Entity Address, City or Town	Madison
Entity Address, State or Province	WI
Entity Address, Postal Zip Code	53718
City Area Code	608
Local Phone Number	458-3311
Entity File Number	1-9894
Entity Tax Identification Number	39-1380265
Title of 12(b) Security	Common Stock, $0.01 Par Value
Trading Symbol	LNT
Security Exchange Name	NASDAQ
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Large Accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
Entity Shell Company	false
Entity Common Stock, Shares Outstanding	249,644,352
Current Fiscal Year End Date	--12-31
Document Fiscal Year Focus	2020
Document Fiscal Period Focus	Q2
Amendment Flag	false
IPL [Member]
Entity Information [Line Items]
Entity Registrant Name	INTERSTATE POWER & LIGHT CO
Entity Central Index Key	0000052485
Entity Incorporation, State or Country Code	IA
Entity Address, Address Line One	Alliant Energy Tower
Entity Address, City or Town	Cedar Rapids
Entity Address, State or Province	IA
Entity Address, Postal Zip Code	52401
City Area Code	319
Local Phone Number	786-4411
Entity File Number	1-4117
Entity Tax Identification Number	42-0331370
Title of 12(b) Security	5.100% Series D Cumulative Perpetual Preferred Stock, $0.01 Par Value
Trading Symbol	IPLDP
Security Exchange Name	NASDAQ
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Non-accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
Entity Shell Company	false
Entity Common Stock, Shares Outstanding	13,370,788
WPL [Member]
Entity Information [Line Items]
Entity Registrant Name	WISCONSIN POWER & LIGHT CO
Entity Central Index Key	0000107832
Entity Incorporation, State or Country Code	WI
Entity Address, Address Line One	4902 N. Biltmore Lane
Entity Address, City or Town	Madison
Entity Address, State or Province	WI
Entity Address, Postal Zip Code	53718
City Area Code	608
Local Phone Number	458-3311
Entity File Number	0-337
Entity Tax Identification Number	39-0714890
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Non-accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
Entity Shell Company	false
Entity Common Stock, Shares Outstanding	13,236,601

XML

Condensed Consolidated Statements Of Income - USD ($) shares in Millions, $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Revenues:
Electric utility	$ 675.2	$ 691.2	$ 1,405.5	$ 1,434.6
Gas utility	58.9	65.2	211.1	281.0
Other utility	10.1	10.9	21.7	22.0
Non-utility	18.9	22.9	40.5	39.8
Total revenues	763.1	790.2	1,678.8	1,777.4
Operating expenses:
Electric production fuel and purchased power	163.5	164.8	347.6	383.2
Electric transmission service	71.6	112.4	193.8	235.4
Cost of gas sold	20.9	20.4	105.9	142.0
Other operation and maintenance	159.8	172.3	322.0	353.5
Depreciation and amortization	152.1	142.9	298.4	279.8
Taxes other than income taxes	27.1	27.6	54.7	56.9
Total operating expenses	595.0	640.4	1,322.4	1,450.8
Operating income	168.1	149.8	356.4	326.6
Other (income) and deductions:
Interest expense	69.6	69.2	138.5	135.5
Equity income from unconsolidated investments, net	(17.4)	(12.7)	(30.8)	(23.6)
Allowance for funds used during construction	(15.2)	(18.3)	(38.2)	(43.7)
Other	2.5	3.3	4.4	7.3
Total other (income) and deductions	39.5	41.5	73.9	75.5
Income before income taxes	128.6	108.3	282.5	251.1
Income tax expense (benefit)	(8.3)	11.2	(27.0)	26.3
Net income	136.9	97.1	309.5	224.8
Preferred dividend requirements of Interstate Power and Light Company	2.5	2.5	5.1	5.1
Net income attributable to common shareowners	$ 134.4	$ 94.6	$ 304.4	$ 219.7
Weighted average number of common shares outstanding:
Basic (in shares)	249.6	237.5	247.0	237.0
Diluted (in shares)	249.8	238.1	247.2	237.3
Earnings per weighted average common share attributable to Alliant Energy common shareowners (basic and diluted) (in dollars per share)	$ 0.54	$ 0.40	$ 1.23	$ 0.93
IPL [Member]
Revenues:
Electric utility	$ 388.4	$ 392.3	$ 813.2	$ 812.1
Gas utility	33.9	38.4	116.9	163.0
Other utility	9.6	10.5	20.7	21.2
Total revenues	431.9	441.2	950.8	996.3
Operating expenses:
Electric production fuel and purchased power	96.0	83.3	202.2	212.2
Electric transmission service	34.0	77.4	118.5	165.1
Cost of gas sold	12.4	10.8	56.6	74.1
Other operation and maintenance	97.5	97.4	184.1	205.4
Depreciation and amortization	88.7	82.6	174.6	159.7
Taxes other than income taxes	14.6	15.2	29.4	31.8
Total operating expenses	343.2	366.7	765.4	848.3
Operating income	88.7	74.5	185.4	148.0
Other (income) and deductions:
Interest expense	34.8	31.5	69.3	60.9
Allowance for funds used during construction	(5.6)	(7.9)	(15.4)	(23.7)
Other	1.0	1.5	1.9	3.4
Total other (income) and deductions	30.2	25.1	55.8	40.6
Income before income taxes	58.5	49.4	129.6	107.4
Income tax expense (benefit)	(3.8)	1.9	(17.9)	4.0
Net income	62.3	47.5	147.5	103.4
Preferred dividend requirements of Interstate Power and Light Company	2.5	2.5	5.1	5.1
Net income attributable to common shareowners	59.8	45.0	142.4	98.3
WPL [Member]
Revenues:
Electric utility	286.8	298.9	592.3	622.5
Gas utility	25.0	26.8	94.2	118.0
Other utility	0.5	0.4	1.0	0.8
Total revenues	312.3	326.1	687.5	741.3
Operating expenses:
Electric production fuel and purchased power	67.5	81.5	145.4	171.0
Electric transmission service	37.6	35.0	75.3	70.3
Cost of gas sold	8.5	9.6	49.3	67.9
Other operation and maintenance	53.2	62.4	107.4	125.9
Depreciation and amortization	62.0	59.1	121.1	117.7
Taxes other than income taxes	11.8	11.5	23.5	23.4
Total operating expenses	240.6	259.1	522.0	576.2
Operating income	71.7	67.0	165.5	165.1
Other (income) and deductions:
Interest expense	27.3	26.1	52.4	51.9
Allowance for funds used during construction	(9.5)	(10.4)	(22.7)	(20.0)
Other	0.8	1.6	1.3	3.2
Total other (income) and deductions	18.6	17.3	31.0	35.1
Income before income taxes	53.1	49.7	134.5	130.0
Income tax expense (benefit)	(4.5)	7.7	(12.7)	22.3
Net income	$ 57.6	$ 42.0	$ 147.2	$ 107.7

XML

Condensed Consolidated Balance Sheets - USD ($) $ in Millions	Jun. 30, 2020	Dec. 31, 2019
Current assets:
Cash and cash equivalents	$ 208.1	$ 16.3
Accounts receivable, less allowance for expected credit losses	386.5	402.1
Production fuel, at weighted average cost	78.0	77.7
Gas stored underground, at weighted average cost	36.8	49.1
Materials and supplies, at weighted average cost	107.0	100.5
Regulatory assets	94.5	86.4
Other	133.4	143.4
Total current assets	1,044.3	875.5
Property, plant and equipment, net	13,936.4	13,527.1
Investments:
ATC Holdings	326.1	320.1
Other	147.1	147.7
Total investments	473.2	467.8
Other assets:
Regulatory assets	1,748.5	1,758.3
Deferred charges and other	67.3	72.0
Total other assets	1,815.8	1,830.3
Total assets	17,269.7	16,700.7
Current liabilities:
Current maturities of long-term debt	7.4	657.2
Commercial paper	185.4	337.4
Accounts payable	429.9	422.3
Regulatory liabilities	211.4	212.0
Other	386.8	425.2
Total current liabilities	1,220.9	2,054.1
Long-term debt, net (excluding current portion)	6,572.4	5,533.0
Other liabilities:
Deferred tax liabilities	1,761.3	1,714.0
Regulatory liabilities	1,159.6	1,211.6
Pension and other benefit obligations	450.2	484.0
Other	357.0	298.9
Total other liabilities	3,728.1	3,708.5
Commitments and contingencies (Note 13)
Common equity:
Common stock	2.5	2.5
Additional paid-in capital	2,683.1	2,445.9
Retained earnings	2,873.5	2,765.4
Accumulated other comprehensive income (loss)	(0.6)	1.3
Shares in deferred compensation trust - 367,493 and 381,232 shares at a weighted average cost of $27.86 and $26.24 per share	(10.2)	(10.0)
Total common equity	5,548.3	5,205.1
Cumulative preferred stock of Interstate Power and Light Company	200.0	200.0
Total equity	5,748.3	5,405.1
Total liabilities and equity	17,269.7	16,700.7
IPL [Member]
Current assets:
Cash and cash equivalents	203.5	9.3
Accounts receivable, less allowance for expected credit losses	208.9	202.8
Production fuel, at weighted average cost	54.8	47.1
Gas stored underground, at weighted average cost	10.4	21.7
Materials and supplies, at weighted average cost	60.4	55.0
Regulatory assets	54.0	43.5
Other	32.5	30.0
Total current assets	624.5	409.4
Property, plant and equipment, net	7,666.3	7,480.7
Other assets:
Regulatory assets	1,350.9	1,355.8
Deferred charges and other	37.9	31.6
Total other assets	1,388.8	1,387.4
Total assets	9,679.6	9,277.5
Current liabilities:
Current maturities of long-term debt	0.0	200.0
Accounts payable	207.3	207.0
Regulatory liabilities	131.1	115.9
Other	293.8	307.6
Total current liabilities	632.2	830.5
Long-term debt, net (excluding current portion)	3,343.5	2,947.3
Other liabilities:
Deferred tax liabilities	1,012.7	1,008.0
Regulatory liabilities	586.8	598.8
Pension and other benefit obligations	160.1	167.7
Other	273.2	253.4
Total other liabilities	2,032.8	2,027.9
Commitments and contingencies (Note 13)
Common equity:
Common stock	33.4	33.4
Additional paid-in capital	2,522.8	2,347.8
Retained earnings	914.9	890.6
Total common equity	3,471.1	3,271.8
Cumulative preferred stock of Interstate Power and Light Company	200.0	200.0
Total equity	3,671.1	3,471.8
Total liabilities and equity	9,679.6	9,277.5
WPL [Member]
Current assets:
Cash and cash equivalents	3.2	4.4
Accounts receivable, less allowance for expected credit losses	166.9	190.9
Production fuel, at weighted average cost	23.1	30.6
Gas stored underground, at weighted average cost	26.4	27.4
Materials and supplies, at weighted average cost	44.3	43.1
Regulatory assets	40.5	42.9
Other	52.1	103.4
Total current assets	356.5	442.7
Property, plant and equipment, net	5,867.2	5,638.3
Other assets:
Regulatory assets	397.6	402.5
Deferred charges and other	27.1	23.0
Total other assets	424.7	425.5
Total assets	6,648.4	6,506.5
Current liabilities:
Current maturities of long-term debt	0.0	150.0
Commercial paper	37.9	168.2
Accounts payable	183.0	159.9
Accounts payable to associated companies	28.9	41.8
Regulatory liabilities	80.3	96.1
Other	79.5	74.3
Total current liabilities	409.6	690.3
Long-term debt, net (excluding current portion)	2,129.4	1,782.7
Other liabilities:
Deferred tax liabilities	667.4	626.2
Regulatory liabilities	572.8	612.8
Finance lease obligations - Sheboygan Falls Energy Facility	46.7	51.4
Pension and other benefit obligations	201.8	210.8
Other	168.9	168.7
Total other liabilities	1,657.6	1,669.9
Commitments and contingencies (Note 13)
Common equity:
Common stock	66.2	66.2
Additional paid-in capital	1,459.0	1,434.0
Retained earnings	926.6	863.4
Total common equity	2,451.8	2,363.6
Total equity	2,451.8	2,363.6
Total liabilities and equity	$ 6,648.4	$ 6,506.5

XML

Condensed Consolidated Balance Sheets (Parenthetical) - $ / shares	Jun. 30, 2020	Dec. 31, 2019
Common stock, par value (in dollars per share)	$ 0.01	$ 0.01
Common stock, shares authorized (in shares)	480,000,000	480,000,000
Common stock, shares outstanding (in shares)	249,644,352	245,022,800
Shares in deferred compensation trust (in shares)	367,493	381,232
Shares in deferred compensation trust, weighted average cost per share (in dollars per share)	$ 27.86	$ 26.24
IPL [Member]
Common stock, par value (in dollars per share)	$ 2.50	$ 2.50
Common stock, shares authorized (in shares)	24,000,000	24,000,000
Common stock, shares outstanding (in shares)	13,370,788	13,370,788
WPL [Member]
Common stock, par value (in dollars per share)	$ 5.00	$ 5.00
Common stock, shares authorized (in shares)	18,000,000	18,000,000
Common stock, shares outstanding (in shares)	13,236,601	13,236,601

XML

Condensed Consolidated Statements Of Cash Flows - USD ($) $ in Millions	6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019
Cash flows from operating activities:
Net income	$ 309.5	$ 224.8
Adjustments to reconcile net income to net cash flows from operating activities:
Depreciation and amortization	298.4	279.8
Deferred tax expense (benefit) and tax credits	(28.8)	19.9
Equity component of allowance for funds used during construction	(26.8)	(30.8)
Other	26.6	13.5
Other changes in assets and liabilities:
Accounts receivable	(197.9)	(199.7)
Accounts payable	8.3	(33.1)
Regulatory liabilities	(63.4)	(26.1)
Pension and other benefit obligations	(33.8)	(21.7)
Deferred income taxes	81.9	34.3
Other	(54.3)	16.0
Net cash flows from operating activities	319.7	276.9
Cash flows used for investing activities:
Utility business construction and acquisition expenditures	(584.0)	(652.5)
Other construction and acquisition expenditures	(24.3)	(54.1)
Cash receipts on sold receivables	209.9	125.5
Other	6.1	(25.9)
Net cash flows used for investing activities	(392.3)	(607.0)
Cash flows from financing activities:
Common stock dividends	(187.6)	(167.8)
Proceeds from issuance of common stock, net	234.8	60.6
Proceeds from issuance of long-term debt	1,050.0	650.0
Payments to retire long-term debt	(653.7)	(3.4)
Net change in commercial paper	(152.0)	(50.7)
Other	(27.2)	(9.9)
Net cash flows from financing activities	264.3	478.8
Net increase (decrease) in cash, cash equivalents and restricted cash	191.7	148.7
Cash, cash equivalents and restricted cash at beginning of period	17.7	25.5
Cash, cash equivalents and restricted cash at end of period	209.4	174.2
Supplemental cash flows information:
Interest	(138.1)	(132.7)
Income taxes, net	(5.0)	2.5
Significant non-cash investing and financing activities:
Accrued capital expenditures	208.3	187.4
Beneficial interest obtained in exchange for securitized accounts receivable	194.1	214.6
IPL [Member]
Cash flows from operating activities:
Net income	147.5	103.4
Adjustments to reconcile net income to net cash flows from operating activities:
Depreciation and amortization	174.6	159.7
Deferred tax expense (benefit) and tax credits	(20.9)	(11.7)
Other	(5.8)	(14.9)
Other changes in assets and liabilities:
Accounts receivable	(218.7)	(209.3)
Accounts payable	26.1	(17.0)
Deferred income taxes	25.6	25.3
Other	(51.2)	53.5
Net cash flows from operating activities	77.2	89.0
Cash flows used for investing activities:
Utility business construction and acquisition expenditures	(309.6)	(449.5)
Cash receipts on sold receivables	209.9	125.5
Other	(25.5)	(30.5)
Net cash flows used for investing activities	(125.2)	(354.5)
Cash flows from financing activities:
Common stock dividends	(118.1)	(83.9)
Capital contributions from parent	175.0	100.0
Proceeds from issuance of long-term debt	400.0	300.0
Payments to retire long-term debt	(200.0)	0.0
Net change in commercial paper	0.0	(50.4)
Other	(14.7)	(6.2)
Net cash flows from financing activities	242.2	259.5
Net increase (decrease) in cash, cash equivalents and restricted cash	194.2	(6.0)
Cash, cash equivalents and restricted cash at beginning of period	9.3	12.4
Cash, cash equivalents and restricted cash at end of period	203.5	6.4
Supplemental cash flows information:
Interest	(71.6)	(58.3)
Income taxes, net	7.3	12.1
Significant non-cash investing and financing activities:
Accrued capital expenditures	93.8	117.4
Beneficial interest obtained in exchange for securitized accounts receivable	194.1	214.6
WPL [Member]
Cash flows from operating activities:
Net income	147.2	107.7
Adjustments to reconcile net income to net cash flows from operating activities:
Depreciation and amortization	121.1	117.7
Other	(18.9)	17.0
Other changes in assets and liabilities:
Accounts receivable	23.1	7.6
Regulatory liabilities	(63.3)	(18.4)
Deferred income taxes	53.2	11.2
Other	(6.1)	(34.6)
Net cash flows from operating activities	256.3	208.2
Cash flows used for investing activities:
Utility business construction and acquisition expenditures	(274.4)	(203.0)
Other	14.6	(15.0)
Net cash flows used for investing activities	(259.8)	(218.0)
Cash flows from financing activities:
Common stock dividends	(84.0)	(72.0)
Capital contributions from parent	25.0	0.0
Proceeds from issuance of long-term debt	350.0	350.0
Payments to retire long-term debt	(150.0)	0.0
Net change in commercial paper	(130.3)	(105.5)
Other	(8.4)	(7.4)
Net cash flows from financing activities	2.3	165.1
Net increase (decrease) in cash, cash equivalents and restricted cash	(1.2)	155.3
Cash, cash equivalents and restricted cash at beginning of period	4.4	9.2
Cash, cash equivalents and restricted cash at end of period	3.2	164.5
Supplemental cash flows information:
Interest	(49.7)	(51.7)
Income taxes, net	1.1	(6.5)
Significant non-cash investing and financing activities:
Accrued capital expenditures	$ 113.7	$ 66.4

XML

Summary Of Significant Accounting Policies

6 Months Ended

Jun. 30, 2020

Summary Of Significant Accounting Policies

SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES

NOTE 1(a) General - The interim unaudited Financial Statements included herein have been prepared pursuant to the rules and regulations of the Securities and Exchange Commission. Accordingly, certain information and note disclosures normally included in financial statements prepared in accordance with GAAP have been condensed or omitted, although management believes that the disclosures are adequate to make the information presented not misleading. These Financial Statements should be read in conjunction with the financial statements and the notes thereto included in the latest combined Annual Report on Form 10-K.

In the opinion of management, all adjustments, which unless otherwise noted are normal and recurring in nature, necessary for a fair presentation of the results of operations, financial position and cash flows have been made. Results for the six months ended June 30, 2020 are not necessarily indicative of results that may be expected for the year ending December 31, 2020.

In March 2020, COVID-19 was declared a global pandemic, which has resulted in widespread travel restrictions and closures of commercial spaces and industrial facilities in Alliant Energy’s service territories. For the three and six months ended June 30, 2020, Alliant Energy, IPL and WPL considered the impact of COVID-19 on their overall business operations, financial condition, results of operations and cash flows, along with assumptions and estimates used. While the total expected impact of COVID-19 on future sales is currently unknown, Alliant Energy, IPL and WPL have experienced higher electric residential sales and lower electric commercial and industrial sales since the outset of the pandemic. The degree to which the COVID-19 pandemic may impact Alliant Energy, IPL and WPL in the future is currently unknown and will depend on future developments of the pandemic as well as possible additional actions by government and regulatory authorities.

A change in management’s estimates or assumptions could have a material impact on financial condition and results of operations during the period in which such change occurred. Certain prior period amounts in the Financial Statements and Notes have been reclassified to conform to the current period presentation for comparative purposes.

NOTE 1(b) Cash and Cash Equivalents - At June 30, 2020, Alliant Energy’s and IPL’s cash and cash equivalents included $198.3 million and $198.3 million of money market fund investments, with weighted average interest rates of 0.1% and 0.1%, respectively.

NOTE 1(c) Current Expected Credit Losses Estimates - Current expected credit losses are estimated for trade and other receivables and credit exposures on guarantees of the performance by third parties. The current expected credit losses for short-term trade receivables are based on estimates of losses resulting from the inability of customers to make required payments. The methodology used to estimate losses is based on historical write-offs, regional economic conditions, significant events that could impact collectability, such as impacts related to COVID-19 and related regulatory actions, and forecasted changes to the accounts receivable aging portfolio and write-offs. The current expected credit losses related to guarantees of the performance by third parties are estimated using both quantitative and qualitative information, which utilizes potential outcomes in a range of possible estimated amounts.

NOTE 1(d) New Accounting Standards -

Credit Losses - In June 2016, the Financial Accounting Standards Board issued an accounting standard requiring use of a current expected credit loss model rather than an incurred loss method, which is intended to result in more timely recognition of credit losses on trade receivables, certain other assets and off-balance sheet credit exposures. Alliant Energy, IPL and WPL adopted this standard on January 1, 2020 using a modified retrospective method of adoption, which required cumulative effect adjustments to retained earnings on January 1, 2020. IPL and WPL did not record a cumulative effect adjustment to retained earnings and Alliant Energy recorded a pre-tax $12 million (after-tax $8.7 million) cumulative effect adjustment to decrease retained earnings related to Alliant Energy’s guarantees in the partnership obligations of an affiliate of Whiting Petroleum (refer to Note 13(c) for further discussion). This adjustment is included in “Adoption of new accounting standard” in Alliant Energy’s summary of changes in shareowners’ equity in Note 5 for the six months ended June 30, 2020.

IPL [Member]

Summary Of Significant Accounting Policies

SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES

NOTE 1(a) General - The interim unaudited Financial Statements included herein have been prepared pursuant to the rules and regulations of the Securities and Exchange Commission. Accordingly, certain information and note disclosures normally included in financial statements prepared in accordance with GAAP have been condensed or omitted, although management believes that the disclosures are adequate to make the information presented not misleading. These Financial Statements should be read in conjunction with the financial statements and the notes thereto included in the latest combined Annual Report on Form 10-K.

In the opinion of management, all adjustments, which unless otherwise noted are normal and recurring in nature, necessary for a fair presentation of the results of operations, financial position and cash flows have been made. Results for the six months ended June 30, 2020 are not necessarily indicative of results that may be expected for the year ending December 31, 2020.

In March 2020, COVID-19 was declared a global pandemic, which has resulted in widespread travel restrictions and closures of commercial spaces and industrial facilities in Alliant Energy’s service territories. For the three and six months ended June 30, 2020, Alliant Energy, IPL and WPL considered the impact of COVID-19 on their overall business operations, financial condition, results of operations and cash flows, along with assumptions and estimates used. While the total expected impact of COVID-19 on future sales is currently unknown, Alliant Energy, IPL and WPL have experienced higher electric residential sales and lower electric commercial and industrial sales since the outset of the pandemic. The degree to which the COVID-19 pandemic may impact Alliant Energy, IPL and WPL in the future is currently unknown and will depend on future developments of the pandemic as well as possible additional actions by government and regulatory authorities.

A change in management’s estimates or assumptions could have a material impact on financial condition and results of operations during the period in which such change occurred. Certain prior period amounts in the Financial Statements and Notes have been reclassified to conform to the current period presentation for comparative purposes.

NOTE 1(b) Cash and Cash Equivalents - At June 30, 2020, Alliant Energy’s and IPL’s cash and cash equivalents included $198.3 million and $198.3 million of money market fund investments, with weighted average interest rates of 0.1% and 0.1%, respectively.

NOTE 1(c) Current Expected Credit Losses Estimates - Current expected credit losses are estimated for trade and other receivables and credit exposures on guarantees of the performance by third parties. The current expected credit losses for short-term trade receivables are based on estimates of losses resulting from the inability of customers to make required payments. The methodology used to estimate losses is based on historical write-offs, regional economic conditions, significant events that could impact collectability, such as impacts related to COVID-19 and related regulatory actions, and forecasted changes to the accounts receivable aging portfolio and write-offs. The current expected credit losses related to guarantees of the performance by third parties are estimated using both quantitative and qualitative information, which utilizes potential outcomes in a range of possible estimated amounts.

NOTE 1(d) New Accounting Standards -

Credit Losses - In June 2016, the Financial Accounting Standards Board issued an accounting standard requiring use of a current expected credit loss model rather than an incurred loss method, which is intended to result in more timely recognition of credit losses on trade receivables, certain other assets and off-balance sheet credit exposures. Alliant Energy, IPL and WPL adopted this standard on January 1, 2020 using a modified retrospective method of adoption, which required cumulative effect adjustments to retained earnings on January 1, 2020. IPL and WPL did not record a cumulative effect adjustment to retained earnings and Alliant Energy recorded a pre-tax $12 million (after-tax $8.7 million) cumulative effect adjustment to decrease retained earnings related to Alliant Energy’s guarantees in the partnership obligations of an affiliate of Whiting Petroleum (refer to Note 13(c) for further discussion). This adjustment is included in “Adoption of new accounting standard” in Alliant Energy’s summary of changes in shareowners’ equity in Note 5 for the six months ended June 30, 2020.

WPL [Member]

Summary Of Significant Accounting Policies

SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES

NOTE 1(a) General - The interim unaudited Financial Statements included herein have been prepared pursuant to the rules and regulations of the Securities and Exchange Commission. Accordingly, certain information and note disclosures normally included in financial statements prepared in accordance with GAAP have been condensed or omitted, although management believes that the disclosures are adequate to make the information presented not misleading. These Financial Statements should be read in conjunction with the financial statements and the notes thereto included in the latest combined Annual Report on Form 10-K.

In the opinion of management, all adjustments, which unless otherwise noted are normal and recurring in nature, necessary for a fair presentation of the results of operations, financial position and cash flows have been made. Results for the six months ended June 30, 2020 are not necessarily indicative of results that may be expected for the year ending December 31, 2020.

In March 2020, COVID-19 was declared a global pandemic, which has resulted in widespread travel restrictions and closures of commercial spaces and industrial facilities in Alliant Energy’s service territories. For the three and six months ended June 30, 2020, Alliant Energy, IPL and WPL considered the impact of COVID-19 on their overall business operations, financial condition, results of operations and cash flows, along with assumptions and estimates used. While the total expected impact of COVID-19 on future sales is currently unknown, Alliant Energy, IPL and WPL have experienced higher electric residential sales and lower electric commercial and industrial sales since the outset of the pandemic. The degree to which the COVID-19 pandemic may impact Alliant Energy, IPL and WPL in the future is currently unknown and will depend on future developments of the pandemic as well as possible additional actions by government and regulatory authorities.

A change in management’s estimates or assumptions could have a material impact on financial condition and results of operations during the period in which such change occurred. Certain prior period amounts in the Financial Statements and Notes have been reclassified to conform to the current period presentation for comparative purposes.

NOTE 1(b) Cash and Cash Equivalents - At June 30, 2020, Alliant Energy’s and IPL’s cash and cash equivalents included $198.3 million and $198.3 million of money market fund investments, with weighted average interest rates of 0.1% and 0.1%, respectively.

NOTE 1(c) Current Expected Credit Losses Estimates - Current expected credit losses are estimated for trade and other receivables and credit exposures on guarantees of the performance by third parties. The current expected credit losses for short-term trade receivables are based on estimates of losses resulting from the inability of customers to make required payments. The methodology used to estimate losses is based on historical write-offs, regional economic conditions, significant events that could impact collectability, such as impacts related to COVID-19 and related regulatory actions, and forecasted changes to the accounts receivable aging portfolio and write-offs. The current expected credit losses related to guarantees of the performance by third parties are estimated using both quantitative and qualitative information, which utilizes potential outcomes in a range of possible estimated amounts.

NOTE 1(d) New Accounting Standards -

Credit Losses - In June 2016, the Financial Accounting Standards Board issued an accounting standard requiring use of a current expected credit loss model rather than an incurred loss method, which is intended to result in more timely recognition of credit losses on trade receivables, certain other assets and off-balance sheet credit exposures. Alliant Energy, IPL and WPL adopted this standard on January 1, 2020 using a modified retrospective method of adoption, which required cumulative effect adjustments to retained earnings on January 1, 2020. IPL and WPL did not record a cumulative effect adjustment to retained earnings and Alliant Energy recorded a pre-tax $12 million (after-tax $8.7 million) cumulative effect adjustment to decrease retained earnings related to Alliant Energy’s guarantees in the partnership obligations of an affiliate of Whiting Petroleum (refer to Note 13(c) for further discussion). This adjustment is included in “Adoption of new accounting standard” in Alliant Energy’s summary of changes in shareowners’ equity in Note 5 for the six months ended June 30, 2020.

XML

Regulatory Matters

6 Months Ended

Jun. 30, 2020

Public Utilities, General Disclosures [Line Items]

Regulatory Matters

REGULATORY MATTERS

Regulatory Assets and Regulatory Liabilities -

Regulatory assets were comprised of the following items (in millions):

	Alliant Energy				IPL				WPL
	June 30, 2020		December 31, 2019		June 30, 2020		December 31, 2019		June 30, 2020		December 31, 2019
Tax-related		$842.5		$817.6		$797.4		$776.8		$45.1		$40.8
Pension and OPEB costs	501.2		524.0		251.3		262.5		249.9		261.5
Assets retired early	122.9		134.0		81.8		87.9		41.1		46.1
Asset retirement obligations	114.0		111.8		78.2		76.2		35.8		35.6
IPL’s DAEC PPA amendment	109.4		108.2		109.4		108.2		—		—
Derivatives	47.0		39.5		20.5		18.3		26.5		21.2
Emission allowances	19.8		21.1		19.8		21.1		—		—
Other	86.2		88.5		46.5		48.3		39.7		40.2
		$1,843.0		$1,844.7		$1,404.9		$1,399.3		$438.1		$445.4

Regulatory liabilities were comprised of the following items (in millions):

	Alliant Energy				IPL				WPL
	June 30, 2020		December 31, 2019		June 30, 2020		December 31, 2019		June 30, 2020		December 31, 2019
Tax-related		$779.0		$835.6		$343.6		$350.9		$435.4		$484.7
Cost of removal obligations	385.8		387.7		256.4		257.0		129.4		130.7
Electric transmission cost recovery	66.3		88.6		30.7		51.3		35.6		37.3
Commodity cost recovery	30.1		24.2		14.0		8.8		16.1		15.4
Derivatives	28.8		19.9		26.3		17.4		2.5		2.5
WPL’s earnings sharing mechanism	20.4		21.9		—		—		20.4		21.9
Other	60.6		45.7		46.9		29.3		13.7		16.4
		$1,371.0		$1,423.6		$717.9		$714.7		$653.1		$708.9

Tax-related - Alliant Energy’s, IPL’s and WPL’s tax-related regulatory liabilities are primarily related to excess deferred tax benefits resulting from the remeasurement of accumulated deferred income taxes caused by Federal Tax Reform. During the six months ended June 30, 2020, Alliant Energy’s, IPL’s and WPL’s tax-related regulatory liabilities decreased primarily from returning a portion of these excess deferred tax benefits back to customers.

Electric transmission cost recovery - In the second quarter of 2020, pursuant to a June 2020 IUB order, IPL issued $42 million of credits to its retail electric customers through its transmission cost rider for amounts previously collected in rates, which resulted in a corresponding reduction to “Electric transmission service” expense in Alliant Energy’s and IPL’s income statements for the three and six months ended June 30, 2020.

Refer to Note 13(f) for discussion of refunds received by IPL and WPL in the second quarter of 2020 related to MISO transmission owner return on equity complaints.

IPL [Member]

Public Utilities, General Disclosures [Line Items]

Regulatory Matters

REGULATORY MATTERS

Regulatory Assets and Regulatory Liabilities -

Regulatory assets were comprised of the following items (in millions):

	Alliant Energy				IPL				WPL
	June 30, 2020		December 31, 2019		June 30, 2020		December 31, 2019		June 30, 2020		December 31, 2019
Tax-related		$842.5		$817.6		$797.4		$776.8		$45.1		$40.8
Pension and OPEB costs	501.2		524.0		251.3		262.5		249.9		261.5
Assets retired early	122.9		134.0		81.8		87.9		41.1		46.1
Asset retirement obligations	114.0		111.8		78.2		76.2		35.8		35.6
IPL’s DAEC PPA amendment	109.4		108.2		109.4		108.2		—		—
Derivatives	47.0		39.5		20.5		18.3		26.5		21.2
Emission allowances	19.8		21.1		19.8		21.1		—		—
Other	86.2		88.5		46.5		48.3		39.7		40.2
		$1,843.0		$1,844.7		$1,404.9		$1,399.3		$438.1		$445.4

Regulatory liabilities were comprised of the following items (in millions):

	Alliant Energy				IPL				WPL
	June 30, 2020		December 31, 2019		June 30, 2020		December 31, 2019		June 30, 2020		December 31, 2019
Tax-related		$779.0		$835.6		$343.6		$350.9		$435.4		$484.7
Cost of removal obligations	385.8		387.7		256.4		257.0		129.4		130.7
Electric transmission cost recovery	66.3		88.6		30.7		51.3		35.6		37.3
Commodity cost recovery	30.1		24.2		14.0		8.8		16.1		15.4
Derivatives	28.8		19.9		26.3		17.4		2.5		2.5
WPL’s earnings sharing mechanism	20.4		21.9		—		—		20.4		21.9
Other	60.6		45.7		46.9		29.3		13.7		16.4
		$1,371.0		$1,423.6		$717.9		$714.7		$653.1		$708.9

Tax-related - Alliant Energy’s, IPL’s and WPL’s tax-related regulatory liabilities are primarily related to excess deferred tax benefits resulting from the remeasurement of accumulated deferred income taxes caused by Federal Tax Reform. During the six months ended June 30, 2020, Alliant Energy’s, IPL’s and WPL’s tax-related regulatory liabilities decreased primarily from returning a portion of these excess deferred tax benefits back to customers.

Electric transmission cost recovery - In the second quarter of 2020, pursuant to a June 2020 IUB order, IPL issued $42 million of credits to its retail electric customers through its transmission cost rider for amounts previously collected in rates, which resulted in a corresponding reduction to “Electric transmission service” expense in Alliant Energy’s and IPL’s income statements for the three and six months ended June 30, 2020.

Refer to Note 13(f) for discussion of refunds received by IPL and WPL in the second quarter of 2020 related to MISO transmission owner return on equity complaints.

WPL [Member]

Public Utilities, General Disclosures [Line Items]

Regulatory Matters

REGULATORY MATTERS

Regulatory Assets and Regulatory Liabilities -

Regulatory assets were comprised of the following items (in millions):

	Alliant Energy				IPL				WPL
	June 30, 2020		December 31, 2019		June 30, 2020		December 31, 2019		June 30, 2020		December 31, 2019
Tax-related		$842.5		$817.6		$797.4		$776.8		$45.1		$40.8
Pension and OPEB costs	501.2		524.0		251.3		262.5		249.9		261.5
Assets retired early	122.9		134.0		81.8		87.9		41.1		46.1
Asset retirement obligations	114.0		111.8		78.2		76.2		35.8		35.6
IPL’s DAEC PPA amendment	109.4		108.2		109.4		108.2		—		—
Derivatives	47.0		39.5		20.5		18.3		26.5		21.2
Emission allowances	19.8		21.1		19.8		21.1		—		—
Other	86.2		88.5		46.5		48.3		39.7		40.2
		$1,843.0		$1,844.7		$1,404.9		$1,399.3		$438.1		$445.4

Regulatory liabilities were comprised of the following items (in millions):

	Alliant Energy				IPL				WPL
	June 30, 2020		December 31, 2019		June 30, 2020		December 31, 2019		June 30, 2020		December 31, 2019
Tax-related		$779.0		$835.6		$343.6		$350.9		$435.4		$484.7
Cost of removal obligations	385.8		387.7		256.4		257.0		129.4		130.7
Electric transmission cost recovery	66.3		88.6		30.7		51.3		35.6		37.3
Commodity cost recovery	30.1		24.2		14.0		8.8		16.1		15.4
Derivatives	28.8		19.9		26.3		17.4		2.5		2.5
WPL’s earnings sharing mechanism	20.4		21.9		—		—		20.4		21.9
Other	60.6		45.7		46.9		29.3		13.7		16.4
		$1,371.0		$1,423.6		$717.9		$714.7		$653.1		$708.9

Tax-related - Alliant Energy’s, IPL’s and WPL’s tax-related regulatory liabilities are primarily related to excess deferred tax benefits resulting from the remeasurement of accumulated deferred income taxes caused by Federal Tax Reform. During the six months ended June 30, 2020, Alliant Energy’s, IPL’s and WPL’s tax-related regulatory liabilities decreased primarily from returning a portion of these excess deferred tax benefits back to customers.

Electric transmission cost recovery - In the second quarter of 2020, pursuant to a June 2020 IUB order, IPL issued $42 million of credits to its retail electric customers through its transmission cost rider for amounts previously collected in rates, which resulted in a corresponding reduction to “Electric transmission service” expense in Alliant Energy’s and IPL’s income statements for the three and six months ended June 30, 2020.

Refer to Note 13(f) for discussion of refunds received by IPL and WPL in the second quarter of 2020 related to MISO transmission owner return on equity complaints.

XML

Receivables

6 Months Ended

Jun. 30, 2020

Receivables [Line Items]

Receivables

RECEIVABLES

Note 3(a) Accounts Receivable - Details for accounts receivable included on the balance sheets were as follows (in millions):

	Alliant Energy						IPL						WPL
	June 30, 2020			December 31, 2019			June 30, 2020			December 31, 2019			June 30, 2020			December 31, 2019
Customer		$92.7			$91.6			$—			$—			$82.4			$83.5
Unbilled utility revenues	68.2			82.1			—			—			68.2			82.1
Deferred proceeds	194.1			187.7			194.1			187.7			—			—
Other	41.5			48.0			16.5			16.3			24.5			31.4
Allowance for expected credit losses	(10.0		)	(7.3		)	(1.7		)	(1.2		)	(8.2		)	(6.1		)
		$386.5			$402.1			$208.9			$202.8			$166.9			$190.9

Note 3(b) Sales of Accounts Receivable - IPL maintains a Receivables Purchase and Sale Agreement (Receivables Agreement) whereby it may sell its customer accounts receivables, unbilled revenues and certain other accounts receivables to a third party through wholly-owned and consolidated special purpose entities. The transfers of receivables meet the criteria for sale accounting established by the transfer of financial assets accounting rules. As of June 30, 2020, IPL had $89 million of available capacity under its sales of accounts receivable program. IPL’s maximum and average outstanding cash proceeds (based on daily outstanding balances) related to the sales of accounts receivable program for the three and six months ended June 30 were as follows (in millions):

	Three Months				Six Months
	2020		2019		2020		2019
Maximum outstanding aggregate cash proceeds		$65.0		$25.0		$96.0		$108.0
Average outstanding aggregate cash proceeds	11.1		2.6		17.3		41.6

The attributes of IPL’s receivables sold under the Receivables Agreement were as follows (in millions):

	June 30, 2020		December 31, 2019
Customer accounts receivable		$113.5		$124.7
Unbilled utility revenues	92.3		95.5
Other receivables	0.4		0.9
Receivables sold to third party	206.2		221.1
Less: cash proceeds	1.0		27.0
Deferred proceeds	205.2		194.1
Less: allowance for expected credit losses	11.1		6.4
Fair value of deferred proceeds		$194.1		$187.7

As of June 30, 2020, outstanding receivables past due under the Receivables Agreement were $25.1 million. Additional attributes of IPL’s receivables sold under the Receivables Agreement for the three and six months ended June 30 were as follows (in millions):

	Three Months				Six Months
	2020		2019		2020		2019
Collections		$453.0		$487.7		$994.4		$1,043.5
Write-offs, net of recoveries	1.2		2.6		3.3		8.1

IPL [Member]

Receivables [Line Items]

Receivables

RECEIVABLES

Note 3(a) Accounts Receivable - Details for accounts receivable included on the balance sheets were as follows (in millions):

	Alliant Energy						IPL						WPL
	June 30, 2020			December 31, 2019			June 30, 2020			December 31, 2019			June 30, 2020			December 31, 2019
Customer		$92.7			$91.6			$—			$—			$82.4			$83.5
Unbilled utility revenues	68.2			82.1			—			—			68.2			82.1
Deferred proceeds	194.1			187.7			194.1			187.7			—			—
Other	41.5			48.0			16.5			16.3			24.5			31.4
Allowance for expected credit losses	(10.0		)	(7.3		)	(1.7		)	(1.2		)	(8.2		)	(6.1		)
		$386.5			$402.1			$208.9			$202.8			$166.9			$190.9

Note 3(b) Sales of Accounts Receivable - IPL maintains a Receivables Purchase and Sale Agreement (Receivables Agreement) whereby it may sell its customer accounts receivables, unbilled revenues and certain other accounts receivables to a third party through wholly-owned and consolidated special purpose entities. The transfers of receivables meet the criteria for sale accounting established by the transfer of financial assets accounting rules. As of June 30, 2020, IPL had $89 million of available capacity under its sales of accounts receivable program. IPL’s maximum and average outstanding cash proceeds (based on daily outstanding balances) related to the sales of accounts receivable program for the three and six months ended June 30 were as follows (in millions):

	Three Months				Six Months
	2020		2019		2020		2019
Maximum outstanding aggregate cash proceeds		$65.0		$25.0		$96.0		$108.0
Average outstanding aggregate cash proceeds	11.1		2.6		17.3		41.6

The attributes of IPL’s receivables sold under the Receivables Agreement were as follows (in millions):

	June 30, 2020		December 31, 2019
Customer accounts receivable		$113.5		$124.7
Unbilled utility revenues	92.3		95.5
Other receivables	0.4		0.9
Receivables sold to third party	206.2		221.1
Less: cash proceeds	1.0		27.0
Deferred proceeds	205.2		194.1
Less: allowance for expected credit losses	11.1		6.4
Fair value of deferred proceeds		$194.1		$187.7

As of June 30, 2020, outstanding receivables past due under the Receivables Agreement were $25.1 million. Additional attributes of IPL’s receivables sold under the Receivables Agreement for the three and six months ended June 30 were as follows (in millions):

	Three Months				Six Months
	2020		2019		2020		2019
Collections		$453.0		$487.7		$994.4		$1,043.5
Write-offs, net of recoveries	1.2		2.6		3.3		8.1

WPL [Member]

Receivables [Line Items]

Receivables

RECEIVABLES

Note 3(a) Accounts Receivable - Details for accounts receivable included on the balance sheets were as follows (in millions):

	Alliant Energy						IPL						WPL
	June 30, 2020			December 31, 2019			June 30, 2020			December 31, 2019			June 30, 2020			December 31, 2019
Customer		$92.7			$91.6			$—			$—			$82.4			$83.5
Unbilled utility revenues	68.2			82.1			—			—			68.2			82.1
Deferred proceeds	194.1			187.7			194.1			187.7			—			—
Other	41.5			48.0			16.5			16.3			24.5			31.4
Allowance for expected credit losses	(10.0		)	(7.3		)	(1.7		)	(1.2		)	(8.2		)	(6.1		)
		$386.5			$402.1			$208.9			$202.8			$166.9			$190.9

XML

Investments

6 Months Ended

Jun. 30, 2020

Schedule of Equity Method Investments [Line Items]

Investments

INVESTMENTS

Unconsolidated Equity Investments - Alliant Energy’s equity (income) loss from unconsolidated investments accounted for under the equity method of accounting for the three and six months ended June 30 was as follows (in millions):

	Three Months						Six Months
	2020			2019			2020			2019
ATC Holdings		($13.5	)		($10.0	)		($24.5	)		($19.5	)
Non-utility wind farm in Oklahoma	(1.9		)	(1.3		)	(4.1		)	(2.4		)
Other	(2.0		)	(1.4		)	(2.2		)	(1.7		)
		($17.4	)		($12.7	)		($30.8	)		($23.6	)

XML

Common Equity

6 Months Ended

Jun. 30, 2020

Common Equity [Line Items]

Common Equity

COMMON EQUITY

Common Share Activity - A summary of Alliant Energy’s common stock activity was as follows:

Shares outstanding, January 1, 2020	245,022,800
Equity forward agreements	4,275,127
Shareowner Direct Plan	248,220
Equity-based compensation plans	98,205
Shares outstanding, June 30, 2020	249,644,352

Equity Forward Agreements - In November 2019, Alliant Energy entered into forward sale agreements with a counterparty in connection with a public offering of 4,275,127 shares of Alliant Energy common stock. The initial forward sale price of $52.235 per share was subject to daily adjustment based on a floating interest rate factor, and decreased by other fixed amounts specified in the forward sale agreements. In the first quarter of 2020, Alliant Energy settled $222 million under the forward sale agreements by delivering 4,275,127 shares of newly issued Alliant Energy common stock at a weighted average forward sale price of $51.98 per share. Alliant Energy used the net proceeds from the settlements for general corporate purposes.

Changes in Shareowners’ Equity - A summary of changes in shareowners’ equity was as follows (in millions):

Alliant Energy	Total Alliant Energy Common Equity
								Accumulated			Shares in			Cumulative
			Additional					Other			Deferred			Preferred
	Common		Paid-In		Retained			Comprehensive			Compensation			Stock		Total
	Stock		Capital		Earnings			Income (Loss)			Trust			of IPL		Equity
Three Months Ended June 30, 2020
Beginning balance, March 31, 2020		$2.5		$2,674.1		$2,833.7			$2.0			($9.9	)		$200.0		$5,702.4
Net income attributable to Alliant Energy common shareowners					134.4											134.4
Common stock dividends ($0.38 per share)					(94.6		)									(94.6		)
Shareowner Direct Plan issuances			6.4													6.4
Equity-based compensation plans and other			2.6								(0.3		)			2.3
Other comprehensive loss, net of tax								(2.6		)						(2.6		)
Ending balance, June 30, 2020		$2.5		$2,683.1		$2,873.5			($0.6	)		($10.2	)		$200.0		$5,748.3
Three Months Ended June 30, 2019
Beginning balance, March 31, 2019		$2.4		$2,100.0		$2,587.3			$2.4			($9.7	)		$200.0		$4,882.4
Net income attributable to Alliant Energy common shareowners					94.6											94.6
Common stock dividends ($0.355 per share)					(84.1		)									(84.1		)
Shareowner Direct Plan issuances			6.0													6.0
Equity-based compensation plans and other			2.4								(0.3		)			2.1
Other comprehensive loss, net of tax								(1.4		)						(1.4		)
Ending balance, June 30, 2019		$2.4		$2,108.4		$2,597.8			$1.0			($10.0	)		$200.0		$4,899.6

Alliant Energy	Total Alliant Energy Common Equity
								Accumulated			Shares in			Cumulative
			Additional					Other			Deferred			Preferred
	Common		Paid-In		Retained			Comprehensive			Compensation			Stock		Total
	Stock		Capital		Earnings			Income (Loss)			Trust			of IPL		Equity
Six Months Ended June 30, 2020
Beginning balance, December 31, 2019		$2.5		$2,445.9		$2,765.4			$1.3			($10.0	)		$200.0		$5,405.1
Net income attributable to Alliant Energy common shareowners					304.4											304.4
Common stock dividends ($0.76 per share)					(187.6		)									(187.6		)
Equity forward settlements and Shareowner Direct Plan issuances			234.8													234.8
Equity-based compensation plans and other			2.4								(0.2		)			2.2
Adoption of new accounting standard, net of tax (refer to Note 1(d))					(8.7		)									(8.7		)
Other comprehensive loss, net of tax								(1.9		)						(1.9		)
Ending balance, June 30, 2020		$2.5		$2,683.1		$2,873.5			($0.6	)		($10.2	)		$200.0		$5,748.3
Six Months Ended June 30, 2019
Beginning balance, December 31, 2018		$2.4		$2,045.5		$2,545.9			$1.7			($9.8	)		$200.0		$4,785.7
Net income attributable to Alliant Energy common shareowners					219.7											219.7
Common stock dividends ($0.71 per share)					(167.8		)									(167.8		)
Equity forward settlements and Shareowner Direct Plan issuances			60.6													60.6
Equity-based compensation plans and other			2.3								(0.2		)			2.1
Other comprehensive loss, net of tax								(0.7		)						(0.7		)
Ending balance, June 30, 2019		$2.4		$2,108.4		$2,597.8			$1.0			($10.0	)		$200.0		$4,899.6

IPL	Total IPL Common Equity
			Additional					Cumulative
	Common		Paid-In		Retained			Preferred		Total
	Stock		Capital		Earnings			Stock		Equity
Three Months Ended June 30, 2020
Beginning balance, March 31, 2020		$33.4		$2,447.8		$914.2			$200.0		$3,595.4
Net income available for common stock					59.8					59.8
Common stock dividends					(59.1		)			(59.1		)
Capital contributions from parent			75.0							75.0
Ending balance, June 30, 2020		$33.4		$2,522.8		$914.9			$200.0		$3,671.1
Three Months Ended June 30, 2019
Beginning balance, March 31, 2019		$33.4		$2,322.8		$785.8			$200.0		$3,342.0
Net income available for common stock					45.0					45.0
Common stock dividends					(41.9		)			(41.9		)
Ending balance, June 30, 2019		$33.4		$2,322.8		$788.9			$200.0		$3,345.1

IPL	Total IPL Common Equity
			Additional					Cumulative
	Common		Paid-In		Retained			Preferred		Total
	Stock		Capital		Earnings			Stock		Equity
Six Months Ended June 30, 2020
Beginning balance, December 31, 2019		$33.4		$2,347.8		$890.6			$200.0		$3,471.8
Net income available for common stock					142.4					142.4
Common stock dividends					(118.1		)			(118.1		)
Capital contributions from parent			175.0							175.0
Ending balance, June 30, 2020		$33.4		$2,522.8		$914.9			$200.0		$3,671.1
Six Months Ended June 30, 2019
Beginning balance, December 31, 2018		$33.4		$2,222.8		$774.5			$200.0		$3,230.7
Net income available for common stock					98.3					98.3
Common stock dividends					(83.9		)			(83.9		)
Capital contributions from parent			100.0							100.0
Ending balance, June 30, 2019		$33.4		$2,322.8		$788.9			$200.0		$3,345.1

WPL			Additional					Total
	Common		Paid-In		Retained			Common
	Stock		Capital		Earnings			Equity
Three Months Ended June 30, 2020
Beginning balance, March 31, 2020		$66.2		$1,459.0		$910.9			$2,436.1
Net income					57.6			57.6
Common stock dividends					(41.9		)	(41.9		)
Ending balance, June 30, 2020		$66.2		$1,459.0		$926.6			$2,451.8
Three Months Ended June 30, 2019
Beginning balance, March 31, 2019		$66.2		$1,309.0		$804.0			$2,179.2
Net income					42.0			42.0
Common stock dividends					(36.0		)	(36.0		)
Ending balance, June 30, 2019		$66.2		$1,309.0		$810.0			$2,185.2

WPL			Additional					Total
	Common		Paid-In		Retained			Common
	Stock		Capital		Earnings			Equity
Six Months Ended June 30, 2020
Beginning balance, December 31, 2019		$66.2		$1,434.0		$863.4			$2,363.6
Net income					147.2			147.2
Common stock dividends					(84.0		)	(84.0		)
Capital contributions from parent			25.0					25.0
Ending balance, June 30, 2020		$66.2		$1,459.0		$926.6			$2,451.8
Six Months Ended June 30, 2019
Beginning balance, December 31, 2018		$66.2		$1,309.0		$774.3			$2,149.5
Net income					107.7			107.7
Common stock dividends					(72.0		)	(72.0		)
Ending balance, June 30, 2019		$66.2		$1,309.0		$810.0			$2,185.2

IPL [Member]

Common Equity [Line Items]

Common Equity

COMMON EQUITY

Common Share Activity - A summary of Alliant Energy’s common stock activity was as follows:

Shares outstanding, January 1, 2020	245,022,800
Equity forward agreements	4,275,127
Shareowner Direct Plan	248,220
Equity-based compensation plans	98,205
Shares outstanding, June 30, 2020	249,644,352

Equity Forward Agreements - In November 2019, Alliant Energy entered into forward sale agreements with a counterparty in connection with a public offering of 4,275,127 shares of Alliant Energy common stock. The initial forward sale price of $52.235 per share was subject to daily adjustment based on a floating interest rate factor, and decreased by other fixed amounts specified in the forward sale agreements. In the first quarter of 2020, Alliant Energy settled $222 million under the forward sale agreements by delivering 4,275,127 shares of newly issued Alliant Energy common stock at a weighted average forward sale price of $51.98 per share. Alliant Energy used the net proceeds from the settlements for general corporate purposes.

Changes in Shareowners’ Equity - A summary of changes in shareowners’ equity was as follows (in millions):

Alliant Energy	Total Alliant Energy Common Equity
								Accumulated			Shares in			Cumulative
			Additional					Other			Deferred			Preferred
	Common		Paid-In		Retained			Comprehensive			Compensation			Stock		Total
	Stock		Capital		Earnings			Income (Loss)			Trust			of IPL		Equity
Three Months Ended June 30, 2020
Beginning balance, March 31, 2020		$2.5		$2,674.1		$2,833.7			$2.0			($9.9	)		$200.0		$5,702.4
Net income attributable to Alliant Energy common shareowners					134.4											134.4
Common stock dividends ($0.38 per share)					(94.6		)									(94.6		)
Shareowner Direct Plan issuances			6.4													6.4
Equity-based compensation plans and other			2.6								(0.3		)			2.3
Other comprehensive loss, net of tax								(2.6		)						(2.6		)
Ending balance, June 30, 2020		$2.5		$2,683.1		$2,873.5			($0.6	)		($10.2	)		$200.0		$5,748.3
Three Months Ended June 30, 2019
Beginning balance, March 31, 2019		$2.4		$2,100.0		$2,587.3			$2.4			($9.7	)		$200.0		$4,882.4
Net income attributable to Alliant Energy common shareowners					94.6											94.6
Common stock dividends ($0.355 per share)					(84.1		)									(84.1		)
Shareowner Direct Plan issuances			6.0													6.0
Equity-based compensation plans and other			2.4								(0.3		)			2.1
Other comprehensive loss, net of tax								(1.4		)						(1.4		)
Ending balance, June 30, 2019		$2.4		$2,108.4		$2,597.8			$1.0			($10.0	)		$200.0		$4,899.6

Alliant Energy	Total Alliant Energy Common Equity
								Accumulated			Shares in			Cumulative
			Additional					Other			Deferred			Preferred
	Common		Paid-In		Retained			Comprehensive			Compensation			Stock		Total
	Stock		Capital		Earnings			Income (Loss)			Trust			of IPL		Equity
Six Months Ended June 30, 2020
Beginning balance, December 31, 2019		$2.5		$2,445.9		$2,765.4			$1.3			($10.0	)		$200.0		$5,405.1
Net income attributable to Alliant Energy common shareowners					304.4											304.4
Common stock dividends ($0.76 per share)					(187.6		)									(187.6		)
Equity forward settlements and Shareowner Direct Plan issuances			234.8													234.8
Equity-based compensation plans and other			2.4								(0.2		)			2.2
Adoption of new accounting standard, net of tax (refer to Note 1(d))					(8.7		)									(8.7		)
Other comprehensive loss, net of tax								(1.9		)						(1.9		)
Ending balance, June 30, 2020		$2.5		$2,683.1		$2,873.5			($0.6	)		($10.2	)		$200.0		$5,748.3
Six Months Ended June 30, 2019
Beginning balance, December 31, 2018		$2.4		$2,045.5		$2,545.9			$1.7			($9.8	)		$200.0		$4,785.7
Net income attributable to Alliant Energy common shareowners					219.7											219.7
Common stock dividends ($0.71 per share)					(167.8		)									(167.8		)
Equity forward settlements and Shareowner Direct Plan issuances			60.6													60.6
Equity-based compensation plans and other			2.3								(0.2		)			2.1
Other comprehensive loss, net of tax								(0.7		)						(0.7		)
Ending balance, June 30, 2019		$2.4		$2,108.4		$2,597.8			$1.0			($10.0	)		$200.0		$4,899.6

IPL	Total IPL Common Equity
			Additional					Cumulative
	Common		Paid-In		Retained			Preferred		Total
	Stock		Capital		Earnings			Stock		Equity
Three Months Ended June 30, 2020
Beginning balance, March 31, 2020		$33.4		$2,447.8		$914.2			$200.0		$3,595.4
Net income available for common stock					59.8					59.8
Common stock dividends					(59.1		)			(59.1		)
Capital contributions from parent			75.0							75.0
Ending balance, June 30, 2020		$33.4		$2,522.8		$914.9			$200.0		$3,671.1
Three Months Ended June 30, 2019
Beginning balance, March 31, 2019		$33.4		$2,322.8		$785.8			$200.0		$3,342.0
Net income available for common stock					45.0					45.0
Common stock dividends					(41.9		)			(41.9		)
Ending balance, June 30, 2019		$33.4		$2,322.8		$788.9			$200.0		$3,345.1

IPL	Total IPL Common Equity
			Additional					Cumulative
	Common		Paid-In		Retained			Preferred		Total
	Stock		Capital		Earnings			Stock		Equity
Six Months Ended June 30, 2020
Beginning balance, December 31, 2019		$33.4		$2,347.8		$890.6			$200.0		$3,471.8
Net income available for common stock					142.4					142.4
Common stock dividends					(118.1		)			(118.1		)
Capital contributions from parent			175.0							175.0
Ending balance, June 30, 2020		$33.4		$2,522.8		$914.9			$200.0		$3,671.1
Six Months Ended June 30, 2019
Beginning balance, December 31, 2018		$33.4		$2,222.8		$774.5			$200.0		$3,230.7
Net income available for common stock					98.3					98.3
Common stock dividends					(83.9		)			(83.9		)
Capital contributions from parent			100.0							100.0
Ending balance, June 30, 2019		$33.4		$2,322.8		$788.9			$200.0		$3,345.1

WPL			Additional					Total
	Common		Paid-In		Retained			Common
	Stock		Capital		Earnings			Equity
Three Months Ended June 30, 2020
Beginning balance, March 31, 2020		$66.2		$1,459.0		$910.9			$2,436.1
Net income					57.6			57.6
Common stock dividends					(41.9		)	(41.9		)
Ending balance, June 30, 2020		$66.2		$1,459.0		$926.6			$2,451.8
Three Months Ended June 30, 2019
Beginning balance, March 31, 2019		$66.2		$1,309.0		$804.0			$2,179.2
Net income					42.0			42.0
Common stock dividends					(36.0		)	(36.0		)
Ending balance, June 30, 2019		$66.2		$1,309.0		$810.0			$2,185.2

WPL			Additional					Total
	Common		Paid-In		Retained			Common
	Stock		Capital		Earnings			Equity
Six Months Ended June 30, 2020
Beginning balance, December 31, 2019		$66.2		$1,434.0		$863.4			$2,363.6
Net income					147.2			147.2
Common stock dividends					(84.0		)	(84.0		)
Capital contributions from parent			25.0					25.0
Ending balance, June 30, 2020		$66.2		$1,459.0		$926.6			$2,451.8
Six Months Ended June 30, 2019
Beginning balance, December 31, 2018		$66.2		$1,309.0		$774.3			$2,149.5
Net income					107.7			107.7
Common stock dividends					(72.0		)	(72.0		)
Ending balance, June 30, 2019		$66.2		$1,309.0		$810.0			$2,185.2

WPL [Member]

Common Equity [Line Items]

Common Equity

COMMON EQUITY

Common Share Activity - A summary of Alliant Energy’s common stock activity was as follows:

Shares outstanding, January 1, 2020	245,022,800
Equity forward agreements	4,275,127
Shareowner Direct Plan	248,220
Equity-based compensation plans	98,205
Shares outstanding, June 30, 2020	249,644,352

Equity Forward Agreements - In November 2019, Alliant Energy entered into forward sale agreements with a counterparty in connection with a public offering of 4,275,127 shares of Alliant Energy common stock. The initial forward sale price of $52.235 per share was subject to daily adjustment based on a floating interest rate factor, and decreased by other fixed amounts specified in the forward sale agreements. In the first quarter of 2020, Alliant Energy settled $222 million under the forward sale agreements by delivering 4,275,127 shares of newly issued Alliant Energy common stock at a weighted average forward sale price of $51.98 per share. Alliant Energy used the net proceeds from the settlements for general corporate purposes.

Changes in Shareowners’ Equity - A summary of changes in shareowners’ equity was as follows (in millions):

Alliant Energy	Total Alliant Energy Common Equity
								Accumulated			Shares in			Cumulative
			Additional					Other			Deferred			Preferred
	Common		Paid-In		Retained			Comprehensive			Compensation			Stock		Total
	Stock		Capital		Earnings			Income (Loss)			Trust			of IPL		Equity
Three Months Ended June 30, 2020
Beginning balance, March 31, 2020		$2.5		$2,674.1		$2,833.7			$2.0			($9.9	)		$200.0		$5,702.4
Net income attributable to Alliant Energy common shareowners					134.4											134.4
Common stock dividends ($0.38 per share)					(94.6		)									(94.6		)
Shareowner Direct Plan issuances			6.4													6.4
Equity-based compensation plans and other			2.6								(0.3		)			2.3
Other comprehensive loss, net of tax								(2.6		)						(2.6		)
Ending balance, June 30, 2020		$2.5		$2,683.1		$2,873.5			($0.6	)		($10.2	)		$200.0		$5,748.3
Three Months Ended June 30, 2019
Beginning balance, March 31, 2019		$2.4		$2,100.0		$2,587.3			$2.4			($9.7	)		$200.0		$4,882.4
Net income attributable to Alliant Energy common shareowners					94.6											94.6
Common stock dividends ($0.355 per share)					(84.1		)									(84.1		)
Shareowner Direct Plan issuances			6.0													6.0
Equity-based compensation plans and other			2.4								(0.3		)			2.1
Other comprehensive loss, net of tax								(1.4		)						(1.4		)
Ending balance, June 30, 2019		$2.4		$2,108.4		$2,597.8			$1.0			($10.0	)		$200.0		$4,899.6

Alliant Energy	Total Alliant Energy Common Equity
								Accumulated			Shares in			Cumulative
			Additional					Other			Deferred			Preferred
	Common		Paid-In		Retained			Comprehensive			Compensation			Stock		Total
	Stock		Capital		Earnings			Income (Loss)			Trust			of IPL		Equity
Six Months Ended June 30, 2020
Beginning balance, December 31, 2019		$2.5		$2,445.9		$2,765.4			$1.3			($10.0	)		$200.0		$5,405.1
Net income attributable to Alliant Energy common shareowners					304.4											304.4
Common stock dividends ($0.76 per share)					(187.6		)									(187.6		)
Equity forward settlements and Shareowner Direct Plan issuances			234.8													234.8
Equity-based compensation plans and other			2.4								(0.2		)			2.2
Adoption of new accounting standard, net of tax (refer to Note 1(d))					(8.7		)									(8.7		)
Other comprehensive loss, net of tax								(1.9		)						(1.9		)
Ending balance, June 30, 2020		$2.5		$2,683.1		$2,873.5			($0.6	)		($10.2	)		$200.0		$5,748.3
Six Months Ended June 30, 2019
Beginning balance, December 31, 2018		$2.4		$2,045.5		$2,545.9			$1.7			($9.8	)		$200.0		$4,785.7
Net income attributable to Alliant Energy common shareowners					219.7											219.7
Common stock dividends ($0.71 per share)					(167.8		)									(167.8		)
Equity forward settlements and Shareowner Direct Plan issuances			60.6													60.6
Equity-based compensation plans and other			2.3								(0.2		)			2.1
Other comprehensive loss, net of tax								(0.7		)						(0.7		)
Ending balance, June 30, 2019		$2.4		$2,108.4		$2,597.8			$1.0			($10.0	)		$200.0		$4,899.6

IPL	Total IPL Common Equity
			Additional					Cumulative
	Common		Paid-In		Retained			Preferred		Total
	Stock		Capital		Earnings			Stock		Equity
Three Months Ended June 30, 2020
Beginning balance, March 31, 2020		$33.4		$2,447.8		$914.2			$200.0		$3,595.4
Net income available for common stock					59.8					59.8
Common stock dividends					(59.1		)			(59.1		)
Capital contributions from parent			75.0							75.0
Ending balance, June 30, 2020		$33.4		$2,522.8		$914.9			$200.0		$3,671.1
Three Months Ended June 30, 2019
Beginning balance, March 31, 2019		$33.4		$2,322.8		$785.8			$200.0		$3,342.0
Net income available for common stock					45.0					45.0
Common stock dividends					(41.9		)			(41.9		)
Ending balance, June 30, 2019		$33.4		$2,322.8		$788.9			$200.0		$3,345.1

IPL	Total IPL Common Equity
			Additional					Cumulative
	Common		Paid-In		Retained			Preferred		Total
	Stock		Capital		Earnings			Stock		Equity
Six Months Ended June 30, 2020
Beginning balance, December 31, 2019		$33.4		$2,347.8		$890.6			$200.0		$3,471.8
Net income available for common stock					142.4					142.4
Common stock dividends					(118.1		)			(118.1		)
Capital contributions from parent			175.0							175.0
Ending balance, June 30, 2020		$33.4		$2,522.8		$914.9			$200.0		$3,671.1
Six Months Ended June 30, 2019
Beginning balance, December 31, 2018		$33.4		$2,222.8		$774.5			$200.0		$3,230.7
Net income available for common stock					98.3					98.3
Common stock dividends					(83.9		)			(83.9		)
Capital contributions from parent			100.0							100.0
Ending balance, June 30, 2019		$33.4		$2,322.8		$788.9			$200.0		$3,345.1

WPL			Additional					Total
	Common		Paid-In		Retained			Common
	Stock		Capital		Earnings			Equity
Three Months Ended June 30, 2020
Beginning balance, March 31, 2020		$66.2		$1,459.0		$910.9			$2,436.1
Net income					57.6			57.6
Common stock dividends					(41.9		)	(41.9		)
Ending balance, June 30, 2020		$66.2		$1,459.0		$926.6			$2,451.8
Three Months Ended June 30, 2019
Beginning balance, March 31, 2019		$66.2		$1,309.0		$804.0			$2,179.2
Net income					42.0			42.0
Common stock dividends					(36.0		)	(36.0		)
Ending balance, June 30, 2019		$66.2		$1,309.0		$810.0			$2,185.2

WPL			Additional					Total
	Common		Paid-In		Retained			Common
	Stock		Capital		Earnings			Equity
Six Months Ended June 30, 2020
Beginning balance, December 31, 2019		$66.2		$1,434.0		$863.4			$2,363.6
Net income					147.2			147.2
Common stock dividends					(84.0		)	(84.0		)
Capital contributions from parent			25.0					25.0
Ending balance, June 30, 2020		$66.2		$1,459.0		$926.6			$2,451.8
Six Months Ended June 30, 2019
Beginning balance, December 31, 2018		$66.2		$1,309.0		$774.3			$2,149.5
Net income					107.7			107.7
Common stock dividends					(72.0		)	(72.0		)
Ending balance, June 30, 2019		$66.2		$1,309.0		$810.0			$2,185.2

XML

Debt

6 Months Ended

Jun. 30, 2020

Debt [Line Items]

Debt

DEBT

NOTE 6(a) Short-term Debt - Information regarding Alliant Energy’s, IPL’s and WPL’s commercial paper, and Alliant Energy’s and WPL’s borrowings under the single credit facility, which currently expires in August 2023, classified as short-term debt was as follows (dollars in millions):

June 30, 2020	Alliant Energy	IPL	WPL
Amount outstanding	$185.4	$—	$37.9
Weighted average interest rates	0.3%	N/A	0.2%
Available credit facility capacity	$814.6	$250.0	$262.1

	Alliant Energy		IPL		WPL
Three Months Ended June 30	2020	2019	2020	2019	2020	2019
Maximum amount outstanding (based on daily outstanding balances)	$270.5	$590.2	$8.4	$—	$182.0	$193.3
Average amount outstanding (based on daily outstanding balances)	$121.2	$531.7	$0.4	$—	$8.7	$141.6
Weighted average interest rates	0.5%	2.7%	0.5%	N/A	0.5%	2.5%
Six Months Ended June 30
Maximum amount outstanding (based on daily outstanding balances)	$462.5	$600.6	$8.4	$50.4	$212.0	$195.1
Average amount outstanding (based on daily outstanding balances)	$251.8	$515.4	$0.2	$0.3	$87.9	$139.8
Weighted average interest rates	1.5%	2.7%	0.5%	2.8%	1.7%	2.5%

NOTE 6(b) Long-term Debt - In March 2020, AEF entered into a $300 million variable rate (1% as of June 30, 2020) term loan credit agreement (with Alliant Energy as guarantor) and used the borrowings under this agreement to retire its $300 million variable rate term loan credit agreement that would have expired in April 2020. AEF’s current term loan credit agreement expires in March 2022 and includes substantially the same financial covenants that are included in Alliant Energy’s credit facility agreement.

In April 2020, WPL issued $350 million of 3.65% debentures due 2050. The net proceeds from the issuance were used by WPL to reduce borrowings under the single credit facility and for general corporate purposes. In June 2020, WPL retired its $150 million 4.6% debentures.

In June 2020, IPL issued $400 million of 2.3% senior debentures due 2030. The net proceeds from the issuance were used by IPL to retire its $200 million 3.65% senior debentures that would have matured in September 2020 and for general corporate purposes.

IPL [Member]

Debt [Line Items]

Debt

DEBT

NOTE 6(a) Short-term Debt - Information regarding Alliant Energy’s, IPL’s and WPL’s commercial paper, and Alliant Energy’s and WPL’s borrowings under the single credit facility, which currently expires in August 2023, classified as short-term debt was as follows (dollars in millions):

June 30, 2020	Alliant Energy	IPL	WPL
Amount outstanding	$185.4	$—	$37.9
Weighted average interest rates	0.3%	N/A	0.2%
Available credit facility capacity	$814.6	$250.0	$262.1

	Alliant Energy		IPL		WPL
Three Months Ended June 30	2020	2019	2020	2019	2020	2019
Maximum amount outstanding (based on daily outstanding balances)	$270.5	$590.2	$8.4	$—	$182.0	$193.3
Average amount outstanding (based on daily outstanding balances)	$121.2	$531.7	$0.4	$—	$8.7	$141.6
Weighted average interest rates	0.5%	2.7%	0.5%	N/A	0.5%	2.5%
Six Months Ended June 30
Maximum amount outstanding (based on daily outstanding balances)	$462.5	$600.6	$8.4	$50.4	$212.0	$195.1
Average amount outstanding (based on daily outstanding balances)	$251.8	$515.4	$0.2	$0.3	$87.9	$139.8
Weighted average interest rates	1.5%	2.7%	0.5%	2.8%	1.7%	2.5%

NOTE 6(b) Long-term Debt - In March 2020, AEF entered into a $300 million variable rate (1% as of June 30, 2020) term loan credit agreement (with Alliant Energy as guarantor) and used the borrowings under this agreement to retire its $300 million variable rate term loan credit agreement that would have expired in April 2020. AEF’s current term loan credit agreement expires in March 2022 and includes substantially the same financial covenants that are included in Alliant Energy’s credit facility agreement.

In April 2020, WPL issued $350 million of 3.65% debentures due 2050. The net proceeds from the issuance were used by WPL to reduce borrowings under the single credit facility and for general corporate purposes. In June 2020, WPL retired its $150 million 4.6% debentures.

In June 2020, IPL issued $400 million of 2.3% senior debentures due 2030. The net proceeds from the issuance were used by IPL to retire its $200 million 3.65% senior debentures that would have matured in September 2020 and for general corporate purposes.

WPL [Member]

Debt [Line Items]

Debt

DEBT

NOTE 6(a) Short-term Debt - Information regarding Alliant Energy’s, IPL’s and WPL’s commercial paper, and Alliant Energy’s and WPL’s borrowings under the single credit facility, which currently expires in August 2023, classified as short-term debt was as follows (dollars in millions):

June 30, 2020	Alliant Energy	IPL	WPL
Amount outstanding	$185.4	$—	$37.9
Weighted average interest rates	0.3%	N/A	0.2%
Available credit facility capacity	$814.6	$250.0	$262.1

	Alliant Energy		IPL		WPL
Three Months Ended June 30	2020	2019	2020	2019	2020	2019
Maximum amount outstanding (based on daily outstanding balances)	$270.5	$590.2	$8.4	$—	$182.0	$193.3
Average amount outstanding (based on daily outstanding balances)	$121.2	$531.7	$0.4	$—	$8.7	$141.6
Weighted average interest rates	0.5%	2.7%	0.5%	N/A	0.5%	2.5%
Six Months Ended June 30
Maximum amount outstanding (based on daily outstanding balances)	$462.5	$600.6	$8.4	$50.4	$212.0	$195.1
Average amount outstanding (based on daily outstanding balances)	$251.8	$515.4	$0.2	$0.3	$87.9	$139.8
Weighted average interest rates	1.5%	2.7%	0.5%	2.8%	1.7%	2.5%

NOTE 6(b) Long-term Debt - In March 2020, AEF entered into a $300 million variable rate (1% as of June 30, 2020) term loan credit agreement (with Alliant Energy as guarantor) and used the borrowings under this agreement to retire its $300 million variable rate term loan credit agreement that would have expired in April 2020. AEF’s current term loan credit agreement expires in March 2022 and includes substantially the same financial covenants that are included in Alliant Energy’s credit facility agreement.

In April 2020, WPL issued $350 million of 3.65% debentures due 2050. The net proceeds from the issuance were used by WPL to reduce borrowings under the single credit facility and for general corporate purposes. In June 2020, WPL retired its $150 million 4.6% debentures.

In June 2020, IPL issued $400 million of 2.3% senior debentures due 2030. The net proceeds from the issuance were used by IPL to retire its $200 million 3.65% senior debentures that would have matured in September 2020 and for general corporate purposes.

XML

Revenues

6 Months Ended

Jun. 30, 2020

Disaggregation of Revenue [Line Items]

Revenues from Contracts with Customers

REVENUES

Disaggregation of revenues from contracts with customers, which correlates to revenues for each reportable segment, was as follows (in millions):

	Alliant Energy				IPL				WPL
Three Months Ended June 30	2020		2019		2020		2019		2020		2019
Electric Utility:
Retail - residential		$249.7		$233.3		$135.3		$125.9		$114.4		$107.4
Retail - commercial	164.0		171.3		109.0		111.4		55.0		59.9
Retail - industrial	197.3		214.2		114.3		118.4		83.0		95.8
Wholesale	39.1		41.0		13.0		14.6		26.1		26.4
Bulk power and other	25.1		31.4		16.8		22.0		8.3		9.4
Total Electric Utility	675.2		691.2		388.4		392.3		286.8		298.9
Gas Utility:
Retail - residential	33.6		35.2		18.5		20.0		15.1		15.2
Retail - commercial	14.7		16.1		8.3		8.8		6.4		7.3
Retail - industrial	1.7		2.0		1.3		1.6		0.4		0.4
Transportation/other	8.9		11.9		5.8		8.0		3.1		3.9
Total Gas Utility	58.9		65.2		33.9		38.4		25.0		26.8
Other Utility:
Steam	8.6		9.2		8.6		9.2		—		—
Other utility	1.5		1.7		1.0		1.3		0.5		0.4
Total Other Utility	10.1		10.9		9.6		10.5		0.5		0.4
Non-Utility and Other:
Transportation and other	18.9		22.9		—		—		—		—
Total Non-Utility and Other	18.9		22.9		—		—		—		—
Total revenues		$763.1		$790.2		$431.9		$441.2		$312.3		$326.1

	Alliant Energy				IPL				WPL
Six Months Ended June 30	2020		2019		2020		2019		2020		2019
Electric Utility:
Retail - residential		$516.5		$508.0		$282.7		$273.4		$233.8		$234.6
Retail - commercial	346.3		352.4		228.7		228.0		117.6		124.4
Retail - industrial	407.2		422.9		235.5		234.5		171.7		188.4
Wholesale	80.0		87.5		27.4		31.5		52.6		56.0
Bulk power and other	55.5		63.8		38.9		44.7		16.6		19.1
Total Electric Utility	1,405.5		1,434.6		813.2		812.1		592.3		622.5
Gas Utility:
Retail - residential	124.1		167.0		67.3		97.9		56.8		69.1
Retail - commercial	60.4		79.7		32.4		43.6		28.0		36.1
Retail - industrial	5.9		7.4		3.6		4.8		2.3		2.6
Transportation/other	20.7		26.9		13.6		16.7		7.1		10.2
Total Gas Utility	211.1		281.0		116.9		163.0		94.2		118.0
Other Utility:
Steam	18.6		17.6		18.6		17.6		—		—
Other utility	3.1		4.4		2.1		3.6		1.0		0.8
Total Other Utility	21.7		22.0		20.7		21.2		1.0		0.8
Non-Utility and Other:
Transportation and other	40.5		39.8		—		—		—		—
Total Non-Utility and Other	40.5		39.8		—		—		—		—
Total revenues		$1,678.8		$1,777.4		$950.8		$996.3		$687.5		$741.3

IPL [Member]

Disaggregation of Revenue [Line Items]

Revenues from Contracts with Customers

REVENUES

Disaggregation of revenues from contracts with customers, which correlates to revenues for each reportable segment, was as follows (in millions):

	Alliant Energy				IPL				WPL
Three Months Ended June 30	2020		2019		2020		2019		2020		2019
Electric Utility:
Retail - residential		$249.7		$233.3		$135.3		$125.9		$114.4		$107.4
Retail - commercial	164.0		171.3		109.0		111.4		55.0		59.9
Retail - industrial	197.3		214.2		114.3		118.4		83.0		95.8
Wholesale	39.1		41.0		13.0		14.6		26.1		26.4
Bulk power and other	25.1		31.4		16.8		22.0		8.3		9.4
Total Electric Utility	675.2		691.2		388.4		392.3		286.8		298.9
Gas Utility:
Retail - residential	33.6		35.2		18.5		20.0		15.1		15.2
Retail - commercial	14.7		16.1		8.3		8.8		6.4		7.3
Retail - industrial	1.7		2.0		1.3		1.6		0.4		0.4
Transportation/other	8.9		11.9		5.8		8.0		3.1		3.9
Total Gas Utility	58.9		65.2		33.9		38.4		25.0		26.8
Other Utility:
Steam	8.6		9.2		8.6		9.2		—		—
Other utility	1.5		1.7		1.0		1.3		0.5		0.4
Total Other Utility	10.1		10.9		9.6		10.5		0.5		0.4
Non-Utility and Other:
Transportation and other	18.9		22.9		—		—		—		—
Total Non-Utility and Other	18.9		22.9		—		—		—		—
Total revenues		$763.1		$790.2		$431.9		$441.2		$312.3		$326.1

	Alliant Energy				IPL				WPL
Six Months Ended June 30	2020		2019		2020		2019		2020		2019
Electric Utility:
Retail - residential		$516.5		$508.0		$282.7		$273.4		$233.8		$234.6
Retail - commercial	346.3		352.4		228.7		228.0		117.6		124.4
Retail - industrial	407.2		422.9		235.5		234.5		171.7		188.4
Wholesale	80.0		87.5		27.4		31.5		52.6		56.0
Bulk power and other	55.5		63.8		38.9		44.7		16.6		19.1
Total Electric Utility	1,405.5		1,434.6		813.2		812.1		592.3		622.5
Gas Utility:
Retail - residential	124.1		167.0		67.3		97.9		56.8		69.1
Retail - commercial	60.4		79.7		32.4		43.6		28.0		36.1
Retail - industrial	5.9		7.4		3.6		4.8		2.3		2.6
Transportation/other	20.7		26.9		13.6		16.7		7.1		10.2
Total Gas Utility	211.1		281.0		116.9		163.0		94.2		118.0
Other Utility:
Steam	18.6		17.6		18.6		17.6		—		—
Other utility	3.1		4.4		2.1		3.6		1.0		0.8
Total Other Utility	21.7		22.0		20.7		21.2		1.0		0.8
Non-Utility and Other:
Transportation and other	40.5		39.8		—		—		—		—
Total Non-Utility and Other	40.5		39.8		—		—		—		—
Total revenues		$1,678.8		$1,777.4		$950.8		$996.3		$687.5		$741.3

WPL [Member]

Disaggregation of Revenue [Line Items]

Revenues from Contracts with Customers

REVENUES

Disaggregation of revenues from contracts with customers, which correlates to revenues for each reportable segment, was as follows (in millions):

	Alliant Energy				IPL				WPL
Three Months Ended June 30	2020		2019		2020		2019		2020		2019
Electric Utility:
Retail - residential		$249.7		$233.3		$135.3		$125.9		$114.4		$107.4
Retail - commercial	164.0		171.3		109.0		111.4		55.0		59.9
Retail - industrial	197.3		214.2		114.3		118.4		83.0		95.8
Wholesale	39.1		41.0		13.0		14.6		26.1		26.4
Bulk power and other	25.1		31.4		16.8		22.0		8.3		9.4
Total Electric Utility	675.2		691.2		388.4		392.3		286.8		298.9
Gas Utility:
Retail - residential	33.6		35.2		18.5		20.0		15.1		15.2
Retail - commercial	14.7		16.1		8.3		8.8		6.4		7.3
Retail - industrial	1.7		2.0		1.3		1.6		0.4		0.4
Transportation/other	8.9		11.9		5.8		8.0		3.1		3.9
Total Gas Utility	58.9		65.2		33.9		38.4		25.0		26.8
Other Utility:
Steam	8.6		9.2		8.6		9.2		—		—
Other utility	1.5		1.7		1.0		1.3		0.5		0.4
Total Other Utility	10.1		10.9		9.6		10.5		0.5		0.4
Non-Utility and Other:
Transportation and other	18.9		22.9		—		—		—		—
Total Non-Utility and Other	18.9		22.9		—		—		—		—
Total revenues		$763.1		$790.2		$431.9		$441.2		$312.3		$326.1

	Alliant Energy				IPL				WPL
Six Months Ended June 30	2020		2019		2020		2019		2020		2019
Electric Utility:
Retail - residential		$516.5		$508.0		$282.7		$273.4		$233.8		$234.6
Retail - commercial	346.3		352.4		228.7		228.0		117.6		124.4
Retail - industrial	407.2		422.9		235.5		234.5		171.7		188.4
Wholesale	80.0		87.5		27.4		31.5		52.6		56.0
Bulk power and other	55.5		63.8		38.9		44.7		16.6		19.1
Total Electric Utility	1,405.5		1,434.6		813.2		812.1		592.3		622.5
Gas Utility:
Retail - residential	124.1		167.0		67.3		97.9		56.8		69.1
Retail - commercial	60.4		79.7		32.4		43.6		28.0		36.1
Retail - industrial	5.9		7.4		3.6		4.8		2.3		2.6
Transportation/other	20.7		26.9		13.6		16.7		7.1		10.2
Total Gas Utility	211.1		281.0		116.9		163.0		94.2		118.0
Other Utility:
Steam	18.6		17.6		18.6		17.6		—		—
Other utility	3.1		4.4		2.1		3.6		1.0		0.8
Total Other Utility	21.7		22.0		20.7		21.2		1.0		0.8
Non-Utility and Other:
Transportation and other	40.5		39.8		—		—		—		—
Total Non-Utility and Other	40.5		39.8		—		—		—		—
Total revenues		$1,678.8		$1,777.4		$950.8		$996.3		$687.5		$741.3

XML

Income Taxes

6 Months Ended

Jun. 30, 2020

Income Taxes [Line Items]

Income Taxes

INCOME TAXES

Income Tax Rates - Overall effective income tax rates, which were computed by dividing income tax expense (benefit) by income before income taxes, were as follows. The effective income tax rates were different than the federal statutory rate primarily due to state income taxes, production tax credits, amortization of excess deferred taxes and the effect of rate-making on property-related differences. The decreases in overall effective income tax rates for the three and six months ended June 30, 2020 compared to the same periods in 2019 were primarily due to increases in production tax credits as a result of increased wind production in 2020 and increased amortization of excess deferred taxes primarily at WPL, which were used to offset increases in WPL’s 2020 increased revenue requirements.

	Alliant Energy				IPL				WPL
	Three Months		Six Months		Three Months		Six Months		Three Months		Six Months
	2020	2019	2020	2019	2020	2019	2020	2019	2020	2019	2020	2019
Overall income tax rate	(6.5%)	10.3%	(9.6%)	10.5%	(6.5%)	3.8%	(13.8%)	3.7%	(8.5%)	15.5%	(9.4%)	17.2%

Deferred Tax Assets and Liabilities -

Carryforwards - At June 30, 2020, carryforwards and expiration dates were estimated as follows (in millions):

	Range of Expiration Dates	Alliant Energy		IPL		WPL
Federal net operating losses	2037		$299		$276		$3
State net operating losses	2020-2040	595		9		2
Federal tax credits	2022-2040	403		212		170

IPL [Member]

Income Taxes [Line Items]

Income Taxes

INCOME TAXES

Income Tax Rates - Overall effective income tax rates, which were computed by dividing income tax expense (benefit) by income before income taxes, were as follows. The effective income tax rates were different than the federal statutory rate primarily due to state income taxes, production tax credits, amortization of excess deferred taxes and the effect of rate-making on property-related differences. The decreases in overall effective income tax rates for the three and six months ended June 30, 2020 compared to the same periods in 2019 were primarily due to increases in production tax credits as a result of increased wind production in 2020 and increased amortization of excess deferred taxes primarily at WPL, which were used to offset increases in WPL’s 2020 increased revenue requirements.

	Alliant Energy				IPL				WPL
	Three Months		Six Months		Three Months		Six Months		Three Months		Six Months
	2020	2019	2020	2019	2020	2019	2020	2019	2020	2019	2020	2019
Overall income tax rate	(6.5%)	10.3%	(9.6%)	10.5%	(6.5%)	3.8%	(13.8%)	3.7%	(8.5%)	15.5%	(9.4%)	17.2%

Deferred Tax Assets and Liabilities -

Carryforwards - At June 30, 2020, carryforwards and expiration dates were estimated as follows (in millions):

	Range of Expiration Dates	Alliant Energy		IPL		WPL
Federal net operating losses	2037		$299		$276		$3
State net operating losses	2020-2040	595		9		2
Federal tax credits	2022-2040	403		212		170

WPL [Member]

Income Taxes [Line Items]

Income Taxes

INCOME TAXES

Income Tax Rates - Overall effective income tax rates, which were computed by dividing income tax expense (benefit) by income before income taxes, were as follows. The effective income tax rates were different than the federal statutory rate primarily due to state income taxes, production tax credits, amortization of excess deferred taxes and the effect of rate-making on property-related differences. The decreases in overall effective income tax rates for the three and six months ended June 30, 2020 compared to the same periods in 2019 were primarily due to increases in production tax credits as a result of increased wind production in 2020 and increased amortization of excess deferred taxes primarily at WPL, which were used to offset increases in WPL’s 2020 increased revenue requirements.

	Alliant Energy				IPL				WPL
	Three Months		Six Months		Three Months		Six Months		Three Months		Six Months
	2020	2019	2020	2019	2020	2019	2020	2019	2020	2019	2020	2019
Overall income tax rate	(6.5%)	10.3%	(9.6%)	10.5%	(6.5%)	3.8%	(13.8%)	3.7%	(8.5%)	15.5%	(9.4%)	17.2%

Deferred Tax Assets and Liabilities -

Carryforwards - At June 30, 2020, carryforwards and expiration dates were estimated as follows (in millions):

	Range of Expiration Dates	Alliant Energy		IPL		WPL
Federal net operating losses	2037		$299		$276		$3
State net operating losses	2020-2040	595		9		2
Federal tax credits	2022-2040	403		212		170

XML

Benefit Plans

6 Months Ended

Jun. 30, 2020

Benefit Plans

BENEFIT PLANS

NOTE 9(a) Pension and OPEB Plans -

Net Periodic Benefit Costs - The components of net periodic benefit costs for sponsored defined benefit pension and OPEB plans for the three and six months ended June 30 are included below (in millions). For IPL and WPL, amounts represent those for their plan participants covered under plans they sponsor, as well as amounts directly assigned to them related to certain participants in the Alliant Energy and Corporate Services sponsored plans.

	Defined Benefit Pension Plans												OPEB Plans
	Three Months						Six Months						Three Months						Six Months
Alliant Energy	2020			2019			2020			2019			2020			2019			2020			2019
Service cost		$2.7			$2.4			$5.4			$4.8			$0.9			$0.9			$1.7			$1.7
Interest cost	10.8			12.4			21.6			24.9			1.7			2.1			3.5			4.2
Expected return on plan assets	(17.5		)	(15.0		)	(34.9		)	(30.0		)	(1.4		)	(1.3		)	(2.7		)	(2.5		)
Amortization of prior service credit	(0.1		)	(0.1		)	(0.3		)	(0.3		)	—			(0.1		)	—			(0.1		)
Amortization of actuarial loss	8.6			9.1			17.2			18.2			0.9			0.8			1.7			1.6
Settlement losses (a)	—			—			4.2			—			—			—			—			—
		$4.5			$8.8			$13.2			$17.6			$2.1			$2.4			$4.2			$4.9

	Defined Benefit Pension Plans												OPEB Plans
	Three Months						Six Months						Three Months						Six Months
IPL	2020			2019			2020			2019			2020			2019			2020			2019
Service cost		$1.7			$1.5			$3.4			$3.0			$0.4			$0.4			$0.7			$0.7
Interest cost	5.0			5.7			10.0			11.4			0.7			0.9			1.4			1.7
Expected return on plan assets	(8.2		)	(7.1		)	(16.3		)	(14.1		)	(0.9		)	(0.9		)	(1.9		)	(1.8		)
Amortization of prior service credit	—			—			(0.1		)	(0.1		)	—			—			—			—
Amortization of actuarial loss	3.7			4.0			7.4			7.9			0.2			0.3			0.5			0.7
		$2.2			$4.1			$4.4			$8.1			$0.4			$0.7			$0.7			$1.3

	Defined Benefit Pension Plans												OPEB Plans
	Three Months						Six Months						Three Months						Six Months
WPL	2020			2019			2020			2019			2020			2019			2020			2019
Service cost		$0.9			$0.8			$1.9			$1.7			$0.3			$0.3			$0.6			$0.6
Interest cost	4.7			5.4			9.4			10.8			0.7			0.9			1.4			1.7
Expected return on plan assets	(7.6		)	(6.6		)	(15.2		)	(13.1		)	(0.1		)	(0.2		)	(0.3		)	(0.3		)
Amortization of prior service credit	—			—			(0.1		)	(0.1		)	—			(0.1		)	—			(0.1		)
Amortization of actuarial loss	4.1			4.4			8.2			8.8			0.5			0.4			1.0			0.8
		$2.1			$4.0			$4.2			$8.1			$1.4			$1.3			$2.7			$2.7

(a) Settlement losses related to payments made to retired executives of Alliant Energy.

NOTE 9(b) Equity-based Compensation Plans - A summary of compensation expense, including amounts allocated to IPL and WPL, and the related income tax benefits recognized for share-based compensation awards for the three and six months ended June 30 was as follows (in millions):

	Alliant Energy								IPL								WPL
	Three Months				Six Months				Three Months				Six Months				Three Months				Six Months
	2020		2019		2020		2019		2020		2019		2020		2019		2020		2019		2020		2019
Compensation expense		$2.7		$3.4		$5.4		$8.1		$1.5		$1.9		$2.9		$4.5		$1.2		$1.4		$2.3		$3.2
Income tax benefits	0.8		1.0		1.5		2.3		0.4		0.5		0.8		1.3		0.3		0.4		0.6		0.9

As of June 30, 2020, Alliant Energy’s, IPL’s and WPL’s total unrecognized compensation cost related to share-based compensation awards was $9.9 million, $5.5 million and $4.1 million, respectively, which is expected to be recognized over a weighted average period of between 1 year and 2 years.

For the six months ended June 30, 2020, performance shares, performance restricted stock units and restricted stock units were granted to key employees as follows. These shares and units will be paid out in shares of common stock, and are therefore accounted for as equity awards. As of June 30, 2020, 228,207 shares were included in the calculation of diluted EPS related to the nonvested equity awards.

		Weighted Average
	Grants	Grant Date Fair Value
Performance shares	55,303		$64.04
Performance restricted stock units	55,303	59.47
Restricted stock units	60,284	59.49

IPL [Member]

Benefit Plans

BENEFIT PLANS

NOTE 9(a) Pension and OPEB Plans -

Net Periodic Benefit Costs - The components of net periodic benefit costs for sponsored defined benefit pension and OPEB plans for the three and six months ended June 30 are included below (in millions). For IPL and WPL, amounts represent those for their plan participants covered under plans they sponsor, as well as amounts directly assigned to them related to certain participants in the Alliant Energy and Corporate Services sponsored plans.

	Defined Benefit Pension Plans												OPEB Plans
	Three Months						Six Months						Three Months						Six Months
Alliant Energy	2020			2019			2020			2019			2020			2019			2020			2019
Service cost		$2.7			$2.4			$5.4			$4.8			$0.9			$0.9			$1.7			$1.7
Interest cost	10.8			12.4			21.6			24.9			1.7			2.1			3.5			4.2
Expected return on plan assets	(17.5		)	(15.0		)	(34.9		)	(30.0		)	(1.4		)	(1.3		)	(2.7		)	(2.5		)
Amortization of prior service credit	(0.1		)	(0.1		)	(0.3		)	(0.3		)	—			(0.1		)	—			(0.1		)
Amortization of actuarial loss	8.6			9.1			17.2			18.2			0.9			0.8			1.7			1.6
Settlement losses (a)	—			—			4.2			—			—			—			—			—
		$4.5			$8.8			$13.2			$17.6			$2.1			$2.4			$4.2			$4.9

	Defined Benefit Pension Plans												OPEB Plans
	Three Months						Six Months						Three Months						Six Months
IPL	2020			2019			2020			2019			2020			2019			2020			2019
Service cost		$1.7			$1.5			$3.4			$3.0			$0.4			$0.4			$0.7			$0.7
Interest cost	5.0			5.7			10.0			11.4			0.7			0.9			1.4			1.7
Expected return on plan assets	(8.2		)	(7.1		)	(16.3		)	(14.1		)	(0.9		)	(0.9		)	(1.9		)	(1.8		)
Amortization of prior service credit	—			—			(0.1		)	(0.1		)	—			—			—			—
Amortization of actuarial loss	3.7			4.0			7.4			7.9			0.2			0.3			0.5			0.7
		$2.2			$4.1			$4.4			$8.1			$0.4			$0.7			$0.7			$1.3

	Defined Benefit Pension Plans												OPEB Plans
	Three Months						Six Months						Three Months						Six Months
WPL	2020			2019			2020			2019			2020			2019			2020			2019
Service cost		$0.9			$0.8			$1.9			$1.7			$0.3			$0.3			$0.6			$0.6
Interest cost	4.7			5.4			9.4			10.8			0.7			0.9			1.4			1.7
Expected return on plan assets	(7.6		)	(6.6		)	(15.2		)	(13.1		)	(0.1		)	(0.2		)	(0.3		)	(0.3		)
Amortization of prior service credit	—			—			(0.1		)	(0.1		)	—			(0.1		)	—			(0.1		)
Amortization of actuarial loss	4.1			4.4			8.2			8.8			0.5			0.4			1.0			0.8
		$2.1			$4.0			$4.2			$8.1			$1.4			$1.3			$2.7			$2.7

(a) Settlement losses related to payments made to retired executives of Alliant Energy.

NOTE 9(b) Equity-based Compensation Plans - A summary of compensation expense, including amounts allocated to IPL and WPL, and the related income tax benefits recognized for share-based compensation awards for the three and six months ended June 30 was as follows (in millions):

	Alliant Energy								IPL								WPL
	Three Months				Six Months				Three Months				Six Months				Three Months				Six Months
	2020		2019		2020		2019		2020		2019		2020		2019		2020		2019		2020		2019
Compensation expense		$2.7		$3.4		$5.4		$8.1		$1.5		$1.9		$2.9		$4.5		$1.2		$1.4		$2.3		$3.2
Income tax benefits	0.8		1.0		1.5		2.3		0.4		0.5		0.8		1.3		0.3		0.4		0.6		0.9

As of June 30, 2020, Alliant Energy’s, IPL’s and WPL’s total unrecognized compensation cost related to share-based compensation awards was $9.9 million, $5.5 million and $4.1 million, respectively, which is expected to be recognized over a weighted average period of between 1 year and 2 years.

For the six months ended June 30, 2020, performance shares, performance restricted stock units and restricted stock units were granted to key employees as follows. These shares and units will be paid out in shares of common stock, and are therefore accounted for as equity awards. As of June 30, 2020, 228,207 shares were included in the calculation of diluted EPS related to the nonvested equity awards.

		Weighted Average
	Grants	Grant Date Fair Value
Performance shares	55,303		$64.04
Performance restricted stock units	55,303	59.47
Restricted stock units	60,284	59.49

WPL [Member]

Benefit Plans

BENEFIT PLANS

NOTE 9(a) Pension and OPEB Plans -

Net Periodic Benefit Costs - The components of net periodic benefit costs for sponsored defined benefit pension and OPEB plans for the three and six months ended June 30 are included below (in millions). For IPL and WPL, amounts represent those for their plan participants covered under plans they sponsor, as well as amounts directly assigned to them related to certain participants in the Alliant Energy and Corporate Services sponsored plans.

	Defined Benefit Pension Plans												OPEB Plans
	Three Months						Six Months						Three Months						Six Months
Alliant Energy	2020			2019			2020			2019			2020			2019			2020			2019
Service cost		$2.7			$2.4			$5.4			$4.8			$0.9			$0.9			$1.7			$1.7
Interest cost	10.8			12.4			21.6			24.9			1.7			2.1			3.5			4.2
Expected return on plan assets	(17.5		)	(15.0		)	(34.9		)	(30.0		)	(1.4		)	(1.3		)	(2.7		)	(2.5		)
Amortization of prior service credit	(0.1		)	(0.1		)	(0.3		)	(0.3		)	—			(0.1		)	—			(0.1		)
Amortization of actuarial loss	8.6			9.1			17.2			18.2			0.9			0.8			1.7			1.6
Settlement losses (a)	—			—			4.2			—			—			—			—			—
		$4.5			$8.8			$13.2			$17.6			$2.1			$2.4			$4.2			$4.9

	Defined Benefit Pension Plans												OPEB Plans
	Three Months						Six Months						Three Months						Six Months
IPL	2020			2019			2020			2019			2020			2019			2020			2019
Service cost		$1.7			$1.5			$3.4			$3.0			$0.4			$0.4			$0.7			$0.7
Interest cost	5.0			5.7			10.0			11.4			0.7			0.9			1.4			1.7
Expected return on plan assets	(8.2		)	(7.1		)	(16.3		)	(14.1		)	(0.9		)	(0.9		)	(1.9		)	(1.8		)
Amortization of prior service credit	—			—			(0.1		)	(0.1		)	—			—			—			—
Amortization of actuarial loss	3.7			4.0			7.4			7.9			0.2			0.3			0.5			0.7
		$2.2			$4.1			$4.4			$8.1			$0.4			$0.7			$0.7			$1.3

	Defined Benefit Pension Plans												OPEB Plans
	Three Months						Six Months						Three Months						Six Months
WPL	2020			2019			2020			2019			2020			2019			2020			2019
Service cost		$0.9			$0.8			$1.9			$1.7			$0.3			$0.3			$0.6			$0.6
Interest cost	4.7			5.4			9.4			10.8			0.7			0.9			1.4			1.7
Expected return on plan assets	(7.6		)	(6.6		)	(15.2		)	(13.1		)	(0.1		)	(0.2		)	(0.3		)	(0.3		)
Amortization of prior service credit	—			—			(0.1		)	(0.1		)	—			(0.1		)	—			(0.1		)
Amortization of actuarial loss	4.1			4.4			8.2			8.8			0.5			0.4			1.0			0.8
		$2.1			$4.0			$4.2			$8.1			$1.4			$1.3			$2.7			$2.7

(a) Settlement losses related to payments made to retired executives of Alliant Energy.

NOTE 9(b) Equity-based Compensation Plans - A summary of compensation expense, including amounts allocated to IPL and WPL, and the related income tax benefits recognized for share-based compensation awards for the three and six months ended June 30 was as follows (in millions):

	Alliant Energy								IPL								WPL
	Three Months				Six Months				Three Months				Six Months				Three Months				Six Months
	2020		2019		2020		2019		2020		2019		2020		2019		2020		2019		2020		2019
Compensation expense		$2.7		$3.4		$5.4		$8.1		$1.5		$1.9		$2.9		$4.5		$1.2		$1.4		$2.3		$3.2
Income tax benefits	0.8		1.0		1.5		2.3		0.4		0.5		0.8		1.3		0.3		0.4		0.6		0.9

As of June 30, 2020, Alliant Energy’s, IPL’s and WPL’s total unrecognized compensation cost related to share-based compensation awards was $9.9 million, $5.5 million and $4.1 million, respectively, which is expected to be recognized over a weighted average period of between 1 year and 2 years.

For the six months ended June 30, 2020, performance shares, performance restricted stock units and restricted stock units were granted to key employees as follows. These shares and units will be paid out in shares of common stock, and are therefore accounted for as equity awards. As of June 30, 2020, 228,207 shares were included in the calculation of diluted EPS related to the nonvested equity awards.

		Weighted Average
	Grants	Grant Date Fair Value
Performance shares	55,303		$64.04
Performance restricted stock units	55,303	59.47
Restricted stock units	60,284	59.49

XML

Asset Retirement Obligations

6 Months Ended

Jun. 30, 2020

Asset Retirement Obligations [Line Items]

Asset Retirement Obligations

ASSET RETIREMENT OBLIGATIONS

A reconciliation of the changes in asset retirement obligations associated with long-lived assets for the six months ended June 30, 2020 is as follows (in millions):

	Alliant Energy			IPL
Balance, January 1		$196.3			$133.9
Revisions in estimated cash flows	0.9			—
Liabilities settled	(3.5		)	(2.8		)
Liabilities incurred (a)	27.6			27.6
Accretion expense	3.5			2.5
Balance, June 30		$224.8			$161.2

(a)

During the six months ended June 30, 2020, Alliant Energy and IPL recognized additional asset retirement obligations related to IPL’s newly constructed Whispering Willow North and Golden Plains wind sites. The increases in asset retirement obligations resulted in corresponding increases in property, plant and equipment, net on the respective balance sheets.

IPL [Member]

Asset Retirement Obligations [Line Items]

Asset Retirement Obligations

ASSET RETIREMENT OBLIGATIONS

A reconciliation of the changes in asset retirement obligations associated with long-lived assets for the six months ended June 30, 2020 is as follows (in millions):

	Alliant Energy			IPL
Balance, January 1		$196.3			$133.9
Revisions in estimated cash flows	0.9			—
Liabilities settled	(3.5		)	(2.8		)
Liabilities incurred (a)	27.6			27.6
Accretion expense	3.5			2.5
Balance, June 30		$224.8			$161.2

(a)

During the six months ended June 30, 2020, Alliant Energy and IPL recognized additional asset retirement obligations related to IPL’s newly constructed Whispering Willow North and Golden Plains wind sites. The increases in asset retirement obligations resulted in corresponding increases in property, plant and equipment, net on the respective balance sheets.

XML

Derivative Instruments

6 Months Ended

Jun. 30, 2020

Derivative Instruments [Line Items]

Derivative Instruments

DERIVATIVE INSTRUMENTS

Commodity Derivatives -

Notional Amounts - As of June 30, 2020, gross notional amounts and settlement/delivery years related to outstanding swap contracts, option contracts, physical forward contracts and FTRs that were accounted for as commodity derivative instruments were as follows (units in thousands):

	FTRs		Natural Gas		Coal		Diesel Fuel
	MWhs	Years	Dths	Years	Tons	Years	Gallons	Years
Alliant Energy	21,455	2020-2021	234,304	2020-2028	4,482	2020-2021	6,804	2020-2022
IPL	8,978	2020-2021	123,308	2020-2028	1,834	2020-2021	—	—
WPL	12,477	2020-2021	110,996	2020-2027	2,648	2020-2021	6,804	2020-2022

Financial Statement Presentation - Derivative instruments are recorded at fair value each reporting date on the balance sheets as assets or liabilities as follows (in millions):

	Alliant Energy				IPL				WPL
	June 30, 2020		December 31, 2019		June 30, 2020		December 31, 2019		June 30, 2020		December 31, 2019
Current derivative assets		$27.9		$15.8		$22.5		$12.1		$5.4		$3.7
Non-current derivative assets	14.5		11.0		14.5		10.2		—		0.8
Current derivative liabilities	20.0		19.0		8.5		8.9		11.5		10.1
Non-current derivative liabilities	26.2		18.6		11.8		8.5		14.4		10.1

Credit Risk-related Contingent Features - Various agreements contain credit risk-related contingent features, including requirements to maintain certain credit ratings and/or limitations on liability positions under the agreements based on credit ratings. Certain of these agreements with credit risk-related contingency features are accounted for as derivative instruments. In the event of a material change in creditworthiness or if liability positions exceed certain contractual limits, credit support may need to be provided in the form of letters of credit or cash collateral up to the amount of exposure under the contracts, or the contracts may need to be unwound and underlying liability positions paid. At June 30, 2020 and December 31, 2019, the aggregate fair value of all derivative instruments with credit risk-related contingent features in a net liability position was not materially different than amounts that would be required to be posted as credit support to counterparties by Alliant Energy, IPL or WPL if the most restrictive credit risk-related contingent features for derivative agreements in a net liability position were triggered.

Balance Sheet Offsetting - The fair value amounts of derivative instruments subject to a master netting arrangement are not netted by counterparty on the balance sheets. However, if the fair value amounts of derivative instruments by counterparty were netted, amounts would not be materially different from gross amounts of derivative assets and derivative liabilities at June 30, 2020 and December 31, 2019. Fair value amounts recognized for the right to reclaim cash collateral (receivable) or the obligation to return cash collateral (payable) are not offset against fair value amounts recognized for derivative instruments executed with the same counterparty under the same master netting arrangement.

IPL [Member]

Derivative Instruments [Line Items]

Derivative Instruments

DERIVATIVE INSTRUMENTS

Commodity Derivatives -

Notional Amounts - As of June 30, 2020, gross notional amounts and settlement/delivery years related to outstanding swap contracts, option contracts, physical forward contracts and FTRs that were accounted for as commodity derivative instruments were as follows (units in thousands):

	FTRs		Natural Gas		Coal		Diesel Fuel
	MWhs	Years	Dths	Years	Tons	Years	Gallons	Years
Alliant Energy	21,455	2020-2021	234,304	2020-2028	4,482	2020-2021	6,804	2020-2022
IPL	8,978	2020-2021	123,308	2020-2028	1,834	2020-2021	—	—
WPL	12,477	2020-2021	110,996	2020-2027	2,648	2020-2021	6,804	2020-2022

Financial Statement Presentation - Derivative instruments are recorded at fair value each reporting date on the balance sheets as assets or liabilities as follows (in millions):

	Alliant Energy				IPL				WPL
	June 30, 2020		December 31, 2019		June 30, 2020		December 31, 2019		June 30, 2020		December 31, 2019
Current derivative assets		$27.9		$15.8		$22.5		$12.1		$5.4		$3.7
Non-current derivative assets	14.5		11.0		14.5		10.2		—		0.8
Current derivative liabilities	20.0		19.0		8.5		8.9		11.5		10.1
Non-current derivative liabilities	26.2		18.6		11.8		8.5		14.4		10.1

Credit Risk-related Contingent Features - Various agreements contain credit risk-related contingent features, including requirements to maintain certain credit ratings and/or limitations on liability positions under the agreements based on credit ratings. Certain of these agreements with credit risk-related contingency features are accounted for as derivative instruments. In the event of a material change in creditworthiness or if liability positions exceed certain contractual limits, credit support may need to be provided in the form of letters of credit or cash collateral up to the amount of exposure under the contracts, or the contracts may need to be unwound and underlying liability positions paid. At June 30, 2020 and December 31, 2019, the aggregate fair value of all derivative instruments with credit risk-related contingent features in a net liability position was not materially different than amounts that would be required to be posted as credit support to counterparties by Alliant Energy, IPL or WPL if the most restrictive credit risk-related contingent features for derivative agreements in a net liability position were triggered.

Balance Sheet Offsetting - The fair value amounts of derivative instruments subject to a master netting arrangement are not netted by counterparty on the balance sheets. However, if the fair value amounts of derivative instruments by counterparty were netted, amounts would not be materially different from gross amounts of derivative assets and derivative liabilities at June 30, 2020 and December 31, 2019. Fair value amounts recognized for the right to reclaim cash collateral (receivable) or the obligation to return cash collateral (payable) are not offset against fair value amounts recognized for derivative instruments executed with the same counterparty under the same master netting arrangement.

WPL [Member]

Derivative Instruments [Line Items]

Derivative Instruments

DERIVATIVE INSTRUMENTS

Commodity Derivatives -

Notional Amounts - As of June 30, 2020, gross notional amounts and settlement/delivery years related to outstanding swap contracts, option contracts, physical forward contracts and FTRs that were accounted for as commodity derivative instruments were as follows (units in thousands):

	FTRs		Natural Gas		Coal		Diesel Fuel
	MWhs	Years	Dths	Years	Tons	Years	Gallons	Years
Alliant Energy	21,455	2020-2021	234,304	2020-2028	4,482	2020-2021	6,804	2020-2022
IPL	8,978	2020-2021	123,308	2020-2028	1,834	2020-2021	—	—
WPL	12,477	2020-2021	110,996	2020-2027	2,648	2020-2021	6,804	2020-2022

Financial Statement Presentation - Derivative instruments are recorded at fair value each reporting date on the balance sheets as assets or liabilities as follows (in millions):

	Alliant Energy				IPL				WPL
	June 30, 2020		December 31, 2019		June 30, 2020		December 31, 2019		June 30, 2020		December 31, 2019
Current derivative assets		$27.9		$15.8		$22.5		$12.1		$5.4		$3.7
Non-current derivative assets	14.5		11.0		14.5		10.2		—		0.8
Current derivative liabilities	20.0		19.0		8.5		8.9		11.5		10.1
Non-current derivative liabilities	26.2		18.6		11.8		8.5		14.4		10.1

Credit Risk-related Contingent Features - Various agreements contain credit risk-related contingent features, including requirements to maintain certain credit ratings and/or limitations on liability positions under the agreements based on credit ratings. Certain of these agreements with credit risk-related contingency features are accounted for as derivative instruments. In the event of a material change in creditworthiness or if liability positions exceed certain contractual limits, credit support may need to be provided in the form of letters of credit or cash collateral up to the amount of exposure under the contracts, or the contracts may need to be unwound and underlying liability positions paid. At June 30, 2020 and December 31, 2019, the aggregate fair value of all derivative instruments with credit risk-related contingent features in a net liability position was not materially different than amounts that would be required to be posted as credit support to counterparties by Alliant Energy, IPL or WPL if the most restrictive credit risk-related contingent features for derivative agreements in a net liability position were triggered.

Balance Sheet Offsetting - The fair value amounts of derivative instruments subject to a master netting arrangement are not netted by counterparty on the balance sheets. However, if the fair value amounts of derivative instruments by counterparty were netted, amounts would not be materially different from gross amounts of derivative assets and derivative liabilities at June 30, 2020 and December 31, 2019. Fair value amounts recognized for the right to reclaim cash collateral (receivable) or the obligation to return cash collateral (payable) are not offset against fair value amounts recognized for derivative instruments executed with the same counterparty under the same master netting arrangement.

XML

Fair Value Measurements

6 Months Ended

Jun. 30, 2020

Fair Value Measurements

FAIR VALUE MEASUREMENTS

Fair Value of Financial Instruments - The carrying amounts of current assets and current liabilities approximate fair value because of the short maturity of such financial instruments. Carrying amounts and related estimated fair values of other financial instruments were as follows (in millions):

Alliant Energy	June 30, 2020										December 31, 2019
			Fair Value										Fair Value
	Carrying		Level		Level		Level				Carrying		Level		Level		Level
	Amount		1		2		3		Total		Amount		1		2		3		Total
Assets:
Money market fund investments		$198.3		$198.3		$—		$—		$198.3		$5.4		$5.4		$—		$—		$5.4
Derivatives	42.4		—		4.6		37.8		42.4		26.8		—		4.8		22.0		26.8
Deferred proceeds	194.1		—		—		194.1		194.1		187.7		—		—		187.7		187.7
Liabilities:
Derivatives	46.2		—		44.8		1.4		46.2		37.6		—		36.8		0.8		37.6
Long-term debt (incl. current maturities)	6,579.8		—		7,768.1		1.7		7,769.8		6,190.2		—		6,917.9		2.0		6,919.9

IPL	June 30, 2020										December 31, 2019
			Fair Value										Fair Value
	Carrying		Level		Level		Level				Carrying		Level		Level		Level
	Amount		1		2		3		Total		Amount		1		2		3		Total
Assets:
Money market fund investments		$198.3		$198.3		$—		$—		$198.3		$5.4		$5.4		$—		$—		$5.4
Derivatives	37.0		—		3.3		33.7		37.0		22.3		—		2.8		19.5		22.3
Deferred proceeds	194.1		—		—		194.1		194.1		187.7		—		—		187.7		187.7
Liabilities:
Derivatives	20.3		—		19.0		1.3		20.3		17.4		—		16.6		0.8		17.4
Long-term debt (incl. current maturities)	3,343.5		—		3,924.7		—		3,924.7		3,147.3		—		3,489.1		—		3,489.1

WPL	June 30, 2020										December 31, 2019
			Fair Value										Fair Value
	Carrying		Level		Level		Level				Carrying		Level		Level		Level
	Amount		1		2		3		Total		Amount		1		2		3		Total
Assets:
Derivatives		$5.4		$—		$1.3		$4.1		$5.4		$4.5		$—		$2.0		$2.5		$4.5
Liabilities:
Derivatives	25.9		—		25.8		0.1		25.9		20.2		—		20.2		—		20.2
Long-term debt (incl. current maturities)	2,129.4		—		2,657.2		—		2,657.2		1,932.7		—		2,268.2		—		2,268.2

Information for Alliant Energy’s and IPL’s fair value measurements using significant unobservable inputs (Level 3 inputs) was as follows (in millions). Such amounts for WPL were not material.

Alliant Energy	Commodity Contract Derivative
	Assets and (Liabilities), net						Deferred Proceeds
Three Months Ended June 30	2020			2019			2020		2019
Beginning balance, April 1		$14.2			$0.4			$188.0		$178.3
Total net gains (losses) included in changes in net assets (realized/unrealized)	12.0			(0.1		)	—		—
Transfers out of Level 3	—			3.9			—		—
Purchases	14.0			13.8			—		—
Sales	(0.1		)	—			—		—
Settlements (a)	(3.7		)	(4.8		)	6.1		36.3
Ending balance, June 30		$36.4			$13.2			$194.1		$214.6
The amount of total net gains for the period included in changes in net assets attributable to the change in unrealized gains relating to assets and liabilities held at June 30		$11.9			$—			$—		$—

Alliant Energy	Commodity Contract Derivative
	Assets and (Liabilities), net						Deferred Proceeds
Six Months Ended June 30	2020			2019			2020		2019
Beginning balance, January 1		$21.2			$12.2			$187.7		$119.4
Total net gains (losses) included in changes in net assets (realized/unrealized)	9.0			(5.7		)	—		—
Transfers out of Level 3	—			3.9			—		—
Purchases	14.0			13.8			—		—
Sales	(0.2		)	(0.2		)	—		—
Settlements (a)	(7.6		)	(10.8		)	6.4		95.2
Ending balance, June 30		$36.4			$13.2			$194.1		$214.6
The amount of total net gains (losses) for the period included in changes in net assets attributable to the change in unrealized gains (losses) relating to assets and liabilities held at June 30		$9.0			($2.6	)		$—		$—

IPL	Commodity Contract Derivative
	Assets and (Liabilities), net						Deferred Proceeds
Three Months Ended June 30	2020			2019			2020		2019
Beginning balance, April 1		$13.5			$0.6			$188.0		$178.3
Total net gains included in changes in net assets (realized/unrealized)	11.0			0.4			—		—
Transfers out of Level 3	—			2.5			—		—
Purchases	10.7			9.5			—		—
Sales	(0.1		)	—			—		—
Settlements (a)	(2.7		)	(3.7		)	6.1		36.3
Ending balance, June 30		$32.4			$9.3			$194.1		$214.6
The amount of total net gains for the period included in changes in net assets attributable to the change in unrealized gains relating to assets and liabilities held at June 30		$11.0			$0.5			$—		$—

IPL	Commodity Contract Derivative
	Assets and (Liabilities), net						Deferred Proceeds
Six Months Ended June 30	2020			2019			2020		2019
Beginning balance, January 1		$18.7			$9.0			$187.7		$119.4
Total net gains (losses) included in changes in net assets (realized/unrealized)	8.8			(2.8		)	—		—
Transfers out of Level 3	—			2.5			—		—
Purchases	10.7			9.5			—		—
Sales	(0.2		)	(0.1		)	—		—
Settlements (a)	(5.6		)	(8.8		)	6.4		95.2
Ending balance, June 30		$32.4			$9.3			$194.1		$214.6
The amount of total net gains (losses) for the period included in changes in net assets attributable to the change in unrealized gains (losses) relating to assets and liabilities held at June 30		$8.8			($0.9	)		$—		$—

(a) Settlements related to deferred proceeds are due to the change in the carrying amount of receivables sold less the allowance for doubtful accounts associated with the receivables sold and cash amounts received from the receivables sold.

Commodity Contracts - The fair value of FTR and natural gas commodity contracts categorized as Level 3 was recognized as net derivative assets as follows (in millions):

	Alliant Energy				IPL				WPL
	Excluding FTRs		FTRs		Excluding FTRs		FTRs		Excluding FTRs		FTRs
June 30, 2020		$19.3		$17.1		$18.6		$13.8		$0.7		$3.3
December 31, 2019	14.6		6.6		13.6		5.1		1.0		1.5

IPL [Member]

Fair Value Measurements

FAIR VALUE MEASUREMENTS

Fair Value of Financial Instruments - The carrying amounts of current assets and current liabilities approximate fair value because of the short maturity of such financial instruments. Carrying amounts and related estimated fair values of other financial instruments were as follows (in millions):

Alliant Energy	June 30, 2020										December 31, 2019
			Fair Value										Fair Value
	Carrying		Level		Level		Level				Carrying		Level		Level		Level
	Amount		1		2		3		Total		Amount		1		2		3		Total
Assets:
Money market fund investments		$198.3		$198.3		$—		$—		$198.3		$5.4		$5.4		$—		$—		$5.4
Derivatives	42.4		—		4.6		37.8		42.4		26.8		—		4.8		22.0		26.8
Deferred proceeds	194.1		—		—		194.1		194.1		187.7		—		—		187.7		187.7
Liabilities:
Derivatives	46.2		—		44.8		1.4		46.2		37.6		—		36.8		0.8		37.6
Long-term debt (incl. current maturities)	6,579.8		—		7,768.1		1.7		7,769.8		6,190.2		—		6,917.9		2.0		6,919.9

IPL	June 30, 2020										December 31, 2019
			Fair Value										Fair Value
	Carrying		Level		Level		Level				Carrying		Level		Level		Level
	Amount		1		2		3		Total		Amount		1		2		3		Total
Assets:
Money market fund investments		$198.3		$198.3		$—		$—		$198.3		$5.4		$5.4		$—		$—		$5.4
Derivatives	37.0		—		3.3		33.7		37.0		22.3		—		2.8		19.5		22.3
Deferred proceeds	194.1		—		—		194.1		194.1		187.7		—		—		187.7		187.7
Liabilities:
Derivatives	20.3		—		19.0		1.3		20.3		17.4		—		16.6		0.8		17.4
Long-term debt (incl. current maturities)	3,343.5		—		3,924.7		—		3,924.7		3,147.3		—		3,489.1		—		3,489.1

WPL	June 30, 2020										December 31, 2019
			Fair Value										Fair Value
	Carrying		Level		Level		Level				Carrying		Level		Level		Level
	Amount		1		2		3		Total		Amount		1		2		3		Total
Assets:
Derivatives		$5.4		$—		$1.3		$4.1		$5.4		$4.5		$—		$2.0		$2.5		$4.5
Liabilities:
Derivatives	25.9		—		25.8		0.1		25.9		20.2		—		20.2		—		20.2
Long-term debt (incl. current maturities)	2,129.4		—		2,657.2		—		2,657.2		1,932.7		—		2,268.2		—		2,268.2

Information for Alliant Energy’s and IPL’s fair value measurements using significant unobservable inputs (Level 3 inputs) was as follows (in millions). Such amounts for WPL were not material.

Alliant Energy	Commodity Contract Derivative
	Assets and (Liabilities), net						Deferred Proceeds
Three Months Ended June 30	2020			2019			2020		2019
Beginning balance, April 1		$14.2			$0.4			$188.0		$178.3
Total net gains (losses) included in changes in net assets (realized/unrealized)	12.0			(0.1		)	—		—
Transfers out of Level 3	—			3.9			—		—
Purchases	14.0			13.8			—		—
Sales	(0.1		)	—			—		—
Settlements (a)	(3.7		)	(4.8		)	6.1		36.3
Ending balance, June 30		$36.4			$13.2			$194.1		$214.6
The amount of total net gains for the period included in changes in net assets attributable to the change in unrealized gains relating to assets and liabilities held at June 30		$11.9			$—			$—		$—

Alliant Energy	Commodity Contract Derivative
	Assets and (Liabilities), net						Deferred Proceeds
Six Months Ended June 30	2020			2019			2020		2019
Beginning balance, January 1		$21.2			$12.2			$187.7		$119.4
Total net gains (losses) included in changes in net assets (realized/unrealized)	9.0			(5.7		)	—		—
Transfers out of Level 3	—			3.9			—		—
Purchases	14.0			13.8			—		—
Sales	(0.2		)	(0.2		)	—		—
Settlements (a)	(7.6		)	(10.8		)	6.4		95.2
Ending balance, June 30		$36.4			$13.2			$194.1		$214.6
The amount of total net gains (losses) for the period included in changes in net assets attributable to the change in unrealized gains (losses) relating to assets and liabilities held at June 30		$9.0			($2.6	)		$—		$—

IPL	Commodity Contract Derivative
	Assets and (Liabilities), net						Deferred Proceeds
Three Months Ended June 30	2020			2019			2020		2019
Beginning balance, April 1		$13.5			$0.6			$188.0		$178.3
Total net gains included in changes in net assets (realized/unrealized)	11.0			0.4			—		—
Transfers out of Level 3	—			2.5			—		—
Purchases	10.7			9.5			—		—
Sales	(0.1		)	—			—		—
Settlements (a)	(2.7		)	(3.7		)	6.1		36.3
Ending balance, June 30		$32.4			$9.3			$194.1		$214.6
The amount of total net gains for the period included in changes in net assets attributable to the change in unrealized gains relating to assets and liabilities held at June 30		$11.0			$0.5			$—		$—

IPL	Commodity Contract Derivative
	Assets and (Liabilities), net						Deferred Proceeds
Six Months Ended June 30	2020			2019			2020		2019
Beginning balance, January 1		$18.7			$9.0			$187.7		$119.4
Total net gains (losses) included in changes in net assets (realized/unrealized)	8.8			(2.8		)	—		—
Transfers out of Level 3	—			2.5			—		—
Purchases	10.7			9.5			—		—
Sales	(0.2		)	(0.1		)	—		—
Settlements (a)	(5.6		)	(8.8		)	6.4		95.2
Ending balance, June 30		$32.4			$9.3			$194.1		$214.6
The amount of total net gains (losses) for the period included in changes in net assets attributable to the change in unrealized gains (losses) relating to assets and liabilities held at June 30		$8.8			($0.9	)		$—		$—

(a) Settlements related to deferred proceeds are due to the change in the carrying amount of receivables sold less the allowance for doubtful accounts associated with the receivables sold and cash amounts received from the receivables sold.

Commodity Contracts - The fair value of FTR and natural gas commodity contracts categorized as Level 3 was recognized as net derivative assets as follows (in millions):

	Alliant Energy				IPL				WPL
	Excluding FTRs		FTRs		Excluding FTRs		FTRs		Excluding FTRs		FTRs
June 30, 2020		$19.3		$17.1		$18.6		$13.8		$0.7		$3.3
December 31, 2019	14.6		6.6		13.6		5.1		1.0		1.5

WPL [Member]

Fair Value Measurements

FAIR VALUE MEASUREMENTS

Fair Value of Financial Instruments - The carrying amounts of current assets and current liabilities approximate fair value because of the short maturity of such financial instruments. Carrying amounts and related estimated fair values of other financial instruments were as follows (in millions):

Alliant Energy	June 30, 2020										December 31, 2019
			Fair Value										Fair Value
	Carrying		Level		Level		Level				Carrying		Level		Level		Level
	Amount		1		2		3		Total		Amount		1		2		3		Total
Assets:
Money market fund investments		$198.3		$198.3		$—		$—		$198.3		$5.4		$5.4		$—		$—		$5.4
Derivatives	42.4		—		4.6		37.8		42.4		26.8		—		4.8		22.0		26.8
Deferred proceeds	194.1		—		—		194.1		194.1		187.7		—		—		187.7		187.7
Liabilities:
Derivatives	46.2		—		44.8		1.4		46.2		37.6		—		36.8		0.8		37.6
Long-term debt (incl. current maturities)	6,579.8		—		7,768.1		1.7		7,769.8		6,190.2		—		6,917.9		2.0		6,919.9

IPL	June 30, 2020										December 31, 2019
			Fair Value										Fair Value
	Carrying		Level		Level		Level				Carrying		Level		Level		Level
	Amount		1		2		3		Total		Amount		1		2		3		Total
Assets:
Money market fund investments		$198.3		$198.3		$—		$—		$198.3		$5.4		$5.4		$—		$—		$5.4
Derivatives	37.0		—		3.3		33.7		37.0		22.3		—		2.8		19.5		22.3
Deferred proceeds	194.1		—		—		194.1		194.1		187.7		—		—		187.7		187.7
Liabilities:
Derivatives	20.3		—		19.0		1.3		20.3		17.4		—		16.6		0.8		17.4
Long-term debt (incl. current maturities)	3,343.5		—		3,924.7		—		3,924.7		3,147.3		—		3,489.1		—		3,489.1

WPL	June 30, 2020										December 31, 2019
			Fair Value										Fair Value
	Carrying		Level		Level		Level				Carrying		Level		Level		Level
	Amount		1		2		3		Total		Amount		1		2		3		Total
Assets:
Derivatives		$5.4		$—		$1.3		$4.1		$5.4		$4.5		$—		$2.0		$2.5		$4.5
Liabilities:
Derivatives	25.9		—		25.8		0.1		25.9		20.2		—		20.2		—		20.2
Long-term debt (incl. current maturities)	2,129.4		—		2,657.2		—		2,657.2		1,932.7		—		2,268.2		—		2,268.2

Information for Alliant Energy’s and IPL’s fair value measurements using significant unobservable inputs (Level 3 inputs) was as follows (in millions). Such amounts for WPL were not material.

Alliant Energy	Commodity Contract Derivative
	Assets and (Liabilities), net						Deferred Proceeds
Three Months Ended June 30	2020			2019			2020		2019
Beginning balance, April 1		$14.2			$0.4			$188.0		$178.3
Total net gains (losses) included in changes in net assets (realized/unrealized)	12.0			(0.1		)	—		—
Transfers out of Level 3	—			3.9			—		—
Purchases	14.0			13.8			—		—
Sales	(0.1		)	—			—		—
Settlements (a)	(3.7		)	(4.8		)	6.1		36.3
Ending balance, June 30		$36.4			$13.2			$194.1		$214.6
The amount of total net gains for the period included in changes in net assets attributable to the change in unrealized gains relating to assets and liabilities held at June 30		$11.9			$—			$—		$—

Alliant Energy	Commodity Contract Derivative
	Assets and (Liabilities), net						Deferred Proceeds
Six Months Ended June 30	2020			2019			2020		2019
Beginning balance, January 1		$21.2			$12.2			$187.7		$119.4
Total net gains (losses) included in changes in net assets (realized/unrealized)	9.0			(5.7		)	—		—
Transfers out of Level 3	—			3.9			—		—
Purchases	14.0			13.8			—		—
Sales	(0.2		)	(0.2		)	—		—
Settlements (a)	(7.6		)	(10.8		)	6.4		95.2
Ending balance, June 30		$36.4			$13.2			$194.1		$214.6
The amount of total net gains (losses) for the period included in changes in net assets attributable to the change in unrealized gains (losses) relating to assets and liabilities held at June 30		$9.0			($2.6	)		$—		$—

IPL	Commodity Contract Derivative
	Assets and (Liabilities), net						Deferred Proceeds
Three Months Ended June 30	2020			2019			2020		2019
Beginning balance, April 1		$13.5			$0.6			$188.0		$178.3
Total net gains included in changes in net assets (realized/unrealized)	11.0			0.4			—		—
Transfers out of Level 3	—			2.5			—		—
Purchases	10.7			9.5			—		—
Sales	(0.1		)	—			—		—
Settlements (a)	(2.7		)	(3.7		)	6.1		36.3
Ending balance, June 30		$32.4			$9.3			$194.1		$214.6
The amount of total net gains for the period included in changes in net assets attributable to the change in unrealized gains relating to assets and liabilities held at June 30		$11.0			$0.5			$—		$—

IPL	Commodity Contract Derivative
	Assets and (Liabilities), net						Deferred Proceeds
Six Months Ended June 30	2020			2019			2020		2019
Beginning balance, January 1		$18.7			$9.0			$187.7		$119.4
Total net gains (losses) included in changes in net assets (realized/unrealized)	8.8			(2.8		)	—		—
Transfers out of Level 3	—			2.5			—		—
Purchases	10.7			9.5			—		—
Sales	(0.2		)	(0.1		)	—		—
Settlements (a)	(5.6		)	(8.8		)	6.4		95.2
Ending balance, June 30		$32.4			$9.3			$194.1		$214.6
The amount of total net gains (losses) for the period included in changes in net assets attributable to the change in unrealized gains (losses) relating to assets and liabilities held at June 30		$8.8			($0.9	)		$—		$—

(a) Settlements related to deferred proceeds are due to the change in the carrying amount of receivables sold less the allowance for doubtful accounts associated with the receivables sold and cash amounts received from the receivables sold.

Commodity Contracts - The fair value of FTR and natural gas commodity contracts categorized as Level 3 was recognized as net derivative assets as follows (in millions):

	Alliant Energy				IPL				WPL
	Excluding FTRs		FTRs		Excluding FTRs		FTRs		Excluding FTRs		FTRs
June 30, 2020		$19.3		$17.1		$18.6		$13.8		$0.7		$3.3
December 31, 2019	14.6		6.6		13.6		5.1		1.0		1.5

XML

Commitments And Contingencies

6 Months Ended

Jun. 30, 2020

Commitments and Contingencies Disclosure

COMMITMENTS AND CONTINGENCIES

NOTE 13(a) Capital Purchase Commitments - Various contractual obligations contain minimum future commitments related to capital expenditures for certain construction projects. IPL’s projects include the expansion of wind generation. WPL’s projects include the expansion of wind and solar generation. At June 30, 2020, Alliant Energy’s, IPL’s and WPL’s minimum future commitments for these projects were $60 million, $8 million and $52 million, respectively.

NOTE 13(b) Other Purchase Commitments - Various commodity supply, transportation and storage contracts help meet obligations to provide electricity and natural gas to utility customers. In addition, there are various purchase commitments associated with other goods and services. At June 30, 2020, the related minimum future commitments were as follows (in millions):

	Alliant Energy		IPL		WPL
Purchased power (a)		$39		$38		$1
Natural gas	1,017		536		481
Coal (b)	101		62		39
Other (c)	113		54		28
		$1,270		$690		$549

(a) Includes payments required by PPAs for capacity rights and minimum quantities of MWhs required to be purchased. As a result of an amendment to shorten the term of the DAEC PPA, Alliant Energy’s and IPL’s amounts include minimum future commitments related to IPL’s purchase of capacity and the resulting energy from DAEC through September 2020, and do not include the September 2020 buyout payment of $110 million.

(b) Corporate Services has historically entered into system-wide coal contracts on behalf of IPL and WPL that include minimum future commitments. Such commitments were assigned to IPL and WPL based on information available as of June 30, 2020 regarding expected future usage, which is subject to change.

(c) Includes individual commitments incurred during the normal course of business that exceeded $1 million at June 30, 2020.

NOTE 13(c) Guarantees and Indemnifications -

Whiting Petroleum - Whiting Petroleum is an independent oil and gas company. In 2004, Alliant Energy sold its remaining interest in Whiting Petroleum. Alliant Energy Resources, LLC, as the successor to a predecessor entity that owned Whiting Petroleum, and a wholly-owned subsidiary of AEF, continues to guarantee the partnership obligations of an affiliate of Whiting Petroleum under multiple general partnership agreements in the oil and gas industry. Based on information made available to Alliant Energy by Whiting Petroleum, the Whiting Petroleum affiliate holds an approximate 6% share in the partnerships and currently known obligations include costs associated with the future abandonment of certain platforms off the coast of California and related onshore plant and equipment owned by the partnerships. The general partnerships were formed under California law, and Alliant Energy Resources, LLC’s guarantees, which do not include a maximum limit, apply to the Whiting Petroleum affiliate’s obligations and to the other partners. Alliant Energy Resources, LLC may be required to perform under the guarantees if the affiliate of Whiting Petroleum is unable to meet its partnership obligations.

As of June 30, 2020, the currently known partnership obligations are the abandonment obligations. The Whiting Petroleum affiliate’s share of these abandonment obligations on an undiscounted basis is estimated at $63 million as of June 30, 2020 based on information made available to Alliant Energy by Whiting Petroleum, and this represents Alliant Energy’s best estimate of the contingent obligations for potential future payments. Alliant Energy is not aware of any material liabilities related to these guarantees that it is probable that it will be obligated to pay; however, the new credit loss accounting standard adopted on January 1, 2020 requires recognition of a liability for expected credit losses related to the contingent obligations that are in the scope of these guarantees. With the adoption of this standard, Alliant Energy recorded a pre-tax $12 million cumulative effect adjustment to decrease the opening balance of retained earnings as of January 1, 2020. As a result of Whiting Petroleum’s deterioration in credit worthiness since January 1, 2020 likely from significantly depressed oil and gas prices and general market conditions, Alliant Energy currently expects credit exposure related to the guarantees and has recognized a $20 million credit loss liability as of June 30, 2020 related to the contingent obligations, which is recorded in

“Other liabilities” on Alliant Energy’s balance sheet. The incremental pre-tax change in the liability, $8 million, was recorded as a credit loss expense within Alliant Energy’s “Other operation and maintenance” expenses for the six months ended June 30, 2020. There was no incremental pre-tax change in the liability recorded for the three months ended June 30, 2020.

Non-utility Wind Farm in Oklahoma - In 2017, a wholly-owned subsidiary of AEF acquired a cash equity ownership interest in a non-utility wind farm located in Oklahoma. The wind farm provides electricity to a third-party under a long-term PPA. Alliant Energy provided a parent guarantee of its subsidiary’s indemnification obligations under the related operating agreement and PPA. Alliant Energy’s obligations under the operating agreement were $82 million as of June 30, 2020 and will reduce annually until expiring in July 2047. Alliant Energy’s obligations under the PPA are subject to a maximum limit of $17 million and expire in December 2031, subject to potential extension. Alliant Energy is not aware of any material liabilities related to this guarantee that it is probable that it will be obligated to pay and therefore has not recognized any material liabilities related to this guarantee as of June 30, 2020 and December 31, 2019.

IPL’s Minnesota Electric Distribution Assets - IPL provided indemnifications associated with the 2015 sale of its Minnesota electric distribution assets for losses resulting from potential breach of IPL’s representations, warranties and obligations under the sale agreement. Alliant Energy and IPL believe the likelihood of having to make any material cash payments under these indemnifications is remote. IPL has not recorded any material liabilities related to these indemnifications as of June 30, 2020 and December 31, 2019. The general terms of the indemnifications provided by IPL included a maximum limit of $17 million and expire in October 2020.

NOTE 13(d) Environmental Matters -

Manufactured Gas Plant (MGP) Sites - IPL and WPL have current or previous ownership interests in various sites that are previously associated with the production of gas for which IPL and WPL have, or may have in the future, liability for investigation, remediation and monitoring costs. IPL and WPL are working pursuant to the requirements of various federal and state agencies to investigate, mitigate, prevent and remediate, where necessary, the environmental impacts to property, including natural resources, at and around these former MGP sites in order to protect public health and the environment. At June 30, 2020, estimated future costs expected to be incurred for the investigation, remediation and monitoring of the MGP sites, as well as environmental liabilities recorded on the balance sheets for these sites, which are not discounted, were as follows (in millions). At June 30, 2020, such amounts for WPL were not material.

	Alliant Energy				IPL
Range of estimated future costs		$12	-	$29		$10	-	$24
Current and non-current environmental liabilities	16				13

IPL Consent Decree - In 2015, the U.S. District Court for the Northern District of Iowa approved a Consent Decree that IPL entered into with the EPA, the Sierra Club, the State of Iowa and Linn County in Iowa, thereby resolving potential Clean Air Act issues associated with emissions from IPL’s coal-fired generating facilities in Iowa. IPL has completed various requirements under the Consent Decree. IPL’s remaining requirements include fuel switching or retiring Burlington by December 31, 2021 and Prairie Creek Units 1 and 3 by December 31, 2025. Alliant Energy and IPL currently expect to recover material costs incurred by IPL related to compliance with the terms of the Consent Decree from IPL’s electric customers.

Other Environmental Contingencies - In addition to the environmental liabilities discussed above, various environmental rules are monitored that may have a significant impact on future operations. Several of these environmental rules are subject to legal challenges, reconsideration and/or other uncertainties. Given uncertainties regarding the outcome, timing and compliance plans for these environmental matters, the complete financial impact of each of these rules is not able to be determined; however, future capital investments and/or modifications to EGUs to comply with certain of these rules could be significant. Specific current, proposed or potential environmental matters include, among others: Effluent Limitation Guidelines, Coal Combustion Residuals Rule, and various legislation and EPA regulations to monitor and regulate the emission of greenhouse gases, including the Clean Air Act.

NOTE 13(e) Collective Bargaining Agreements - At June 30, 2020, employees covered by collective bargaining agreements represented 53%, 60% and 82% of total employees of Alliant Energy, IPL and WPL, respectively. On August 31, 2020, IPL’s collective bargaining agreement with International Brotherhood of Electrical Workers Local 204 (Cedar Rapids) expires, representing 18% and 44% of total employees of Alliant Energy and IPL, respectively. While the process to renew the agreement is underway and a tentative agreement has been reached, Alliant Energy and IPL are unable to predict the outcome.

NOTE 13(f) MISO Transmission Owner Return on Equity Complaints - A group of MISO cooperative and municipal utilities previously filed complaints with FERC requesting a reduction to the base return on equity used by MISO transmission owners, including ITC Midwest LLC and ATC. The first complaint covered the period from November 12, 2013 through February 11, 2015. In 2017, IPL and WPL received refunds related to the first complaint period, which were subsequently refunded to their retail and wholesale customers. The second complaint covered the period from February 12, 2015 through May 11, 2016. In November 2019, FERC issued an order on the previously filed complaints and reduced the base return on equity used by the MISO transmission owners to 9.88% effective for the first complaint period and subsequent to September 28, 2016. The November 2019 FERC order also dismissed the second complaint; therefore, FERC did not direct refunds to be made for that complaint. In May 2020, FERC issued an order in response to various rehearing requests and increased the base return on equity used by the MISO transmission owners from 9.88% to 10.02% for the first complaint period and subsequent to September 28, 2016, which reduces the refunds originally anticipated to be received by IPL and WPL as a result of FERC’s November 2019 order.

In the second quarter of 2020, IPL and WPL received $10 million and $3 million, respectively, in refunds related to the November 2019 FERC order. Additional refunds are currently expected to be issued; however, as a result of the May 2020 FERC order, timing is uncertain. IPL currently expects that all refunds will be returned to its retail electric customers after refund amounts and timing are known and a refund plan is approved by the IUB. WPL proposed to retain the refunds as part of WPL’s application with the PSCW to maintain its current retail electric base rates through the end of 2021. WPL currently expects that any refunds not utilized to maintain base rates would be returned to its customers in WPL’s next retail electric rate review proceeding. Any further changes in FERC’s decisions may have an impact on Alliant Energy’s share of ATC’s future earnings and customer costs.

IPL [Member]

Commitments and Contingencies Disclosure

COMMITMENTS AND CONTINGENCIES

NOTE 13(a) Capital Purchase Commitments - Various contractual obligations contain minimum future commitments related to capital expenditures for certain construction projects. IPL’s projects include the expansion of wind generation. WPL’s projects include the expansion of wind and solar generation. At June 30, 2020, Alliant Energy’s, IPL’s and WPL’s minimum future commitments for these projects were $60 million, $8 million and $52 million, respectively.

NOTE 13(b) Other Purchase Commitments - Various commodity supply, transportation and storage contracts help meet obligations to provide electricity and natural gas to utility customers. In addition, there are various purchase commitments associated with other goods and services. At June 30, 2020, the related minimum future commitments were as follows (in millions):

	Alliant Energy		IPL		WPL
Purchased power (a)		$39		$38		$1
Natural gas	1,017		536		481
Coal (b)	101		62		39
Other (c)	113		54		28
		$1,270		$690		$549

(a) Includes payments required by PPAs for capacity rights and minimum quantities of MWhs required to be purchased. As a result of an amendment to shorten the term of the DAEC PPA, Alliant Energy’s and IPL’s amounts include minimum future commitments related to IPL’s purchase of capacity and the resulting energy from DAEC through September 2020, and do not include the September 2020 buyout payment of $110 million.

(b) Corporate Services has historically entered into system-wide coal contracts on behalf of IPL and WPL that include minimum future commitments. Such commitments were assigned to IPL and WPL based on information available as of June 30, 2020 regarding expected future usage, which is subject to change.

(c) Includes individual commitments incurred during the normal course of business that exceeded $1 million at June 30, 2020.

NOTE 13(c) Guarantees and Indemnifications -

Whiting Petroleum - Whiting Petroleum is an independent oil and gas company. In 2004, Alliant Energy sold its remaining interest in Whiting Petroleum. Alliant Energy Resources, LLC, as the successor to a predecessor entity that owned Whiting Petroleum, and a wholly-owned subsidiary of AEF, continues to guarantee the partnership obligations of an affiliate of Whiting Petroleum under multiple general partnership agreements in the oil and gas industry. Based on information made available to Alliant Energy by Whiting Petroleum, the Whiting Petroleum affiliate holds an approximate 6% share in the partnerships and currently known obligations include costs associated with the future abandonment of certain platforms off the coast of California and related onshore plant and equipment owned by the partnerships. The general partnerships were formed under California law, and Alliant Energy Resources, LLC’s guarantees, which do not include a maximum limit, apply to the Whiting Petroleum affiliate’s obligations and to the other partners. Alliant Energy Resources, LLC may be required to perform under the guarantees if the affiliate of Whiting Petroleum is unable to meet its partnership obligations.

As of June 30, 2020, the currently known partnership obligations are the abandonment obligations. The Whiting Petroleum affiliate’s share of these abandonment obligations on an undiscounted basis is estimated at $63 million as of June 30, 2020 based on information made available to Alliant Energy by Whiting Petroleum, and this represents Alliant Energy’s best estimate of the contingent obligations for potential future payments. Alliant Energy is not aware of any material liabilities related to these guarantees that it is probable that it will be obligated to pay; however, the new credit loss accounting standard adopted on January 1, 2020 requires recognition of a liability for expected credit losses related to the contingent obligations that are in the scope of these guarantees. With the adoption of this standard, Alliant Energy recorded a pre-tax $12 million cumulative effect adjustment to decrease the opening balance of retained earnings as of January 1, 2020. As a result of Whiting Petroleum’s deterioration in credit worthiness since January 1, 2020 likely from significantly depressed oil and gas prices and general market conditions, Alliant Energy currently expects credit exposure related to the guarantees and has recognized a $20 million credit loss liability as of June 30, 2020 related to the contingent obligations, which is recorded in

“Other liabilities” on Alliant Energy’s balance sheet. The incremental pre-tax change in the liability, $8 million, was recorded as a credit loss expense within Alliant Energy’s “Other operation and maintenance” expenses for the six months ended June 30, 2020. There was no incremental pre-tax change in the liability recorded for the three months ended June 30, 2020.

Non-utility Wind Farm in Oklahoma - In 2017, a wholly-owned subsidiary of AEF acquired a cash equity ownership interest in a non-utility wind farm located in Oklahoma. The wind farm provides electricity to a third-party under a long-term PPA. Alliant Energy provided a parent guarantee of its subsidiary’s indemnification obligations under the related operating agreement and PPA. Alliant Energy’s obligations under the operating agreement were $82 million as of June 30, 2020 and will reduce annually until expiring in July 2047. Alliant Energy’s obligations under the PPA are subject to a maximum limit of $17 million and expire in December 2031, subject to potential extension. Alliant Energy is not aware of any material liabilities related to this guarantee that it is probable that it will be obligated to pay and therefore has not recognized any material liabilities related to this guarantee as of June 30, 2020 and December 31, 2019.

IPL’s Minnesota Electric Distribution Assets - IPL provided indemnifications associated with the 2015 sale of its Minnesota electric distribution assets for losses resulting from potential breach of IPL’s representations, warranties and obligations under the sale agreement. Alliant Energy and IPL believe the likelihood of having to make any material cash payments under these indemnifications is remote. IPL has not recorded any material liabilities related to these indemnifications as of June 30, 2020 and December 31, 2019. The general terms of the indemnifications provided by IPL included a maximum limit of $17 million and expire in October 2020.

NOTE 13(d) Environmental Matters -

Manufactured Gas Plant (MGP) Sites - IPL and WPL have current or previous ownership interests in various sites that are previously associated with the production of gas for which IPL and WPL have, or may have in the future, liability for investigation, remediation and monitoring costs. IPL and WPL are working pursuant to the requirements of various federal and state agencies to investigate, mitigate, prevent and remediate, where necessary, the environmental impacts to property, including natural resources, at and around these former MGP sites in order to protect public health and the environment. At June 30, 2020, estimated future costs expected to be incurred for the investigation, remediation and monitoring of the MGP sites, as well as environmental liabilities recorded on the balance sheets for these sites, which are not discounted, were as follows (in millions). At June 30, 2020, such amounts for WPL were not material.

	Alliant Energy				IPL
Range of estimated future costs		$12	-	$29		$10	-	$24
Current and non-current environmental liabilities	16				13

IPL Consent Decree - In 2015, the U.S. District Court for the Northern District of Iowa approved a Consent Decree that IPL entered into with the EPA, the Sierra Club, the State of Iowa and Linn County in Iowa, thereby resolving potential Clean Air Act issues associated with emissions from IPL’s coal-fired generating facilities in Iowa. IPL has completed various requirements under the Consent Decree. IPL’s remaining requirements include fuel switching or retiring Burlington by December 31, 2021 and Prairie Creek Units 1 and 3 by December 31, 2025. Alliant Energy and IPL currently expect to recover material costs incurred by IPL related to compliance with the terms of the Consent Decree from IPL’s electric customers.

Other Environmental Contingencies - In addition to the environmental liabilities discussed above, various environmental rules are monitored that may have a significant impact on future operations. Several of these environmental rules are subject to legal challenges, reconsideration and/or other uncertainties. Given uncertainties regarding the outcome, timing and compliance plans for these environmental matters, the complete financial impact of each of these rules is not able to be determined; however, future capital investments and/or modifications to EGUs to comply with certain of these rules could be significant. Specific current, proposed or potential environmental matters include, among others: Effluent Limitation Guidelines, Coal Combustion Residuals Rule, and various legislation and EPA regulations to monitor and regulate the emission of greenhouse gases, including the Clean Air Act.

NOTE 13(e) Collective Bargaining Agreements - At June 30, 2020, employees covered by collective bargaining agreements represented 53%, 60% and 82% of total employees of Alliant Energy, IPL and WPL, respectively. On August 31, 2020, IPL’s collective bargaining agreement with International Brotherhood of Electrical Workers Local 204 (Cedar Rapids) expires, representing 18% and 44% of total employees of Alliant Energy and IPL, respectively. While the process to renew the agreement is underway and a tentative agreement has been reached, Alliant Energy and IPL are unable to predict the outcome.

NOTE 13(f) MISO Transmission Owner Return on Equity Complaints - A group of MISO cooperative and municipal utilities previously filed complaints with FERC requesting a reduction to the base return on equity used by MISO transmission owners, including ITC Midwest LLC and ATC. The first complaint covered the period from November 12, 2013 through February 11, 2015. In 2017, IPL and WPL received refunds related to the first complaint period, which were subsequently refunded to their retail and wholesale customers. The second complaint covered the period from February 12, 2015 through May 11, 2016. In November 2019, FERC issued an order on the previously filed complaints and reduced the base return on equity used by the MISO transmission owners to 9.88% effective for the first complaint period and subsequent to September 28, 2016. The November 2019 FERC order also dismissed the second complaint; therefore, FERC did not direct refunds to be made for that complaint. In May 2020, FERC issued an order in response to various rehearing requests and increased the base return on equity used by the MISO transmission owners from 9.88% to 10.02% for the first complaint period and subsequent to September 28, 2016, which reduces the refunds originally anticipated to be received by IPL and WPL as a result of FERC’s November 2019 order.

In the second quarter of 2020, IPL and WPL received $10 million and $3 million, respectively, in refunds related to the November 2019 FERC order. Additional refunds are currently expected to be issued; however, as a result of the May 2020 FERC order, timing is uncertain. IPL currently expects that all refunds will be returned to its retail electric customers after refund amounts and timing are known and a refund plan is approved by the IUB. WPL proposed to retain the refunds as part of WPL’s application with the PSCW to maintain its current retail electric base rates through the end of 2021. WPL currently expects that any refunds not utilized to maintain base rates would be returned to its customers in WPL’s next retail electric rate review proceeding. Any further changes in FERC’s decisions may have an impact on Alliant Energy’s share of ATC’s future earnings and customer costs.

WPL [Member]

Commitments and Contingencies Disclosure

COMMITMENTS AND CONTINGENCIES

NOTE 13(a) Capital Purchase Commitments - Various contractual obligations contain minimum future commitments related to capital expenditures for certain construction projects. IPL’s projects include the expansion of wind generation. WPL’s projects include the expansion of wind and solar generation. At June 30, 2020, Alliant Energy’s, IPL’s and WPL’s minimum future commitments for these projects were $60 million, $8 million and $52 million, respectively.

NOTE 13(b) Other Purchase Commitments - Various commodity supply, transportation and storage contracts help meet obligations to provide electricity and natural gas to utility customers. In addition, there are various purchase commitments associated with other goods and services. At June 30, 2020, the related minimum future commitments were as follows (in millions):

	Alliant Energy		IPL		WPL
Purchased power (a)		$39		$38		$1
Natural gas	1,017		536		481
Coal (b)	101		62		39
Other (c)	113		54		28
		$1,270		$690		$549

(a) Includes payments required by PPAs for capacity rights and minimum quantities of MWhs required to be purchased. As a result of an amendment to shorten the term of the DAEC PPA, Alliant Energy’s and IPL’s amounts include minimum future commitments related to IPL’s purchase of capacity and the resulting energy from DAEC through September 2020, and do not include the September 2020 buyout payment of $110 million.

(b) Corporate Services has historically entered into system-wide coal contracts on behalf of IPL and WPL that include minimum future commitments. Such commitments were assigned to IPL and WPL based on information available as of June 30, 2020 regarding expected future usage, which is subject to change.

(c) Includes individual commitments incurred during the normal course of business that exceeded $1 million at June 30, 2020.

NOTE 13(c) Guarantees and Indemnifications -

Whiting Petroleum - Whiting Petroleum is an independent oil and gas company. In 2004, Alliant Energy sold its remaining interest in Whiting Petroleum. Alliant Energy Resources, LLC, as the successor to a predecessor entity that owned Whiting Petroleum, and a wholly-owned subsidiary of AEF, continues to guarantee the partnership obligations of an affiliate of Whiting Petroleum under multiple general partnership agreements in the oil and gas industry. Based on information made available to Alliant Energy by Whiting Petroleum, the Whiting Petroleum affiliate holds an approximate 6% share in the partnerships and currently known obligations include costs associated with the future abandonment of certain platforms off the coast of California and related onshore plant and equipment owned by the partnerships. The general partnerships were formed under California law, and Alliant Energy Resources, LLC’s guarantees, which do not include a maximum limit, apply to the Whiting Petroleum affiliate’s obligations and to the other partners. Alliant Energy Resources, LLC may be required to perform under the guarantees if the affiliate of Whiting Petroleum is unable to meet its partnership obligations.

As of June 30, 2020, the currently known partnership obligations are the abandonment obligations. The Whiting Petroleum affiliate’s share of these abandonment obligations on an undiscounted basis is estimated at $63 million as of June 30, 2020 based on information made available to Alliant Energy by Whiting Petroleum, and this represents Alliant Energy’s best estimate of the contingent obligations for potential future payments. Alliant Energy is not aware of any material liabilities related to these guarantees that it is probable that it will be obligated to pay; however, the new credit loss accounting standard adopted on January 1, 2020 requires recognition of a liability for expected credit losses related to the contingent obligations that are in the scope of these guarantees. With the adoption of this standard, Alliant Energy recorded a pre-tax $12 million cumulative effect adjustment to decrease the opening balance of retained earnings as of January 1, 2020. As a result of Whiting Petroleum’s deterioration in credit worthiness since January 1, 2020 likely from significantly depressed oil and gas prices and general market conditions, Alliant Energy currently expects credit exposure related to the guarantees and has recognized a $20 million credit loss liability as of June 30, 2020 related to the contingent obligations, which is recorded in

“Other liabilities” on Alliant Energy’s balance sheet. The incremental pre-tax change in the liability, $8 million, was recorded as a credit loss expense within Alliant Energy’s “Other operation and maintenance” expenses for the six months ended June 30, 2020. There was no incremental pre-tax change in the liability recorded for the three months ended June 30, 2020.

Non-utility Wind Farm in Oklahoma - In 2017, a wholly-owned subsidiary of AEF acquired a cash equity ownership interest in a non-utility wind farm located in Oklahoma. The wind farm provides electricity to a third-party under a long-term PPA. Alliant Energy provided a parent guarantee of its subsidiary’s indemnification obligations under the related operating agreement and PPA. Alliant Energy’s obligations under the operating agreement were $82 million as of June 30, 2020 and will reduce annually until expiring in July 2047. Alliant Energy’s obligations under the PPA are subject to a maximum limit of $17 million and expire in December 2031, subject to potential extension. Alliant Energy is not aware of any material liabilities related to this guarantee that it is probable that it will be obligated to pay and therefore has not recognized any material liabilities related to this guarantee as of June 30, 2020 and December 31, 2019.

IPL’s Minnesota Electric Distribution Assets - IPL provided indemnifications associated with the 2015 sale of its Minnesota electric distribution assets for losses resulting from potential breach of IPL’s representations, warranties and obligations under the sale agreement. Alliant Energy and IPL believe the likelihood of having to make any material cash payments under these indemnifications is remote. IPL has not recorded any material liabilities related to these indemnifications as of June 30, 2020 and December 31, 2019. The general terms of the indemnifications provided by IPL included a maximum limit of $17 million and expire in October 2020.

NOTE 13(d) Environmental Matters -

Manufactured Gas Plant (MGP) Sites - IPL and WPL have current or previous ownership interests in various sites that are previously associated with the production of gas for which IPL and WPL have, or may have in the future, liability for investigation, remediation and monitoring costs. IPL and WPL are working pursuant to the requirements of various federal and state agencies to investigate, mitigate, prevent and remediate, where necessary, the environmental impacts to property, including natural resources, at and around these former MGP sites in order to protect public health and the environment. At June 30, 2020, estimated future costs expected to be incurred for the investigation, remediation and monitoring of the MGP sites, as well as environmental liabilities recorded on the balance sheets for these sites, which are not discounted, were as follows (in millions). At June 30, 2020, such amounts for WPL were not material.

	Alliant Energy				IPL
Range of estimated future costs		$12	-	$29		$10	-	$24
Current and non-current environmental liabilities	16				13

IPL Consent Decree - In 2015, the U.S. District Court for the Northern District of Iowa approved a Consent Decree that IPL entered into with the EPA, the Sierra Club, the State of Iowa and Linn County in Iowa, thereby resolving potential Clean Air Act issues associated with emissions from IPL’s coal-fired generating facilities in Iowa. IPL has completed various requirements under the Consent Decree. IPL’s remaining requirements include fuel switching or retiring Burlington by December 31, 2021 and Prairie Creek Units 1 and 3 by December 31, 2025. Alliant Energy and IPL currently expect to recover material costs incurred by IPL related to compliance with the terms of the Consent Decree from IPL’s electric customers.

Other Environmental Contingencies - In addition to the environmental liabilities discussed above, various environmental rules are monitored that may have a significant impact on future operations. Several of these environmental rules are subject to legal challenges, reconsideration and/or other uncertainties. Given uncertainties regarding the outcome, timing and compliance plans for these environmental matters, the complete financial impact of each of these rules is not able to be determined; however, future capital investments and/or modifications to EGUs to comply with certain of these rules could be significant. Specific current, proposed or potential environmental matters include, among others: Effluent Limitation Guidelines, Coal Combustion Residuals Rule, and various legislation and EPA regulations to monitor and regulate the emission of greenhouse gases, including the Clean Air Act.

NOTE 13(e) Collective Bargaining Agreements - At June 30, 2020, employees covered by collective bargaining agreements represented 53%, 60% and 82% of total employees of Alliant Energy, IPL and WPL, respectively. On August 31, 2020, IPL’s collective bargaining agreement with International Brotherhood of Electrical Workers Local 204 (Cedar Rapids) expires, representing 18% and 44% of total employees of Alliant Energy and IPL, respectively. While the process to renew the agreement is underway and a tentative agreement has been reached, Alliant Energy and IPL are unable to predict the outcome.

NOTE 13(f) MISO Transmission Owner Return on Equity Complaints - A group of MISO cooperative and municipal utilities previously filed complaints with FERC requesting a reduction to the base return on equity used by MISO transmission owners, including ITC Midwest LLC and ATC. The first complaint covered the period from November 12, 2013 through February 11, 2015. In 2017, IPL and WPL received refunds related to the first complaint period, which were subsequently refunded to their retail and wholesale customers. The second complaint covered the period from February 12, 2015 through May 11, 2016. In November 2019, FERC issued an order on the previously filed complaints and reduced the base return on equity used by the MISO transmission owners to 9.88% effective for the first complaint period and subsequent to September 28, 2016. The November 2019 FERC order also dismissed the second complaint; therefore, FERC did not direct refunds to be made for that complaint. In May 2020, FERC issued an order in response to various rehearing requests and increased the base return on equity used by the MISO transmission owners from 9.88% to 10.02% for the first complaint period and subsequent to September 28, 2016, which reduces the refunds originally anticipated to be received by IPL and WPL as a result of FERC’s November 2019 order.

In the second quarter of 2020, IPL and WPL received $10 million and $3 million, respectively, in refunds related to the November 2019 FERC order. Additional refunds are currently expected to be issued; however, as a result of the May 2020 FERC order, timing is uncertain. IPL currently expects that all refunds will be returned to its retail electric customers after refund amounts and timing are known and a refund plan is approved by the IUB. WPL proposed to retain the refunds as part of WPL’s application with the PSCW to maintain its current retail electric base rates through the end of 2021. WPL currently expects that any refunds not utilized to maintain base rates would be returned to its customers in WPL’s next retail electric rate review proceeding. Any further changes in FERC’s decisions may have an impact on Alliant Energy’s share of ATC’s future earnings and customer costs.

XML

Segments Of Business

6 Months Ended

Jun. 30, 2020

Segment Reporting Information [Line Items]

Segments Of Business

SEGMENTS OF BUSINESS

Certain financial information relating to Alliant Energy’s, IPL’s and WPL’s business segments is as follows. Intersegment revenues were not material to their respective operations.

Alliant Energy									ATC Holdings,		Alliant
	Utility								Non-Utility,		Energy
	Electric		Gas		Other		Total		Parent and Other		Consolidated
	(in millions)
Three Months Ended June 30, 2020
Revenues		$675.2		$58.9		$10.1		$744.2		$18.9		$763.1
Operating income	152.1		7.1		1.2		160.4		7.7		168.1
Net income attributable to Alliant Energy common shareowners							117.4		17.0		134.4
Three Months Ended June 30, 2019
Revenues		$691.2		$65.2		$10.9		$767.3		$22.9		$790.2
Operating income	132.9		7.2		1.4		141.5		8.3		149.8
Net income attributable to Alliant Energy common shareowners							87.0		7.6		94.6

Alliant Energy									ATC Holdings,		Alliant
	Utility								Non-Utility,		Energy
	Electric		Gas		Other		Total		Parent and Other		Consolidated
	(in millions)
Six Months Ended June 30, 2020
Revenues		$1,405.5		$211.1		$21.7		$1,638.3		$40.5		$1,678.8
Operating income	298.3		48.7		3.9		350.9		5.5		356.4
Net income attributable to Alliant Energy common shareowners							289.6		14.8		304.4
Six Months Ended June 30, 2019
Revenues		$1,434.6		$281.0		$22.0		$1,737.6		$39.8		$1,777.4
Operating income	259.3		52.4		1.4		313.1		13.5		326.6
Net income attributable to Alliant Energy common shareowners							206.0		13.7		219.7

IPL	Electric		Gas		Other		Total
	(in millions)
Three Months Ended June 30, 2020
Revenues		$388.4		$33.9		$9.6		$431.9
Operating income	82.1		5.2		1.4		88.7
Net income available for common stock							59.8
Three Months Ended June 30, 2019
Revenues		$392.3		$38.4		$10.5		$441.2
Operating income	68.9		4.2		1.4		74.5
Net income available for common stock							45.0
Six Months Ended June 30, 2020
Revenues		$813.2		$116.9		$20.7		$950.8
Operating income	149.1		32.5		3.8		185.4
Net income available for common stock							142.4
Six Months Ended June 30, 2019
Revenues		$812.1		$163.0		$21.2		$996.3
Operating income	115.7		30.5		1.8		148.0
Net income available for common stock							98.3

WPL	Electric		Gas		Other			Total
	(in millions)
Three Months Ended June 30, 2020
Revenues		$286.8		$25.0		$0.5			$312.3
Operating income (loss)	70.0		1.9		(0.2		)	71.7
Net income								57.6
Three Months Ended June 30, 2019
Revenues		$298.9		$26.8		$0.4			$326.1
Operating income	64.0		3.0		—			67.0
Net income								42.0
Six Months Ended June 30, 2020
Revenues		$592.3		$94.2		$1.0			$687.5
Operating income	149.2		16.2		0.1			165.5
Net income								147.2
Six Months Ended June 30, 2019
Revenues		$622.5		$118.0		$0.8			$741.3
Operating income (loss)	143.6		21.9		(0.4		)	165.1
Net income								107.7

IPL [Member]

Segment Reporting Information [Line Items]

Segments Of Business

Certain financial information relating to Alliant Energy’s, IPL’s and WPL’s business segments is as follows. Intersegment revenues were not material to their respective operations.

Alliant Energy									ATC Holdings,		Alliant
	Utility								Non-Utility,		Energy
	Electric		Gas		Other		Total		Parent and Other		Consolidated
	(in millions)
Three Months Ended June 30, 2020
Revenues		$675.2		$58.9		$10.1		$744.2		$18.9		$763.1
Operating income	152.1		7.1		1.2		160.4		7.7		168.1
Net income attributable to Alliant Energy common shareowners							117.4		17.0		134.4
Three Months Ended June 30, 2019
Revenues		$691.2		$65.2		$10.9		$767.3		$22.9		$790.2
Operating income	132.9		7.2		1.4		141.5		8.3		149.8
Net income attributable to Alliant Energy common shareowners							87.0		7.6		94.6

Alliant Energy									ATC Holdings,		Alliant
	Utility								Non-Utility,		Energy
	Electric		Gas		Other		Total		Parent and Other		Consolidated
	(in millions)
Six Months Ended June 30, 2020
Revenues		$1,405.5		$211.1		$21.7		$1,638.3		$40.5		$1,678.8
Operating income	298.3		48.7		3.9		350.9		5.5		356.4
Net income attributable to Alliant Energy common shareowners							289.6		14.8		304.4
Six Months Ended June 30, 2019
Revenues		$1,434.6		$281.0		$22.0		$1,737.6		$39.8		$1,777.4
Operating income	259.3		52.4		1.4		313.1		13.5		326.6
Net income attributable to Alliant Energy common shareowners							206.0		13.7		219.7

IPL	Electric		Gas		Other		Total
	(in millions)
Three Months Ended June 30, 2020
Revenues		$388.4		$33.9		$9.6		$431.9
Operating income	82.1		5.2		1.4		88.7
Net income available for common stock							59.8
Three Months Ended June 30, 2019
Revenues		$392.3		$38.4		$10.5		$441.2
Operating income	68.9		4.2		1.4		74.5
Net income available for common stock							45.0
Six Months Ended June 30, 2020
Revenues		$813.2		$116.9		$20.7		$950.8
Operating income	149.1		32.5		3.8		185.4
Net income available for common stock							142.4
Six Months Ended June 30, 2019
Revenues		$812.1		$163.0		$21.2		$996.3
Operating income	115.7		30.5		1.8		148.0
Net income available for common stock							98.3

WPL	Electric		Gas		Other			Total
	(in millions)
Three Months Ended June 30, 2020
Revenues		$286.8		$25.0		$0.5			$312.3
Operating income (loss)	70.0		1.9		(0.2		)	71.7
Net income								57.6
Three Months Ended June 30, 2019
Revenues		$298.9		$26.8		$0.4			$326.1
Operating income	64.0		3.0		—			67.0
Net income								42.0
Six Months Ended June 30, 2020
Revenues		$592.3		$94.2		$1.0			$687.5
Operating income	149.2		16.2		0.1			165.5
Net income								147.2
Six Months Ended June 30, 2019
Revenues		$622.5		$118.0		$0.8			$741.3
Operating income (loss)	143.6		21.9		(0.4		)	165.1
Net income								107.7

WPL [Member]

Segment Reporting Information [Line Items]

Segments Of Business

Certain financial information relating to Alliant Energy’s, IPL’s and WPL’s business segments is as follows. Intersegment revenues were not material to their respective operations.

Alliant Energy									ATC Holdings,		Alliant
	Utility								Non-Utility,		Energy
	Electric		Gas		Other		Total		Parent and Other		Consolidated
	(in millions)
Three Months Ended June 30, 2020
Revenues		$675.2		$58.9		$10.1		$744.2		$18.9		$763.1
Operating income	152.1		7.1		1.2		160.4		7.7		168.1
Net income attributable to Alliant Energy common shareowners							117.4		17.0		134.4
Three Months Ended June 30, 2019
Revenues		$691.2		$65.2		$10.9		$767.3		$22.9		$790.2
Operating income	132.9		7.2		1.4		141.5		8.3		149.8
Net income attributable to Alliant Energy common shareowners							87.0		7.6		94.6

Alliant Energy									ATC Holdings,		Alliant
	Utility								Non-Utility,		Energy
	Electric		Gas		Other		Total		Parent and Other		Consolidated
	(in millions)
Six Months Ended June 30, 2020
Revenues		$1,405.5		$211.1		$21.7		$1,638.3		$40.5		$1,678.8
Operating income	298.3		48.7		3.9		350.9		5.5		356.4
Net income attributable to Alliant Energy common shareowners							289.6		14.8		304.4
Six Months Ended June 30, 2019
Revenues		$1,434.6		$281.0		$22.0		$1,737.6		$39.8		$1,777.4
Operating income	259.3		52.4		1.4		313.1		13.5		326.6
Net income attributable to Alliant Energy common shareowners							206.0		13.7		219.7

IPL	Electric		Gas		Other		Total
	(in millions)
Three Months Ended June 30, 2020
Revenues		$388.4		$33.9		$9.6		$431.9
Operating income	82.1		5.2		1.4		88.7
Net income available for common stock							59.8
Three Months Ended June 30, 2019
Revenues		$392.3		$38.4		$10.5		$441.2
Operating income	68.9		4.2		1.4		74.5
Net income available for common stock							45.0
Six Months Ended June 30, 2020
Revenues		$813.2		$116.9		$20.7		$950.8
Operating income	149.1		32.5		3.8		185.4
Net income available for common stock							142.4
Six Months Ended June 30, 2019
Revenues		$812.1		$163.0		$21.2		$996.3
Operating income	115.7		30.5		1.8		148.0
Net income available for common stock							98.3

WPL	Electric		Gas		Other			Total
	(in millions)
Three Months Ended June 30, 2020
Revenues		$286.8		$25.0		$0.5			$312.3
Operating income (loss)	70.0		1.9		(0.2		)	71.7
Net income								57.6
Three Months Ended June 30, 2019
Revenues		$298.9		$26.8		$0.4			$326.1
Operating income	64.0		3.0		—			67.0
Net income								42.0
Six Months Ended June 30, 2020
Revenues		$592.3		$94.2		$1.0			$687.5
Operating income	149.2		16.2		0.1			165.5
Net income								147.2
Six Months Ended June 30, 2019
Revenues		$622.5		$118.0		$0.8			$741.3
Operating income (loss)	143.6		21.9		(0.4		)	165.1
Net income								107.7

XML

Related Parties

6 Months Ended

Jun. 30, 2020

Related Party Transactions [Line Items]

Related Parties

RELATED PARTIES

Service Agreements - Pursuant to service agreements, IPL and WPL receive various administrative and general services from an affiliate, Corporate Services. These services are billed to IPL and WPL at cost based on expenses incurred by Corporate Services for the benefit of IPL and WPL, respectively. These costs consisted primarily of employee compensation and benefits, fees associated with various professional services, depreciation and amortization of property, plant and equipment, and a return on net assets. Corporate Services also acts as agent on behalf of IPL and WPL pursuant to the service agreements. As agent, Corporate Services enters into energy, capacity, ancillary services, and transmission sale and purchase transactions within MISO. Corporate Services assigns such sales and purchases among IPL and WPL based on statements received from MISO. The amounts billed for services provided, sales credited and purchases for the three and six months ended June 30 were as follows (in millions):

	IPL								WPL
	Three Months				Six Months				Three Months				Six Months
	2020		2019		2020		2019		2020		2019		2020		2019
Corporate Services billings		$44		$47		$81		$90		$35		$35		$67		$68
Sales credited	10		12		25		27		2		3		4		4
Purchases billed	57		74		138		158		20		29		40		59

Net intercompany payables to Corporate Services were as follows (in millions):

	IPL		WPL
	June 30, 2020	December 31, 2019	June 30, 2020	December 31, 2019
Net payables to Corporate Services	$93	$112	$65	$85

ATC - Pursuant to various agreements, WPL receives a range of transmission services from ATC. WPL provides operation, maintenance, and construction services to ATC. WPL and ATC also bill each other for use of shared facilities owned by each party. The related amounts billed between the parties for the three and six months ended June 30 were as follows (in millions):

	Three Months				Six Months
	2020		2019		2020		2019
ATC billings to WPL		$25		$27		$53		$54
WPL billings to ATC	3		3		6		7

WPL owed ATC net amounts of $9 million as of June 30, 2020 and $9 million as of December 31, 2019. In the second quarter of 2020, WPL received $46 million from ATC related to construction deposits WPL previously provided ATC for transmission network upgrades for the West Riverside Energy Center, which is recorded in “Other” in AEC’s and WPL’s cash flows from investing activities.

IPL [Member]

Related Party Transactions [Line Items]

Related Parties

RELATED PARTIES

Service Agreements - Pursuant to service agreements, IPL and WPL receive various administrative and general services from an affiliate, Corporate Services. These services are billed to IPL and WPL at cost based on expenses incurred by Corporate Services for the benefit of IPL and WPL, respectively. These costs consisted primarily of employee compensation and benefits, fees associated with various professional services, depreciation and amortization of property, plant and equipment, and a return on net assets. Corporate Services also acts as agent on behalf of IPL and WPL pursuant to the service agreements. As agent, Corporate Services enters into energy, capacity, ancillary services, and transmission sale and purchase transactions within MISO. Corporate Services assigns such sales and purchases among IPL and WPL based on statements received from MISO. The amounts billed for services provided, sales credited and purchases for the three and six months ended June 30 were as follows (in millions):

	IPL								WPL
	Three Months				Six Months				Three Months				Six Months
	2020		2019		2020		2019		2020		2019		2020		2019
Corporate Services billings		$44		$47		$81		$90		$35		$35		$67		$68
Sales credited	10		12		25		27		2		3		4		4
Purchases billed	57		74		138		158		20		29		40		59

Net intercompany payables to Corporate Services were as follows (in millions):

	IPL		WPL
	June 30, 2020	December 31, 2019	June 30, 2020	December 31, 2019
Net payables to Corporate Services	$93	$112	$65	$85

WPL [Member]

Related Party Transactions [Line Items]

Related Parties

RELATED PARTIES

Service Agreements - Pursuant to service agreements, IPL and WPL receive various administrative and general services from an affiliate, Corporate Services. These services are billed to IPL and WPL at cost based on expenses incurred by Corporate Services for the benefit of IPL and WPL, respectively. These costs consisted primarily of employee compensation and benefits, fees associated with various professional services, depreciation and amortization of property, plant and equipment, and a return on net assets. Corporate Services also acts as agent on behalf of IPL and WPL pursuant to the service agreements. As agent, Corporate Services enters into energy, capacity, ancillary services, and transmission sale and purchase transactions within MISO. Corporate Services assigns such sales and purchases among IPL and WPL based on statements received from MISO. The amounts billed for services provided, sales credited and purchases for the three and six months ended June 30 were as follows (in millions):

	IPL								WPL
	Three Months				Six Months				Three Months				Six Months
	2020		2019		2020		2019		2020		2019		2020		2019
Corporate Services billings		$44		$47		$81		$90		$35		$35		$67		$68
Sales credited	10		12		25		27		2		3		4		4
Purchases billed	57		74		138		158		20		29		40		59

Net intercompany payables to Corporate Services were as follows (in millions):

	IPL		WPL
	June 30, 2020	December 31, 2019	June 30, 2020	December 31, 2019
Net payables to Corporate Services	$93	$112	$65	$85

ATC - Pursuant to various agreements, WPL receives a range of transmission services from ATC. WPL provides operation, maintenance, and construction services to ATC. WPL and ATC also bill each other for use of shared facilities owned by each party. The related amounts billed between the parties for the three and six months ended June 30 were as follows (in millions):

	Three Months				Six Months
	2020		2019		2020		2019
ATC billings to WPL		$25		$27		$53		$54
WPL billings to ATC	3		3		6		7

WPL owed ATC net amounts of $9 million as of June 30, 2020 and $9 million as of December 31, 2019. In the second quarter of 2020, WPL received $46 million from ATC related to construction deposits WPL previously provided ATC for transmission network upgrades for the West Riverside Energy Center, which is recorded in “Other” in AEC’s and WPL’s cash flows from investing activities.

XML

Summary Of Significant Accounting Policies (Policy)

6 Months Ended

Jun. 30, 2020

General, Basis of Accounting

The interim unaudited Financial Statements included herein have been prepared pursuant to the rules and regulations of the Securities and Exchange Commission. Accordingly, certain information and note disclosures normally included in financial statements prepared in accordance with GAAP have been condensed or omitted, although management believes that the disclosures are adequate to make the information presented not misleading. These Financial Statements should be read in conjunction with the financial statements and the notes thereto included in the latest combined Annual Report on Form 10-K.

In the opinion of management, all adjustments, which unless otherwise noted are normal and recurring in nature, necessary for a fair presentation of the results of operations, financial position and cash flows have been made. Results for the six months ended June 30, 2020 are not necessarily indicative of results that may be expected for the year ending December 31, 2020.

General, COVID-19

In March 2020, COVID-19 was declared a global pandemic, which has resulted in widespread travel restrictions and closures of commercial spaces and industrial facilities in Alliant Energy’s service territories. For the three and six months ended June 30, 2020, Alliant Energy, IPL and WPL considered the impact of COVID-19 on their overall business operations, financial condition, results of operations and cash flows, along with assumptions and estimates used. While the total expected impact of COVID-19 on future sales is currently unknown, Alliant Energy, IPL and WPL have experienced higher electric residential sales and lower electric commercial and industrial sales since the outset of the pandemic. The degree to which the COVID-19 pandemic may impact Alliant Energy, IPL and WPL in the future is currently unknown and will depend on future developments of the pandemic as well as possible additional actions by government and regulatory authorities.

General, Use of Estimates

A change in management’s estimates or assumptions could have a material impact on financial condition and results of operations during the period in which such change occurred.

General, Reclassification

Certain prior period amounts in the Financial Statements and Notes have been reclassified to conform to the current period presentation for comparative purposes.

Cash and Cash Equivalents

At June 30, 2020, Alliant Energy’s and IPL’s cash and cash equivalents included $198.3 million and $198.3 million of money market fund investments, with weighted average interest rates of 0.1% and 0.1%, respectively.

Current Expected Credit Losses Estimates

Current expected credit losses are estimated for trade and other receivables and credit exposures on guarantees of the performance by third parties. The current expected credit losses for short-term trade receivables are based on estimates of losses resulting from the inability of customers to make required payments. The methodology used to estimate losses is based on historical write-offs, regional economic conditions, significant events that could impact collectability, such as impacts related to COVID-19 and related regulatory actions, and forecasted changes to the accounts receivable aging portfolio and write-offs. The current expected credit losses related to guarantees of the performance by third parties are estimated using both quantitative and qualitative information, which utilizes potential outcomes in a range of possible estimated amounts.

New Accounting Standards

Credit Losses - In June 2016, the Financial Accounting Standards Board issued an accounting standard requiring use of a current expected credit loss model rather than an incurred loss method, which is intended to result in more timely recognition of credit losses on trade receivables, certain other assets and off-balance sheet credit exposures. Alliant Energy, IPL and WPL adopted this standard on January 1, 2020 using a modified retrospective method of adoption, which required cumulative effect adjustments to retained earnings on January 1, 2020. IPL and WPL did not record a cumulative effect adjustment to retained earnings and Alliant Energy recorded a pre-tax $12 million (after-tax $8.7 million) cumulative effect adjustment to decrease retained earnings related to Alliant Energy’s guarantees in the partnership obligations of an affiliate of Whiting Petroleum (refer to Note 13(c) for further discussion). This adjustment is included in “Adoption of new accounting standard” in Alliant Energy’s summary of changes in shareowners’ equity in Note 5 for the six months ended June 30, 2020.

IPL [Member]

General, Basis of Accounting

The interim unaudited Financial Statements included herein have been prepared pursuant to the rules and regulations of the Securities and Exchange Commission. Accordingly, certain information and note disclosures normally included in financial statements prepared in accordance with GAAP have been condensed or omitted, although management believes that the disclosures are adequate to make the information presented not misleading. These Financial Statements should be read in conjunction with the financial statements and the notes thereto included in the latest combined Annual Report on Form 10-K.

In the opinion of management, all adjustments, which unless otherwise noted are normal and recurring in nature, necessary for a fair presentation of the results of operations, financial position and cash flows have been made. Results for the six months ended June 30, 2020 are not necessarily indicative of results that may be expected for the year ending December 31, 2020.

General, COVID-19

In March 2020, COVID-19 was declared a global pandemic, which has resulted in widespread travel restrictions and closures of commercial spaces and industrial facilities in Alliant Energy’s service territories. For the three and six months ended June 30, 2020, Alliant Energy, IPL and WPL considered the impact of COVID-19 on their overall business operations, financial condition, results of operations and cash flows, along with assumptions and estimates used. While the total expected impact of COVID-19 on future sales is currently unknown, Alliant Energy, IPL and WPL have experienced higher electric residential sales and lower electric commercial and industrial sales since the outset of the pandemic. The degree to which the COVID-19 pandemic may impact Alliant Energy, IPL and WPL in the future is currently unknown and will depend on future developments of the pandemic as well as possible additional actions by government and regulatory authorities.

General, Use of Estimates

A change in management’s estimates or assumptions could have a material impact on financial condition and results of operations during the period in which such change occurred.

General, Reclassification

Certain prior period amounts in the Financial Statements and Notes have been reclassified to conform to the current period presentation for comparative purposes.

Cash and Cash Equivalents

At June 30, 2020, Alliant Energy’s and IPL’s cash and cash equivalents included $198.3 million and $198.3 million of money market fund investments, with weighted average interest rates of 0.1% and 0.1%, respectively.

Current Expected Credit Losses Estimates

Current expected credit losses are estimated for trade and other receivables and credit exposures on guarantees of the performance by third parties. The current expected credit losses for short-term trade receivables are based on estimates of losses resulting from the inability of customers to make required payments. The methodology used to estimate losses is based on historical write-offs, regional economic conditions, significant events that could impact collectability, such as impacts related to COVID-19 and related regulatory actions, and forecasted changes to the accounts receivable aging portfolio and write-offs. The current expected credit losses related to guarantees of the performance by third parties are estimated using both quantitative and qualitative information, which utilizes potential outcomes in a range of possible estimated amounts.

New Accounting Standards

Credit Losses - In June 2016, the Financial Accounting Standards Board issued an accounting standard requiring use of a current expected credit loss model rather than an incurred loss method, which is intended to result in more timely recognition of credit losses on trade receivables, certain other assets and off-balance sheet credit exposures. Alliant Energy, IPL and WPL adopted this standard on January 1, 2020 using a modified retrospective method of adoption, which required cumulative effect adjustments to retained earnings on January 1, 2020. IPL and WPL did not record a cumulative effect adjustment to retained earnings and Alliant Energy recorded a pre-tax $12 million (after-tax $8.7 million) cumulative effect adjustment to decrease retained earnings related to Alliant Energy’s guarantees in the partnership obligations of an affiliate of Whiting Petroleum (refer to Note 13(c) for further discussion). This adjustment is included in “Adoption of new accounting standard” in Alliant Energy’s summary of changes in shareowners’ equity in Note 5 for the six months ended June 30, 2020.

WPL [Member]

General, Basis of Accounting

The interim unaudited Financial Statements included herein have been prepared pursuant to the rules and regulations of the Securities and Exchange Commission. Accordingly, certain information and note disclosures normally included in financial statements prepared in accordance with GAAP have been condensed or omitted, although management believes that the disclosures are adequate to make the information presented not misleading. These Financial Statements should be read in conjunction with the financial statements and the notes thereto included in the latest combined Annual Report on Form 10-K.

In the opinion of management, all adjustments, which unless otherwise noted are normal and recurring in nature, necessary for a fair presentation of the results of operations, financial position and cash flows have been made. Results for the six months ended June 30, 2020 are not necessarily indicative of results that may be expected for the year ending December 31, 2020.

General, COVID-19

In March 2020, COVID-19 was declared a global pandemic, which has resulted in widespread travel restrictions and closures of commercial spaces and industrial facilities in Alliant Energy’s service territories. For the three and six months ended June 30, 2020, Alliant Energy, IPL and WPL considered the impact of COVID-19 on their overall business operations, financial condition, results of operations and cash flows, along with assumptions and estimates used. While the total expected impact of COVID-19 on future sales is currently unknown, Alliant Energy, IPL and WPL have experienced higher electric residential sales and lower electric commercial and industrial sales since the outset of the pandemic. The degree to which the COVID-19 pandemic may impact Alliant Energy, IPL and WPL in the future is currently unknown and will depend on future developments of the pandemic as well as possible additional actions by government and regulatory authorities.

General, Use of Estimates

A change in management’s estimates or assumptions could have a material impact on financial condition and results of operations during the period in which such change occurred.

General, Reclassification

Certain prior period amounts in the Financial Statements and Notes have been reclassified to conform to the current period presentation for comparative purposes.

Current Expected Credit Losses Estimates

Current expected credit losses are estimated for trade and other receivables and credit exposures on guarantees of the performance by third parties. The current expected credit losses for short-term trade receivables are based on estimates of losses resulting from the inability of customers to make required payments. The methodology used to estimate losses is based on historical write-offs, regional economic conditions, significant events that could impact collectability, such as impacts related to COVID-19 and related regulatory actions, and forecasted changes to the accounts receivable aging portfolio and write-offs. The current expected credit losses related to guarantees of the performance by third parties are estimated using both quantitative and qualitative information, which utilizes potential outcomes in a range of possible estimated amounts.

New Accounting Standards

Credit Losses - In June 2016, the Financial Accounting Standards Board issued an accounting standard requiring use of a current expected credit loss model rather than an incurred loss method, which is intended to result in more timely recognition of credit losses on trade receivables, certain other assets and off-balance sheet credit exposures. Alliant Energy, IPL and WPL adopted this standard on January 1, 2020 using a modified retrospective method of adoption, which required cumulative effect adjustments to retained earnings on January 1, 2020. IPL and WPL did not record a cumulative effect adjustment to retained earnings and Alliant Energy recorded a pre-tax $12 million (after-tax $8.7 million) cumulative effect adjustment to decrease retained earnings related to Alliant Energy’s guarantees in the partnership obligations of an affiliate of Whiting Petroleum (refer to Note 13(c) for further discussion). This adjustment is included in “Adoption of new accounting standard” in Alliant Energy’s summary of changes in shareowners’ equity in Note 5 for the six months ended June 30, 2020.

XML

Regulatory Matters (Tables)

6 Months Ended

Jun. 30, 2020

Regulatory Assets [Line Items]

Regulatory Assets

Regulatory assets were comprised of the following items (in millions):

	Alliant Energy				IPL				WPL
	June 30, 2020		December 31, 2019		June 30, 2020		December 31, 2019		June 30, 2020		December 31, 2019
Tax-related		$842.5		$817.6		$797.4		$776.8		$45.1		$40.8
Pension and OPEB costs	501.2		524.0		251.3		262.5		249.9		261.5
Assets retired early	122.9		134.0		81.8		87.9		41.1		46.1
Asset retirement obligations	114.0		111.8		78.2		76.2		35.8		35.6
IPL’s DAEC PPA amendment	109.4		108.2		109.4		108.2		—		—
Derivatives	47.0		39.5		20.5		18.3		26.5		21.2
Emission allowances	19.8		21.1		19.8		21.1		—		—
Other	86.2		88.5		46.5		48.3		39.7		40.2
		$1,843.0		$1,844.7		$1,404.9		$1,399.3		$438.1		$445.4

Regulatory Liabilities

Regulatory liabilities were comprised of the following items (in millions):

	Alliant Energy				IPL				WPL
	June 30, 2020		December 31, 2019		June 30, 2020		December 31, 2019		June 30, 2020		December 31, 2019
Tax-related		$779.0		$835.6		$343.6		$350.9		$435.4		$484.7
Cost of removal obligations	385.8		387.7		256.4		257.0		129.4		130.7
Electric transmission cost recovery	66.3		88.6		30.7		51.3		35.6		37.3
Commodity cost recovery	30.1		24.2		14.0		8.8		16.1		15.4
Derivatives	28.8		19.9		26.3		17.4		2.5		2.5
WPL’s earnings sharing mechanism	20.4		21.9		—		—		20.4		21.9
Other	60.6		45.7		46.9		29.3		13.7		16.4
		$1,371.0		$1,423.6		$717.9		$714.7		$653.1		$708.9

IPL [Member]

Regulatory Assets [Line Items]

Regulatory Assets

Regulatory assets were comprised of the following items (in millions):

	Alliant Energy				IPL				WPL
	June 30, 2020		December 31, 2019		June 30, 2020		December 31, 2019		June 30, 2020		December 31, 2019
Tax-related		$842.5		$817.6		$797.4		$776.8		$45.1		$40.8
Pension and OPEB costs	501.2		524.0		251.3		262.5		249.9		261.5
Assets retired early	122.9		134.0		81.8		87.9		41.1		46.1
Asset retirement obligations	114.0		111.8		78.2		76.2		35.8		35.6
IPL’s DAEC PPA amendment	109.4		108.2		109.4		108.2		—		—
Derivatives	47.0		39.5		20.5		18.3		26.5		21.2
Emission allowances	19.8		21.1		19.8		21.1		—		—
Other	86.2		88.5		46.5		48.3		39.7		40.2
		$1,843.0		$1,844.7		$1,404.9		$1,399.3		$438.1		$445.4

Regulatory Liabilities

Regulatory liabilities were comprised of the following items (in millions):

	Alliant Energy				IPL				WPL
	June 30, 2020		December 31, 2019		June 30, 2020		December 31, 2019		June 30, 2020		December 31, 2019
Tax-related		$779.0		$835.6		$343.6		$350.9		$435.4		$484.7
Cost of removal obligations	385.8		387.7		256.4		257.0		129.4		130.7
Electric transmission cost recovery	66.3		88.6		30.7		51.3		35.6		37.3
Commodity cost recovery	30.1		24.2		14.0		8.8		16.1		15.4
Derivatives	28.8		19.9		26.3		17.4		2.5		2.5
WPL’s earnings sharing mechanism	20.4		21.9		—		—		20.4		21.9
Other	60.6		45.7		46.9		29.3		13.7		16.4
		$1,371.0		$1,423.6		$717.9		$714.7		$653.1		$708.9

WPL [Member]

Regulatory Assets [Line Items]

Regulatory Assets

Regulatory assets were comprised of the following items (in millions):

	Alliant Energy				IPL				WPL
	June 30, 2020		December 31, 2019		June 30, 2020		December 31, 2019		June 30, 2020		December 31, 2019
Tax-related		$842.5		$817.6		$797.4		$776.8		$45.1		$40.8
Pension and OPEB costs	501.2		524.0		251.3		262.5		249.9		261.5
Assets retired early	122.9		134.0		81.8		87.9		41.1		46.1
Asset retirement obligations	114.0		111.8		78.2		76.2		35.8		35.6
IPL’s DAEC PPA amendment	109.4		108.2		109.4		108.2		—		—
Derivatives	47.0		39.5		20.5		18.3		26.5		21.2
Emission allowances	19.8		21.1		19.8		21.1		—		—
Other	86.2		88.5		46.5		48.3		39.7		40.2
		$1,843.0		$1,844.7		$1,404.9		$1,399.3		$438.1		$445.4

Regulatory Liabilities

Regulatory liabilities were comprised of the following items (in millions):

	Alliant Energy				IPL				WPL
	June 30, 2020		December 31, 2019		June 30, 2020		December 31, 2019		June 30, 2020		December 31, 2019
Tax-related		$779.0		$835.6		$343.6		$350.9		$435.4		$484.7
Cost of removal obligations	385.8		387.7		256.4		257.0		129.4		130.7
Electric transmission cost recovery	66.3		88.6		30.7		51.3		35.6		37.3
Commodity cost recovery	30.1		24.2		14.0		8.8		16.1		15.4
Derivatives	28.8		19.9		26.3		17.4		2.5		2.5
WPL’s earnings sharing mechanism	20.4		21.9		—		—		20.4		21.9
Other	60.6		45.7		46.9		29.3		13.7		16.4
		$1,371.0		$1,423.6		$717.9		$714.7		$653.1		$708.9

XML

Receivables (Tables)

6 Months Ended

Jun. 30, 2020

Receivables [Line Items]

Accounts Receivable Details

Details for accounts receivable included on the balance sheets were as follows (in millions):

	Alliant Energy						IPL						WPL
	June 30, 2020			December 31, 2019			June 30, 2020			December 31, 2019			June 30, 2020			December 31, 2019
Customer		$92.7			$91.6			$—			$—			$82.4			$83.5
Unbilled utility revenues	68.2			82.1			—			—			68.2			82.1
Deferred proceeds	194.1			187.7			194.1			187.7			—			—
Other	41.5			48.0			16.5			16.3			24.5			31.4
Allowance for expected credit losses	(10.0		)	(7.3		)	(1.7		)	(1.2		)	(8.2		)	(6.1		)
		$386.5			$402.1			$208.9			$202.8			$166.9			$190.9

Maximum And Average Outstanding Cash Proceeds

IPL’s maximum and average outstanding cash proceeds (based on daily outstanding balances) related to the sales of accounts receivable program for the three and six months ended June 30 were as follows (in millions):

	Three Months				Six Months
	2020		2019		2020		2019
Maximum outstanding aggregate cash proceeds		$65.0		$25.0		$96.0		$108.0
Average outstanding aggregate cash proceeds	11.1		2.6		17.3		41.6

Schedule of Sales Of Accounts Receivable Sold Under Agreement Table Text Block

The attributes of IPL’s receivables sold under the Receivables Agreement were as follows (in millions):

	June 30, 2020		December 31, 2019
Customer accounts receivable		$113.5		$124.7
Unbilled utility revenues	92.3		95.5
Other receivables	0.4		0.9
Receivables sold to third party	206.2		221.1
Less: cash proceeds	1.0		27.0
Deferred proceeds	205.2		194.1
Less: allowance for expected credit losses	11.1		6.4
Fair value of deferred proceeds		$194.1		$187.7

Additional Attributes Of Receivables Sold Under The Receivables Agreement

Additional attributes of IPL’s receivables sold under the Receivables Agreement for the three and six months ended June 30 were as follows (in millions):

	Three Months				Six Months
	2020		2019		2020		2019
Collections		$453.0		$487.7		$994.4		$1,043.5
Write-offs, net of recoveries	1.2		2.6		3.3		8.1

IPL [Member]

Receivables [Line Items]

Accounts Receivable Details

Details for accounts receivable included on the balance sheets were as follows (in millions):

	Alliant Energy						IPL						WPL
	June 30, 2020			December 31, 2019			June 30, 2020			December 31, 2019			June 30, 2020			December 31, 2019
Customer		$92.7			$91.6			$—			$—			$82.4			$83.5
Unbilled utility revenues	68.2			82.1			—			—			68.2			82.1
Deferred proceeds	194.1			187.7			194.1			187.7			—			—
Other	41.5			48.0			16.5			16.3			24.5			31.4
Allowance for expected credit losses	(10.0		)	(7.3		)	(1.7		)	(1.2		)	(8.2		)	(6.1		)
		$386.5			$402.1			$208.9			$202.8			$166.9			$190.9

Maximum And Average Outstanding Cash Proceeds

IPL’s maximum and average outstanding cash proceeds (based on daily outstanding balances) related to the sales of accounts receivable program for the three and six months ended June 30 were as follows (in millions):

	Three Months				Six Months
	2020		2019		2020		2019
Maximum outstanding aggregate cash proceeds		$65.0		$25.0		$96.0		$108.0
Average outstanding aggregate cash proceeds	11.1		2.6		17.3		41.6

Schedule of Sales Of Accounts Receivable Sold Under Agreement Table Text Block

The attributes of IPL’s receivables sold under the Receivables Agreement were as follows (in millions):

	June 30, 2020		December 31, 2019
Customer accounts receivable		$113.5		$124.7
Unbilled utility revenues	92.3		95.5
Other receivables	0.4		0.9
Receivables sold to third party	206.2		221.1
Less: cash proceeds	1.0		27.0
Deferred proceeds	205.2		194.1
Less: allowance for expected credit losses	11.1		6.4
Fair value of deferred proceeds		$194.1		$187.7

Additional Attributes Of Receivables Sold Under The Receivables Agreement

Additional attributes of IPL’s receivables sold under the Receivables Agreement for the three and six months ended June 30 were as follows (in millions):

	Three Months				Six Months
	2020		2019		2020		2019
Collections		$453.0		$487.7		$994.4		$1,043.5
Write-offs, net of recoveries	1.2		2.6		3.3		8.1

WPL [Member]

Receivables [Line Items]

Accounts Receivable Details

Details for accounts receivable included on the balance sheets were as follows (in millions):

	Alliant Energy						IPL						WPL
	June 30, 2020			December 31, 2019			June 30, 2020			December 31, 2019			June 30, 2020			December 31, 2019
Customer		$92.7			$91.6			$—			$—			$82.4			$83.5
Unbilled utility revenues	68.2			82.1			—			—			68.2			82.1
Deferred proceeds	194.1			187.7			194.1			187.7			—			—
Other	41.5			48.0			16.5			16.3			24.5			31.4
Allowance for expected credit losses	(10.0		)	(7.3		)	(1.7		)	(1.2		)	(8.2		)	(6.1		)
		$386.5			$402.1			$208.9			$202.8			$166.9			$190.9

XML

Investments (Tables)

6 Months Ended

Jun. 30, 2020

Schedule of Equity Method Investments [Line Items]

Unconsolidated Equity Investments

Alliant Energy’s equity (income) loss from unconsolidated investments accounted for under the equity method of accounting for the three and six months ended June 30 was as follows (in millions):

	Three Months						Six Months
	2020			2019			2020			2019
ATC Holdings		($13.5	)		($10.0	)		($24.5	)		($19.5	)
Non-utility wind farm in Oklahoma	(1.9		)	(1.3		)	(4.1		)	(2.4		)
Other	(2.0		)	(1.4		)	(2.2		)	(1.7		)
		($17.4	)		($12.7	)		($30.8	)		($23.6	)

XML

Common Equity (Tables)

6 Months Ended

Jun. 30, 2020

Schedule of Capitalization, Equity [Line Items]

Common Share Activity

A summary of Alliant Energy’s common stock activity was as follows:

Shares outstanding, January 1, 2020	245,022,800
Equity forward agreements	4,275,127
Shareowner Direct Plan	248,220
Equity-based compensation plans	98,205
Shares outstanding, June 30, 2020	249,644,352

Changes in Shareowners' Equity

A summary of changes in shareowners’ equity was as follows (in millions):

Alliant Energy	Total Alliant Energy Common Equity
								Accumulated			Shares in			Cumulative
			Additional					Other			Deferred			Preferred
	Common		Paid-In		Retained			Comprehensive			Compensation			Stock		Total
	Stock		Capital		Earnings			Income (Loss)			Trust			of IPL		Equity
Three Months Ended June 30, 2020
Beginning balance, March 31, 2020		$2.5		$2,674.1		$2,833.7			$2.0			($9.9	)		$200.0		$5,702.4
Net income attributable to Alliant Energy common shareowners					134.4											134.4
Common stock dividends ($0.38 per share)					(94.6		)									(94.6		)
Shareowner Direct Plan issuances			6.4													6.4
Equity-based compensation plans and other			2.6								(0.3		)			2.3
Other comprehensive loss, net of tax								(2.6		)						(2.6		)
Ending balance, June 30, 2020		$2.5		$2,683.1		$2,873.5			($0.6	)		($10.2	)		$200.0		$5,748.3
Three Months Ended June 30, 2019
Beginning balance, March 31, 2019		$2.4		$2,100.0		$2,587.3			$2.4			($9.7	)		$200.0		$4,882.4
Net income attributable to Alliant Energy common shareowners					94.6											94.6
Common stock dividends ($0.355 per share)					(84.1		)									(84.1		)
Shareowner Direct Plan issuances			6.0													6.0
Equity-based compensation plans and other			2.4								(0.3		)			2.1
Other comprehensive loss, net of tax								(1.4		)						(1.4		)
Ending balance, June 30, 2019		$2.4		$2,108.4		$2,597.8			$1.0			($10.0	)		$200.0		$4,899.6

Alliant Energy	Total Alliant Energy Common Equity
								Accumulated			Shares in			Cumulative
			Additional					Other			Deferred			Preferred
	Common		Paid-In		Retained			Comprehensive			Compensation			Stock		Total
	Stock		Capital		Earnings			Income (Loss)			Trust			of IPL		Equity
Six Months Ended June 30, 2020
Beginning balance, December 31, 2019		$2.5		$2,445.9		$2,765.4			$1.3			($10.0	)		$200.0		$5,405.1
Net income attributable to Alliant Energy common shareowners					304.4											304.4
Common stock dividends ($0.76 per share)					(187.6		)									(187.6		)
Equity forward settlements and Shareowner Direct Plan issuances			234.8													234.8
Equity-based compensation plans and other			2.4								(0.2		)			2.2
Adoption of new accounting standard, net of tax (refer to Note 1(d))					(8.7		)									(8.7		)
Other comprehensive loss, net of tax								(1.9		)						(1.9		)
Ending balance, June 30, 2020		$2.5		$2,683.1		$2,873.5			($0.6	)		($10.2	)		$200.0		$5,748.3
Six Months Ended June 30, 2019
Beginning balance, December 31, 2018		$2.4		$2,045.5		$2,545.9			$1.7			($9.8	)		$200.0		$4,785.7
Net income attributable to Alliant Energy common shareowners					219.7											219.7
Common stock dividends ($0.71 per share)					(167.8		)									(167.8		)
Equity forward settlements and Shareowner Direct Plan issuances			60.6													60.6
Equity-based compensation plans and other			2.3								(0.2		)			2.1
Other comprehensive loss, net of tax								(0.7		)						(0.7		)
Ending balance, June 30, 2019		$2.4		$2,108.4		$2,597.8			$1.0			($10.0	)		$200.0		$4,899.6

IPL	Total IPL Common Equity
			Additional					Cumulative
	Common		Paid-In		Retained			Preferred		Total
	Stock		Capital		Earnings			Stock		Equity
Three Months Ended June 30, 2020
Beginning balance, March 31, 2020		$33.4		$2,447.8		$914.2			$200.0		$3,595.4
Net income available for common stock					59.8					59.8
Common stock dividends					(59.1		)			(59.1		)
Capital contributions from parent			75.0							75.0
Ending balance, June 30, 2020		$33.4		$2,522.8		$914.9			$200.0		$3,671.1
Three Months Ended June 30, 2019
Beginning balance, March 31, 2019		$33.4		$2,322.8		$785.8			$200.0		$3,342.0
Net income available for common stock					45.0					45.0
Common stock dividends					(41.9		)			(41.9		)
Ending balance, June 30, 2019		$33.4		$2,322.8		$788.9			$200.0		$3,345.1

IPL	Total IPL Common Equity
			Additional					Cumulative
	Common		Paid-In		Retained			Preferred		Total
	Stock		Capital		Earnings			Stock		Equity
Six Months Ended June 30, 2020
Beginning balance, December 31, 2019		$33.4		$2,347.8		$890.6			$200.0		$3,471.8
Net income available for common stock					142.4					142.4
Common stock dividends					(118.1		)			(118.1		)
Capital contributions from parent			175.0							175.0
Ending balance, June 30, 2020		$33.4		$2,522.8		$914.9			$200.0		$3,671.1
Six Months Ended June 30, 2019
Beginning balance, December 31, 2018		$33.4		$2,222.8		$774.5			$200.0		$3,230.7
Net income available for common stock					98.3					98.3
Common stock dividends					(83.9		)			(83.9		)
Capital contributions from parent			100.0							100.0
Ending balance, June 30, 2019		$33.4		$2,322.8		$788.9			$200.0		$3,345.1

WPL			Additional					Total
	Common		Paid-In		Retained			Common
	Stock		Capital		Earnings			Equity
Three Months Ended June 30, 2020
Beginning balance, March 31, 2020		$66.2		$1,459.0		$910.9			$2,436.1
Net income					57.6			57.6
Common stock dividends					(41.9		)	(41.9		)
Ending balance, June 30, 2020		$66.2		$1,459.0		$926.6			$2,451.8
Three Months Ended June 30, 2019
Beginning balance, March 31, 2019		$66.2		$1,309.0		$804.0			$2,179.2
Net income					42.0			42.0
Common stock dividends					(36.0		)	(36.0		)
Ending balance, June 30, 2019		$66.2		$1,309.0		$810.0			$2,185.2

WPL			Additional					Total
	Common		Paid-In		Retained			Common
	Stock		Capital		Earnings			Equity
Six Months Ended June 30, 2020
Beginning balance, December 31, 2019		$66.2		$1,434.0		$863.4			$2,363.6
Net income					147.2			147.2
Common stock dividends					(84.0		)	(84.0		)
Capital contributions from parent			25.0					25.0
Ending balance, June 30, 2020		$66.2		$1,459.0		$926.6			$2,451.8
Six Months Ended June 30, 2019
Beginning balance, December 31, 2018		$66.2		$1,309.0		$774.3			$2,149.5
Net income					107.7			107.7
Common stock dividends					(72.0		)	(72.0		)
Ending balance, June 30, 2019		$66.2		$1,309.0		$810.0			$2,185.2

IPL [Member]

Schedule of Capitalization, Equity [Line Items]

Changes in Shareowners' Equity

A summary of changes in shareowners’ equity was as follows (in millions):

Alliant Energy	Total Alliant Energy Common Equity
								Accumulated			Shares in			Cumulative
			Additional					Other			Deferred			Preferred
	Common		Paid-In		Retained			Comprehensive			Compensation			Stock		Total
	Stock		Capital		Earnings			Income (Loss)			Trust			of IPL		Equity
Three Months Ended June 30, 2020
Beginning balance, March 31, 2020		$2.5		$2,674.1		$2,833.7			$2.0			($9.9	)		$200.0		$5,702.4
Net income attributable to Alliant Energy common shareowners					134.4											134.4
Common stock dividends ($0.38 per share)					(94.6		)									(94.6		)
Shareowner Direct Plan issuances			6.4													6.4
Equity-based compensation plans and other			2.6								(0.3		)			2.3
Other comprehensive loss, net of tax								(2.6		)						(2.6		)
Ending balance, June 30, 2020		$2.5		$2,683.1		$2,873.5			($0.6	)		($10.2	)		$200.0		$5,748.3
Three Months Ended June 30, 2019
Beginning balance, March 31, 2019		$2.4		$2,100.0		$2,587.3			$2.4			($9.7	)		$200.0		$4,882.4
Net income attributable to Alliant Energy common shareowners					94.6											94.6
Common stock dividends ($0.355 per share)					(84.1		)									(84.1		)
Shareowner Direct Plan issuances			6.0													6.0
Equity-based compensation plans and other			2.4								(0.3		)			2.1
Other comprehensive loss, net of tax								(1.4		)						(1.4		)
Ending balance, June 30, 2019		$2.4		$2,108.4		$2,597.8			$1.0			($10.0	)		$200.0		$4,899.6

Alliant Energy	Total Alliant Energy Common Equity
								Accumulated			Shares in			Cumulative
			Additional					Other			Deferred			Preferred
	Common		Paid-In		Retained			Comprehensive			Compensation			Stock		Total
	Stock		Capital		Earnings			Income (Loss)			Trust			of IPL		Equity
Six Months Ended June 30, 2020
Beginning balance, December 31, 2019		$2.5		$2,445.9		$2,765.4			$1.3			($10.0	)		$200.0		$5,405.1
Net income attributable to Alliant Energy common shareowners					304.4											304.4
Common stock dividends ($0.76 per share)					(187.6		)									(187.6		)
Equity forward settlements and Shareowner Direct Plan issuances			234.8													234.8
Equity-based compensation plans and other			2.4								(0.2		)			2.2
Adoption of new accounting standard, net of tax (refer to Note 1(d))					(8.7		)									(8.7		)
Other comprehensive loss, net of tax								(1.9		)						(1.9		)
Ending balance, June 30, 2020		$2.5		$2,683.1		$2,873.5			($0.6	)		($10.2	)		$200.0		$5,748.3
Six Months Ended June 30, 2019
Beginning balance, December 31, 2018		$2.4		$2,045.5		$2,545.9			$1.7			($9.8	)		$200.0		$4,785.7
Net income attributable to Alliant Energy common shareowners					219.7											219.7
Common stock dividends ($0.71 per share)					(167.8		)									(167.8		)
Equity forward settlements and Shareowner Direct Plan issuances			60.6													60.6
Equity-based compensation plans and other			2.3								(0.2		)			2.1
Other comprehensive loss, net of tax								(0.7		)						(0.7		)
Ending balance, June 30, 2019		$2.4		$2,108.4		$2,597.8			$1.0			($10.0	)		$200.0		$4,899.6

IPL	Total IPL Common Equity
			Additional					Cumulative
	Common		Paid-In		Retained			Preferred		Total
	Stock		Capital		Earnings			Stock		Equity
Three Months Ended June 30, 2020
Beginning balance, March 31, 2020		$33.4		$2,447.8		$914.2			$200.0		$3,595.4
Net income available for common stock					59.8					59.8
Common stock dividends					(59.1		)			(59.1		)
Capital contributions from parent			75.0							75.0
Ending balance, June 30, 2020		$33.4		$2,522.8		$914.9			$200.0		$3,671.1
Three Months Ended June 30, 2019
Beginning balance, March 31, 2019		$33.4		$2,322.8		$785.8			$200.0		$3,342.0
Net income available for common stock					45.0					45.0
Common stock dividends					(41.9		)			(41.9		)
Ending balance, June 30, 2019		$33.4		$2,322.8		$788.9			$200.0		$3,345.1

IPL	Total IPL Common Equity
			Additional					Cumulative
	Common		Paid-In		Retained			Preferred		Total
	Stock		Capital		Earnings			Stock		Equity
Six Months Ended June 30, 2020
Beginning balance, December 31, 2019		$33.4		$2,347.8		$890.6			$200.0		$3,471.8
Net income available for common stock					142.4					142.4
Common stock dividends					(118.1		)			(118.1		)
Capital contributions from parent			175.0							175.0
Ending balance, June 30, 2020		$33.4		$2,522.8		$914.9			$200.0		$3,671.1
Six Months Ended June 30, 2019
Beginning balance, December 31, 2018		$33.4		$2,222.8		$774.5			$200.0		$3,230.7
Net income available for common stock					98.3					98.3
Common stock dividends					(83.9		)			(83.9		)
Capital contributions from parent			100.0							100.0
Ending balance, June 30, 2019		$33.4		$2,322.8		$788.9			$200.0		$3,345.1

WPL			Additional					Total
	Common		Paid-In		Retained			Common
	Stock		Capital		Earnings			Equity
Three Months Ended June 30, 2020
Beginning balance, March 31, 2020		$66.2		$1,459.0		$910.9			$2,436.1
Net income					57.6			57.6
Common stock dividends					(41.9		)	(41.9		)
Ending balance, June 30, 2020		$66.2		$1,459.0		$926.6			$2,451.8
Three Months Ended June 30, 2019
Beginning balance, March 31, 2019		$66.2		$1,309.0		$804.0			$2,179.2
Net income					42.0			42.0
Common stock dividends					(36.0		)	(36.0		)
Ending balance, June 30, 2019		$66.2		$1,309.0		$810.0			$2,185.2

WPL			Additional					Total
	Common		Paid-In		Retained			Common
	Stock		Capital		Earnings			Equity
Six Months Ended June 30, 2020
Beginning balance, December 31, 2019		$66.2		$1,434.0		$863.4			$2,363.6
Net income					147.2			147.2
Common stock dividends					(84.0		)	(84.0		)
Capital contributions from parent			25.0					25.0
Ending balance, June 30, 2020		$66.2		$1,459.0		$926.6			$2,451.8
Six Months Ended June 30, 2019
Beginning balance, December 31, 2018		$66.2		$1,309.0		$774.3			$2,149.5
Net income					107.7			107.7
Common stock dividends					(72.0		)	(72.0		)
Ending balance, June 30, 2019		$66.2		$1,309.0		$810.0			$2,185.2

WPL [Member]

Schedule of Capitalization, Equity [Line Items]

Changes in Shareowners' Equity

A summary of changes in shareowners’ equity was as follows (in millions):

Alliant Energy	Total Alliant Energy Common Equity
								Accumulated			Shares in			Cumulative
			Additional					Other			Deferred			Preferred
	Common		Paid-In		Retained			Comprehensive			Compensation			Stock		Total
	Stock		Capital		Earnings			Income (Loss)			Trust			of IPL		Equity
Three Months Ended June 30, 2020
Beginning balance, March 31, 2020		$2.5		$2,674.1		$2,833.7			$2.0			($9.9	)		$200.0		$5,702.4
Net income attributable to Alliant Energy common shareowners					134.4											134.4
Common stock dividends ($0.38 per share)					(94.6		)									(94.6		)
Shareowner Direct Plan issuances			6.4													6.4
Equity-based compensation plans and other			2.6								(0.3		)			2.3
Other comprehensive loss, net of tax								(2.6		)						(2.6		)
Ending balance, June 30, 2020		$2.5		$2,683.1		$2,873.5			($0.6	)		($10.2	)		$200.0		$5,748.3
Three Months Ended June 30, 2019
Beginning balance, March 31, 2019		$2.4		$2,100.0		$2,587.3			$2.4			($9.7	)		$200.0		$4,882.4
Net income attributable to Alliant Energy common shareowners					94.6											94.6
Common stock dividends ($0.355 per share)					(84.1		)									(84.1		)
Shareowner Direct Plan issuances			6.0													6.0
Equity-based compensation plans and other			2.4								(0.3		)			2.1
Other comprehensive loss, net of tax								(1.4		)						(1.4		)
Ending balance, June 30, 2019		$2.4		$2,108.4		$2,597.8			$1.0			($10.0	)		$200.0		$4,899.6

Alliant Energy	Total Alliant Energy Common Equity
								Accumulated			Shares in			Cumulative
			Additional					Other			Deferred			Preferred
	Common		Paid-In		Retained			Comprehensive			Compensation			Stock		Total
	Stock		Capital		Earnings			Income (Loss)			Trust			of IPL		Equity
Six Months Ended June 30, 2020
Beginning balance, December 31, 2019		$2.5		$2,445.9		$2,765.4			$1.3			($10.0	)		$200.0		$5,405.1
Net income attributable to Alliant Energy common shareowners					304.4											304.4
Common stock dividends ($0.76 per share)					(187.6		)									(187.6		)
Equity forward settlements and Shareowner Direct Plan issuances			234.8													234.8
Equity-based compensation plans and other			2.4								(0.2		)			2.2
Adoption of new accounting standard, net of tax (refer to Note 1(d))					(8.7		)									(8.7		)
Other comprehensive loss, net of tax								(1.9		)						(1.9		)
Ending balance, June 30, 2020		$2.5		$2,683.1		$2,873.5			($0.6	)		($10.2	)		$200.0		$5,748.3
Six Months Ended June 30, 2019
Beginning balance, December 31, 2018		$2.4		$2,045.5		$2,545.9			$1.7			($9.8	)		$200.0		$4,785.7
Net income attributable to Alliant Energy common shareowners					219.7											219.7
Common stock dividends ($0.71 per share)					(167.8		)									(167.8		)
Equity forward settlements and Shareowner Direct Plan issuances			60.6													60.6
Equity-based compensation plans and other			2.3								(0.2		)			2.1
Other comprehensive loss, net of tax								(0.7		)						(0.7		)
Ending balance, June 30, 2019		$2.4		$2,108.4		$2,597.8			$1.0			($10.0	)		$200.0		$4,899.6

IPL	Total IPL Common Equity
			Additional					Cumulative
	Common		Paid-In		Retained			Preferred		Total
	Stock		Capital		Earnings			Stock		Equity
Three Months Ended June 30, 2020
Beginning balance, March 31, 2020		$33.4		$2,447.8		$914.2			$200.0		$3,595.4
Net income available for common stock					59.8					59.8
Common stock dividends					(59.1		)			(59.1		)
Capital contributions from parent			75.0							75.0
Ending balance, June 30, 2020		$33.4		$2,522.8		$914.9			$200.0		$3,671.1
Three Months Ended June 30, 2019
Beginning balance, March 31, 2019		$33.4		$2,322.8		$785.8			$200.0		$3,342.0
Net income available for common stock					45.0					45.0
Common stock dividends					(41.9		)			(41.9		)
Ending balance, June 30, 2019		$33.4		$2,322.8		$788.9			$200.0		$3,345.1

IPL	Total IPL Common Equity
			Additional					Cumulative
	Common		Paid-In		Retained			Preferred		Total
	Stock		Capital		Earnings			Stock		Equity
Six Months Ended June 30, 2020
Beginning balance, December 31, 2019		$33.4		$2,347.8		$890.6			$200.0		$3,471.8
Net income available for common stock					142.4					142.4
Common stock dividends					(118.1		)			(118.1		)
Capital contributions from parent			175.0							175.0
Ending balance, June 30, 2020		$33.4		$2,522.8		$914.9			$200.0		$3,671.1
Six Months Ended June 30, 2019
Beginning balance, December 31, 2018		$33.4		$2,222.8		$774.5			$200.0		$3,230.7
Net income available for common stock					98.3					98.3
Common stock dividends					(83.9		)			(83.9		)
Capital contributions from parent			100.0							100.0
Ending balance, June 30, 2019		$33.4		$2,322.8		$788.9			$200.0		$3,345.1

WPL			Additional					Total
	Common		Paid-In		Retained			Common
	Stock		Capital		Earnings			Equity
Three Months Ended June 30, 2020
Beginning balance, March 31, 2020		$66.2		$1,459.0		$910.9			$2,436.1
Net income					57.6			57.6
Common stock dividends					(41.9		)	(41.9		)
Ending balance, June 30, 2020		$66.2		$1,459.0		$926.6			$2,451.8
Three Months Ended June 30, 2019
Beginning balance, March 31, 2019		$66.2		$1,309.0		$804.0			$2,179.2
Net income					42.0			42.0
Common stock dividends					(36.0		)	(36.0		)
Ending balance, June 30, 2019		$66.2		$1,309.0		$810.0			$2,185.2

WPL			Additional					Total
	Common		Paid-In		Retained			Common
	Stock		Capital		Earnings			Equity
Six Months Ended June 30, 2020
Beginning balance, December 31, 2019		$66.2		$1,434.0		$863.4			$2,363.6
Net income					147.2			147.2
Common stock dividends					(84.0		)	(84.0		)
Capital contributions from parent			25.0					25.0
Ending balance, June 30, 2020		$66.2		$1,459.0		$926.6			$2,451.8
Six Months Ended June 30, 2019
Beginning balance, December 31, 2018		$66.2		$1,309.0		$774.3			$2,149.5
Net income					107.7			107.7
Common stock dividends					(72.0		)	(72.0		)
Ending balance, June 30, 2019		$66.2		$1,309.0		$810.0			$2,185.2

XML

Debt (Tables)

6 Months Ended

Jun. 30, 2020

Short-term Debt [Line Items]

Other Short-Term Borrowings

Information regarding Alliant Energy’s, IPL’s and WPL’s commercial paper, and Alliant Energy’s and WPL’s borrowings under the single credit facility, which currently expires in August 2023, classified as short-term debt was as follows (dollars in millions):

June 30, 2020	Alliant Energy	IPL	WPL
Amount outstanding	$185.4	$—	$37.9
Weighted average interest rates	0.3%	N/A	0.2%
Available credit facility capacity	$814.6	$250.0	$262.1

	Alliant Energy		IPL		WPL
Three Months Ended June 30	2020	2019	2020	2019	2020	2019
Maximum amount outstanding (based on daily outstanding balances)	$270.5	$590.2	$8.4	$—	$182.0	$193.3
Average amount outstanding (based on daily outstanding balances)	$121.2	$531.7	$0.4	$—	$8.7	$141.6
Weighted average interest rates	0.5%	2.7%	0.5%	N/A	0.5%	2.5%
Six Months Ended June 30
Maximum amount outstanding (based on daily outstanding balances)	$462.5	$600.6	$8.4	$50.4	$212.0	$195.1
Average amount outstanding (based on daily outstanding balances)	$251.8	$515.4	$0.2	$0.3	$87.9	$139.8
Weighted average interest rates	1.5%	2.7%	0.5%	2.8%	1.7%	2.5%

IPL [Member]

Short-term Debt [Line Items]

Other Short-Term Borrowings

Information regarding Alliant Energy’s, IPL’s and WPL’s commercial paper, and Alliant Energy’s and WPL’s borrowings under the single credit facility, which currently expires in August 2023, classified as short-term debt was as follows (dollars in millions):

June 30, 2020	Alliant Energy	IPL	WPL
Amount outstanding	$185.4	$—	$37.9
Weighted average interest rates	0.3%	N/A	0.2%
Available credit facility capacity	$814.6	$250.0	$262.1

	Alliant Energy		IPL		WPL
Three Months Ended June 30	2020	2019	2020	2019	2020	2019
Maximum amount outstanding (based on daily outstanding balances)	$270.5	$590.2	$8.4	$—	$182.0	$193.3
Average amount outstanding (based on daily outstanding balances)	$121.2	$531.7	$0.4	$—	$8.7	$141.6
Weighted average interest rates	0.5%	2.7%	0.5%	N/A	0.5%	2.5%
Six Months Ended June 30
Maximum amount outstanding (based on daily outstanding balances)	$462.5	$600.6	$8.4	$50.4	$212.0	$195.1
Average amount outstanding (based on daily outstanding balances)	$251.8	$515.4	$0.2	$0.3	$87.9	$139.8
Weighted average interest rates	1.5%	2.7%	0.5%	2.8%	1.7%	2.5%

WPL [Member]

Short-term Debt [Line Items]

Other Short-Term Borrowings

Information regarding Alliant Energy’s, IPL’s and WPL’s commercial paper, and Alliant Energy’s and WPL’s borrowings under the single credit facility, which currently expires in August 2023, classified as short-term debt was as follows (dollars in millions):

June 30, 2020	Alliant Energy	IPL	WPL
Amount outstanding	$185.4	$—	$37.9
Weighted average interest rates	0.3%	N/A	0.2%
Available credit facility capacity	$814.6	$250.0	$262.1

	Alliant Energy		IPL		WPL
Three Months Ended June 30	2020	2019	2020	2019	2020	2019
Maximum amount outstanding (based on daily outstanding balances)	$270.5	$590.2	$8.4	$—	$182.0	$193.3
Average amount outstanding (based on daily outstanding balances)	$121.2	$531.7	$0.4	$—	$8.7	$141.6
Weighted average interest rates	0.5%	2.7%	0.5%	N/A	0.5%	2.5%
Six Months Ended June 30
Maximum amount outstanding (based on daily outstanding balances)	$462.5	$600.6	$8.4	$50.4	$212.0	$195.1
Average amount outstanding (based on daily outstanding balances)	$251.8	$515.4	$0.2	$0.3	$87.9	$139.8
Weighted average interest rates	1.5%	2.7%	0.5%	2.8%	1.7%	2.5%

XML

Revenues (Tables)

6 Months Ended

Jun. 30, 2020

Disaggregation of Revenue [Line Items]

Disaggregation of Revenue

Disaggregation of revenues from contracts with customers, which correlates to revenues for each reportable segment, was as follows (in millions):

	Alliant Energy				IPL				WPL
Three Months Ended June 30	2020		2019		2020		2019		2020		2019
Electric Utility:
Retail - residential		$249.7		$233.3		$135.3		$125.9		$114.4		$107.4
Retail - commercial	164.0		171.3		109.0		111.4		55.0		59.9
Retail - industrial	197.3		214.2		114.3		118.4		83.0		95.8
Wholesale	39.1		41.0		13.0		14.6		26.1		26.4
Bulk power and other	25.1		31.4		16.8		22.0		8.3		9.4
Total Electric Utility	675.2		691.2		388.4		392.3		286.8		298.9
Gas Utility:
Retail - residential	33.6		35.2		18.5		20.0		15.1		15.2
Retail - commercial	14.7		16.1		8.3		8.8		6.4		7.3
Retail - industrial	1.7		2.0		1.3		1.6		0.4		0.4
Transportation/other	8.9		11.9		5.8		8.0		3.1		3.9
Total Gas Utility	58.9		65.2		33.9		38.4		25.0		26.8
Other Utility:
Steam	8.6		9.2		8.6		9.2		—		—
Other utility	1.5		1.7		1.0		1.3		0.5		0.4
Total Other Utility	10.1		10.9		9.6		10.5		0.5		0.4
Non-Utility and Other:
Transportation and other	18.9		22.9		—		—		—		—
Total Non-Utility and Other	18.9		22.9		—		—		—		—
Total revenues		$763.1		$790.2		$431.9		$441.2		$312.3		$326.1

	Alliant Energy				IPL				WPL
Six Months Ended June 30	2020		2019		2020		2019		2020		2019
Electric Utility:
Retail - residential		$516.5		$508.0		$282.7		$273.4		$233.8		$234.6
Retail - commercial	346.3		352.4		228.7		228.0		117.6		124.4
Retail - industrial	407.2		422.9		235.5		234.5		171.7		188.4
Wholesale	80.0		87.5		27.4		31.5		52.6		56.0
Bulk power and other	55.5		63.8		38.9		44.7		16.6		19.1
Total Electric Utility	1,405.5		1,434.6		813.2		812.1		592.3		622.5
Gas Utility:
Retail - residential	124.1		167.0		67.3		97.9		56.8		69.1
Retail - commercial	60.4		79.7		32.4		43.6		28.0		36.1
Retail - industrial	5.9		7.4		3.6		4.8		2.3		2.6
Transportation/other	20.7		26.9		13.6		16.7		7.1		10.2
Total Gas Utility	211.1		281.0		116.9		163.0		94.2		118.0
Other Utility:
Steam	18.6		17.6		18.6		17.6		—		—
Other utility	3.1		4.4		2.1		3.6		1.0		0.8
Total Other Utility	21.7		22.0		20.7		21.2		1.0		0.8
Non-Utility and Other:
Transportation and other	40.5		39.8		—		—		—		—
Total Non-Utility and Other	40.5		39.8		—		—		—		—
Total revenues		$1,678.8		$1,777.4		$950.8		$996.3		$687.5		$741.3

IPL [Member]

Disaggregation of Revenue [Line Items]

Disaggregation of Revenue

Disaggregation of revenues from contracts with customers, which correlates to revenues for each reportable segment, was as follows (in millions):

	Alliant Energy				IPL				WPL
Three Months Ended June 30	2020		2019		2020		2019		2020		2019
Electric Utility:
Retail - residential		$249.7		$233.3		$135.3		$125.9		$114.4		$107.4
Retail - commercial	164.0		171.3		109.0		111.4		55.0		59.9
Retail - industrial	197.3		214.2		114.3		118.4		83.0		95.8
Wholesale	39.1		41.0		13.0		14.6		26.1		26.4
Bulk power and other	25.1		31.4		16.8		22.0		8.3		9.4
Total Electric Utility	675.2		691.2		388.4		392.3		286.8		298.9
Gas Utility:
Retail - residential	33.6		35.2		18.5		20.0		15.1		15.2
Retail - commercial	14.7		16.1		8.3		8.8		6.4		7.3
Retail - industrial	1.7		2.0		1.3		1.6		0.4		0.4
Transportation/other	8.9		11.9		5.8		8.0		3.1		3.9
Total Gas Utility	58.9		65.2		33.9		38.4		25.0		26.8
Other Utility:
Steam	8.6		9.2		8.6		9.2		—		—
Other utility	1.5		1.7		1.0		1.3		0.5		0.4
Total Other Utility	10.1		10.9		9.6		10.5		0.5		0.4
Non-Utility and Other:
Transportation and other	18.9		22.9		—		—		—		—
Total Non-Utility and Other	18.9		22.9		—		—		—		—
Total revenues		$763.1		$790.2		$431.9		$441.2		$312.3		$326.1

	Alliant Energy				IPL				WPL
Six Months Ended June 30	2020		2019		2020		2019		2020		2019
Electric Utility:
Retail - residential		$516.5		$508.0		$282.7		$273.4		$233.8		$234.6
Retail - commercial	346.3		352.4		228.7		228.0		117.6		124.4
Retail - industrial	407.2		422.9		235.5		234.5		171.7		188.4
Wholesale	80.0		87.5		27.4		31.5		52.6		56.0
Bulk power and other	55.5		63.8		38.9		44.7		16.6		19.1
Total Electric Utility	1,405.5		1,434.6		813.2		812.1		592.3		622.5
Gas Utility:
Retail - residential	124.1		167.0		67.3		97.9		56.8		69.1
Retail - commercial	60.4		79.7		32.4		43.6		28.0		36.1
Retail - industrial	5.9		7.4		3.6		4.8		2.3		2.6
Transportation/other	20.7		26.9		13.6		16.7		7.1		10.2
Total Gas Utility	211.1		281.0		116.9		163.0		94.2		118.0
Other Utility:
Steam	18.6		17.6		18.6		17.6		—		—
Other utility	3.1		4.4		2.1		3.6		1.0		0.8
Total Other Utility	21.7		22.0		20.7		21.2		1.0		0.8
Non-Utility and Other:
Transportation and other	40.5		39.8		—		—		—		—
Total Non-Utility and Other	40.5		39.8		—		—		—		—
Total revenues		$1,678.8		$1,777.4		$950.8		$996.3		$687.5		$741.3

WPL [Member]

Disaggregation of Revenue [Line Items]

Disaggregation of Revenue

Disaggregation of revenues from contracts with customers, which correlates to revenues for each reportable segment, was as follows (in millions):

	Alliant Energy				IPL				WPL
Three Months Ended June 30	2020		2019		2020		2019		2020		2019
Electric Utility:
Retail - residential		$249.7		$233.3		$135.3		$125.9		$114.4		$107.4
Retail - commercial	164.0		171.3		109.0		111.4		55.0		59.9
Retail - industrial	197.3		214.2		114.3		118.4		83.0		95.8
Wholesale	39.1		41.0		13.0		14.6		26.1		26.4
Bulk power and other	25.1		31.4		16.8		22.0		8.3		9.4
Total Electric Utility	675.2		691.2		388.4		392.3		286.8		298.9
Gas Utility:
Retail - residential	33.6		35.2		18.5		20.0		15.1		15.2
Retail - commercial	14.7		16.1		8.3		8.8		6.4		7.3
Retail - industrial	1.7		2.0		1.3		1.6		0.4		0.4
Transportation/other	8.9		11.9		5.8		8.0		3.1		3.9
Total Gas Utility	58.9		65.2		33.9		38.4		25.0		26.8
Other Utility:
Steam	8.6		9.2		8.6		9.2		—		—
Other utility	1.5		1.7		1.0		1.3		0.5		0.4
Total Other Utility	10.1		10.9		9.6		10.5		0.5		0.4
Non-Utility and Other:
Transportation and other	18.9		22.9		—		—		—		—
Total Non-Utility and Other	18.9		22.9		—		—		—		—
Total revenues		$763.1		$790.2		$431.9		$441.2		$312.3		$326.1

	Alliant Energy				IPL				WPL
Six Months Ended June 30	2020		2019		2020		2019		2020		2019
Electric Utility:
Retail - residential		$516.5		$508.0		$282.7		$273.4		$233.8		$234.6
Retail - commercial	346.3		352.4		228.7		228.0		117.6		124.4
Retail - industrial	407.2		422.9		235.5		234.5		171.7		188.4
Wholesale	80.0		87.5		27.4		31.5		52.6		56.0
Bulk power and other	55.5		63.8		38.9		44.7		16.6		19.1
Total Electric Utility	1,405.5		1,434.6		813.2		812.1		592.3		622.5
Gas Utility:
Retail - residential	124.1		167.0		67.3		97.9		56.8		69.1
Retail - commercial	60.4		79.7		32.4		43.6		28.0		36.1
Retail - industrial	5.9		7.4		3.6		4.8		2.3		2.6
Transportation/other	20.7		26.9		13.6		16.7		7.1		10.2
Total Gas Utility	211.1		281.0		116.9		163.0		94.2		118.0
Other Utility:
Steam	18.6		17.6		18.6		17.6		—		—
Other utility	3.1		4.4		2.1		3.6		1.0		0.8
Total Other Utility	21.7		22.0		20.7		21.2		1.0		0.8
Non-Utility and Other:
Transportation and other	40.5		39.8		—		—		—		—
Total Non-Utility and Other	40.5		39.8		—		—		—		—
Total revenues		$1,678.8		$1,777.4		$950.8		$996.3		$687.5		$741.3

XML

Income Taxes (Tables)

6 Months Ended

Jun. 30, 2020

Income Taxes [Line Items]

Schedule Of Effective Income Tax Rates

Overall effective income tax rates, which were computed by dividing income tax expense (benefit) by income before income taxes, were as follows. The effective income tax rates were different than the federal statutory rate primarily due to state income taxes, production tax credits, amortization of excess deferred taxes and the effect of rate-making on property-related differences. The decreases in overall effective income tax rates for the three and six months ended June 30, 2020 compared to the same periods in 2019 were primarily due to increases in production tax credits as a result of increased wind production in 2020 and increased amortization of excess deferred taxes primarily at WPL, which were used to offset increases in WPL’s 2020 increased revenue requirements.

	Alliant Energy				IPL				WPL
	Three Months		Six Months		Three Months		Six Months		Three Months		Six Months
	2020	2019	2020	2019	2020	2019	2020	2019	2020	2019	2020	2019
Overall income tax rate	(6.5%)	10.3%	(9.6%)	10.5%	(6.5%)	3.8%	(13.8%)	3.7%	(8.5%)	15.5%	(9.4%)	17.2%

Summary Of Tax Credit Carryforwards

At June 30, 2020, carryforwards and expiration dates were estimated as follows (in millions):

	Range of Expiration Dates	Alliant Energy		IPL		WPL
Federal net operating losses	2037		$299		$276		$3
State net operating losses	2020-2040	595		9		2
Federal tax credits	2022-2040	403		212		170

IPL [Member]

Income Taxes [Line Items]

Schedule Of Effective Income Tax Rates

Overall effective income tax rates, which were computed by dividing income tax expense (benefit) by income before income taxes, were as follows. The effective income tax rates were different than the federal statutory rate primarily due to state income taxes, production tax credits, amortization of excess deferred taxes and the effect of rate-making on property-related differences. The decreases in overall effective income tax rates for the three and six months ended June 30, 2020 compared to the same periods in 2019 were primarily due to increases in production tax credits as a result of increased wind production in 2020 and increased amortization of excess deferred taxes primarily at WPL, which were used to offset increases in WPL’s 2020 increased revenue requirements.

	Alliant Energy				IPL				WPL
	Three Months		Six Months		Three Months		Six Months		Three Months		Six Months
	2020	2019	2020	2019	2020	2019	2020	2019	2020	2019	2020	2019
Overall income tax rate	(6.5%)	10.3%	(9.6%)	10.5%	(6.5%)	3.8%	(13.8%)	3.7%	(8.5%)	15.5%	(9.4%)	17.2%

Summary Of Tax Credit Carryforwards

At June 30, 2020, carryforwards and expiration dates were estimated as follows (in millions):

	Range of Expiration Dates	Alliant Energy		IPL		WPL
Federal net operating losses	2037		$299		$276		$3
State net operating losses	2020-2040	595		9		2
Federal tax credits	2022-2040	403		212		170

WPL [Member]

Income Taxes [Line Items]

Schedule Of Effective Income Tax Rates

Overall effective income tax rates, which were computed by dividing income tax expense (benefit) by income before income taxes, were as follows. The effective income tax rates were different than the federal statutory rate primarily due to state income taxes, production tax credits, amortization of excess deferred taxes and the effect of rate-making on property-related differences. The decreases in overall effective income tax rates for the three and six months ended June 30, 2020 compared to the same periods in 2019 were primarily due to increases in production tax credits as a result of increased wind production in 2020 and increased amortization of excess deferred taxes primarily at WPL, which were used to offset increases in WPL’s 2020 increased revenue requirements.

	Alliant Energy				IPL				WPL
	Three Months		Six Months		Three Months		Six Months		Three Months		Six Months
	2020	2019	2020	2019	2020	2019	2020	2019	2020	2019	2020	2019
Overall income tax rate	(6.5%)	10.3%	(9.6%)	10.5%	(6.5%)	3.8%	(13.8%)	3.7%	(8.5%)	15.5%	(9.4%)	17.2%

Summary Of Tax Credit Carryforwards

At June 30, 2020, carryforwards and expiration dates were estimated as follows (in millions):

	Range of Expiration Dates	Alliant Energy		IPL		WPL
Federal net operating losses	2037		$299		$276		$3
State net operating losses	2020-2040	595		9		2
Federal tax credits	2022-2040	403		212		170

XML

Benefit Plans (Tables)

6 Months Ended

Jun. 30, 2020

Defined Benefit Plan Disclosure [Line Items]

Net Periodic Benefit Costs

The components of net periodic benefit costs for sponsored defined benefit pension and OPEB plans for the three and six months ended June 30 are included below (in millions). For IPL and WPL, amounts represent those for their plan participants covered under plans they sponsor, as well as amounts directly assigned to them related to certain participants in the Alliant Energy and Corporate Services sponsored plans.

	Defined Benefit Pension Plans												OPEB Plans
	Three Months						Six Months						Three Months						Six Months
Alliant Energy	2020			2019			2020			2019			2020			2019			2020			2019
Service cost		$2.7			$2.4			$5.4			$4.8			$0.9			$0.9			$1.7			$1.7
Interest cost	10.8			12.4			21.6			24.9			1.7			2.1			3.5			4.2
Expected return on plan assets	(17.5		)	(15.0		)	(34.9		)	(30.0		)	(1.4		)	(1.3		)	(2.7		)	(2.5		)
Amortization of prior service credit	(0.1		)	(0.1		)	(0.3		)	(0.3		)	—			(0.1		)	—			(0.1		)
Amortization of actuarial loss	8.6			9.1			17.2			18.2			0.9			0.8			1.7			1.6
Settlement losses (a)	—			—			4.2			—			—			—			—			—
		$4.5			$8.8			$13.2			$17.6			$2.1			$2.4			$4.2			$4.9

	Defined Benefit Pension Plans												OPEB Plans
	Three Months						Six Months						Three Months						Six Months
IPL	2020			2019			2020			2019			2020			2019			2020			2019
Service cost		$1.7			$1.5			$3.4			$3.0			$0.4			$0.4			$0.7			$0.7
Interest cost	5.0			5.7			10.0			11.4			0.7			0.9			1.4			1.7
Expected return on plan assets	(8.2		)	(7.1		)	(16.3		)	(14.1		)	(0.9		)	(0.9		)	(1.9		)	(1.8		)
Amortization of prior service credit	—			—			(0.1		)	(0.1		)	—			—			—			—
Amortization of actuarial loss	3.7			4.0			7.4			7.9			0.2			0.3			0.5			0.7
		$2.2			$4.1			$4.4			$8.1			$0.4			$0.7			$0.7			$1.3

	Defined Benefit Pension Plans												OPEB Plans
	Three Months						Six Months						Three Months						Six Months
WPL	2020			2019			2020			2019			2020			2019			2020			2019
Service cost		$0.9			$0.8			$1.9			$1.7			$0.3			$0.3			$0.6			$0.6
Interest cost	4.7			5.4			9.4			10.8			0.7			0.9			1.4			1.7
Expected return on plan assets	(7.6		)	(6.6		)	(15.2		)	(13.1		)	(0.1		)	(0.2		)	(0.3		)	(0.3		)
Amortization of prior service credit	—			—			(0.1		)	(0.1		)	—			(0.1		)	—			(0.1		)
Amortization of actuarial loss	4.1			4.4			8.2			8.8			0.5			0.4			1.0			0.8
		$2.1			$4.0			$4.2			$8.1			$1.4			$1.3			$2.7			$2.7

(a) Settlement losses related to payments made to retired executives of Alliant Energy.

Recognized Compensation Expense And Income Tax Benefits

A summary of compensation expense, including amounts allocated to IPL and WPL, and the related income tax benefits recognized for share-based compensation awards for the three and six months ended June 30 was as follows (in millions):

	Alliant Energy								IPL								WPL
	Three Months				Six Months				Three Months				Six Months				Three Months				Six Months
	2020		2019		2020		2019		2020		2019		2020		2019		2020		2019		2020		2019
Compensation expense		$2.7		$3.4		$5.4		$8.1		$1.5		$1.9		$2.9		$4.5		$1.2		$1.4		$2.3		$3.2
Income tax benefits	0.8		1.0		1.5		2.3		0.4		0.5		0.8		1.3		0.3		0.4		0.6		0.9

Schedule Of Equity-based Compensation Plans Activity

For the six months ended June 30, 2020, performance shares, performance restricted stock units and restricted stock units were granted to key employees as follows. These shares and units will be paid out in shares of common stock, and are therefore accounted for as equity awards. As of June 30, 2020, 228,207 shares were included in the calculation of diluted EPS related to the nonvested equity awards.

		Weighted Average
	Grants	Grant Date Fair Value
Performance shares	55,303		$64.04
Performance restricted stock units	55,303	59.47
Restricted stock units	60,284	59.49

IPL [Member]

Defined Benefit Plan Disclosure [Line Items]

Net Periodic Benefit Costs

The components of net periodic benefit costs for sponsored defined benefit pension and OPEB plans for the three and six months ended June 30 are included below (in millions). For IPL and WPL, amounts represent those for their plan participants covered under plans they sponsor, as well as amounts directly assigned to them related to certain participants in the Alliant Energy and Corporate Services sponsored plans.

	Defined Benefit Pension Plans												OPEB Plans
	Three Months						Six Months						Three Months						Six Months
Alliant Energy	2020			2019			2020			2019			2020			2019			2020			2019
Service cost		$2.7			$2.4			$5.4			$4.8			$0.9			$0.9			$1.7			$1.7
Interest cost	10.8			12.4			21.6			24.9			1.7			2.1			3.5			4.2
Expected return on plan assets	(17.5		)	(15.0		)	(34.9		)	(30.0		)	(1.4		)	(1.3		)	(2.7		)	(2.5		)
Amortization of prior service credit	(0.1		)	(0.1		)	(0.3		)	(0.3		)	—			(0.1		)	—			(0.1		)
Amortization of actuarial loss	8.6			9.1			17.2			18.2			0.9			0.8			1.7			1.6
Settlement losses (a)	—			—			4.2			—			—			—			—			—
		$4.5			$8.8			$13.2			$17.6			$2.1			$2.4			$4.2			$4.9

	Defined Benefit Pension Plans												OPEB Plans
	Three Months						Six Months						Three Months						Six Months
IPL	2020			2019			2020			2019			2020			2019			2020			2019
Service cost		$1.7			$1.5			$3.4			$3.0			$0.4			$0.4			$0.7			$0.7
Interest cost	5.0			5.7			10.0			11.4			0.7			0.9			1.4			1.7
Expected return on plan assets	(8.2		)	(7.1		)	(16.3		)	(14.1		)	(0.9		)	(0.9		)	(1.9		)	(1.8		)
Amortization of prior service credit	—			—			(0.1		)	(0.1		)	—			—			—			—
Amortization of actuarial loss	3.7			4.0			7.4			7.9			0.2			0.3			0.5			0.7
		$2.2			$4.1			$4.4			$8.1			$0.4			$0.7			$0.7			$1.3

	Defined Benefit Pension Plans												OPEB Plans
	Three Months						Six Months						Three Months						Six Months
WPL	2020			2019			2020			2019			2020			2019			2020			2019
Service cost		$0.9			$0.8			$1.9			$1.7			$0.3			$0.3			$0.6			$0.6
Interest cost	4.7			5.4			9.4			10.8			0.7			0.9			1.4			1.7
Expected return on plan assets	(7.6		)	(6.6		)	(15.2		)	(13.1		)	(0.1		)	(0.2		)	(0.3		)	(0.3		)
Amortization of prior service credit	—			—			(0.1		)	(0.1		)	—			(0.1		)	—			(0.1		)
Amortization of actuarial loss	4.1			4.4			8.2			8.8			0.5			0.4			1.0			0.8
		$2.1			$4.0			$4.2			$8.1			$1.4			$1.3			$2.7			$2.7

(a) Settlement losses related to payments made to retired executives of Alliant Energy.

Recognized Compensation Expense And Income Tax Benefits

A summary of compensation expense, including amounts allocated to IPL and WPL, and the related income tax benefits recognized for share-based compensation awards for the three and six months ended June 30 was as follows (in millions):

	Alliant Energy								IPL								WPL
	Three Months				Six Months				Three Months				Six Months				Three Months				Six Months
	2020		2019		2020		2019		2020		2019		2020		2019		2020		2019		2020		2019
Compensation expense		$2.7		$3.4		$5.4		$8.1		$1.5		$1.9		$2.9		$4.5		$1.2		$1.4		$2.3		$3.2
Income tax benefits	0.8		1.0		1.5		2.3		0.4		0.5		0.8		1.3		0.3		0.4		0.6		0.9

Schedule Of Equity-based Compensation Plans Activity

For the six months ended June 30, 2020, performance shares, performance restricted stock units and restricted stock units were granted to key employees as follows. These shares and units will be paid out in shares of common stock, and are therefore accounted for as equity awards. As of June 30, 2020, 228,207 shares were included in the calculation of diluted EPS related to the nonvested equity awards.

		Weighted Average
	Grants	Grant Date Fair Value
Performance shares	55,303		$64.04
Performance restricted stock units	55,303	59.47
Restricted stock units	60,284	59.49

WPL [Member]

Defined Benefit Plan Disclosure [Line Items]

Net Periodic Benefit Costs

The components of net periodic benefit costs for sponsored defined benefit pension and OPEB plans for the three and six months ended June 30 are included below (in millions). For IPL and WPL, amounts represent those for their plan participants covered under plans they sponsor, as well as amounts directly assigned to them related to certain participants in the Alliant Energy and Corporate Services sponsored plans.

	Defined Benefit Pension Plans												OPEB Plans
	Three Months						Six Months						Three Months						Six Months
Alliant Energy	2020			2019			2020			2019			2020			2019			2020			2019
Service cost		$2.7			$2.4			$5.4			$4.8			$0.9			$0.9			$1.7			$1.7
Interest cost	10.8			12.4			21.6			24.9			1.7			2.1			3.5			4.2
Expected return on plan assets	(17.5		)	(15.0		)	(34.9		)	(30.0		)	(1.4		)	(1.3		)	(2.7		)	(2.5		)
Amortization of prior service credit	(0.1		)	(0.1		)	(0.3		)	(0.3		)	—			(0.1		)	—			(0.1		)
Amortization of actuarial loss	8.6			9.1			17.2			18.2			0.9			0.8			1.7			1.6
Settlement losses (a)	—			—			4.2			—			—			—			—			—
		$4.5			$8.8			$13.2			$17.6			$2.1			$2.4			$4.2			$4.9

	Defined Benefit Pension Plans												OPEB Plans
	Three Months						Six Months						Three Months						Six Months
IPL	2020			2019			2020			2019			2020			2019			2020			2019
Service cost		$1.7			$1.5			$3.4			$3.0			$0.4			$0.4			$0.7			$0.7
Interest cost	5.0			5.7			10.0			11.4			0.7			0.9			1.4			1.7
Expected return on plan assets	(8.2		)	(7.1		)	(16.3		)	(14.1		)	(0.9		)	(0.9		)	(1.9		)	(1.8		)
Amortization of prior service credit	—			—			(0.1		)	(0.1		)	—			—			—			—
Amortization of actuarial loss	3.7			4.0			7.4			7.9			0.2			0.3			0.5			0.7
		$2.2			$4.1			$4.4			$8.1			$0.4			$0.7			$0.7			$1.3

	Defined Benefit Pension Plans												OPEB Plans
	Three Months						Six Months						Three Months						Six Months
WPL	2020			2019			2020			2019			2020			2019			2020			2019
Service cost		$0.9			$0.8			$1.9			$1.7			$0.3			$0.3			$0.6			$0.6
Interest cost	4.7			5.4			9.4			10.8			0.7			0.9			1.4			1.7
Expected return on plan assets	(7.6		)	(6.6		)	(15.2		)	(13.1		)	(0.1		)	(0.2		)	(0.3		)	(0.3		)
Amortization of prior service credit	—			—			(0.1		)	(0.1		)	—			(0.1		)	—			(0.1		)
Amortization of actuarial loss	4.1			4.4			8.2			8.8			0.5			0.4			1.0			0.8
		$2.1			$4.0			$4.2			$8.1			$1.4			$1.3			$2.7			$2.7

(a) Settlement losses related to payments made to retired executives of Alliant Energy.

Recognized Compensation Expense And Income Tax Benefits

A summary of compensation expense, including amounts allocated to IPL and WPL, and the related income tax benefits recognized for share-based compensation awards for the three and six months ended June 30 was as follows (in millions):

	Alliant Energy								IPL								WPL
	Three Months				Six Months				Three Months				Six Months				Three Months				Six Months
	2020		2019		2020		2019		2020		2019		2020		2019		2020		2019		2020		2019
Compensation expense		$2.7		$3.4		$5.4		$8.1		$1.5		$1.9		$2.9		$4.5		$1.2		$1.4		$2.3		$3.2
Income tax benefits	0.8		1.0		1.5		2.3		0.4		0.5		0.8		1.3		0.3		0.4		0.6		0.9

Schedule Of Equity-based Compensation Plans Activity

For the six months ended June 30, 2020, performance shares, performance restricted stock units and restricted stock units were granted to key employees as follows. These shares and units will be paid out in shares of common stock, and are therefore accounted for as equity awards. As of June 30, 2020, 228,207 shares were included in the calculation of diluted EPS related to the nonvested equity awards.

		Weighted Average
	Grants	Grant Date Fair Value
Performance shares	55,303		$64.04
Performance restricted stock units	55,303	59.47
Restricted stock units	60,284	59.49

XML

Asset Retirement Obligations (Tables)

6 Months Ended

Jun. 30, 2020

Schedule of Asset Retirement Obligations [Line Items]

Reconciliation of Changes in Asset Retirement Obligations

A reconciliation of the changes in asset retirement obligations associated with long-lived assets for the six months ended June 30, 2020 is as follows (in millions):

	Alliant Energy			IPL
Balance, January 1		$196.3			$133.9
Revisions in estimated cash flows	0.9			—
Liabilities settled	(3.5		)	(2.8		)
Liabilities incurred (a)	27.6			27.6
Accretion expense	3.5			2.5
Balance, June 30		$224.8			$161.2

(a)

During the six months ended June 30, 2020, Alliant Energy and IPL recognized additional asset retirement obligations related to IPL’s newly constructed Whispering Willow North and Golden Plains wind sites. The increases in asset retirement obligations resulted in corresponding increases in property, plant and equipment, net on the respective balance sheets.

IPL [Member]

Schedule of Asset Retirement Obligations [Line Items]

Reconciliation of Changes in Asset Retirement Obligations

A reconciliation of the changes in asset retirement obligations associated with long-lived assets for the six months ended June 30, 2020 is as follows (in millions):

	Alliant Energy			IPL
Balance, January 1		$196.3			$133.9
Revisions in estimated cash flows	0.9			—
Liabilities settled	(3.5		)	(2.8		)
Liabilities incurred (a)	27.6			27.6
Accretion expense	3.5			2.5
Balance, June 30		$224.8			$161.2

(a)

During the six months ended June 30, 2020, Alliant Energy and IPL recognized additional asset retirement obligations related to IPL’s newly constructed Whispering Willow North and Golden Plains wind sites. The increases in asset retirement obligations resulted in corresponding increases in property, plant and equipment, net on the respective balance sheets.

XML

Derivative Instruments (Tables)

6 Months Ended

Jun. 30, 2020

Derivative Instruments [Line Items]

Notional Amounts Of Derivative Instruments

As of June 30, 2020, gross notional amounts and settlement/delivery years related to outstanding swap contracts, option contracts, physical forward contracts and FTRs that were accounted for as commodity derivative instruments were as follows (units in thousands):

	FTRs		Natural Gas		Coal		Diesel Fuel
	MWhs	Years	Dths	Years	Tons	Years	Gallons	Years
Alliant Energy	21,455	2020-2021	234,304	2020-2028	4,482	2020-2021	6,804	2020-2022
IPL	8,978	2020-2021	123,308	2020-2028	1,834	2020-2021	—	—
WPL	12,477	2020-2021	110,996	2020-2027	2,648	2020-2021	6,804	2020-2022

Fair Value Of Financial Instruments

Derivative instruments are recorded at fair value each reporting date on the balance sheets as assets or liabilities as follows (in millions):

	Alliant Energy				IPL				WPL
	June 30, 2020		December 31, 2019		June 30, 2020		December 31, 2019		June 30, 2020		December 31, 2019
Current derivative assets		$27.9		$15.8		$22.5		$12.1		$5.4		$3.7
Non-current derivative assets	14.5		11.0		14.5		10.2		—		0.8
Current derivative liabilities	20.0		19.0		8.5		8.9		11.5		10.1
Non-current derivative liabilities	26.2		18.6		11.8		8.5		14.4		10.1

IPL [Member]

Derivative Instruments [Line Items]

Notional Amounts Of Derivative Instruments

As of June 30, 2020, gross notional amounts and settlement/delivery years related to outstanding swap contracts, option contracts, physical forward contracts and FTRs that were accounted for as commodity derivative instruments were as follows (units in thousands):

	FTRs		Natural Gas		Coal		Diesel Fuel
	MWhs	Years	Dths	Years	Tons	Years	Gallons	Years
Alliant Energy	21,455	2020-2021	234,304	2020-2028	4,482	2020-2021	6,804	2020-2022
IPL	8,978	2020-2021	123,308	2020-2028	1,834	2020-2021	—	—
WPL	12,477	2020-2021	110,996	2020-2027	2,648	2020-2021	6,804	2020-2022

Fair Value Of Financial Instruments

Derivative instruments are recorded at fair value each reporting date on the balance sheets as assets or liabilities as follows (in millions):

	Alliant Energy				IPL				WPL
	June 30, 2020		December 31, 2019		June 30, 2020		December 31, 2019		June 30, 2020		December 31, 2019
Current derivative assets		$27.9		$15.8		$22.5		$12.1		$5.4		$3.7
Non-current derivative assets	14.5		11.0		14.5		10.2		—		0.8
Current derivative liabilities	20.0		19.0		8.5		8.9		11.5		10.1
Non-current derivative liabilities	26.2		18.6		11.8		8.5		14.4		10.1

WPL [Member]

Derivative Instruments [Line Items]

Notional Amounts Of Derivative Instruments

As of June 30, 2020, gross notional amounts and settlement/delivery years related to outstanding swap contracts, option contracts, physical forward contracts and FTRs that were accounted for as commodity derivative instruments were as follows (units in thousands):

	FTRs		Natural Gas		Coal		Diesel Fuel
	MWhs	Years	Dths	Years	Tons	Years	Gallons	Years
Alliant Energy	21,455	2020-2021	234,304	2020-2028	4,482	2020-2021	6,804	2020-2022
IPL	8,978	2020-2021	123,308	2020-2028	1,834	2020-2021	—	—
WPL	12,477	2020-2021	110,996	2020-2027	2,648	2020-2021	6,804	2020-2022

Fair Value Of Financial Instruments

Derivative instruments are recorded at fair value each reporting date on the balance sheets as assets or liabilities as follows (in millions):

	Alliant Energy				IPL				WPL
	June 30, 2020		December 31, 2019		June 30, 2020		December 31, 2019		June 30, 2020		December 31, 2019
Current derivative assets		$27.9		$15.8		$22.5		$12.1		$5.4		$3.7
Non-current derivative assets	14.5		11.0		14.5		10.2		—		0.8
Current derivative liabilities	20.0		19.0		8.5		8.9		11.5		10.1
Non-current derivative liabilities	26.2		18.6		11.8		8.5		14.4		10.1

XML

Fair Value Measurements (Tables)

6 Months Ended

Jun. 30, 2020

Statement [Line Items]

Fair Value Measurements

Carrying amounts and related estimated fair values of other financial instruments were as follows (in millions):

Alliant Energy	June 30, 2020										December 31, 2019
			Fair Value										Fair Value
	Carrying		Level		Level		Level				Carrying		Level		Level		Level
	Amount		1		2		3		Total		Amount		1		2		3		Total
Assets:
Money market fund investments		$198.3		$198.3		$—		$—		$198.3		$5.4		$5.4		$—		$—		$5.4
Derivatives	42.4		—		4.6		37.8		42.4		26.8		—		4.8		22.0		26.8
Deferred proceeds	194.1		—		—		194.1		194.1		187.7		—		—		187.7		187.7
Liabilities:
Derivatives	46.2		—		44.8		1.4		46.2		37.6		—		36.8		0.8		37.6
Long-term debt (incl. current maturities)	6,579.8		—		7,768.1		1.7		7,769.8		6,190.2		—		6,917.9		2.0		6,919.9

IPL	June 30, 2020										December 31, 2019
			Fair Value										Fair Value
	Carrying		Level		Level		Level				Carrying		Level		Level		Level
	Amount		1		2		3		Total		Amount		1		2		3		Total
Assets:
Money market fund investments		$198.3		$198.3		$—		$—		$198.3		$5.4		$5.4		$—		$—		$5.4
Derivatives	37.0		—		3.3		33.7		37.0		22.3		—		2.8		19.5		22.3
Deferred proceeds	194.1		—		—		194.1		194.1		187.7		—		—		187.7		187.7
Liabilities:
Derivatives	20.3		—		19.0		1.3		20.3		17.4		—		16.6		0.8		17.4
Long-term debt (incl. current maturities)	3,343.5		—		3,924.7		—		3,924.7		3,147.3		—		3,489.1		—		3,489.1

WPL	June 30, 2020										December 31, 2019
			Fair Value										Fair Value
	Carrying		Level		Level		Level				Carrying		Level		Level		Level
	Amount		1		2		3		Total		Amount		1		2		3		Total
Assets:
Derivatives		$5.4		$—		$1.3		$4.1		$5.4		$4.5		$—		$2.0		$2.5		$4.5
Liabilities:
Derivatives	25.9		—		25.8		0.1		25.9		20.2		—		20.2		—		20.2
Long-term debt (incl. current maturities)	2,129.4		—		2,657.2		—		2,657.2		1,932.7		—		2,268.2		—		2,268.2

Fair Value Measurements Using Significant Unobservable Inputs

Information for Alliant Energy’s and IPL’s fair value measurements using significant unobservable inputs (Level 3 inputs) was as follows (in millions). Such amounts for WPL were not material.

Alliant Energy	Commodity Contract Derivative
	Assets and (Liabilities), net						Deferred Proceeds
Three Months Ended June 30	2020			2019			2020		2019
Beginning balance, April 1		$14.2			$0.4			$188.0		$178.3
Total net gains (losses) included in changes in net assets (realized/unrealized)	12.0			(0.1		)	—		—
Transfers out of Level 3	—			3.9			—		—
Purchases	14.0			13.8			—		—
Sales	(0.1		)	—			—		—
Settlements (a)	(3.7		)	(4.8		)	6.1		36.3
Ending balance, June 30		$36.4			$13.2			$194.1		$214.6
The amount of total net gains for the period included in changes in net assets attributable to the change in unrealized gains relating to assets and liabilities held at June 30		$11.9			$—			$—		$—

Alliant Energy	Commodity Contract Derivative
	Assets and (Liabilities), net						Deferred Proceeds
Six Months Ended June 30	2020			2019			2020		2019
Beginning balance, January 1		$21.2			$12.2			$187.7		$119.4
Total net gains (losses) included in changes in net assets (realized/unrealized)	9.0			(5.7		)	—		—
Transfers out of Level 3	—			3.9			—		—
Purchases	14.0			13.8			—		—
Sales	(0.2		)	(0.2		)	—		—
Settlements (a)	(7.6		)	(10.8		)	6.4		95.2
Ending balance, June 30		$36.4			$13.2			$194.1		$214.6
The amount of total net gains (losses) for the period included in changes in net assets attributable to the change in unrealized gains (losses) relating to assets and liabilities held at June 30		$9.0			($2.6	)		$—		$—

IPL	Commodity Contract Derivative
	Assets and (Liabilities), net						Deferred Proceeds
Three Months Ended June 30	2020			2019			2020		2019
Beginning balance, April 1		$13.5			$0.6			$188.0		$178.3
Total net gains included in changes in net assets (realized/unrealized)	11.0			0.4			—		—
Transfers out of Level 3	—			2.5			—		—
Purchases	10.7			9.5			—		—
Sales	(0.1		)	—			—		—
Settlements (a)	(2.7		)	(3.7		)	6.1		36.3
Ending balance, June 30		$32.4			$9.3			$194.1		$214.6
The amount of total net gains for the period included in changes in net assets attributable to the change in unrealized gains relating to assets and liabilities held at June 30		$11.0			$0.5			$—		$—

IPL	Commodity Contract Derivative
	Assets and (Liabilities), net						Deferred Proceeds
Six Months Ended June 30	2020			2019			2020		2019
Beginning balance, January 1		$18.7			$9.0			$187.7		$119.4
Total net gains (losses) included in changes in net assets (realized/unrealized)	8.8			(2.8		)	—		—
Transfers out of Level 3	—			2.5			—		—
Purchases	10.7			9.5			—		—
Sales	(0.2		)	(0.1		)	—		—
Settlements (a)	(5.6		)	(8.8		)	6.4		95.2
Ending balance, June 30		$32.4			$9.3			$194.1		$214.6
The amount of total net gains (losses) for the period included in changes in net assets attributable to the change in unrealized gains (losses) relating to assets and liabilities held at June 30		$8.8			($0.9	)		$—		$—

(a) Settlements related to deferred proceeds are due to the change in the carrying amount of receivables sold less the allowance for doubtful accounts associated with the receivables sold and cash amounts received from the receivables sold.

Fair Value Of Net Derivative Assets

The fair value of FTR and natural gas commodity contracts categorized as Level 3 was recognized as net derivative assets as follows (in millions):

	Alliant Energy				IPL				WPL
	Excluding FTRs		FTRs		Excluding FTRs		FTRs		Excluding FTRs		FTRs
June 30, 2020		$19.3		$17.1		$18.6		$13.8		$0.7		$3.3
December 31, 2019	14.6		6.6		13.6		5.1		1.0		1.5

IPL [Member]

Statement [Line Items]

Fair Value Measurements

Carrying amounts and related estimated fair values of other financial instruments were as follows (in millions):

Alliant Energy	June 30, 2020										December 31, 2019
			Fair Value										Fair Value
	Carrying		Level		Level		Level				Carrying		Level		Level		Level
	Amount		1		2		3		Total		Amount		1		2		3		Total
Assets:
Money market fund investments		$198.3		$198.3		$—		$—		$198.3		$5.4		$5.4		$—		$—		$5.4
Derivatives	42.4		—		4.6		37.8		42.4		26.8		—		4.8		22.0		26.8
Deferred proceeds	194.1		—		—		194.1		194.1		187.7		—		—		187.7		187.7
Liabilities:
Derivatives	46.2		—		44.8		1.4		46.2		37.6		—		36.8		0.8		37.6
Long-term debt (incl. current maturities)	6,579.8		—		7,768.1		1.7		7,769.8		6,190.2		—		6,917.9		2.0		6,919.9

IPL	June 30, 2020										December 31, 2019
			Fair Value										Fair Value
	Carrying		Level		Level		Level				Carrying		Level		Level		Level
	Amount		1		2		3		Total		Amount		1		2		3		Total
Assets:
Money market fund investments		$198.3		$198.3		$—		$—		$198.3		$5.4		$5.4		$—		$—		$5.4
Derivatives	37.0		—		3.3		33.7		37.0		22.3		—		2.8		19.5		22.3
Deferred proceeds	194.1		—		—		194.1		194.1		187.7		—		—		187.7		187.7
Liabilities:
Derivatives	20.3		—		19.0		1.3		20.3		17.4		—		16.6		0.8		17.4
Long-term debt (incl. current maturities)	3,343.5		—		3,924.7		—		3,924.7		3,147.3		—		3,489.1		—		3,489.1

WPL	June 30, 2020										December 31, 2019
			Fair Value										Fair Value
	Carrying		Level		Level		Level				Carrying		Level		Level		Level
	Amount		1		2		3		Total		Amount		1		2		3		Total
Assets:
Derivatives		$5.4		$—		$1.3		$4.1		$5.4		$4.5		$—		$2.0		$2.5		$4.5
Liabilities:
Derivatives	25.9		—		25.8		0.1		25.9		20.2		—		20.2		—		20.2
Long-term debt (incl. current maturities)	2,129.4		—		2,657.2		—		2,657.2		1,932.7		—		2,268.2		—		2,268.2

Fair Value Measurements Using Significant Unobservable Inputs

Information for Alliant Energy’s and IPL’s fair value measurements using significant unobservable inputs (Level 3 inputs) was as follows (in millions). Such amounts for WPL were not material.

Alliant Energy	Commodity Contract Derivative
	Assets and (Liabilities), net						Deferred Proceeds
Three Months Ended June 30	2020			2019			2020		2019
Beginning balance, April 1		$14.2			$0.4			$188.0		$178.3
Total net gains (losses) included in changes in net assets (realized/unrealized)	12.0			(0.1		)	—		—
Transfers out of Level 3	—			3.9			—		—
Purchases	14.0			13.8			—		—
Sales	(0.1		)	—			—		—
Settlements (a)	(3.7		)	(4.8		)	6.1		36.3
Ending balance, June 30		$36.4			$13.2			$194.1		$214.6
The amount of total net gains for the period included in changes in net assets attributable to the change in unrealized gains relating to assets and liabilities held at June 30		$11.9			$—			$—		$—

Alliant Energy	Commodity Contract Derivative
	Assets and (Liabilities), net						Deferred Proceeds
Six Months Ended June 30	2020			2019			2020		2019
Beginning balance, January 1		$21.2			$12.2			$187.7		$119.4
Total net gains (losses) included in changes in net assets (realized/unrealized)	9.0			(5.7		)	—		—
Transfers out of Level 3	—			3.9			—		—
Purchases	14.0			13.8			—		—
Sales	(0.2		)	(0.2		)	—		—
Settlements (a)	(7.6		)	(10.8		)	6.4		95.2
Ending balance, June 30		$36.4			$13.2			$194.1		$214.6
The amount of total net gains (losses) for the period included in changes in net assets attributable to the change in unrealized gains (losses) relating to assets and liabilities held at June 30		$9.0			($2.6	)		$—		$—

IPL	Commodity Contract Derivative
	Assets and (Liabilities), net						Deferred Proceeds
Three Months Ended June 30	2020			2019			2020		2019
Beginning balance, April 1		$13.5			$0.6			$188.0		$178.3
Total net gains included in changes in net assets (realized/unrealized)	11.0			0.4			—		—
Transfers out of Level 3	—			2.5			—		—
Purchases	10.7			9.5			—		—
Sales	(0.1		)	—			—		—
Settlements (a)	(2.7		)	(3.7		)	6.1		36.3
Ending balance, June 30		$32.4			$9.3			$194.1		$214.6
The amount of total net gains for the period included in changes in net assets attributable to the change in unrealized gains relating to assets and liabilities held at June 30		$11.0			$0.5			$—		$—

IPL	Commodity Contract Derivative
	Assets and (Liabilities), net						Deferred Proceeds
Six Months Ended June 30	2020			2019			2020		2019
Beginning balance, January 1		$18.7			$9.0			$187.7		$119.4
Total net gains (losses) included in changes in net assets (realized/unrealized)	8.8			(2.8		)	—		—
Transfers out of Level 3	—			2.5			—		—
Purchases	10.7			9.5			—		—
Sales	(0.2		)	(0.1		)	—		—
Settlements (a)	(5.6		)	(8.8		)	6.4		95.2
Ending balance, June 30		$32.4			$9.3			$194.1		$214.6
The amount of total net gains (losses) for the period included in changes in net assets attributable to the change in unrealized gains (losses) relating to assets and liabilities held at June 30		$8.8			($0.9	)		$—		$—

(a) Settlements related to deferred proceeds are due to the change in the carrying amount of receivables sold less the allowance for doubtful accounts associated with the receivables sold and cash amounts received from the receivables sold.

Fair Value Of Net Derivative Assets

The fair value of FTR and natural gas commodity contracts categorized as Level 3 was recognized as net derivative assets as follows (in millions):

	Alliant Energy				IPL				WPL
	Excluding FTRs		FTRs		Excluding FTRs		FTRs		Excluding FTRs		FTRs
June 30, 2020		$19.3		$17.1		$18.6		$13.8		$0.7		$3.3
December 31, 2019	14.6		6.6		13.6		5.1		1.0		1.5

WPL [Member]

Statement [Line Items]

Fair Value Measurements

Carrying amounts and related estimated fair values of other financial instruments were as follows (in millions):

Alliant Energy	June 30, 2020										December 31, 2019
			Fair Value										Fair Value
	Carrying		Level		Level		Level				Carrying		Level		Level		Level
	Amount		1		2		3		Total		Amount		1		2		3		Total
Assets:
Money market fund investments		$198.3		$198.3		$—		$—		$198.3		$5.4		$5.4		$—		$—		$5.4
Derivatives	42.4		—		4.6		37.8		42.4		26.8		—		4.8		22.0		26.8
Deferred proceeds	194.1		—		—		194.1		194.1		187.7		—		—		187.7		187.7
Liabilities:
Derivatives	46.2		—		44.8		1.4		46.2		37.6		—		36.8		0.8		37.6
Long-term debt (incl. current maturities)	6,579.8		—		7,768.1		1.7		7,769.8		6,190.2		—		6,917.9		2.0		6,919.9

IPL	June 30, 2020										December 31, 2019
			Fair Value										Fair Value
	Carrying		Level		Level		Level				Carrying		Level		Level		Level
	Amount		1		2		3		Total		Amount		1		2		3		Total
Assets:
Money market fund investments		$198.3		$198.3		$—		$—		$198.3		$5.4		$5.4		$—		$—		$5.4
Derivatives	37.0		—		3.3		33.7		37.0		22.3		—		2.8		19.5		22.3
Deferred proceeds	194.1		—		—		194.1		194.1		187.7		—		—		187.7		187.7
Liabilities:
Derivatives	20.3		—		19.0		1.3		20.3		17.4		—		16.6		0.8		17.4
Long-term debt (incl. current maturities)	3,343.5		—		3,924.7		—		3,924.7		3,147.3		—		3,489.1		—		3,489.1

WPL	June 30, 2020										December 31, 2019
			Fair Value										Fair Value
	Carrying		Level		Level		Level				Carrying		Level		Level		Level
	Amount		1		2		3		Total		Amount		1		2		3		Total
Assets:
Derivatives		$5.4		$—		$1.3		$4.1		$5.4		$4.5		$—		$2.0		$2.5		$4.5
Liabilities:
Derivatives	25.9		—		25.8		0.1		25.9		20.2		—		20.2		—		20.2
Long-term debt (incl. current maturities)	2,129.4		—		2,657.2		—		2,657.2		1,932.7		—		2,268.2		—		2,268.2

Fair Value Of Net Derivative Assets

The fair value of FTR and natural gas commodity contracts categorized as Level 3 was recognized as net derivative assets as follows (in millions):

	Alliant Energy				IPL				WPL
	Excluding FTRs		FTRs		Excluding FTRs		FTRs		Excluding FTRs		FTRs
June 30, 2020		$19.3		$17.1		$18.6		$13.8		$0.7		$3.3
December 31, 2019	14.6		6.6		13.6		5.1		1.0		1.5

XML

Commitments And Contingencies (Tables)

6 Months Ended

Jun. 30, 2020

Commitments and Contingencies [Line Items]

Other Purchase Commitments

At June 30, 2020, the related minimum future commitments were as follows (in millions):

	Alliant Energy		IPL		WPL
Purchased power (a)		$39		$38		$1
Natural gas	1,017		536		481
Coal (b)	101		62		39
Other (c)	113		54		28
		$1,270		$690		$549

(a) Includes payments required by PPAs for capacity rights and minimum quantities of MWhs required to be purchased. As a result of an amendment to shorten the term of the DAEC PPA, Alliant Energy’s and IPL’s amounts include minimum future commitments related to IPL’s purchase of capacity and the resulting energy from DAEC through September 2020, and do not include the September 2020 buyout payment of $110 million.

(b) Corporate Services has historically entered into system-wide coal contracts on behalf of IPL and WPL that include minimum future commitments. Such commitments were assigned to IPL and WPL based on information available as of June 30, 2020 regarding expected future usage, which is subject to change.

(c)

Includes individual commitments incurred during the normal course of business that exceeded $1 million at June 30, 2020.

MGP Site Estimated Future Costs And Recorded Liabilities

At June 30, 2020, estimated future costs expected to be incurred for the investigation, remediation and monitoring of the MGP sites, as well as environmental liabilities recorded on the balance sheets for these sites, which are not discounted, were as follows (in millions). At June 30, 2020, such amounts for WPL were not material.

	Alliant Energy				IPL
Range of estimated future costs		$12	-	$29		$10	-	$24
Current and non-current environmental liabilities	16				13

IPL [Member]

Commitments and Contingencies [Line Items]

Other Purchase Commitments

At June 30, 2020, the related minimum future commitments were as follows (in millions):

	Alliant Energy		IPL		WPL
Purchased power (a)		$39		$38		$1
Natural gas	1,017		536		481
Coal (b)	101		62		39
Other (c)	113		54		28
		$1,270		$690		$549

(a) Includes payments required by PPAs for capacity rights and minimum quantities of MWhs required to be purchased. As a result of an amendment to shorten the term of the DAEC PPA, Alliant Energy’s and IPL’s amounts include minimum future commitments related to IPL’s purchase of capacity and the resulting energy from DAEC through September 2020, and do not include the September 2020 buyout payment of $110 million.

(b) Corporate Services has historically entered into system-wide coal contracts on behalf of IPL and WPL that include minimum future commitments. Such commitments were assigned to IPL and WPL based on information available as of June 30, 2020 regarding expected future usage, which is subject to change.

(c)

Includes individual commitments incurred during the normal course of business that exceeded $1 million at June 30, 2020.

MGP Site Estimated Future Costs And Recorded Liabilities

At June 30, 2020, estimated future costs expected to be incurred for the investigation, remediation and monitoring of the MGP sites, as well as environmental liabilities recorded on the balance sheets for these sites, which are not discounted, were as follows (in millions). At June 30, 2020, such amounts for WPL were not material.

	Alliant Energy				IPL
Range of estimated future costs		$12	-	$29		$10	-	$24
Current and non-current environmental liabilities	16				13

WPL [Member]

Commitments and Contingencies [Line Items]

Other Purchase Commitments

At June 30, 2020, the related minimum future commitments were as follows (in millions):

	Alliant Energy		IPL		WPL
Purchased power (a)		$39		$38		$1
Natural gas	1,017		536		481
Coal (b)	101		62		39
Other (c)	113		54		28
		$1,270		$690		$549

(a) Includes payments required by PPAs for capacity rights and minimum quantities of MWhs required to be purchased. As a result of an amendment to shorten the term of the DAEC PPA, Alliant Energy’s and IPL’s amounts include minimum future commitments related to IPL’s purchase of capacity and the resulting energy from DAEC through September 2020, and do not include the September 2020 buyout payment of $110 million.

(b) Corporate Services has historically entered into system-wide coal contracts on behalf of IPL and WPL that include minimum future commitments. Such commitments were assigned to IPL and WPL based on information available as of June 30, 2020 regarding expected future usage, which is subject to change.

(c)

Includes individual commitments incurred during the normal course of business that exceeded $1 million at June 30, 2020.

XML

Segments Of Business (Tables)

6 Months Ended

Jun. 30, 2020

Segment Reporting Information [Line Items]

Schedule Of Segments Of Business

Certain financial information relating to Alliant Energy’s, IPL’s and WPL’s business segments is as follows. Intersegment revenues were not material to their respective operations.

Alliant Energy									ATC Holdings,		Alliant
	Utility								Non-Utility,		Energy
	Electric		Gas		Other		Total		Parent and Other		Consolidated
	(in millions)
Three Months Ended June 30, 2020
Revenues		$675.2		$58.9		$10.1		$744.2		$18.9		$763.1
Operating income	152.1		7.1		1.2		160.4		7.7		168.1
Net income attributable to Alliant Energy common shareowners							117.4		17.0		134.4
Three Months Ended June 30, 2019
Revenues		$691.2		$65.2		$10.9		$767.3		$22.9		$790.2
Operating income	132.9		7.2		1.4		141.5		8.3		149.8
Net income attributable to Alliant Energy common shareowners							87.0		7.6		94.6

Alliant Energy									ATC Holdings,		Alliant
	Utility								Non-Utility,		Energy
	Electric		Gas		Other		Total		Parent and Other		Consolidated
	(in millions)
Six Months Ended June 30, 2020
Revenues		$1,405.5		$211.1		$21.7		$1,638.3		$40.5		$1,678.8
Operating income	298.3		48.7		3.9		350.9		5.5		356.4
Net income attributable to Alliant Energy common shareowners							289.6		14.8		304.4
Six Months Ended June 30, 2019
Revenues		$1,434.6		$281.0		$22.0		$1,737.6		$39.8		$1,777.4
Operating income	259.3		52.4		1.4		313.1		13.5		326.6
Net income attributable to Alliant Energy common shareowners							206.0		13.7		219.7

IPL	Electric		Gas		Other		Total
	(in millions)
Three Months Ended June 30, 2020
Revenues		$388.4		$33.9		$9.6		$431.9
Operating income	82.1		5.2		1.4		88.7
Net income available for common stock							59.8
Three Months Ended June 30, 2019
Revenues		$392.3		$38.4		$10.5		$441.2
Operating income	68.9		4.2		1.4		74.5
Net income available for common stock							45.0
Six Months Ended June 30, 2020
Revenues		$813.2		$116.9		$20.7		$950.8
Operating income	149.1		32.5		3.8		185.4
Net income available for common stock							142.4
Six Months Ended June 30, 2019
Revenues		$812.1		$163.0		$21.2		$996.3
Operating income	115.7		30.5		1.8		148.0
Net income available for common stock							98.3

WPL	Electric		Gas		Other			Total
	(in millions)
Three Months Ended June 30, 2020
Revenues		$286.8		$25.0		$0.5			$312.3
Operating income (loss)	70.0		1.9		(0.2		)	71.7
Net income								57.6
Three Months Ended June 30, 2019
Revenues		$298.9		$26.8		$0.4			$326.1
Operating income	64.0		3.0		—			67.0
Net income								42.0
Six Months Ended June 30, 2020
Revenues		$592.3		$94.2		$1.0			$687.5
Operating income	149.2		16.2		0.1			165.5
Net income								147.2
Six Months Ended June 30, 2019
Revenues		$622.5		$118.0		$0.8			$741.3
Operating income (loss)	143.6		21.9		(0.4		)	165.1
Net income								107.7

IPL [Member]

Segment Reporting Information [Line Items]

Schedule Of Segments Of Business

Certain financial information relating to Alliant Energy’s, IPL’s and WPL’s business segments is as follows. Intersegment revenues were not material to their respective operations.

Alliant Energy									ATC Holdings,		Alliant
	Utility								Non-Utility,		Energy
	Electric		Gas		Other		Total		Parent and Other		Consolidated
	(in millions)
Three Months Ended June 30, 2020
Revenues		$675.2		$58.9		$10.1		$744.2		$18.9		$763.1
Operating income	152.1		7.1		1.2		160.4		7.7		168.1
Net income attributable to Alliant Energy common shareowners							117.4		17.0		134.4
Three Months Ended June 30, 2019
Revenues		$691.2		$65.2		$10.9		$767.3		$22.9		$790.2
Operating income	132.9		7.2		1.4		141.5		8.3		149.8
Net income attributable to Alliant Energy common shareowners							87.0		7.6		94.6

Alliant Energy									ATC Holdings,		Alliant
	Utility								Non-Utility,		Energy
	Electric		Gas		Other		Total		Parent and Other		Consolidated
	(in millions)
Six Months Ended June 30, 2020
Revenues		$1,405.5		$211.1		$21.7		$1,638.3		$40.5		$1,678.8
Operating income	298.3		48.7		3.9		350.9		5.5		356.4
Net income attributable to Alliant Energy common shareowners							289.6		14.8		304.4
Six Months Ended June 30, 2019
Revenues		$1,434.6		$281.0		$22.0		$1,737.6		$39.8		$1,777.4
Operating income	259.3		52.4		1.4		313.1		13.5		326.6
Net income attributable to Alliant Energy common shareowners							206.0		13.7		219.7

IPL	Electric		Gas		Other		Total
	(in millions)
Three Months Ended June 30, 2020
Revenues		$388.4		$33.9		$9.6		$431.9
Operating income	82.1		5.2		1.4		88.7
Net income available for common stock							59.8
Three Months Ended June 30, 2019
Revenues		$392.3		$38.4		$10.5		$441.2
Operating income	68.9		4.2		1.4		74.5
Net income available for common stock							45.0
Six Months Ended June 30, 2020
Revenues		$813.2		$116.9		$20.7		$950.8
Operating income	149.1		32.5		3.8		185.4
Net income available for common stock							142.4
Six Months Ended June 30, 2019
Revenues		$812.1		$163.0		$21.2		$996.3
Operating income	115.7		30.5		1.8		148.0
Net income available for common stock							98.3

WPL	Electric		Gas		Other			Total
	(in millions)
Three Months Ended June 30, 2020
Revenues		$286.8		$25.0		$0.5			$312.3
Operating income (loss)	70.0		1.9		(0.2		)	71.7
Net income								57.6
Three Months Ended June 30, 2019
Revenues		$298.9		$26.8		$0.4			$326.1
Operating income	64.0		3.0		—			67.0
Net income								42.0
Six Months Ended June 30, 2020
Revenues		$592.3		$94.2		$1.0			$687.5
Operating income	149.2		16.2		0.1			165.5
Net income								147.2
Six Months Ended June 30, 2019
Revenues		$622.5		$118.0		$0.8			$741.3
Operating income (loss)	143.6		21.9		(0.4		)	165.1
Net income								107.7

WPL [Member]

Segment Reporting Information [Line Items]

Schedule Of Segments Of Business

Certain financial information relating to Alliant Energy’s, IPL’s and WPL’s business segments is as follows. Intersegment revenues were not material to their respective operations.

Alliant Energy									ATC Holdings,		Alliant
	Utility								Non-Utility,		Energy
	Electric		Gas		Other		Total		Parent and Other		Consolidated
	(in millions)
Three Months Ended June 30, 2020
Revenues		$675.2		$58.9		$10.1		$744.2		$18.9		$763.1
Operating income	152.1		7.1		1.2		160.4		7.7		168.1
Net income attributable to Alliant Energy common shareowners							117.4		17.0		134.4
Three Months Ended June 30, 2019
Revenues		$691.2		$65.2		$10.9		$767.3		$22.9		$790.2
Operating income	132.9		7.2		1.4		141.5		8.3		149.8
Net income attributable to Alliant Energy common shareowners							87.0		7.6		94.6

Alliant Energy									ATC Holdings,		Alliant
	Utility								Non-Utility,		Energy
	Electric		Gas		Other		Total		Parent and Other		Consolidated
	(in millions)
Six Months Ended June 30, 2020
Revenues		$1,405.5		$211.1		$21.7		$1,638.3		$40.5		$1,678.8
Operating income	298.3		48.7		3.9		350.9		5.5		356.4
Net income attributable to Alliant Energy common shareowners							289.6		14.8		304.4
Six Months Ended June 30, 2019
Revenues		$1,434.6		$281.0		$22.0		$1,737.6		$39.8		$1,777.4
Operating income	259.3		52.4		1.4		313.1		13.5		326.6
Net income attributable to Alliant Energy common shareowners							206.0		13.7		219.7

IPL	Electric		Gas		Other		Total
	(in millions)
Three Months Ended June 30, 2020
Revenues		$388.4		$33.9		$9.6		$431.9
Operating income	82.1		5.2		1.4		88.7
Net income available for common stock							59.8
Three Months Ended June 30, 2019
Revenues		$392.3		$38.4		$10.5		$441.2
Operating income	68.9		4.2		1.4		74.5
Net income available for common stock							45.0
Six Months Ended June 30, 2020
Revenues		$813.2		$116.9		$20.7		$950.8
Operating income	149.1		32.5		3.8		185.4
Net income available for common stock							142.4
Six Months Ended June 30, 2019
Revenues		$812.1		$163.0		$21.2		$996.3
Operating income	115.7		30.5		1.8		148.0
Net income available for common stock							98.3

WPL	Electric		Gas		Other			Total
	(in millions)
Three Months Ended June 30, 2020
Revenues		$286.8		$25.0		$0.5			$312.3
Operating income (loss)	70.0		1.9		(0.2		)	71.7
Net income								57.6
Three Months Ended June 30, 2019
Revenues		$298.9		$26.8		$0.4			$326.1
Operating income	64.0		3.0		—			67.0
Net income								42.0
Six Months Ended June 30, 2020
Revenues		$592.3		$94.2		$1.0			$687.5
Operating income	149.2		16.2		0.1			165.5
Net income								147.2
Six Months Ended June 30, 2019
Revenues		$622.5		$118.0		$0.8			$741.3
Operating income (loss)	143.6		21.9		(0.4		)	165.1
Net income								107.7

XML

Related Parties (Tables)

6 Months Ended

Jun. 30, 2020

Related Party Transactions [Line Items]

Services Provided, Sales Credited And Purchases

The amounts billed for services provided, sales credited and purchases for the three and six months ended June 30 were as follows (in millions):

	IPL								WPL
	Three Months				Six Months				Three Months				Six Months
	2020		2019		2020		2019		2020		2019		2020		2019
Corporate Services billings		$44		$47		$81		$90		$35		$35		$67		$68
Sales credited	10		12		25		27		2		3		4		4
Purchases billed	57		74		138		158		20		29		40		59

Net Intercompany Payables

Net intercompany payables to Corporate Services were as follows (in millions):

	IPL		WPL
	June 30, 2020	December 31, 2019	June 30, 2020	December 31, 2019
Net payables to Corporate Services	$93	$112	$65	$85

Related Amounts Billed Between Parties

The related amounts billed between the parties for the three and six months ended June 30 were as follows (in millions):

	Three Months				Six Months
	2020		2019		2020		2019
ATC billings to WPL		$25		$27		$53		$54
WPL billings to ATC	3		3		6		7

IPL [Member]

Related Party Transactions [Line Items]

Services Provided, Sales Credited And Purchases

The amounts billed for services provided, sales credited and purchases for the three and six months ended June 30 were as follows (in millions):

	IPL								WPL
	Three Months				Six Months				Three Months				Six Months
	2020		2019		2020		2019		2020		2019		2020		2019
Corporate Services billings		$44		$47		$81		$90		$35		$35		$67		$68
Sales credited	10		12		25		27		2		3		4		4
Purchases billed	57		74		138		158		20		29		40		59

Net Intercompany Payables

Net intercompany payables to Corporate Services were as follows (in millions):

	IPL		WPL
	June 30, 2020	December 31, 2019	June 30, 2020	December 31, 2019
Net payables to Corporate Services	$93	$112	$65	$85

WPL [Member]

Related Party Transactions [Line Items]

Services Provided, Sales Credited And Purchases

The amounts billed for services provided, sales credited and purchases for the three and six months ended June 30 were as follows (in millions):

	IPL								WPL
	Three Months				Six Months				Three Months				Six Months
	2020		2019		2020		2019		2020		2019		2020		2019
Corporate Services billings		$44		$47		$81		$90		$35		$35		$67		$68
Sales credited	10		12		25		27		2		3		4		4
Purchases billed	57		74		138		158		20		29		40		59

Net Intercompany Payables

Net intercompany payables to Corporate Services were as follows (in millions):

	IPL		WPL
	June 30, 2020	December 31, 2019	June 30, 2020	December 31, 2019
Net payables to Corporate Services	$93	$112	$65	$85

Related Amounts Billed Between Parties

The related amounts billed between the parties for the three and six months ended June 30 were as follows (in millions):

	Three Months				Six Months
	2020		2019		2020		2019
ATC billings to WPL		$25		$27		$53		$54
WPL billings to ATC	3		3		6		7

XML

Summary Of Significant Accounting Policies (Narrative) (Details) - USD ($) $ in Millions	Jun. 30, 2020	Dec. 31, 2019
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Money market fund investments	$ 198.3	$ 5.4
Money market fund investments interest rate, percentage	0.10%
IPL [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Money market fund investments	$ 198.3	5.4
Money market fund investments interest rate, percentage	0.10%
Credit Losses ASU [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
New accounting standard, cumulative effect adjustment to retained earnings, pre-tax		12.0
New accounting standard, cumulative effect adjustment to retained earnings, after-tax		$ 8.7

XML

Regulatory Matters (Narrative) (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
	Jun. 30, 2020	Jun. 30, 2020	Jun. 30, 2019
Regulatory Matters [Line Items]
Credits issued to customers		$ (63.4)	$ (26.1)
Electric transmission cost recovery [Member] | IPL [Member]
Regulatory Matters [Line Items]
Credits issued to customers	$ 42.0

XML

Regulatory Matters (Regulatory Assets) (Details) - USD ($) $ in Millions	Jun. 30, 2020	Dec. 31, 2019
Regulatory Assets [Line Items]
Regulatory assets	$ 1,843.0	$ 1,844.7
Tax-related [Member]
Regulatory Assets [Line Items]
Regulatory assets	842.5	817.6
Pension and OPEB costs [Member]
Regulatory Assets [Line Items]
Regulatory assets	501.2	524.0
Assets retired early [Member]
Regulatory Assets [Line Items]
Regulatory assets	122.9	134.0
Asset retirement obligations [Member]
Regulatory Assets [Line Items]
Regulatory assets	114.0	111.8
IPL's DAEC PPA amendment [Member]
Regulatory Assets [Line Items]
Regulatory assets	109.4	108.2
Derivatives [Member]
Regulatory Assets [Line Items]
Regulatory assets	47.0	39.5
Emission allowances [Member]
Regulatory Assets [Line Items]
Regulatory assets	19.8	21.1
Other [Member]
Regulatory Assets [Line Items]
Regulatory assets	86.2	88.5
IPL [Member]
Regulatory Assets [Line Items]
Regulatory assets	1,404.9	1,399.3
IPL [Member] | Tax-related [Member]
Regulatory Assets [Line Items]
Regulatory assets	797.4	776.8
IPL [Member] | Pension and OPEB costs [Member]
Regulatory Assets [Line Items]
Regulatory assets	251.3	262.5
IPL [Member] | Assets retired early [Member]
Regulatory Assets [Line Items]
Regulatory assets	81.8	87.9
IPL [Member] | Asset retirement obligations [Member]
Regulatory Assets [Line Items]
Regulatory assets	78.2	76.2
IPL [Member] | IPL's DAEC PPA amendment [Member]
Regulatory Assets [Line Items]
Regulatory assets	109.4	108.2
IPL [Member] | Derivatives [Member]
Regulatory Assets [Line Items]
Regulatory assets	20.5	18.3
IPL [Member] | Emission allowances [Member]
Regulatory Assets [Line Items]
Regulatory assets	19.8	21.1
IPL [Member] | Other [Member]
Regulatory Assets [Line Items]
Regulatory assets	46.5	48.3
WPL [Member]
Regulatory Assets [Line Items]
Regulatory assets	438.1	445.4
WPL [Member] | Tax-related [Member]
Regulatory Assets [Line Items]
Regulatory assets	45.1	40.8
WPL [Member] | Pension and OPEB costs [Member]
Regulatory Assets [Line Items]
Regulatory assets	249.9	261.5
WPL [Member] | Assets retired early [Member]
Regulatory Assets [Line Items]
Regulatory assets	41.1	46.1
WPL [Member] | Asset retirement obligations [Member]
Regulatory Assets [Line Items]
Regulatory assets	35.8	35.6
WPL [Member] | Derivatives [Member]
Regulatory Assets [Line Items]
Regulatory assets	26.5	21.2
WPL [Member] | Other [Member]
Regulatory Assets [Line Items]
Regulatory assets	$ 39.7	$ 40.2

XML

Regulatory Matters (Regulatory Liabilities) (Details) - USD ($) $ in Millions	Jun. 30, 2020	Dec. 31, 2019
Regulatory Liabilities [Line Items]
Regulatory liabilities	$ 1,371.0	$ 1,423.6
Tax-related [Member]
Regulatory Liabilities [Line Items]
Regulatory liabilities	779.0	835.6
Cost of removal obligations [Member]
Regulatory Liabilities [Line Items]
Regulatory liabilities	385.8	387.7
Electric transmission cost recovery [Member]
Regulatory Liabilities [Line Items]
Regulatory liabilities	66.3	88.6
Commodity cost recovery [Member]
Regulatory Liabilities [Line Items]
Regulatory liabilities	30.1	24.2
Derivatives [Member]
Regulatory Liabilities [Line Items]
Regulatory liabilities	28.8	19.9
WPL's earnings sharing mechanism [Member]
Regulatory Liabilities [Line Items]
Regulatory liabilities	20.4	21.9
Other [Member]
Regulatory Liabilities [Line Items]
Regulatory liabilities	60.6	45.7
IPL [Member]
Regulatory Liabilities [Line Items]
Regulatory liabilities	717.9	714.7
IPL [Member] | Tax-related [Member]
Regulatory Liabilities [Line Items]
Regulatory liabilities	343.6	350.9
IPL [Member] | Cost of removal obligations [Member]
Regulatory Liabilities [Line Items]
Regulatory liabilities	256.4	257.0
IPL [Member] | Electric transmission cost recovery [Member]
Regulatory Liabilities [Line Items]
Regulatory liabilities	30.7	51.3
IPL [Member] | Commodity cost recovery [Member]
Regulatory Liabilities [Line Items]
Regulatory liabilities	14.0	8.8
IPL [Member] | Derivatives [Member]
Regulatory Liabilities [Line Items]
Regulatory liabilities	26.3	17.4
IPL [Member] | Other [Member]
Regulatory Liabilities [Line Items]
Regulatory liabilities	46.9	29.3
WPL [Member]
Regulatory Liabilities [Line Items]
Regulatory liabilities	653.1	708.9
WPL [Member] | Tax-related [Member]
Regulatory Liabilities [Line Items]
Regulatory liabilities	435.4	484.7
WPL [Member] | Cost of removal obligations [Member]
Regulatory Liabilities [Line Items]
Regulatory liabilities	129.4	130.7
WPL [Member] | Electric transmission cost recovery [Member]
Regulatory Liabilities [Line Items]
Regulatory liabilities	35.6	37.3
WPL [Member] | Commodity cost recovery [Member]
Regulatory Liabilities [Line Items]
Regulatory liabilities	16.1	15.4
WPL [Member] | Derivatives [Member]
Regulatory Liabilities [Line Items]
Regulatory liabilities	2.5	2.5
WPL [Member] | WPL's earnings sharing mechanism [Member]
Regulatory Liabilities [Line Items]
Regulatory liabilities	20.4	21.9
WPL [Member] | Other [Member]
Regulatory Liabilities [Line Items]
Regulatory liabilities	$ 13.7	$ 16.4

XML

Receivables (Narrative) (Details) - Receivables Sold [Member] - IPL [Member] $ in Millions	Jun. 30, 2020 USD ($)
Receivables [Line Items]
Available capacity	$ 89.0
Outstanding receivables past due	$ 25.1

XML

Receivables (Details of Accounts Receivable) (Details) - USD ($) $ in Millions	Jun. 30, 2020	Dec. 31, 2019
Receivables [Line Items]
Customer	$ 92.7	$ 91.6
Unbilled utility revenues	68.2	82.1
Deferred proceeds	194.1	187.7
Other	41.5	48.0
Allowance for expected credit losses	(10.0)	(7.3)
Accounts receivable, less allowance for expected credit losses	386.5	402.1
IPL [Member]
Receivables [Line Items]
Customer	0.0	0.0
Unbilled utility revenues	0.0	0.0
Deferred proceeds	194.1	187.7
Other	16.5	16.3
Allowance for expected credit losses	(1.7)	(1.2)
Accounts receivable, less allowance for expected credit losses	208.9	202.8
WPL [Member]
Receivables [Line Items]
Customer	82.4	83.5
Unbilled utility revenues	68.2	82.1
Other	24.5	31.4
Allowance for expected credit losses	(8.2)	(6.1)
Accounts receivable, less allowance for expected credit losses	$ 166.9	$ 190.9

XML

Receivables (Maximum And Average Outstanding Cash Proceeds) (Details) - IPL [Member] - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Maximum [Member]
Receivables [Line Items]
Outstanding aggregate cash proceeds (based on daily outstanding balances)	$ 65.0	$ 25.0	$ 96.0	$ 108.0
Average [Member]
Receivables [Line Items]
Outstanding aggregate cash proceeds (based on daily outstanding balances)	$ 11.1	$ 2.6	$ 17.3	$ 41.6

XML

Receivables (Receivables Sold Under The Agreement) (Details) - USD ($) $ in Millions	Jun. 30, 2020	Dec. 31, 2019
Receivables [Line Items]
Fair value of deferred proceeds	$ 194.1	$ 187.7
IPL [Member]
Receivables [Line Items]
Fair value of deferred proceeds	194.1	187.7
Receivables Sold [Member] | IPL [Member]
Receivables [Line Items]
Customer accounts receivable	113.5	124.7
Unbilled utility revenues	92.3	95.5
Other receivables	0.4	0.9
Receivables sold to third party	206.2	221.1
Less: cash proceeds	1.0	27.0
Deferred proceeds	205.2	194.1
Less: allowance for expected credit losses	11.1	6.4
Fair value of deferred proceeds	$ 194.1	$ 187.7

XML

Receivables (Additional Attributes Of Receivables Sold Under The Agreement) (Details) - IPL [Member] - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Receivables [Line Items]
Collections	$ 453.0	$ 487.7	$ 994.4	$ 1,043.5
Write-offs, net of recoveries	$ 1.2	$ 2.6	$ 3.3	$ 8.1

XML

Investments (Unconsolidated Equity Investments) (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Schedule of Equity Method Investments [Line Items]
Equity income from unconsolidated investments, net	$ (17.4)	$ (12.7)	$ (30.8)	$ (23.6)
ATC Holdings [Member]
Schedule of Equity Method Investments [Line Items]
Equity income from unconsolidated investments, net	(13.5)	(10.0)	(24.5)	(19.5)
Non-utility wind farm in Oklahoma [Member]
Schedule of Equity Method Investments [Line Items]
Equity income from unconsolidated investments, net	(1.9)	(1.3)	(4.1)	(2.4)
Other [Member]
Schedule of Equity Method Investments [Line Items]
Equity income from unconsolidated investments, net	$ (2.0)	$ (1.4)	$ (2.2)	$ (1.7)

XML

Common Equity (Narrative) (Details) - USD ($) $ / shares in Units, $ in Millions	1 Months Ended	3 Months Ended			6 Months Ended
	Nov. 30, 2019	Jun. 30, 2020	Mar. 31, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Common Equity [Line Items]
Proceeds from issuance of common stock, net		$ 6.4		$ 6.0	$ 234.8	$ 60.6
Equity Forward Agreements [Member]
Common Equity [Line Items]
Common stock to be issued, equity forward agreements (in shares)	4,275,127
Forward sales price (in dollars per share)	$ 52.235		$ 51.98
Proceeds from issuance of common stock, net			$ 222.0
Common stock issued during the period, equity forward agreements (in shares)			4,275,127		4,275,127

XML

Common Equity (Common Share Activity) (Details) - shares	3 Months Ended	6 Months Ended
	Mar. 31, 2020	Jun. 30, 2020
Common Stock Oustanding [Roll Forward]
Shares outstanding, January 1, 2020 (in shares)	245,022,800	245,022,800
Shareowner Direct Plan (in shares)		248,220
Equity-based compensation plans (in shares)		98,205
Shares outstanding, June 30, 2020 (in shares)		249,644,352
Equity Forward Agreements [Member]
Common Stock Oustanding [Roll Forward]
Equity forward agreements (in shares)	4,275,127	4,275,127

XML

Common Equity (Changes in Shareowners' Equity) (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended			6 Months Ended
	Jun. 30, 2020	Mar. 31, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Changes in Shareowners' Equity Roll Forward [Line Items]
Beginning balance		$ 5,205.1		$ 5,205.1
Beginning balance	$ 5,702.4	5,405.1	$ 4,882.4	5,405.1	$ 4,785.7
Net income attributable to common shareowners	134.4		94.6	304.4	219.7
Net income	136.9		97.1	309.5	224.8
Common stock dividends	(94.6)		(84.1)	(187.6)	(167.8)
Equity forward settlements and Shareowner Direct Plan issuances	6.4		6.0	234.8	60.6
Equity-based compensation plans and other	2.3		2.1	2.2	2.1
Adoption of new accounting standard, net of tax				(8.7)
Other comprehensive loss, net of tax	(2.6)		(1.4)	(1.9)	(0.7)
Ending balance	5,548.3			5,548.3
Ending balance	$ 5,748.3	5,702.4	$ 4,899.6	$ 5,748.3	$ 4,899.6
Common stock dividends (in dollars per share)	$ 0.38		$ 0.355	$ 0.76	$ 0.71
Common Stock [Member]
Changes in Shareowners' Equity Roll Forward [Line Items]
Beginning balance	$ 2.5	2.5	$ 2.4	$ 2.5	$ 2.4
Equity forward settlements and Shareowner Direct Plan issuances
Ending balance	2.5	2.5	2.4	2.5	2.4
Additional Paid-in Capital [Member]
Changes in Shareowners' Equity Roll Forward [Line Items]
Beginning balance	2,674.1	2,445.9	2,100.0	2,445.9	2,045.5
Equity forward settlements and Shareowner Direct Plan issuances	6.4		6.0	234.8	60.6
Equity-based compensation plans and other	2.6		2.4	2.4	2.3
Ending balance	2,683.1	2,674.1	2,108.4	2,683.1	2,108.4
Retained Earnings [Member]
Changes in Shareowners' Equity Roll Forward [Line Items]
Beginning balance	2,833.7	2,765.4	2,587.3	2,765.4	2,545.9
Net income attributable to common shareowners	134.4		94.6	304.4	219.7
Common stock dividends	(94.6)		(84.1)	(187.6)	(167.8)
Ending balance	2,873.5	2,833.7	2,597.8	2,873.5	2,597.8
Accumulated Other Comprehensive Income (Loss) [Member]
Changes in Shareowners' Equity Roll Forward [Line Items]
Beginning balance	2.0	1.3	2.4	1.3	1.7
Other comprehensive loss, net of tax	(2.6)		(1.4)	(1.9)	(0.7)
Ending balance	(0.6)	2.0	1.0	(0.6)	1.0
Shares in Deferred Compensation Trust [Member]
Changes in Shareowners' Equity Roll Forward [Line Items]
Beginning balance	(9.9)	(10.0)	(9.7)	(10.0)	(9.8)
Equity-based compensation plans and other	(0.3)		(0.3)	(0.2)	(0.2)
Ending balance	(10.2)	(9.9)	(10.0)	(10.2)	(10.0)
Cumulative Preferred Stock [Member]
Changes in Shareowners' Equity Roll Forward [Line Items]
Beginning balance	200.0	200.0	200.0	200.0	200.0
Ending balance	200.0	200.0	200.0	200.0	200.0
IPL [Member]
Changes in Shareowners' Equity Roll Forward [Line Items]
Beginning balance		3,271.8		3,271.8
Beginning balance	3,595.4	3,471.8	3,342.0	3,471.8	3,230.7
Net income attributable to common shareowners	59.8		45.0	142.4	98.3
Net income	62.3		47.5	147.5	103.4
Common stock dividends	(59.1)		(41.9)	(118.1)	(83.9)
Capital contributions from parent	75.0			175.0	100.0
Ending balance	3,471.1			3,471.1
Ending balance	3,671.1	3,595.4	3,345.1	3,671.1	3,345.1
IPL [Member] | Common Stock [Member]
Changes in Shareowners' Equity Roll Forward [Line Items]
Beginning balance	33.4	33.4	33.4	33.4	33.4
Ending balance	33.4	33.4	33.4	33.4	33.4
IPL [Member] | Additional Paid-in Capital [Member]
Changes in Shareowners' Equity Roll Forward [Line Items]
Beginning balance	2,447.8	2,347.8	2,322.8	2,347.8	2,222.8
Capital contributions from parent	75.0			175.0	100.0
Ending balance	2,522.8	2,447.8	2,322.8	2,522.8	2,322.8
IPL [Member] | Retained Earnings [Member]
Changes in Shareowners' Equity Roll Forward [Line Items]
Beginning balance	914.2	890.6	785.8	890.6	774.5
Net income attributable to common shareowners	59.8		45.0	142.4	98.3
Common stock dividends	(59.1)		(41.9)	(118.1)	(83.9)
Ending balance	914.9	914.2	788.9	914.9	788.9
IPL [Member] | Cumulative Preferred Stock [Member]
Changes in Shareowners' Equity Roll Forward [Line Items]
Beginning balance	200.0	200.0	200.0	200.0	200.0
Ending balance	200.0	200.0	200.0	200.0	200.0
WPL [Member]
Changes in Shareowners' Equity Roll Forward [Line Items]
Beginning balance		2,363.6		2,363.6
Beginning balance	2,436.1	2,363.6	2,179.2	2,363.6	2,149.5
Net income	57.6		42.0	147.2	107.7
Common stock dividends	(41.9)		(36.0)	(84.0)	(72.0)
Capital contributions from parent				25.0	0.0
Ending balance	2,451.8			2,451.8
Ending balance	2,451.8	2,436.1	2,185.2	2,451.8	2,185.2
WPL [Member] | Common Stock [Member]
Changes in Shareowners' Equity Roll Forward [Line Items]
Beginning balance	66.2	66.2	66.2	66.2	66.2
Ending balance	66.2	66.2	66.2	66.2	66.2
WPL [Member] | Additional Paid-in Capital [Member]
Changes in Shareowners' Equity Roll Forward [Line Items]
Beginning balance	1,459.0	1,434.0	1,309.0	1,434.0	1,309.0
Capital contributions from parent				25.0
Ending balance	1,459.0	1,459.0	1,309.0	1,459.0	1,309.0
WPL [Member] | Retained Earnings [Member]
Changes in Shareowners' Equity Roll Forward [Line Items]
Beginning balance	910.9	863.4	804.0	863.4	774.3
Net income	57.6		42.0	147.2	107.7
Common stock dividends	(41.9)		(36.0)	(84.0)	(72.0)
Ending balance	$ 926.6	$ 910.9	$ 810.0	926.6	$ 810.0
Credit Losses ASU [Member] | Retained Earnings [Member]
Changes in Shareowners' Equity Roll Forward [Line Items]
Adoption of new accounting standard, net of tax				$ (8.7)

XML

Debt (Narrative) (Details) - USD ($) $ in Millions	1 Months Ended			6 Months Ended
	Jun. 30, 2020	Apr. 30, 2020	Mar. 31, 2020	Jun. 30, 2020	Jun. 30, 2019
Debt [Line Items]
Payments to retire long-term debt				$ 653.7	$ 3.4
IPL [Member]
Debt [Line Items]
Payments to retire long-term debt				200.0	0.0
WPL [Member]
Debt [Line Items]
Payments to retire long-term debt				$ 150.0	$ 0.0
Term Loan Credit Agreement [Member] | Term Loan Credit Agreement Through March 2022 [Member] | Alliant Energy Finance, LLC [Member]
Debt [Line Items]
Proceeds from issuance of long-term debt			$ 300.0
Interest rate, percent	1.00%			1.00%
Term Loan Credit Agreement [Member] | Term Loan Credit Agreement Through April 2020 [Member] | Alliant Energy Finance, LLC [Member]
Debt [Line Items]
Payments to retire long-term debt			$ 300.0
Debentures [Member] | 3.65% debenture, due 2050 [Member] | WPL [Member]
Debt [Line Items]
Proceeds from issuance of long-term debt		$ 350.0
Interest rate, percent		3.65%
Debentures [Member] | 4.6% debenture, due 2020 [Member] | WPL [Member]
Debt [Line Items]
Interest rate, percent	4.60%			4.60%
Payments to retire long-term debt	$ 150.0
Senior Debentures [Member] | 2.3% senior debenture, due 2030 [Member] | IPL [Member]
Debt [Line Items]
Proceeds from issuance of long-term debt	$ 400.0
Interest rate, percent	2.30%			2.30%
Senior Debentures [Member] | 3.65% senior debenture, due 2020 [Member] | IPL [Member]
Debt [Line Items]
Interest rate, percent	3.65%			3.65%
Payments to retire long-term debt	$ 200.0

XML

Debt (Credit Facilities) (Details) $ in Millions	Jun. 30, 2020 USD ($)
Debt [Line Items]
Amount outstanding	$ 185.4
Weighted average interest rates	0.30%
Available credit facility capacity	$ 814.6
IPL [Member]
Debt [Line Items]
Amount outstanding	0.0
Available credit facility capacity	250.0
WPL [Member]
Debt [Line Items]
Amount outstanding	$ 37.9
Weighted average interest rates	0.20%
Available credit facility capacity	$ 262.1

XML

Debt (Other Short-Term Borrowings) (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Debt [Line Items]
Maximum amount outstanding (based on daily outstanding balances)	$ 270.5	$ 590.2	$ 462.5	$ 600.6
Average amount outstanding (based on daily outstanding balances)	$ 121.2	$ 531.7	$ 251.8	$ 515.4
Weighted average interest rates	0.50%	2.70%	1.50%	2.70%
IPL [Member]
Debt [Line Items]
Maximum amount outstanding (based on daily outstanding balances)	$ 8.4	$ 0.0	$ 8.4	$ 50.4
Average amount outstanding (based on daily outstanding balances)	$ 0.4	0.0	$ 0.2	$ 0.3
Weighted average interest rates	0.50%		0.50%	2.80%
WPL [Member]
Debt [Line Items]
Maximum amount outstanding (based on daily outstanding balances)	$ 182.0	193.3	$ 212.0	$ 195.1
Average amount outstanding (based on daily outstanding balances)	$ 8.7	$ 141.6	$ 87.9	$ 139.8
Weighted average interest rates	0.50%	2.50%	1.70%	2.50%

XML

Revenue (Disaggregation of Revenues) (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	$ 763.1	$ 790.2	$ 1,678.8	$ 1,777.4
Electric [Member]
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	675.2	691.2	1,405.5	1,434.6
Electric [Member] | Retail - residential [Member]
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	249.7	233.3	516.5	508.0
Electric [Member] | Retail - commercial [Member]
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	164.0	171.3	346.3	352.4
Electric [Member] | Retail - industrial [Member]
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	197.3	214.2	407.2	422.9
Electric [Member] | Wholesale [Member]
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	39.1	41.0	80.0	87.5
Electric [Member] | Other [Member]
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	25.1	31.4	55.5	63.8
Gas [Member]
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	58.9	65.2	211.1	281.0
Gas [Member] | Retail - residential [Member]
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	33.6	35.2	124.1	167.0
Gas [Member] | Retail - commercial [Member]
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	14.7	16.1	60.4	79.7
Gas [Member] | Retail - industrial [Member]
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	1.7	2.0	5.9	7.4
Gas [Member] | Other [Member]
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	8.9	11.9	20.7	26.9
Other Utility [Member]
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	10.1	10.9	21.7	22.0
Other Utility [Member] | Steam [Member]
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	8.6	9.2	18.6	17.6
Other Utility [Member] | Other [Member]
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	1.5	1.7	3.1	4.4
Non-utility and Other [Member]
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	18.9	22.9	40.5	39.8
Non-utility and Other [Member] | Transportation and other [Member]
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	18.9	22.9	40.5	39.8
IPL [Member]
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	431.9	441.2	950.8	996.3
IPL [Member] | Electric [Member]
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	388.4	392.3	813.2	812.1
IPL [Member] | Electric [Member] | Retail - residential [Member]
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	135.3	125.9	282.7	273.4
IPL [Member] | Electric [Member] | Retail - commercial [Member]
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	109.0	111.4	228.7	228.0
IPL [Member] | Electric [Member] | Retail - industrial [Member]
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	114.3	118.4	235.5	234.5
IPL [Member] | Electric [Member] | Wholesale [Member]
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	13.0	14.6	27.4	31.5
IPL [Member] | Electric [Member] | Other [Member]
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	16.8	22.0	38.9	44.7
IPL [Member] | Gas [Member]
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	33.9	38.4	116.9	163.0
IPL [Member] | Gas [Member] | Retail - residential [Member]
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	18.5	20.0	67.3	97.9
IPL [Member] | Gas [Member] | Retail - commercial [Member]
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	8.3	8.8	32.4	43.6
IPL [Member] | Gas [Member] | Retail - industrial [Member]
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	1.3	1.6	3.6	4.8
IPL [Member] | Gas [Member] | Other [Member]
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	5.8	8.0	13.6	16.7
IPL [Member] | Other Utility [Member]
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	9.6	10.5	20.7	21.2
IPL [Member] | Other Utility [Member] | Steam [Member]
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	8.6	9.2	18.6	17.6
IPL [Member] | Other Utility [Member] | Other [Member]
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	1.0	1.3	2.1	3.6
WPL [Member]
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	312.3	326.1	687.5	741.3
WPL [Member] | Electric [Member]
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	286.8	298.9	592.3	622.5
WPL [Member] | Electric [Member] | Retail - residential [Member]
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	114.4	107.4	233.8	234.6
WPL [Member] | Electric [Member] | Retail - commercial [Member]
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	55.0	59.9	117.6	124.4
WPL [Member] | Electric [Member] | Retail - industrial [Member]
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	83.0	95.8	171.7	188.4
WPL [Member] | Electric [Member] | Wholesale [Member]
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	26.1	26.4	52.6	56.0
WPL [Member] | Electric [Member] | Other [Member]
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	8.3	9.4	16.6	19.1
WPL [Member] | Gas [Member]
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	25.0	26.8	94.2	118.0
WPL [Member] | Gas [Member] | Retail - residential [Member]
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	15.1	15.2	56.8	69.1
WPL [Member] | Gas [Member] | Retail - commercial [Member]
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	6.4	7.3	28.0	36.1
WPL [Member] | Gas [Member] | Retail - industrial [Member]
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	0.4	0.4	2.3	2.6
WPL [Member] | Gas [Member] | Other [Member]
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	3.1	3.9	7.1	10.2
WPL [Member] | Other Utility [Member]
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	0.5	0.4	1.0	0.8
WPL [Member] | Other Utility [Member] | Other [Member]
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	$ 0.5	$ 0.4	$ 1.0	$ 0.8

XML

Income Taxes (Schedule Of Effective Income Tax Rates) (Details)	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Effective Tax Rate [Line Items]
Overall income tax rate	(6.50%)	10.30%	(9.60%)	10.50%
IPL [Member]
Effective Tax Rate [Line Items]
Overall income tax rate	(6.50%)	3.80%	(13.80%)	3.70%
WPL [Member]
Effective Tax Rate [Line Items]
Overall income tax rate	(8.50%)	15.50%	(9.40%)	17.20%

XML

Income Taxes (Summary Of Tax Credit Carryforwards) (Details) $ in Millions	Jun. 30, 2020 USD ($)
Federal [Member]
Carryforwards [Line Items]
Net operating losses, carryforward amount	$ 299
Tax credits, carryforward amount	403
Federal [Member] | IPL [Member]
Carryforwards [Line Items]
Net operating losses, carryforward amount	276
Tax credits, carryforward amount	212
Federal [Member] | WPL [Member]
Carryforwards [Line Items]
Net operating losses, carryforward amount	3
Tax credits, carryforward amount	170
State [Member]
Carryforwards [Line Items]
Net operating losses, carryforward amount	595
State [Member] | IPL [Member]
Carryforwards [Line Items]
Net operating losses, carryforward amount	9
State [Member] | WPL [Member]
Carryforwards [Line Items]
Net operating losses, carryforward amount	$ 2

XML

Benefit Plans (Narrative) (Details) $ in Millions	6 Months Ended
	Jun. 30, 2020 USD ($) shares
Defined Benefit Plan Disclosure [Line Items]
Unrecognized compensation cost	$ 9.9
Minimum [Member]
Defined Benefit Plan Disclosure [Line Items]
Unrecognized compensation cost recognized over a weighted average period	1 year
Maximum [Member]
Defined Benefit Plan Disclosure [Line Items]
Unrecognized compensation cost recognized over a weighted average period	2 years
IPL [Member]
Defined Benefit Plan Disclosure [Line Items]
Unrecognized compensation cost	$ 5.5
WPL [Member]
Defined Benefit Plan Disclosure [Line Items]
Unrecognized compensation cost	$ 4.1
Omnibus Incentive Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Shares included in diluted earnings per share (in shares) | shares	228,207

XML

Benefit Plans (Defined Benefit Pension And Other Postretirement Benefits Plans) (Details) - USD ($) $ in Millions		3 Months Ended		6 Months Ended
		Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Defined benefit pension plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost		$ 2.7	$ 2.4	$ 5.4	$ 4.8
Interest cost		10.8	12.4	21.6	24.9
Expected return on plan assets		(17.5)	(15.0)	(34.9)	(30.0)
Amortization of prior service credit		(0.1)	(0.1)	(0.3)	(0.3)
Amortization of actuarial loss		8.6	9.1	17.2	18.2
Settlement losses	[1]	0.0	0.0	4.2	0.0
Total		4.5	8.8	13.2	17.6
OPEB Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost		0.9	0.9	1.7	1.7
Interest cost		1.7	2.1	3.5	4.2
Expected return on plan assets		(1.4)	(1.3)	(2.7)	(2.5)
Amortization of prior service credit		0.0	(0.1)	0.0	(0.1)
Amortization of actuarial loss		0.9	0.8	1.7	1.6
Settlement losses		0.0	0.0	0.0	0.0
Total		2.1	2.4	4.2	4.9
IPL [Member] | Defined benefit pension plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost		1.7	1.5	3.4	3.0
Interest cost		5.0	5.7	10.0	11.4
Expected return on plan assets		(8.2)	(7.1)	(16.3)	(14.1)
Amortization of prior service credit		0.0	0.0	(0.1)	(0.1)
Amortization of actuarial loss		3.7	4.0	7.4	7.9
Total		2.2	4.1	4.4	8.1
IPL [Member] | OPEB Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost		0.4	0.4	0.7	0.7
Interest cost		0.7	0.9	1.4	1.7
Expected return on plan assets		(0.9)	(0.9)	(1.9)	(1.8)
Amortization of prior service credit		0.0	0.0	0.0	0.0
Amortization of actuarial loss		0.2	0.3	0.5	0.7
Total		0.4	0.7	0.7	1.3
WPL [Member] | Defined benefit pension plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost		0.9	0.8	1.9	1.7
Interest cost		4.7	5.4	9.4	10.8
Expected return on plan assets		(7.6)	(6.6)	(15.2)	(13.1)
Amortization of prior service credit		0.0	0.0	(0.1)	(0.1)
Amortization of actuarial loss		4.1	4.4	8.2	8.8
Total		2.1	4.0	4.2	8.1
WPL [Member] | OPEB Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost		0.3	0.3	0.6	0.6
Interest cost		0.7	0.9	1.4	1.7
Expected return on plan assets		(0.1)	(0.2)	(0.3)	(0.3)
Amortization of prior service credit		0.0	(0.1)	0.0	(0.1)
Amortization of actuarial loss		0.5	0.4	1.0	0.8
Total		$ 1.4	$ 1.3	$ 2.7	$ 2.7

[1] Settlement losses related to payments made to retired executives of Alliant Energy.

XML

Benefit Plans (Recognized Compensation Expense And Income Tax Benefits) (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Compensation expense	$ 2.7	$ 3.4	$ 5.4	$ 8.1
Income tax benefits	0.8	1.0	1.5	2.3
IPL [Member]
Compensation expense	1.5	1.9	2.9	4.5
Income tax benefits	0.4	0.5	0.8	1.3
WPL [Member]
Compensation expense	1.2	1.4	2.3	3.2
Income tax benefits	$ 0.3	$ 0.4	$ 0.6	$ 0.9

XML

Benefit Plans (Summary Of Equity-based Compensation Plans Grants) (Details)	6 Months Ended
	Jun. 30, 2020 $ / shares shares
Performance Shares [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Grants (in shares/units) | shares	55,303
Weighted average grant date fair value (in dollars per share/unit) | $ / shares	$ 64.04
Performance Restricted Stock Units [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Grants (in shares/units) | shares	55,303
Weighted average grant date fair value (in dollars per share/unit) | $ / shares	$ 59.47
Restricted Stock Units [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Grants (in shares/units) | shares	60,284
Weighted average grant date fair value (in dollars per share/unit) | $ / shares	$ 59.49

XML

Asset Retirement Obligations (Reconciliation Of Changes In Asset Retirement Obligations) (Details) $ in Millions	6 Months Ended
	Jun. 30, 2020 USD ($)
Asset Retirement Obligation, Roll Forward Analysis [Roll Forward]
Balance, January 1	$ 196.3
Revisions in estimated cash flows	0.9
Liabilities settled	(3.5)
Liabilities incurred	27.6	[1]
Accretion expense	3.5
Balance, June 30	224.8
IPL [Member]
Asset Retirement Obligation, Roll Forward Analysis [Roll Forward]
Balance, January 1	133.9
Revisions in estimated cash flows	0.0
Liabilities settled	(2.8)
Liabilities incurred	27.6	[1]
Accretion expense	2.5
Balance, June 30	$ 161.2

[1] During the six months ended June 30, 2020, Alliant Energy and IPL recognized additional asset retirement obligations related to IPL’s newly constructed Whispering Willow North and Golden Plains wind sites. The increases in asset retirement obligations resulted in corresponding increases in property, plant and equipment, net on the respective balance sheets.

XML

Derivative Instruments (Notional Amounts Of Derivative Instruments) (Details) - Commodity [Member] gal in Thousands, T in Thousands, MWh in Thousands, Dekatherms in Thousands	6 Months Ended
	Jun. 30, 2020 Dekatherms MWh T gal
FTRs (MWhs) [Member]
Notional Amount of Derivatives [Line Items]
Notional unit amount of derivatives (in MWhs) | MWh	21,455
FTRs (MWhs) [Member] | IPL [Member]
Notional Amount of Derivatives [Line Items]
Notional unit amount of derivatives (in MWhs) | MWh	8,978
FTRs (MWhs) [Member] | WPL [Member]
Notional Amount of Derivatives [Line Items]
Notional unit amount of derivatives (in MWhs) | MWh	12,477
Natural Gas (Dths) [Member]
Notional Amount of Derivatives [Line Items]
Notional unit amount of derivatives (in Dths) | Dekatherms	234,304
Natural Gas (Dths) [Member] | IPL [Member]
Notional Amount of Derivatives [Line Items]
Notional unit amount of derivatives (in Dths) | Dekatherms	123,308
Natural Gas (Dths) [Member] | WPL [Member]
Notional Amount of Derivatives [Line Items]
Notional unit amount of derivatives (in Dths) | Dekatherms	110,996
Coal (Tons) [Member]
Notional Amount of Derivatives [Line Items]
Notional unit amount of derivatives (in Tons) | T	4,482
Coal (Tons) [Member] | IPL [Member]
Notional Amount of Derivatives [Line Items]
Notional unit amount of derivatives (in Tons) | T	1,834
Coal (Tons) [Member] | WPL [Member]
Notional Amount of Derivatives [Line Items]
Notional unit amount of derivatives (in Tons) | T	2,648
Diesel Fuel (Gallons) [Member]
Notional Amount of Derivatives [Line Items]
Notional unit amount of derivatives (in Gallons) | gal	6,804
Diesel Fuel (Gallons) [Member] | IPL [Member]
Notional Amount of Derivatives [Line Items]
Notional unit amount of derivatives (in Gallons) | gal	0
Diesel Fuel (Gallons) [Member] | WPL [Member]
Notional Amount of Derivatives [Line Items]
Notional unit amount of derivatives (in Gallons) | gal	6,804

XML

Derivative Instruments (Fair Value Of Financial Instruments) (Details) - Commodity Contracts [Member] - USD ($) $ in Millions	Jun. 30, 2020	Dec. 31, 2019
Derivatives, Fair Value [Line Items]
Current derivative assets	$ 27.9	$ 15.8
Non-current derivative assets	14.5	11.0
Current derivative liabilities	20.0	19.0
Non-current derivative liabilities	26.2	18.6
IPL [Member]
Derivatives, Fair Value [Line Items]
Current derivative assets	22.5	12.1
Non-current derivative assets	14.5	10.2
Current derivative liabilities	8.5	8.9
Non-current derivative liabilities	11.8	8.5
WPL [Member]
Derivatives, Fair Value [Line Items]
Current derivative assets	5.4	3.7
Non-current derivative assets	0.0	0.8
Current derivative liabilities	11.5	10.1
Non-current derivative liabilities	$ 14.4	$ 10.1

XML

Fair Value Measurements (Fair Value Measurements) (Details) - USD ($) $ in Millions	Jun. 30, 2020	Dec. 31, 2019
Assets:
Money market fund investments	$ 198.3	$ 5.4
Deferred proceeds	194.1	187.7
Liabilities:
Long-term debt (incl. current maturities)	7,769.8	6,919.9
IPL [Member]
Assets:
Money market fund investments	198.3	5.4
Deferred proceeds	194.1	187.7
Liabilities:
Long-term debt (incl. current maturities)	3,924.7	3,489.1
WPL [Member]
Liabilities:
Long-term debt (incl. current maturities)	2,657.2	2,268.2
Commodity Contracts [Member]
Assets:
Derivatives	42.4	26.8
Liabilities:
Derivatives	46.2	37.6
Commodity Contracts [Member] | IPL [Member]
Assets:
Derivatives	37.0	22.3
Liabilities:
Derivatives	20.3	17.4
Commodity Contracts [Member] | WPL [Member]
Assets:
Derivatives	5.4	4.5
Liabilities:
Derivatives	25.9	20.2
Level 1 [Member]
Assets:
Money market fund investments	198.3	5.4
Deferred proceeds	0.0	0.0
Liabilities:
Long-term debt (incl. current maturities)	0.0	0.0
Level 1 [Member] | IPL [Member]
Assets:
Money market fund investments	198.3	5.4
Deferred proceeds	0.0	0.0
Liabilities:
Long-term debt (incl. current maturities)	0.0	0.0
Level 1 [Member] | WPL [Member]
Liabilities:
Long-term debt (incl. current maturities)	0.0	0.0
Level 1 [Member] | Commodity Contracts [Member]
Assets:
Derivatives	0.0	0.0
Liabilities:
Derivatives	0.0	0.0
Level 1 [Member] | Commodity Contracts [Member] | IPL [Member]
Assets:
Derivatives	0.0	0.0
Liabilities:
Derivatives	0.0	0.0
Level 1 [Member] | Commodity Contracts [Member] | WPL [Member]
Assets:
Derivatives	0.0	0.0
Liabilities:
Derivatives	0.0	0.0
Level 2 [Member]
Assets:
Money market fund investments	0.0	0.0
Deferred proceeds	0.0	0.0
Liabilities:
Long-term debt (incl. current maturities)	7,768.1	6,917.9
Level 2 [Member] | IPL [Member]
Assets:
Money market fund investments	0.0	0.0
Deferred proceeds	0.0	0.0
Liabilities:
Long-term debt (incl. current maturities)	3,924.7	3,489.1
Level 2 [Member] | WPL [Member]
Liabilities:
Long-term debt (incl. current maturities)	2,657.2	2,268.2
Level 2 [Member] | Commodity Contracts [Member]
Assets:
Derivatives	4.6	4.8
Liabilities:
Derivatives	44.8	36.8
Level 2 [Member] | Commodity Contracts [Member] | IPL [Member]
Assets:
Derivatives	3.3	2.8
Liabilities:
Derivatives	19.0	16.6
Level 2 [Member] | Commodity Contracts [Member] | WPL [Member]
Assets:
Derivatives	1.3	2.0
Liabilities:
Derivatives	25.8	20.2
Level 3 [Member]
Assets:
Money market fund investments	0.0	0.0
Deferred proceeds	194.1	187.7
Liabilities:
Long-term debt (incl. current maturities)	1.7	2.0
Level 3 [Member] | IPL [Member]
Assets:
Money market fund investments	0.0	0.0
Deferred proceeds	194.1	187.7
Liabilities:
Long-term debt (incl. current maturities)	0.0	0.0
Level 3 [Member] | WPL [Member]
Liabilities:
Long-term debt (incl. current maturities)	0.0	0.0
Level 3 [Member] | Commodity Contracts [Member]
Assets:
Derivatives	37.8	22.0
Liabilities:
Derivatives	1.4	0.8
Level 3 [Member] | Commodity Contracts [Member] | IPL [Member]
Assets:
Derivatives	33.7	19.5
Liabilities:
Derivatives	1.3	0.8
Level 3 [Member] | Commodity Contracts [Member] | WPL [Member]
Assets:
Derivatives	4.1	2.5
Liabilities:
Derivatives	0.1	0.0
Carrying Amount [Member]
Assets:
Money market fund investments	198.3	5.4
Deferred proceeds	194.1	187.7
Liabilities:
Long-term debt (incl. current maturities)	6,579.8	6,190.2
Carrying Amount [Member] | IPL [Member]
Assets:
Money market fund investments	198.3	5.4
Deferred proceeds	194.1	187.7
Liabilities:
Long-term debt (incl. current maturities)	3,343.5	3,147.3
Carrying Amount [Member] | WPL [Member]
Liabilities:
Long-term debt (incl. current maturities)	2,129.4	1,932.7
Carrying Amount [Member] | Commodity Contracts [Member]
Assets:
Derivatives	42.4	26.8
Liabilities:
Derivatives	46.2	37.6
Carrying Amount [Member] | Commodity Contracts [Member] | IPL [Member]
Assets:
Derivatives	37.0	22.3
Liabilities:
Derivatives	20.3	17.4
Carrying Amount [Member] | Commodity Contracts [Member] | WPL [Member]
Assets:
Derivatives	5.4	4.5
Liabilities:
Derivatives	$ 25.9	$ 20.2

XML

Fair Value Measurements (Fair Value Measurements Using Significant Unobservable Inputs) (Details) - USD ($) $ in Millions		3 Months Ended		6 Months Ended
		Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Commodity Contracts [Member]
Fair Value, Assets and Liabilities, Net, Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning balance		$ 14.2	$ 0.4	$ 21.2	$ 12.2
Total net gains (losses) included in changes in net assets (realized/unrealized)		12.0	(0.1)	9.0	(5.7)
Transfers out of Level 3		0.0	3.9	0.0	3.9
Purchases		14.0	13.8	14.0	13.8
Sales		(0.1)	0.0	(0.2)	(0.2)
Settlements		(3.7)	(4.8)	(7.6)	(10.8)
Ending balance		36.4	13.2	36.4	13.2
The amount of total net gains (losses) for the period included in changes in net assets attributable to the change in unrealized gains (losses) relating to assets and liabilities held at June 30		11.9	0.0	9.0	(2.6)
Commodity Contracts [Member] | IPL [Member]
Fair Value, Assets and Liabilities, Net, Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning balance		13.5	0.6	18.7	9.0
Total net gains (losses) included in changes in net assets (realized/unrealized)		11.0	0.4	8.8	(2.8)
Transfers out of Level 3		0.0	2.5	0.0	2.5
Purchases		10.7	9.5	10.7	9.5
Sales		(0.1)	0.0	(0.2)	(0.1)
Settlements		(2.7)	(3.7)	(5.6)	(8.8)
Ending balance		32.4	9.3	32.4	9.3
The amount of total net gains (losses) for the period included in changes in net assets attributable to the change in unrealized gains (losses) relating to assets and liabilities held at June 30		11.0	0.5	8.8	(0.9)
Deferred Proceeds [Member]
Fair Value, Assets and Liabilities, Net, Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning balance		188.0	178.3	187.7	119.4
Total net gains (losses) included in changes in net assets (realized/unrealized)		0.0	0.0	0.0	0.0
Transfers out of Level 3		0.0	0.0	0.0	0.0
Purchases		0.0	0.0	0.0	0.0
Sales		0.0	0.0	0.0	0.0
Settlements	[1]	6.1	36.3	6.4	95.2
Ending balance		194.1	214.6	194.1	214.6
The amount of total net gains (losses) for the period included in changes in net assets attributable to the change in unrealized gains (losses) relating to assets and liabilities held at June 30		0.0	0.0	0.0	0.0
Deferred Proceeds [Member] | IPL [Member]
Fair Value, Assets and Liabilities, Net, Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning balance		188.0	178.3	187.7	119.4
Total net gains (losses) included in changes in net assets (realized/unrealized)		0.0	0.0	0.0	0.0
Transfers out of Level 3		0.0	0.0	0.0	0.0
Purchases		0.0	0.0	0.0	0.0
Sales		0.0	0.0	0.0	0.0
Settlements	[1]	6.1	36.3	6.4	95.2
Ending balance		194.1	214.6	194.1	214.6
The amount of total net gains (losses) for the period included in changes in net assets attributable to the change in unrealized gains (losses) relating to assets and liabilities held at June 30		$ 0.0	$ 0.0	$ 0.0	$ 0.0

[1] Settlements related to deferred proceeds are due to the change in the carrying amount of receivables sold less the allowance for doubtful accounts associated with the receivables sold and cash amounts received from the receivables sold.

XML

Fair Value Measurements (Fair Value Of Net Derivative Assets (Liabilities)) (Details) - Commodity Contracts [Member] - USD ($) $ in Millions	Jun. 30, 2020	Mar. 31, 2020	Dec. 31, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Fair value, net derivative assets	$ 36.4	$ 14.2	$ 21.2	$ 13.2	$ 0.4	$ 12.2
Excluding Financial Transmission Rights [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Fair value, net derivative assets	19.3		14.6
Financial Transmission Rights [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Fair value, net derivative assets	17.1		6.6
IPL [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Fair value, net derivative assets	32.4	$ 13.5	18.7	$ 9.3	$ 0.6	$ 9.0
IPL [Member] | Excluding Financial Transmission Rights [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Fair value, net derivative assets	18.6		13.6
IPL [Member] | Financial Transmission Rights [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Fair value, net derivative assets	13.8		5.1
WPL [Member] | Excluding Financial Transmission Rights [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Fair value, net derivative assets	0.7		1.0
WPL [Member] | Financial Transmission Rights [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Fair value, net derivative assets	$ 3.3		$ 1.5

XML

Commitments And Contingencies (Narrative) (Details) - USD ($) $ in Millions		1 Months Ended	3 Months Ended	6 Months Ended	12 Months Ended
		May 31, 2020	Jun. 30, 2020	Jun. 30, 2020	Dec. 31, 2019
Commitments and Contingencies [Line Items]
Minimum future commitments				$ 1,270
IPL [Member]
Commitments and Contingencies [Line Items]
Minimum future commitments				690
WPL [Member]
Commitments and Contingencies [Line Items]
Minimum future commitments				549
Capital Purchase Commitment [Member]
Commitments and Contingencies [Line Items]
Minimum future commitments				60
Capital Purchase Commitment [Member] | IPL [Member]
Commitments and Contingencies [Line Items]
Minimum future commitments				8
Capital Purchase Commitment [Member] | WPL [Member]
Commitments and Contingencies [Line Items]
Minimum future commitments				52
Purchased Power [Member]
Commitments and Contingencies [Line Items]
Minimum future commitments	[1]			39
Purchased Power [Member] | IPL [Member]
Commitments and Contingencies [Line Items]
Minimum future commitments	[1]			38
Purchased Power [Member] | WPL [Member]
Commitments and Contingencies [Line Items]
Minimum future commitments	[1]			1
Indemnification Agreement [Member]
Commitments and Contingencies [Line Items]
Obligations, maximum			$ 82	82
Indemnification Agreement [Member] | IPL [Member]
Commitments and Contingencies [Line Items]
Obligations, maximum			17	17
Indemnification Agreement [Member] | Purchased Power [Member]
Commitments and Contingencies [Line Items]
Obligations, maximum			17	$ 17
Workforce Subject to Collective Bargaining Arrangements [Member]
Commitments and Contingencies [Line Items]
Employees covered by collective bargaining agreement				53.00%
Workforce Subject to Collective Bargaining Arrangements [Member] | IPL [Member]
Commitments and Contingencies [Line Items]
Employees covered by collective bargaining agreement				60.00%
Workforce Subject to Collective Bargaining Arrangements [Member] | WPL [Member]
Commitments and Contingencies [Line Items]
Employees covered by collective bargaining agreement				82.00%
Workforce Subject to Collective Bargaining Arrangements Expiring within One Year [Member]
Commitments and Contingencies [Line Items]
Employees covered by collective bargaining agreement				18.00%
Workforce Subject to Collective Bargaining Arrangements Expiring within One Year [Member] | IPL [Member]
Commitments and Contingencies [Line Items]
Employees covered by collective bargaining agreement				44.00%
Credit Losses ASU [Member]
Commitments and Contingencies [Line Items]
New accounting standard, cumulative effect adjustment to retained earnings, pre-tax					$ 12
Whiting Petroleum Affiliate [Member]
Commitments and Contingencies [Line Items]
Partnership share, percent				6.00%
Obligations, maximum			63	$ 63
Credit loss liability			20	20
Credit loss expense			0	$ 8
Whiting Petroleum Affiliate [Member] | Credit Losses ASU [Member]
Commitments and Contingencies [Line Items]
New accounting standard, cumulative effect adjustment to retained earnings, pre-tax					$ 12
FederalEnergyRegulatoryCommission [Member]
Commitments and Contingencies [Line Items]
MISO base return on equity, percentage		10.02%			9.88%
FederalEnergyRegulatoryCommission [Member] | IPL [Member]
Commitments and Contingencies [Line Items]
Refunds related to MISO base return on equity complaints			10
FederalEnergyRegulatoryCommission [Member] | WPL [Member]
Commitments and Contingencies [Line Items]
Refunds related to MISO base return on equity complaints			$ 3

[1] Includes payments required by PPAs for capacity rights and minimum quantities of MWhs required to be purchased. As a result of an amendment to shorten the term of the DAEC PPA, Alliant Energy’s and IPL’s amounts include minimum future commitments related to IPL’s purchase of capacity and the resulting energy from DAEC through September 2020, and do not include the September 2020 buyout payment of $110 million.

XML

Commitments And Contingencies (Other Purchase Commitments) (Details) - USD ($) $ in Millions		1 Months Ended	6 Months Ended
		Sep. 30, 2020	Jun. 30, 2020
Commitments and Contingencies [Line Items]
Minimum future commitments			$ 1,270
Individual commitments incurred			1
IPL [Member]
Commitments and Contingencies [Line Items]
Minimum future commitments			690
Individual commitments incurred			1
WPL [Member]
Commitments and Contingencies [Line Items]
Minimum future commitments			549
Individual commitments incurred			1
Purchased Power [Member]
Commitments and Contingencies [Line Items]
Minimum future commitments	[1]		39
Purchased Power [Member] | IPL [Member]
Commitments and Contingencies [Line Items]
Minimum future commitments	[1]		38
Purchased Power [Member] | WPL [Member]
Commitments and Contingencies [Line Items]
Minimum future commitments	[1]		1
Natural gas [Member]
Commitments and Contingencies [Line Items]
Minimum future commitments			1,017
Natural gas [Member] | IPL [Member]
Commitments and Contingencies [Line Items]
Minimum future commitments			536
Natural gas [Member] | WPL [Member]
Commitments and Contingencies [Line Items]
Minimum future commitments			481
Coal [Member]
Commitments and Contingencies [Line Items]
Minimum future commitments	[2]		101
Coal [Member] | IPL [Member]
Commitments and Contingencies [Line Items]
Minimum future commitments	[2]		62
Coal [Member] | WPL [Member]
Commitments and Contingencies [Line Items]
Minimum future commitments	[2]		39
Other [Member]
Commitments and Contingencies [Line Items]
Minimum future commitments	[3]		113
Other [Member] | IPL [Member]
Commitments and Contingencies [Line Items]
Minimum future commitments	[3]		54
Other [Member] | WPL [Member]
Commitments and Contingencies [Line Items]
Minimum future commitments	[3]		$ 28
Forecast [Member] | DAEC PPA [Member]
Commitments and Contingencies [Line Items]
Buyout payment		$ 110

[1] Includes payments required by PPAs for capacity rights and minimum quantities of MWhs required to be purchased. As a result of an amendment to shorten the term of the DAEC PPA, Alliant Energy’s and IPL’s amounts include minimum future commitments related to IPL’s purchase of capacity and the resulting energy from DAEC through September 2020, and do not include the September 2020 buyout payment of $110 million.

[2] Corporate Services has historically entered into system-wide coal contracts on behalf of IPL and WPL that include minimum future commitments. Such commitments were assigned to IPL and WPL based on information available as of June 30, 2020 regarding expected future usage, which is subject to change.

[3] Includes individual commitments incurred during the normal course of business that exceeded $1 million at June 30, 2020.

XML

Commitments And Contingencies (MPG Site Estimated Future Costs And Recorded Liabilities) (Details) - Natural Gas Processing Plant [Member] $ in Millions	6 Months Ended
	Jun. 30, 2020 USD ($)
Commitments and Contingencies [Line Items]
Current and non-current environmental liabilities	$ 16
IPL [Member]
Commitments and Contingencies [Line Items]
Current and non-current environmental liabilities	13
Minimum [Member]
Commitments and Contingencies [Line Items]
Range of estimated future costs	12
Minimum [Member] | IPL [Member]
Commitments and Contingencies [Line Items]
Range of estimated future costs	10
Maximum [Member]
Commitments and Contingencies [Line Items]
Range of estimated future costs	29
Maximum [Member] | IPL [Member]
Commitments and Contingencies [Line Items]
Range of estimated future costs	$ 24

XML

Segments Of Business (Schedule Of Segments Of Business) (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Segment Reporting Information [Line Items]
Revenues	$ 763.1	$ 790.2	$ 1,678.8	$ 1,777.4
Operating income (loss)	168.1	149.8	356.4	326.6
Net income attributable to common shareowners	134.4	94.6	304.4	219.7
Net income	136.9	97.1	309.5	224.8
IPL [Member]
Segment Reporting Information [Line Items]
Revenues	431.9	441.2	950.8	996.3
Operating income (loss)	88.7	74.5	185.4	148.0
Net income attributable to common shareowners	59.8	45.0	142.4	98.3
Net income	62.3	47.5	147.5	103.4
WPL [Member]
Segment Reporting Information [Line Items]
Revenues	312.3	326.1	687.5	741.3
Operating income (loss)	71.7	67.0	165.5	165.1
Net income	57.6	42.0	147.2	107.7
Electric [Member]
Segment Reporting Information [Line Items]
Revenues	675.2	691.2	1,405.5	1,434.6
Operating income (loss)	152.1	132.9	298.3	259.3
Electric [Member] | IPL [Member]
Segment Reporting Information [Line Items]
Revenues	388.4	392.3	813.2	812.1
Operating income (loss)	82.1	68.9	149.1	115.7
Electric [Member] | WPL [Member]
Segment Reporting Information [Line Items]
Revenues	286.8	298.9	592.3	622.5
Operating income (loss)	70.0	64.0	149.2	143.6
Gas [Member]
Segment Reporting Information [Line Items]
Revenues	58.9	65.2	211.1	281.0
Operating income (loss)	7.1	7.2	48.7	52.4
Gas [Member] | IPL [Member]
Segment Reporting Information [Line Items]
Revenues	33.9	38.4	116.9	163.0
Operating income (loss)	5.2	4.2	32.5	30.5
Gas [Member] | WPL [Member]
Segment Reporting Information [Line Items]
Revenues	25.0	26.8	94.2	118.0
Operating income (loss)	1.9	3.0	16.2	21.9
Other Utility [Member]
Segment Reporting Information [Line Items]
Revenues	10.1	10.9	21.7	22.0
Operating income (loss)	1.2	1.4	3.9	1.4
Other Utility [Member] | IPL [Member]
Segment Reporting Information [Line Items]
Revenues	9.6	10.5	20.7	21.2
Operating income (loss)	1.4	1.4	3.8	1.8
Other Utility [Member] | WPL [Member]
Segment Reporting Information [Line Items]
Revenues	0.5	0.4	1.0	0.8
Operating income (loss)	(0.2)	0.0	0.1	(0.4)
Utility Business [Member]
Segment Reporting Information [Line Items]
Revenues	744.2	767.3	1,638.3	1,737.6
Operating income (loss)	160.4	141.5	350.9	313.1
Net income attributable to common shareowners	117.4	87.0	289.6	206.0
Non-Utility [Member] | ATC Holdings, Non-Utility, Parent and Other [Member]
Segment Reporting Information [Line Items]
Revenues	18.9	22.9	40.5	39.8
Operating income (loss)	7.7	8.3	5.5	13.5
Net income attributable to common shareowners	$ 17.0	$ 7.6	$ 14.8	$ 13.7

XML

Related Parties (Narrative) (Details) - ATC LLC [Member] - Equity Method Investee [Member] - USD ($) $ in Millions	3 Months Ended
	Jun. 30, 2020	Dec. 31, 2019
WPL Owed ATC LLC [Member]
Related Party Transactions [Line Items]
Net amounts owed	$ 9	$ 9
WPL [Member]
Related Party Transactions [Line Items]
Receipt of construction deposits	$ 46

XML

Related Parties (Service Agreements) (Details) - Corporate Services [Member] - Subsidiary of Common Parent [Member] - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Corporate Services Billings [Member] | IPL [Member]
Related Party Transactions [Line Items]
Amounts billed between related parties	$ 44	$ 47	$ 81	$ 90
Corporate Services Billings [Member] | WPL [Member]
Related Party Transactions [Line Items]
Amounts billed between related parties	35	35	67	68
Sales Credited [Member] | IPL [Member]
Related Party Transactions [Line Items]
Amounts billed between related parties	10	12	25	27
Sales Credited [Member] | WPL [Member]
Related Party Transactions [Line Items]
Amounts billed between related parties	2	3	4	4
Purchases Billed [Member] | IPL [Member]
Related Party Transactions [Line Items]
Amounts billed between related parties	57	74	138	158
Purchases Billed [Member] | WPL [Member]
Related Party Transactions [Line Items]
Amounts billed between related parties	$ 20	$ 29	$ 40	$ 59

XML

Related Parties (Net Intercompany Payables) (Details) - Subsidiary of Common Parent [Member] - Corporate Services [Member] - USD ($) $ in Millions	Jun. 30, 2020	Dec. 31, 2019
IPL [Member]
Related Party Transactions [Line Items]
Net amounts owed	$ 93	$ 112
WPL [Member]
Related Party Transactions [Line Items]
Net amounts owed	$ 65	$ 85

XML

Related Parties (Amounts Billed Between Parties) (Details) - ATC LLC [Member] - Equity Method Investee [Member] - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
ATC Billings To WPL [Member]
Related Party Transactions [Line Items]
Amounts billed between related parties	$ 25	$ 27	$ 53	$ 54
WPL Billings To ATC [Member]
Related Party Transactions [Line Items]
Amounts billed between related parties	$ 3	$ 3	$ 6	$ 7