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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 September 30, 2021

or

    TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934
For the transition period from                    to                    

lnt-20210930_g1.jpg

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 registrant (1) has filed all reports required to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during the preceding 12 months (or for such shorter period that the registrant was required to file such reports), and (2) has been subject to such filing requirements for the past 90 days.
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 registrant has submitted electronically every Interactive Data File required to be submitted pursuant to Rule 405 of Regulation S-T (§232.405 of this chapter) during the preceding 12 months (or for such shorter period that the registrant was required to submit such files).
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 registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, a smaller reporting company, or an emerging growth company. See the definitions of “large accelerated filer,” “accelerated filer,” “smaller reporting company,” and “emerging growth company” in Rule 12b-2 of the Exchange Act.
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 registrant is a shell company (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 September 30, 2021:
Alliant Energy Corporation, Common Stock, $0.01 par value, 250,360,787 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
The following abbreviations or acronyms used in this report are defined below:
Abbreviation or AcronymDefinitionAbbreviation or AcronymDefinition
2020 Form 10-KCombined Annual Report on Form 10-K filed by Alliant Energy, IPL and WPL for the year ended Dec. 31, 2020GAAPU.S. generally accepted accounting principles
AEFAlliant Energy Finance, LLCIPLInterstate Power and Light Company
AFUDCAllowance for funds used during constructionIUBIowa Utilities Board
Alliant EnergyAlliant Energy CorporationMDAManagement’s Discussion and Analysis of Financial Condition and Results of Operations
ATCAmerican Transmission Company LLCMISOMidcontinent Independent System Operator, Inc.
ATC HoldingsInterest in American Transmission Company LLC and ATC Holdco LLCMWMegawatt
Corporate ServicesAlliant Energy Corporate Services, Inc.MWhMegawatt-hour
COVID-19Novel coronavirusN/ANot applicable
DAECDuane Arnold Energy CenterNote(s)Combined Notes to Condensed Consolidated Financial Statements
DthDekathermOPEBOther postretirement benefits
EGUElectric generating unitPPAPurchased power agreement
EPAU.S. Environmental Protection AgencyPSCWPublic Service Commission of Wisconsin
EPSEarnings per weighted average common shareSECSecurities and Exchange Commission
Federal Tax ReformTax Cuts and Jobs ActU.S.United States of America
FERCFederal Energy Regulatory CommissionWest RiversideWest Riverside Energy Center
Financial StatementsCondensed Consolidated Financial StatementsWhiting PetroleumWhiting Petroleum Corporation
FTRFinancial transmission rightWPLWisconsin Power and Light Company

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:

the direct or indirect effects resulting from the COVID-19 pandemic, including vaccine mandates and testing requirements, on sales volumes, margins, operations, employees, contractors, vendors, the ability to complete construction projects, supply chains, customers’ inability to pay bills, suspension of disconnects, 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 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;
the direct or indirect effects resulting from terrorist incidents, including physical attacks and cyber attacks, or responses to such incidents;
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;
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 ability to utilize tax credits and net operating losses generated to date, and those that may be generated in the future, before they expire;
1

the impacts of changes in the tax code, including tax rates, minimum tax rates, and adjustments made to deferred tax assets and liabilities;
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;
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;
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 solar generation projects within the cost targets set by regulators due to cost increases of materials, equipment and commodities including due to tariffs, labor issues or supply shortages, the ability to achieve the expected level of tax benefits based on tax guidelines and project costs, and the ability to efficiently utilize the solar generation project tax benefits for the benefit of customers;
disruptions to the supply of materials, equipment and commodities needed to construct solar generation projects, including due to shortages, labor issues or transportation issues, which may impact the ability to meet capacity requirements and result in increased capacity expense;
changes in the price of delivered natural gas, transmission, 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, excessive cold, 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, timing and form of benefits payments, 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;
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 Risk Factors in Item 1A in the 2020 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.
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PART I. FINANCIAL INFORMATION
ITEM 1. CONDENSED CONSOLIDATED FINANCIAL STATEMENTS (UNAUDITED)
ALLIANT ENERGY CORPORATION
CONDENSED CONSOLIDATED STATEMENTS OF INCOME (UNAUDITED)
For the Three MonthsFor the Nine Months
Ended September 30,Ended September 30,
2021202020212020
(in millions, except per share amounts)
Revenues:
Electric utility$939$852$2,357$2,257
Gas utility5042289253
Other utility13103632
Non-utility22166057
Total revenues1,0249202,7422,599
Operating expenses:
Electric production fuel and purchased power207179478527
Electric transmission service148132403326
Cost of gas sold1811149117
Other operation and maintenance171143477465
Depreciation and amortization165156494454
Taxes other than income taxes26277882
Total operating expenses7356482,0791,971
Operating income289272663628
Other (income) and deductions:
Interest expense6868206207
Equity income from unconsolidated investments, net(13)(15)(47)(46)
Allowance for funds used during construction(7)(13)(16)(51)
Other3377
Total other (income) and deductions5143150117
Income before income taxes238229513511
Income tax benefit(21)(20)(66)(47)
Net income259249579558
Preferred dividend requirements of Interstate Power and Light Company3388
Net income attributable to Alliant Energy common shareowners$256$246$571$550
Weighted average number of common shares outstanding:
Basic250.3249.7250.2247.9
Diluted250.8250.0250.6248.1
Earnings per weighted average common share attributable to Alliant Energy common shareowners:
Basic$1.02$0.99$2.28$2.22
Diluted$1.02$0.98$2.28$2.22

Refer to accompanying Combined Notes to Condensed Consolidated Financial Statements.
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ALLIANT ENERGY CORPORATION
CONDENSED CONSOLIDATED BALANCE SHEETS (UNAUDITED)
September 30,
2021
December 31,
2020
(in millions, except per
share and share amounts)
ASSETS
Current assets:
Cash and cash equivalents$20$54
Accounts receivable, less allowance for expected credit losses392412
Production fuel, at weighted average cost4266
Gas stored underground, at weighted average cost5846
Materials and supplies, at weighted average cost118105
Regulatory assets11181
Other274123
Total current assets1,015887
Property, plant and equipment, net14,73814,336
Investments:
ATC Holdings338331
Other176154
Total investments514485
Other assets:
Regulatory assets1,9071,929
Deferred charges and other15573
Total other assets2,0622,002
Total assets$18,329$17,710
LIABILITIES AND EQUITY
Current liabilities:
Current maturities of long-term debt$383$8
Commercial paper316389
Accounts payable361377
Regulatory liabilities231249
Other266274
Total current liabilities1,5571,297
Long-term debt, net (excluding current portion)6,6926,769
Other liabilities:
Deferred tax liabilities1,9061,814
Regulatory liabilities1,1301,057
Pension and other benefit obligations452511
Other407374
Total other liabilities3,8953,756
Commitments and contingencies (Note 14)
Equity:
Alliant Energy Corporation common equity:
Common stock - $0.01 par value - 480,000,000 shares authorized; 250,360,787 and 249,868,415 shares
32
Additional paid-in capital2,7332,704
Retained earnings3,2612,994
Accumulated other comprehensive loss(1)(1)
Shares in deferred compensation trust - 377,875 and 380,542 shares at a weighted average cost of $30.14 and $28.73 per share
(11)(11)
Total Alliant Energy Corporation common equity5,9855,688
Cumulative preferred stock of Interstate Power and Light Company200200
Total equity6,1855,888
Total liabilities and equity$18,329$17,710

Refer to accompanying Combined Notes to Condensed Consolidated Financial Statements.
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ALLIANT ENERGY CORPORATION
CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS (UNAUDITED)
For the Nine Months
Ended September 30,
20212020
(in millions)
Cash flows from operating activities:
Net income$579$558
Adjustments to reconcile net income to net cash flows from operating activities:
Depreciation and amortization
494454
Deferred tax benefit and tax credits(69)(48)
Other7(17)
Other changes in assets and liabilities:
Accounts receivable(397)(316)
Derivative assets (202)(22)
Regulatory liabilities25(72)
Deferred income taxes160143
Pension and other benefit obligations(59)(61)
DAEC PPA amendment buyout payment(110)
Other(61)(73)
Net cash flows from operating activities477436
Cash flows used for investing activities:
Construction and acquisition expenditures:
Utility business(772)(935)
Other(60)(39)
Cash receipts on sold receivables423318
Other(43)(23)
Net cash flows used for investing activities(452)(679)
Cash flows from (used for) financing activities:
Common stock dividends(304)(281)
Proceeds from issuance of common stock, net22241
Proceeds from issuance of long-term debt3001,050
Payments to retire long-term debt(4)(654)
Net change in commercial paper(73)85
Other2(22)
Net cash flows from (used for) financing activities(57)419
Net increase (decrease) in cash, cash equivalents and restricted cash(32)176
Cash, cash equivalents and restricted cash at beginning of period5618
Cash, cash equivalents and restricted cash at end of period$24$194
Supplemental cash flows information:
Cash (paid) refunded during the period for:
Interest($197)($197)
Income taxes, net($1)$6
Significant non-cash investing and financing activities:
Accrued capital expenditures$91$202
Beneficial interest obtained in exchange for securitized accounts receivable$164$201

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 MonthsFor the Nine Months
Ended September 30,Ended September 30,
2021202020212020
(in millions)
Revenues:
Electric utility$555$519$1,343$1,332
Gas utility3124165141
Steam and other13103531
Total revenues5995531,5431,504
Operating expenses:
Electric production fuel and purchased power101102215304
Electric transmission service10393274212
Cost of gas sold1268463
Other operation and maintenance9585253269
Depreciation and amortization9489281264
Taxes other than income taxes14164245
Total operating expenses4193911,1491,157
Operating income180162394347
Other (income) and deductions:
Interest expense3435103104
Allowance for funds used during construction(2)(6)(7)(21)
Other123
Total other (income) and deductions32309886
Income before income taxes148132296261
Income tax benefit(12)(19)(34)(37)
Net income160151330298
Preferred dividend requirements3388
Net income available for common stock$157$148$322$290
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.
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INTERSTATE POWER AND LIGHT COMPANY
CONDENSED CONSOLIDATED BALANCE SHEETS (UNAUDITED)
September 30,
2021
December 31,
2020
(in millions, except per
share and share amounts)
ASSETS
Current assets:
Cash and cash equivalents$13$50
Accounts receivable, less allowance for expected credit losses205210
Production fuel, at weighted average cost3248
Gas stored underground, at weighted average cost3320
Materials and supplies, at weighted average cost7163
Regulatory assets8652
Other10853
Total current assets548496
Property, plant and equipment, net7,9317,889
Other assets:
Regulatory assets1,4211,431
Deferred charges and other7833
Total other assets1,4991,464
Total assets$9,978$9,849
LIABILITIES AND EQUITY
Current liabilities:
Accounts payable$140$162
Regulatory liabilities104103
Other171182
Total current liabilities415447
Long-term debt, net3,3473,345
Other liabilities:
Deferred tax liabilities1,0791,035
Regulatory liabilities
616573
Pension and other benefit obligations161186
Other325299
Total other liabilities2,1812,093
Commitments and contingencies (Note 14)
Equity:
Interstate Power and Light Company common equity:
Common stock - $2.50 par value - 24,000,000 shares authorized; 13,370,788 shares outstanding
3333
Additional paid-in capital2,8022,752
Retained earnings1,000979
Total Interstate Power and Light Company common equity3,8353,764
Cumulative preferred stock200200
Total equity4,0353,964
Total liabilities and equity$9,978$9,849

Refer to accompanying Combined Notes to Condensed Consolidated Financial Statements.
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INTERSTATE POWER AND LIGHT COMPANY
CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS (UNAUDITED)
For the Nine Months
Ended September 30,
20212020
(in millions)
Cash flows from operating activities:
Net income$330$298
Adjustments to reconcile net income to net cash flows from operating activities:
Depreciation and amortization281264
Deferred tax benefit and tax credits(13)(42)
Other(1)(9)
Other changes in assets and liabilities:
Accounts receivable(412)(337)
Derivative assets(86)(12)
Regulatory assets(33)(32)
Regulatory liabilities30(11)
Deferred income taxes5662
Pension and other benefit obligations(25)(19)
DAEC PPA amendment buyout payment(110)
Other(32)(33)
Net cash flows from operating activities9519
Cash flows from (used for) investing activities:
Construction and acquisition expenditures(285)(465)
Cash receipts on sold receivables423318
Other(16)(55)
Net cash flows from (used for) investing activities122(202)
Cash flows from (used for) financing activities:
Common stock dividends(301)(177)
Capital contributions from parent50345
Proceeds from issuance of long-term debt400
Payments to retire long-term debt(200)
Other(3)(9)
Net cash flows from (used for) financing activities(254)359
Net increase (decrease) in cash, cash equivalents and restricted cash(37)176
Cash, cash equivalents and restricted cash at beginning of period509
Cash, cash equivalents and restricted cash at end of period$13$185
Supplemental cash flows information:
Cash (paid) refunded during the period for:
Interest($106)($109)
Income taxes, net$28($12)
Significant non-cash investing and financing activities:
Accrued capital expenditures$30$150
Beneficial interest obtained in exchange for securitized accounts receivable$164$201

Refer to accompanying Combined Notes to Condensed Consolidated Financial Statements.
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WISCONSIN POWER AND LIGHT COMPANY
CONDENSED CONSOLIDATED STATEMENTS OF INCOME (UNAUDITED)
For the Three MonthsFor the Nine Months
Ended September 30,Ended September 30,
2021202020212020
(in millions)
Revenues:
Electric utility$384$333$1,014$925
Gas utility1918124112
Other11
Total revenues4033511,1391,038
Operating expenses:
Electric production fuel and purchased power10578263223
Electric transmission service4439128114
Cost of gas sold646553
Other operation and maintenance6665194172
Depreciation and amortization7065209186
Taxes other than income taxes12113535
Total operating expenses303262894783
Operating income10089245255
Other (income) and deductions:
Interest expense25267778
Allowance for funds used during construction(5)(6)(9)(29)
Other2133
Total other (income) and deductions22217152
Income before income taxes7868174