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 2023 Form 10-K. Unless otherwise noted, all “per share” references in MDA refer to earnings per diluted share.

2024 HIGHLIGHTS

Key highlights since the filing of the 2023 Form 10-K include the following:

Customer Investments:

• In March 2024, IPL completed construction of the Duane Arnold solar facility (50 MW in Linn County, Iowa).

• In April 2024, WPL received orders from the PSCW authorizing WPL to construct improvements at the natural gas-fired Neenah Energy Facility and Sheboygan Falls Energy Facility, which would increase the capacity and efficiency of the EGUs.

• In April 2024 and June 2024, IPL and WPL entered into agreements to transfer a portion of the renewable tax credits generated in 2024 and 2025 from certain wind, solar and battery storage facilities to other corporate taxpayers in exchange for cash.

• In May 2024, WPL completed construction of the Grant County solar facility (200 MW in Grant County, Wisconsin).

• In May 2024, WPL announced updated plans to convert the coal-fired Edgewater Unit 5 to natural gas in 2028, subject to regulatory approvals. WPL previously planned to retire the EGU by June 1, 2025.

• In July 2024, the U.S. Department of Energy Office of Clean Energy Demonstrations awarded WPL’s Columbia Energy Storage Project, a 20 MW carbon dioxide-based long-duration energy storage system at the Columbia Energy Center (currently expected to be retired by June 1, 2026) site, up to approximately $30 million in grant funding during construction of the project. WPL currently expects to submit project plans to the PSCW later in 2024.

• In July 2024, WPL filed a certificate of authority application with the PSCW for approval to repower the Bent Tree wind farm, which would be eligible for production tax credits under the Inflation Reduction Act of 2022. A decision from the PSCW is currently expected in 2025.

Rate Matters:

• In October 2023, IPL filed a retail electric and gas rate review with the IUC for the October 2024 through September 2025 forward-looking Test Period. In June 2024, IPL reached a partial, non-unanimous settlement agreement with certain stakeholders, which is subject to IUC approval. Final rates are expected to be effective October 1, 2024. The settlement agreement reflects the following:

• Annual retail electric base rate increase of $185 million, with customers receiving credits for the first 12 months through a tax benefit rider, a subsequent retail electric base rate moratorium through September 2029, and an average retail electric rate base of $7,279 million;

• Annual retail gas base rate increase of $10 million, and an average retail gas rate base of $630 million;

• Return on common equity of 9.65% (for all assets that to do not have advance ratemaking principles) and a 51% common equity component of its regulatory capital structure;

• Key drivers include revenue requirement impacts of increasing electric and gas rate base, including investments in solar generation, as well as updated depreciation rates and certain incremental costs and benefits incurred resulting from the 2020 derecho windstorm;

• Earnings sharing mechanism beginning in 2025, where IPL would apply excess earnings to the remaining net book value of IPL’s highest earning asset with advance ratemaking principles (currently the Emery Generation Station) based on its authorized return on common equity as follows;

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Threshold Above Authorized
Return on Common Equity						Sharing
First 50 basis points						75% customers, 25% IPL
>50 to 100 basis points						50% customers, 50% IPL
>100 to 150 basis points						25% customers, 75% IPL
>150 basis points						100% customers

• Creation of an individual customer rate tariff, which would allow IPL to attract new load growth to its service territory;

• Electric distribution system investment cap not to exceed $900 million in aggregate or $325 million in any given year from 2026 through 2029, with certain exceptions;

• IPL to retain renewable tax benefits and energy margins for new generation resources, as well as retain renewable tax benefits from the repowering of existing wind farms, including the Franklin County wind farm;

• Discontinuation of the renewable energy rider; and

• A return of the remaining net book value of the Lansing Generating Station; however, the agreement does not include a return on the remaining net book value of Lansing, resulting in Alliant Energy and IPL recording a pre-tax non-cash charge of $60 million to “Asset valuation charge for IPL’s Lansing Generating Station” in their income statements in the second quarter of 2024.

• In July 2024, the PSCW issued an oral decision authorizing WPL to refund $34 million, plus interest, to its retail electric customers in the fourth quarter of 2024 for fuel-related costs incurred by WPL in 2023 that were lower than fuel-related costs used to determine rates for such period.

• Refer to Note 3 for discussion of WPL’s March 2024 filing for judicial review of PSCW orders related to the recovery and deferral of the return on incremental solar generation construction costs in 2024 and 2025.

Growing Customer Demand:

• Alliant Energy, IPL and WPL are pursuing opportunities for customer growth, including new customers at Alliant Energy’s development-ready sites in Iowa and Wisconsin, and have executed various agreements for data centers. The timing and amount of increases in load are subject to various factors, including interconnections, and any executed or future agreements with customers are not expected to result in immediate increases in load.

Environmental Matters:

• In May 2024, the EPA enacted the revised CCR Rule, which significantly expands the scope of regulation to include coal ash ponds at sites that no longer produce electricity and inactive landfills, including some IPL and WPL facilities. As a result, as discussed in Note 11, Alliant Energy, IPL and WPL recorded additional AROs in the second quarter of 2024. Alliant Energy, IPL and WPL continue to evaluate the revised CCR Rule and are unable to predict with certainty the future outcome or impact of these updates, including resolution of ongoing litigation.

• In May 2024, the EPA enacted the final Section 111(d) rule for certain fossil-fueled EGUs and repealed the Affordable Clean Energy rule. The final Section 111(d) rule requires states to implement plans to reduce carbon dioxide emissions through various Best System of Emission Reduction measures at affected sources, including retirement, enforceable limits on operational capacity, co-firing with low-greenhouse gases fuels, or carbon capture and storage technology. State plans are subject to EPA approval, and must be submitted by May 2026. The final rule’s compliance requirements will be phased in beginning in 2030 and covers fossil-fueled EGUs that utilize steam boilers to generate electricity, including IPL’s coal-fired Ottumwa Generating Station, George Neal Generating Station, Prairie Creek Generating Station Unit 3 and Louisa Generating Station, WPL’s coal-fired Edgewater Generating Station Unit 5 (WPL announced updated plans to convert the coal-fired Edgewater Unit 5 to natural gas in 2028, subject to regulatory approvals), and IPL’s natural gas-fired Burlington Generating Station and Prairie Creek Generating Station Unit 4. The final rule does not apply to EGUs that are retired by January 2032 and is not currently expected to impact WPL’s coal-fired Columbia Energy Center given current plans to retire this EGU prior to this deadline. In addition, the final rule does not impact existing natural gas-fired combustion turbines, including IPL’s Marshalltown Generating Station and Emery Generating Station, and WPL’s Riverside Energy Center and West Riverside Energy Center; however, these EGUs could be subject to future Section 111(d) rules to reduce carbon dioxide emissions from existing combustion turbines. Alliant Energy, IPL and WPL are currently unable to predict with certainty the future outcome or impact of these matters, including resolution of ongoing litigation.

• In May 2024, the EPA enacted final revised standards under Section 111(b), which establishes carbon dioxide emissions limits from certain new and reconstructed fossil-fueled EGU combustion turbines that commenced operation after May 23, 2023 with a capacity greater than 25 MW. The final revised standards do not apply to IPL’s Marshalltown Generating Station or WPL’s West Riverside Energy Center, which commenced operation prior to the applicability date of the final revised standards. Alliant Energy, IPL and WPL are currently unable to predict with certainty the future outcome or impact of these revised standards, including resolution of ongoing litigation.

• In May 2024, the EPA enacted a final rule that revises discharge limits for specific categories of wastewater from existing coal-fired EGUs. The new limitations will be implemented in each facility’s wastewater discharge permits issued by state agencies and become effective as soon as possible but no later than December 31, 2029. Alliant Energy, IPL and WPL are currently evaluating the final rule and are unable to predict with certainty future compliance impacts, including resolution of ongoing litigation; however, costs to comply with this rule could have a material impact on their financial condition and results of operations.

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Legislative Matters:

• In May 2024, the Major Economic Growth Attraction program was enacted in Iowa, which offers various tax incentives for up to two qualified businesses for certain large-scale projects with capital investments greater than $1 billion constructed on certified sites greater than 250 acres in Iowa. The most significant provision of this program for Alliant Energy encourages economic development in IPL’s service territory. Alliant Energy has various development-ready sites throughout Iowa, including the 1,300-acre Big Cedar Industrial Center Mega-site in Cedar Rapids, Iowa, and the 465-acre Prairie View Industrial Center Super Park in Ames, Iowa.

• In May 2024, legislation was enacted in Iowa related to the advance rate-making principles for certain investments in Iowa. The most significant provisions of this legislation for Alliant Energy would allow IPL to include electric storage and nuclear-fired generation projects in the advance rate-making principles request process prior to making these investments in Iowa, and require IPL to obtain a certificate of public convenience, use and necessity (GCU Certificate) from the IUC in order to construct electric storage projects.

RESULTS OF OPERATIONS

Financial Results Overview - 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. 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):

			2024												2023
			Income (Loss)						EPS						Income (Loss)						EPS
Utilities and Corporate Services			$85						$0.33						$164						$0.65
ATC Holdings			9						0.04						8						0.03
Non-utility and Parent			(7)						(0.03)						(12)						(0.04)
Alliant Energy Consolidated			$87						$0.34						$160						$0.64

Alliant Energy’s Utilities and Corporate Services net income decreased by $79 million for the three-month period, primarily due to an asset valuation charge for IPL’s Lansing Generating Station as a result of the proposed rate review settlement, an ARO charge allocated to the steam business at IPL due to the revised CCR Rule, the timing of income taxes, higher financing and depreciation expenses, estimated temperature impacts on retail electric and gas sales, and changes in WPL electric fuel-related costs, net of recoveries. These items were partially offset by higher revenue requirements from WPL’s capital investments.

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Net Income Variances - The following items contributed to increased (decreased) net income for the three and six months ended June 30, 2024 compared to the same periods in 2023 (in millions):

			Three Months																		Six Months
			Alliant Energy						IPL						WPL						Alliant Energy						IPL						WPL
Revenues:
Changes in electric utility (Refer to details below)			($10)						($27)						$17						$13						($24)						$37
Changes in gas utility (Refer to details below)			(8)						(4)						(4)						(80)						(46)						(34)
Changes in other utility			(3)						(3)						—						(1)						(1)						—
Changes in non-utility			3						—						—						3						—						—
Changes in total revenues			(18)						(34)						13						(65)						(71)						3
Operating expenses:
Changes in electric production fuel and purchased power (Refer to details below)			28						18						9						21						(3)						23
Changes in electric transmission service (Refer to details below)			(9)						(3)						(7)						(16)						(1)						(15)
Changes in cost of gas sold (Refer to details below)			8						3						5						76						39						37
Asset valuation charge for IPL’s Lansing Generating Station in 2024 (Refer to Note 2 for details)			(60)						(60)						—						(60)						(60)						—
Changes in other operation and maintenance (Refer to details below)			(14)						(17)						—						2						(6)						5
Changes in depreciation and amortization (Higher primarily due to WPL’s solar generation placed in service in 2023, as well as WPL’s amortization of liquidated damages related to West Riverside procurement contracts, which resulted in reductions to depreciation and amortization expenses in the first and second quarters of 2023)			(21)						(1)						(18)						(43)						(2)						(41)
Changes in taxes other than income taxes			(1)						—						(1)						(2)						(1)						(1)
Changes in total operating expenses			(69)						(60)						(12)						(22)						(34)						8
Changes in operating income			(87)						(94)						1						(87)						(105)						11
Other income and deductions:
Changes in interest expense (Higher primarily due to financings completed in 2024 and 2023)			(12)						(5)						(5)						(25)						(10)						(10)
Changes in equity income from unconsolidated investments, net (Refer to Note 5 for details)			1						—						—						—						—						—
Changes in allowance for funds used during construction (Primarily due to changes in levels of construction work in progress balances related to solar generation and battery storage)			(5)						7						(11)						(5)						13						(18)
Changes in Other			(3)						1						(4)						(2)						3						(5)
Changes in total other income and deductions			(19)						3						(20)						(32)						6						(33)
Changes in income before income taxes			(106)						(91)						(19)						(119)						(99)						(22)
Changes in income taxes (Refer to Note 9 for details)			33						20						11						41						19						18
Changes in net income			($73)						($71)						($8)						($78)						($80)						($4)

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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
			2024						2023						2024						2023						2024						2023						2024						2023
Three Months
Retail			$719						$730						5,948						5,982						$59						$67						5,730						6,303
Sales for resale:
Wholesale			43						49						653						678						N/A						N/A						N/A						N/A
Bulk power and other			13						13						1,087						1,104						N/A						N/A						N/A						N/A
Transportation/Other			14						7						14						14						10						10						29,102						25,778
			$789						$799						7,702						7,778						$69						$77						34,832						32,081
Six Months
Retail			$1,425						$1,414						11,937						12,182						$251						$329						25,848						28,614
Sales for resale:
Wholesale			89						95						1,333						1,376						N/A						N/A						N/A						N/A
Bulk power and other			34						37						2,757						2,347						N/A						N/A						N/A						N/A
Transportation/Other			32						21						29						29						22						24						63,009						58,392
			$1,580						$1,567						16,056						15,934						$273						$353						88,857						87,006

IPL			Electric																								Gas
			Revenues												MWhs Sold												Revenues												Dths Sold
			2024						2023						2024						2023						2024						2023						2024						2023
Three Months
Retail			$387						$410						3,291						3,320						$34						$38						2,679						2,946
Sales for resale:
Wholesale			13						14						173						178						N/A						N/A						N/A						N/A
Bulk power and other			(2)						1						205						360						N/A						N/A						N/A						N/A
Transportation/Other			6						6						8						8						6						6						9,590						9,555
			$404						$431						3,677						3,866						$40						$44						12,269						12,501
Six Months
Retail			$762						$771						6,656						6,863						$135						$179						12,885						14,406
Sales for resale:
Wholesale			26						26						356						365						N/A						N/A						N/A						N/A
Bulk power and other			(5)						9						529						856						N/A						N/A						N/A						N/A
Transportation/Other			12						13						16						16						13						15						21,284						21,589
			$795						$819						7,557						8,100						$148						$194						34,169						35,995

WPL			Electric																								Gas
			Revenues												MWhs Sold												Revenues												Dths Sold
			2024						2023						2024						2023						2024						2023						2024						2023
Three Months
Retail			$332						$320						2,657						2,662						$25						$29						3,051						3,357
Sales for resale:
Wholesale			30						35						480						500						N/A						N/A						N/A						N/A
Bulk power and other			15						12						882						744						N/A						N/A						N/A						N/A
Transportation/Other			8						1						6						6						4						4						19,512						16,223
			$385						$368						4,025						3,912						$29						$33						22,563						19,580
Six Months
Retail			$663						$643						5,281						5,319						$116						$150						12,963						14,208
Sales for resale:
Wholesale			63						69						977						1,011						N/A						N/A						N/A						N/A
Bulk power and other			39						28						2,228						1,491						N/A						N/A						N/A						N/A
Transportation/Other			20						8						13						13						9						9						41,725						36,803
			$785						$748						8,499						7,834						$125						$159						54,688						51,011

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Sales Trends and Temperatures - Alliant Energy’s retail electric sales volumes decreased 1% and 2% for the three and six months ended June 30, 2024, respectively, compared to the same periods in 2023, primarily due to changes in sales volumes to IPL’s industrial customers due to standby service customers that can use other generation and changes in temperatures. Alliant Energy’s retail gas sales volumes decreased 9% and 10% for the three and six months ended June 30, 2024, respectively, compared to the same periods in 2023, primarily due to changes in temperatures. The six-month decrease in sales was partially offset by an extra day of sales during the first quarter of 2024 due to leap year.

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

			Electric																																				Gas
			Three Months																		Six Months																		Three Months																		Six Months
			2024						2023						Change						2024						2023						Change						2024						2023						Change						2024						2023						Change
IPL			$1						$—						$1						($8)						($4)						($4)						($1)						($1)						$—						($7)						($4)						($3)
WPL			(2)						—						(2)						(12)						(5)						(7)						(2)						(1)						(1)						(7)						(3)						(4)
Total Alliant Energy			($1)						$—						($1)						($20)						($9)						($11)						($3)						($2)						($1)						($14)						($7)						($7)

Electric Sales for Resale - Bulk Power and Other - Bulk power and other volume changes were due to changes in sales in the wholesale energy markets operated by MISO. These changes are impacted by several factors, including the availability and dispatch of Alliant Energy’s EGUs and electricity demand within these wholesale energy markets. Changes in bulk power and other revenues were largely offset by changes in fuel-related costs, and therefore did not have a significant impact on operating income.

Gas Transportation/Other - Gas transportation/other sales volume changes were largely due to changes in the gas volumes supplied to Alliant Energy’s natural gas-fired EGUs caused by the availability and dispatch of such EGUs.

Electric Utility Revenue Variances - The following items contributed to increased (decreased) electric utility revenues for the three and six months ended June 30, 2024 compared to the same periods in 2023 (in millions):

			Three Months																		Six Months
			Alliant Energy						IPL						WPL						Alliant Energy						IPL						WPL
Higher revenue requirements at WPL (a)			$36						$—						$36						$74						$—						$74
Higher (lower) revenues due to changes in retail electric fuel-related costs (Refer to Electric Production Fuel and Purchased Power Expenses Variances below) (a)			(34)						(15)						(19)						(35)						11						(46)
Estimated changes in sales volumes caused by temperatures			(1)						1						(2)						(11)						(4)						(7)
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)			(4)						(4)						—						(9)						(9)						—
Lower revenues at IPL related to changes in the renewable energy rider (mostly offset by changes in income taxes)			(5)						(5)						—						(7)						(7)						—
Changes in WPL electric fuel-related costs, net of recoveries (b)			(7)						—						(7)						(7)						—						(7)
Higher (lower) sales for resale bulk power and other revenues			—						(3)						3						(3)						(14)						11
Other			5						(1)						6						11						(1)						12
			($10)						($27)						$17						$13						($24)						$37

(a)In December 2023, the PSCW issued an order authorizing an annual base rate increase of $49 million for WPL’s retail electric customers, covering the 2024 forward-looking Test Period, which reflects revenue requirement impacts of increasing electric rate base and lower forecasted fuel-related expenses.

(b)WPL’s cost recovery mechanism for retail fuel-related expenses supports deferrals of amounts that fall outside an

approved fuel monitoring range of forecasted fuel-related expenses determined by the PSCW each year. The difference

between revenue collected and actual fuel-related expenses incurred within the fuel monitoring range increases or

decreases Alliant Energy’s and WPL’s electric utility revenues. WPL estimates the increase (decrease) to electric utility

revenues from amounts within the fuel monitoring range were approximately ($5) million and ($4) million for the three and six months ended June 30, 2024, respectively, compared to $2 million and $3 million for the three and six months ended June 30, 2023, respectively.

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Gas Utility Revenue Variances - The following items contributed to increased (decreased) gas utility revenues for the three and six months ended June 30, 2024 compared to the same periods in 2023 (in millions):

			Three Months																		Six Months
			Alliant Energy						IPL						WPL						Alliant Energy						IPL						WPL
Lower revenues due to changes in gas costs (Refer to Cost of Gas Sold Expense Variances below)			($8)						($3)						($5)						($75)						($38)						($37)
Estimated changes in sales volumes caused by temperatures			(1)						—						(1)						(7)						(3)						(4)
Higher revenue requirements at WPL (a)			1						—						1						6						—						6
Other			—						(1)						1						(4)						(5)						1
			($8)						($4)						($4)						($80)						($46)						($34)

(a)In December 2023, the PSCW issued an order authorizing an annual base rate increase of $13 million for WPL’s retail gas customers, covering the 2024 forward-looking Test Period, which reflects revenue requirement impacts of increasing gas rate base.

Electric Production Fuel and Purchased Power Expenses Variances - The following items contributed to (increased) decreased electric production fuel and purchased power expenses for the three and six months ended June 30, 2024 compared to the same periods in 2023 (in millions):

			Three Months																		Six Months
			Alliant Energy						IPL						WPL						Alliant Energy						IPL						WPL
Lower electric production fuel costs (a)			$23						$20						$3						$78						$58						$20
Changes in regulatory recovery of retail electric fuel-related costs			34						16						18						2						(23)						25
Higher purchased power expense (b)			(28)						(18)						(10)						(55)						(38)						(17)
Other			(1)						—						(2)						(4)						—						(5)
			$28						$18						$9						$21						($3)						$23

(a)Electric production fuel costs decreased for the three and six months ended June 30, 2024, compared to the same periods in 2023, primarily due to lower natural gas prices at IPL and WPL, and lower natural gas and coal volumes at IPL due to lower dispatch of IPL’s EGUs in 2024. The six-month decrease was partially offset by higher coal volumes at WPL due to higher dispatch of WPL’s coal-fired EGUs in 2024.

(b)Purchased power expense increased for the three and six months ended June 30, 2024, compared to the same periods in 2023, primarily due to higher prices for electricity purchased by IPL and WPL.

Electric Transmission Service Expense Variances - The following items contributed to (increased) decreased electric transmission service expense for the three and six months ended June 30, 2024 compared to the same periods in 2023 (in millions):

			Three Months																		Six Months
			Alliant Energy						IPL						WPL						Alliant Energy						IPL						WPL
Changes in regulatory recovery for the difference between actual electric transmission service costs and those costs used to determine rates			($7)						($3)						($4)						($11)						($2)						($9)
Other			(2)						—						(3)						(5)						1						(6)
			($9)						($3)						($7)						($16)						($1)						($15)

Cost of Gas Sold Expense Variances - The following items contributed to (increased) decreased cost of gas sold expense for the three and six months ended June 30, 2024 compared to the same periods in 2023 (in millions):

			Three Months																		Six Months
			Alliant Energy						IPL						WPL						Alliant Energy						IPL						WPL
Lower natural gas prices and lower retail gas volumes primarily due to changes in temperatures			$10						$5						$5						$84						$55						$29
Changes in the regulatory recovery of gas costs			(1)						(1)						—						(8)						(16)						8
Other			(1)						(1)						—						—						—						—
			$8						$3						$5						$76						$39						$37

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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, 2024 compared to the same periods in 2023 (in millions):

			Three Months																		Six Months
			Alliant Energy						IPL						WPL						Alliant Energy						IPL						WPL
Lower energy efficiency expense at IPL (mostly offset by lower revenues)			$5						$5						$—						$12						$12						$—
ARO charge for steam assets at IPL			(20)						(20)						—						(20)						(20)						—
Other			1						(2)						—						10						2						5
			($14)						($17)						$—						$2						($6)						$5

LIQUIDITY AND CAPITAL RESOURCES

The liquidity and capital resources summary included in the 2023 Form 10-K has not changed materially, except as described below.

Liquidity Position - At June 30, 2024, Alliant Energy had $92 million of cash and cash equivalents, $948 million ($398 million at the parent company, $250 million at IPL and $300 million at WPL) of available capacity under the single revolving credit facility and $65 million of available capacity at IPL under its sales of accounts receivable program.

Capital Structure - Capital structures at June 30, 2024 were as follows (Long-term Debt (including current maturities) (LD); Common Equity (CE)):

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

			Alliant Energy												IPL												WPL
			2024						2023						2024						2023						2024						2023
Cash, cash equivalents and restricted cash, January 1			$63						$24						$53						$15						$7						$5
Cash flows from (used for):
Operating activities			562						311						147						52						391						268
Investing activities			(533)						(482)						(209)						(15)						(247)						(402)
Financing activities			1						161						18						(43)						(71)						132
Net increase (decrease)			30						(10)						(44)						(6)						73						(2)
Cash, cash equivalents and restricted cash, June 30			$93						$14						$9						$9						$80						$3

Operating Activities - The following items contributed to increased (decreased) operating activity cash flows for the six months ended June 30, 2024 compared to the same period in 2023 (in millions):

			Alliant Energy						IPL						WPL
Changes in income taxes paid/received (a)			$86						$67						$32
Higher collections from WPL’s retail electric and gas base rate increases			80						—						80
Timing of WPL’s fuel-related cost recoveries from retail electric customers			18						—						18
Lower contributions to qualified defined benefit pension plans			10						—						10
Timing of intercompany payments and receipts			—						(10)						(26)
Changes in gas stored underground			(36)						(16)						(20)
Changes in interest payments			(28)						(11)						(7)
Decreased collections from IPL’s and WPL’s retail customers caused by temperature impacts on electric and gas sales			(18)						(7)						(11)
Other (primarily due to other changes in working capital)			139						72						47
			$251						$95						$123

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(a)Refer to the cash flows statements for details of renewable tax credits transferred to other corporate taxpayers during the six months ended June 30, 2024.

Investing Activities - The following items contributed to increased (decreased) investing activity cash flows for the six months ended June 30, 2024 compared to the same period in 2023 (in millions):

			Alliant Energy						IPL						WPL
(Higher) lower utility construction and acquisition expenditures (a)			($112)						($249)						$137
Changes in the amount of cash receipts on sold receivables			34						34						—
Other			27						21						18
			($51)						($194)						$155

(a)Largely due to higher expenditures for WPL’s battery storage and IPL’s solar generation, partially offset by lower expenditures for WPL’s solar generation.

Construction and Acquisition Expenditures - Alliant Energy and IPL are currently evaluating potential impacts from an electric distribution system investment cap included in IPL’s rate review settlement agreement, which is subject to IUC approval and could impact future construction and acquisition expenditures. Refer to “2024 Highlights” for additional information on IPL’s rate review settlement agreement.

Financing Activities - The following items contributed to increased (decreased) financing activity cash flows for the six months ended June 30, 2024 compared to the same period in 2023 (in millions):

			Alliant Energy						IPL						WPL
Net changes in the amount of commercial paper and other short-term borrowings outstanding			($277)						($55)						($72)
Lower net proceeds from common stock issuances			(64)						—						—
(Higher) lower common stock dividends			(20)						40						(6)
Higher (lower) capital contributions from IPL’s and WPL’s parent company, Alliant Energy			—						85						(125)
Lower payments to retire long-term debt			99						—						—
Higher net proceeds from issuance of long-term debt			107						—						—
Other			(5)						(9)						—
			($160)						$61						($203)

Common Stock Issuances - Refer to Note 6 for discussion of common stock issuances by Alliant Energy in 2024.

Long-term Debt - Refer to Note 7(b) for discussion of various issuances and/or retirements of long-term debt by AEF and WPL in 2024.

Impact of Credit Ratings on Liquidity and Collateral Obligations -

Ratings Triggers - In March 2024, Standard & Poor’s Ratings Services changed Alliant Energy’s and IPL’s outlooks from stable to negative. These outlook changes are not expected to have a material impact on Alliant Energy’s and IPL’s liquidity or collateral obligations.

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 2023 Form 10-K and has not changed materially from the items reported in the 2023 Form 10-K, except for the items described in Notes 4, 7 and 14.

OTHER MATTERS

Critical Accounting Estimates - The summary of critical accounting estimates included in the 2023 Form 10-K has not changed materially, except as described below.

Regulatory Assets and Regulatory Liabilities - In May 2023, IPL retired the Lansing Generating Station. IPL is currently allowed a full recovery of and a full return on this EGU from both its retail and wholesale customers. IPL’s retail electric rate review for the October 2024 through September 2025 forward-looking Test Period filed with the IUC in October 2023 included a request for continued recovery of and a return on the remaining net book value of Lansing through 2037. IPL’s partial non-unanimous rate review settlement agreement filed with the IUC in June 2024 includes a return of the remaining net book value of Lansing; however, the agreement does not include a return on the remaining net book value of Lansing, therefore the return on the remaining net book value is no longer probable of recovery from IPL’s retail electric customers. As a result, in the second quarter of 2024, a pre-tax non-cash charge of $60 million was recorded to “Asset valuation charge for IPL’s Lansing Generating Station” in Alliant Energy’s and IPL’s income statements, with a corresponding decrease in Alliant Energy’s and

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IPL’s assets retired early regulatory assets. A decision from the IUC on the settlement agreement is currently expected in the third quarter of 2024.

Long-Lived Assets -

Regulated Operations -

Generating Units Subject to Early Retirement - In May 2024, WPL announced updated plans to convert the coal-fired Edgewater Unit 5 to natural gas in 2028, subject to regulatory approvals. WPL previously planned to retire the EGU by June 1, 2025. As a result, Alliant Energy and WPL concluded Edgewater Unit 5 no longer meets the criteria to be considered probable of abandonment as of June 30, 2024. Refer to Note 3 for further discussion of Edgewater Unit 5.

Solar Generation Projects Recently Completed or Under Construction - Alliant Energy and WPL currently expect construction costs associated with WPL’s approximately 1,100 MW of new solar generation will exceed the construction cost estimates previously approved by the PSCW by approximately $195 million. In February 2024, the PSCW issued an order approving deferral of the incremental solar generation construction costs. The PSCW’s order did not authorize a deferral for the return on such costs. In March 2024, WPL filed for judicial review of the PSCW’s retail electric rate review order (2024/2025 forward-looking Test Period) and solar generation construction cost deferral order related to the recovery and deferral of the return on the incremental solar generation construction costs in 2024 and 2025. Alliant Energy and WPL concluded that there was not a probable disallowance of anticipated higher rate base amounts as of June 30, 2024 given construction costs were reasonably and prudently incurred.

AROs - The fair value of a legal obligation associated with the retirement of an asset is recorded as a liability when an asset is placed in service, when a legal obligation is subsequently identified or when sufficient information becomes available to determine a reasonable estimate of the fair value of future retirement costs. Alliant Energy, IPL and WPL estimate the fair value of their AROs using present value techniques, in which they make various assumptions, including estimates of the amounts and timing of future cash flows associated with retirement activities, inflation and discount rates. Estimates of the timing and amounts of future cash outlays are based on projections of when and how assets will be retired and the cost of future removal activities. The estimates are subject to change and future updates could have a material impact on Alliant Energy’s, IPL’s and WPL’s financial condition and results of operations. In the second quarter of 2024, substantially due to the enactment of the revised CCR Rule, which significantly expands the scope of regulation to include coal ash ponds at sites that no longer produce electricity and inactive landfills, Alliant Energy, IPL and WPL recorded additional AROs of $355 million, $102 million and $253 million, respectively. These amounts are expected to be adjusted in the future as additional information is obtained for the specific site closure plans, including the determination of whether or not individual sites are considered legal obligations and the acceptance and approval of compliance approaches, which could change management assumptions and result in a material change to the recorded ARO amounts. Refer to Note 11 for further discussion of AROs.