What changed in this filing

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Item 7. Management’s Discussion and Analysis

2023-02-24 compared with 2022-02-18 · 232 added, 211 removed, 373 unchanged (54% of the section changed)

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Refer to MDA in the combined 2021 Form 10-K for details on certain financial information for 2021 compared to 2020.

Strategy and Mission

Alliant Energy’s mission is to deliver affordable energy solutions and exceptional service that its customers and communities count on - safely, efficiently, reliably and responsibly.

The mission is supported by a strategy focused on meeting the evolving expectations of customers while providing an attractive return for investors, as well as serving its customers and building strong communities.

Table of Co ntents

Mission, Purpose and Strategy

Alliant Energy’s mission is to deliver affordable energy solutions and exceptional service that its customers and communities count on - affordably, safely, reliably, and sustainably.

This mission aligns with Alliant Energy’s purpose - to serve customers and build stronger communities - which guides it through the ever-changing dynamics of the economy and the energy industry.

Alliant Energy takes its responsibility as a corporate citizen seriously and remains a careful steward of the environment and supports the communities in its service territories.

Alliant Energy’s mission and purpose is supported by a strategy focused on meeting the evolving expectations of customers while providing an attractive return for investors, and pursuing emerging technologies and safe, sustainable methods of energy production.

This strategy includes the following key elements:

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Key Highlights -

• Alliant Energy’s Clean Energy Blueprints, also known as its cleaner energy strategy, is expected to result in cost savings for its utility customers through the planned transition away from coal-fired EGUs and incorporation of additional renewable energy, renewable tax credits for investments in renewable energy projects, and utilization of renewable project tax equity financing under the current tax regulations.

• WPL maintaining flat base rates in 2021 by utilizing Federal Tax Reform benefits and expected lower fuel costs to offset higher revenue requirements from rate base additions.

• IPL’s renewable energy rider became effective February 26, 2020, which allows for annual adjustments to electric rates charged to IPL’s retail electric customers for actual renewable energy costs incurred to fund IPL’s 1,000 MW of wind EGUs placed in service in 2019 and 2020, and related tax benefits, including production tax credits.

• Alliant Energy’s Clean Energy Blueprint, also known as its cleaner energy strategy, continues to add clean energy resources in Iowa and Wisconsin, which directly reinvests in the communities Alliant Energy serves through the addition of skilled jobs, economic development and increased tax revenue.

The execution of Alliant Energy’s strategy is expected to result in cost benefits for its utility customers by continuing to add renewable energy projects that generate fuel cost benefits and renewable tax credits that are provided to its electric customers.

Alliant Energy, IPL and WPL currently expect to utilize various provisions of the Inflation Reduction Act of 2022 to enhance the tax benefits expected from their announced solar and battery storage projects, including transferring certain future tax credits from such projects to other corporate taxpayers.

• In 2022, Alliant Energy’s wind generation was the highest in its history, which resulted in renewable tax credits and fuel cost savings for its customers.

• Reductions in Iowa corporate income tax rates resulting from tax reform enacted in March 2022 are expected to provide cost benefits to IPL’s customers in the future.

• IPL maintaining flat base rates for its retail electric and gas customers in 2021 and 2022.

• Providing $35 million of billing credits to IPL’s retail electric customers beginning in the third quarter of 2020 through June 2021, largely driven by Federal Tax Reform benefits for customers.

• Significant fuel cost reductions achieved in 2021 as a result of expansion of renewable generation and shortening the term of IPL’s DAEC PPA by 5 years.

• Issuance of new long-term debt in 2021 at historically low interest rates for IPL ($300 million of 3.1% senior debentures due 2051) and WPL ($300 million of 1.95% green bonds due 2031).

• Significant fuel cost reductions achieved in 2021 and 2022 as a result of shortening the term of IPL’s DAEC PPA by 5 years.

• Issuance of new long-term debt at historically low interest rates for IPL ($300 million of 3.1% senior debentures due 2051) and WPL ($300 million of 1.95% green bonds due 2031) in 2021, and WPL ($600 million of 3.95% green bonds due 2032) in 2022.

• Redemption of IPL’s 5.1% cumulative preferred stock in 2021.

• Levelized cost recovery mechanism for the remaining net book value of Edgewater Unit 5, which helps reduce customer costs in 2022 and 2023.

Making customer-focused investments - Alliant Energy’s strategic priorities include making significant customer-focused investments toward cleaner energy and sustainable customer solutions.

Making customer-focused investments - Alliant Energy’s strategic priorities include making significant customer-focused investments toward cleaner energy and resilient and sustainable customer solutions.

Alliant Energy’s strategy drives a capital allocation process focused on:

1) transitioning its generation portfolio to meet the growing interest of customers for cleaner sources of energy, 2) upgrading its electric and gas distribution systems to strengthen safety and resiliency, as well as enable distributed energy solutions in its service territories, and 3) enhancing its customers’ experience with evolving technology and greater flexibility.

1) transitioning its generation portfolio to meet the growing interest of customers for reliable and sustainable sources of energy, 2) upgrading its electric and gas distribution systems to strengthen safety and resiliency, as well as enable distributed energy solutions in its service territories, and 3) enhancing its customers’ and employees’ experience with evolving technology and greater flexibility.

Key Highlights (refer to “ Customer Investments ” for details) -

• Planned development and acquisition of additional renewable energy, including approximately 1,100 MW of solar generation at WPL with in-service dates in 2022 and 2023, approximately 400 MW of solar generation at IPL with in-service dates in 2023 and 2024 and approximately 75 MW of battery storage in 2024 at IPL.

• Planned development and acquisition of additional renewable energy, including approximately 1,100 MW of solar generation at WPL with in-service dates in 2022-2024, approximately 275 MW of battery storage at WPL with in-service dates in 2024 and 2025, approximately 400 MW of solar generation at IPL with in-service dates in 2023 and 2024, and approximately 75 MW of battery storage at IPL with in-service dates in 2024.

In addition, IPL and WPL continue to evaluate additional opportunities to add more renewable generation, including repowering of existing wind farms and additional solar generation and distributed energy resources, including community solar and energy storage systems.

• IPL’s December 2021 completion of the fuel switch of the Burlington Generating Station (212 MW) from coal to natural gas.

• Plans to construct and/or acquire additional renewable, battery and natural gas resources to meet the requirements of MISO’s new seasonal resource adequacy process establishing capacity planning reserve margin and capacity accreditation requirements effective with the 2023/2024 MISO Planning Year.

• WPL’s completion of new solar generation in Wisconsin in 2022, including 150 MW in Wood County, 50 MW in Richland County, and 50 MW in Rock County.

Table of Co ntents

Growing customer demand - Alliant Energy’s strategy supports expanding electric and gas usage in its service territories by promoting electrification initiatives and economic development in the communities it serves.

Key Highlights -

• WPL entered into a new wholesale power supply agreement, which was effective January 1, 2021 and brought approximately 55 MW of load to WPL’s electric system in 2021.

• Alliant’s Energy’s economic development efforts resulted in being named a Top Utility in Economic Development by Site Selection Magazine for the fourth year in a row, and in 2022 being awarded the Chairman’s Award for Workforce Development Leadership by the Center for Energy Workforce Development.

• Alliant Energy continues to partner with its commercial and industrial customers to help develop renewable solutions to enhance their sustainability initiatives, including planned solar facilities in Iowa and Wisconsin.

• Alliant Energy has various development-ready sites throughout Iowa and Wisconsin, including the 1,300-acre Big Cedar Industrial Center Mega-site in Cedar Rapids, Iowa, and the 730-acre Prairie View Industrial Center Super Park in Ames, Iowa, which are rail-served ready-to-build manufacturing and industrial sites in close proximity to the regional airport and interstate freeways and access IPL’s electric services.

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In addition, the Beaver Dam Commerce Park is a 520-acre ready-to-build manufacturing and industrial site in Beaver Dam, Wisconsin, with access to commercial and freight airports, interstate freeways and WPL’s electric services.

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;

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 any 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.

Alliant Energy’s construction projects are currently progressing as planned with added safety protocols, and while it continues to monitor its supply chain, Alliant Energy has experienced supply constraints and commodity inflation in the solar market.

Alliant Energy’s wind farms under construction during the pandemic were placed in service in 2020 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 “ Liquidity and Capital Resources ” 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 and supply chain impacts but does not 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, especially early on in the pandemic.

While the total expected impact of COVID-19 on future sales is currently unknown, Alliant Energy experienced higher electric residential sales and lower electric commercial and industrial sales in 2020, and lower electric residential sales and higher electric commercial and industrial sales in 2021.

In addition, Alliant Energy has not experienced a material increase in customer bankruptcies in 2020 or 2021.

Liquidity and Capital Resources Impacts - Alliant Energy maintains a single credit facility, which allows borrowing capacity to shift among Alliant Energy (at the parent company level), IPL and WPL, as needed.

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 has not experienced any material negative impacts related to customer arrears and bad debts as a result of the pandemic;

however, if government funds are no longer available for customers to help pay their utility bills, it may negatively impact Alliant Energy’s customers’ willingness and ability to pay, which could negatively impact Alliant Energy’s cash flows from operations.

Currently, Alliant Energy does not anticipate any material credit risk related to its commodity transactions.

Legislative Impacts - Refer to “ Le gislative Matters ” for discussion of legislation that was enacted in 2020 related to impacts from COVID-19.

RESULTS OF OPERATIONS

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Alliant Energy Consolidated $686 $2.73 $659 $2.63

Alliant Energy’s Utilities and Corporate Services income increased $46 million in 2021 compared to 2020.

The increase was primarily due to higher earnings resulting from IPL’s and WPL’s increasing rate base, as well as higher sales due in part to the derecho windstorm in Iowa and COVID-19 sales impacts in 2020.

These items were partially offset by higher depreciation expense and lower AFUDC.

Alliant Energy’s Utilities and Corporate Services net income increased by $58 million in 2022 compared to 2021.

The increase was primarily due to higher revenue requirements and AFUDC from WPL capital investments and higher electric and gas margins, including the impacts of temperatures.

These items were partially offset by higher depreciation expense.

Alliant Energy’s Non-utility and Parent net income decreased by $29 million in 2022 compared to 2021, primarily due to higher financing expense and the impact of the Iowa state income tax rate change.

Table of Co ntents

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):

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Alliant Energy IPL WPL

Total higher utility electric margin variance (Refer to details below) $83 $45 $38

Total higher (lower) utility electric margin variance (Refer to details below) $116 ($21) $137

Total higher utility gas margin variance (Refer to details below) 55 29 26

Total (higher) lower other operation and maintenance expenses variance (Refer to details below) (6) 13 (14)

Higher depreciation and amortization expense primarily due to additional plant in service in 2020 and 2021, including IPL’s new wind generation, and WPL’s West Riverside Energy Center and Kossuth wind farm

Total higher other operation and maintenance expenses variance (Refer to details below) (28) (7) (10)

Total higher depreciation and amortization expense

Other 4 (2) (2)

$133 ($7) $144

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Retail $3,019 $2,771 25,409 25,432 $588 $413 55,021 48,179

Sales for resale 243 204 5,805 6,046 N/A N/A N/A N/A

Sales for resale:

Wholesale 233 187 2,866 2,787 N/A N/A N/A N/A

Bulk power and other 111 56 3,734 3,018 N/A N/A N/A N/A

Transportation/Other 58 67 62 71 54 43 104,812 99,179

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Retail $1,747 $1,633 14,270 14,283 $317 $237 28,492 24,881

Sales for resale 74 88 1,807 3,485 N/A N/A N/A N/A

Sales for resale:

Wholesale 64 57 771 738 N/A N/A N/A N/A

Bulk power and other 13 17 1,401 1,069 N/A N/A N/A N/A

Transportation/Other 35 45 33 35 34 28 43,264 40,738

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Retail $1,272 $1,138 11,139 11,149 $271 $176 26,529 23,298

Sales for resale 169 116 3,998 2,561 N/A N/A N/A N/A

Sales for resale:

Wholesale 169 130 2,095 2,049 N/A N/A N/A N/A

Bulk power and other 98 39 2,333 1,949 N/A N/A N/A N/A

Transportation/Other 23 22 29 36 20 15 61,548 58,441

$1,562 $1,329 15,596 15,183 $291 $191 88,077 81,739

Sales Trends and Temperatures - Alliant Energy’s retail electric sales volumes increased 4% in 2021 compared to 2020, primarily due to changes in temperatures, COVID-19 impacts in Alliant Energy’s service territories and impacts from the derecho windstorm in IPL’s service territory in August 2020, partially offset by the impact on sales of the additional day due to leap year in 2020.

Alliant Energy’s retail gas sales volumes decreased 1% in 2021 compared to 2020, primarily due to changes in temperatures and the impact on sales of the additional day due to leap year in 2020, partially offset by COVID-19 impacts in Alliant Energy’s service territories.

In 2021, changes in COVID-19 impacts resulted in decreases for retail electric residential sales volumes and increases for retail electric commercial and industrial sales.

Table of Co ntents

Sales Trends and Temperatures - Alliant Energy’s retail electric sales volumes were unchanged in 2022 compared to 2021 primarily due to increases in sales volumes to residential and commercial customers caused by changes in temperatures, offset by decreases in sales volumes to industrial customers caused by maintenance outages and labor-related disruptions at certain large customers.

Alliant Energy’s retail gas sales volumes increased 14% in 2022 compared to 2021, primarily due to changes in temperatures and increases in the number of retail gas customers.

Estimated increases (decreases) to electric and gas margins from the impacts of temperatures were as follows (in millions):

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Alliant Energy IPL WPL

Higher revenue requirements due to increasing rate base (a) (b) $43 $29 $14

Higher revenue requirements at WPL due to increasing rate base (a) $121 $— $121

Higher revenues at IPL due to changes in credits on customers’ bills related to excess deferred income tax benefits amortization through the tax benefit rider (offset by changes in income taxes) 11 11 —

Estimated changes in sales volumes caused by temperatures 7 4 3

Higher wholesale margins at WPL partially due to a new wholesale customer in 2021 8 — 8

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) (14) (14) —

Other (includes higher temperature-normalized sales primarily due to the derecho windstorm in 2020 and COVID-19 impacts) 31 19 12

(a) IPL’s 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.

The final rate increase includes 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.

In September 2020, IPL made a buyout payment of $110 million in exchange for shortening the terms of its DAEC PPA by 5 years.

The higher revenue requirements from the buyout payment, including a return on such costs, is being recovered from IPL’s retail customers from 2021 through the end of 2025.

Refer to Note 2 for further discussion.

(b) In December 2020, the PSCW issued an order authorizing WPL to maintain its current retail electric base rates through the end of 2021.

WPL utilized anticipated fuel-related cost savings and excess deferred income tax benefits in 2021 to offset the revenue requirement impacts of increasing electric rate base, including the Kossuth wind farm, which was placed in service in October 2020.

The lower fuel expense benefits are recognized in electric margin and the additional amount of excess deferred income tax benefits is recognized as a reduction in income tax expense.

Lower revenues at IPL related to changes in the renewable energy rider (mostly offset by changes in income taxes caused by higher production tax credits) (37) (37) —

Other (includes higher wholesale margins at WPL) 14 1 13

$116 ($21) $137

(a) In December 2021, the PSCW issued an order authorizing annual base rate increases of $114 million and $15 million for WPL’s retail electric and gas customers, respectively, covering the 2022/2023 forward-looking Test Period, which was based on a stipulated agreement between WPL and certain stakeholders.

The key drivers for the annual base rate increases include higher retail fuel-related costs in 2022, lower excess deferred income tax benefits in 2022 and 2023 compared to 2021, and revenue requirement impacts of increasing electric and gas rate base, including investments in solar generation.

Retail electric rate changes were effective on January 1, 2022 and extend through the end of 2023.

Retail gas rate changes were effective on January 1, 2022 and extended through the end of 2022.

The higher fuel expense costs are recognized in electric margin and the lower amount of excess deferred income tax benefits is recognized as an increase in income tax expense.

Utility Gas Margin Variances - The following items contributed to increased (decreased) utility gas margins for 2022 compared to 2021 (in millions):

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Higher 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) $17 $17 $—

Higher revenue requirements at WPL due to increasing rate base (refer to (a) above) 17 — 17

Estimated changes in sales volumes caused by temperatures 10 6 4

Other (includes higher sales in 2022) 11 6 5

Table of Co ntents

Other Operation and Maintenance Expenses Variances - The following items contributed to (increased) decreased other operation and maintenance expenses for 2022 compared to 2021 (in millions):

Alliant Energy IPL WPL

Higher generation operation and maintenance expenses ($17) ($12) ($5)

Credit loss adjustments in 2020 related to guarantees for an affiliate of Whiting Petroleum (Refer to Note 17(d) )

Lower bad debt expense at IPL 13 13 —

Lower energy efficiency expense at IPL (primarily offset by changes in electric and gas revenues) 7 7 —

Higher energy efficiency expense at IPL (mostly offset by higher revenues) ($15) ($15) $—

Non-utility Travero (mostly offset by higher revenues) (9) — —

Other (4) 8 (10)

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Alliant Energy IPL WPL

Lower AFUDC primarily due to changes in CWIP balances related to IPL’s new wind generation, and WPL’s West Riverside Energy Center and Kossuth wind farm, placed in service in 2020 ($30) ($15) ($15)

Higher interest expense primarily due to financings completed in 2022 and 2021, and higher interest rates ($48) ($9) ($16)

Lower equity income from unconsolidated investments, net (refer to Not e 6 for details of a reduction recorded in 2022 related to the MISO return on equity complaint)

Higher AFUDC primarily due to changes in CWIP balances related to WPL’s solar generation 35 2 33

Other (refer to Note 13(a) for details of IPL’s qualified pension plan settlement losses)

($25) ($12) $20

Income Taxes - Refer to Note 12 for details of effective income tax rates.

Preferred Dividend Requirements of IPL - Refer to Note 8 for details of the redemption of IPL’s 5.1% cumulative preferred stock in December 2021, including a $5 million non-cash charge recorded in 2021 related to this transaction.

Income Taxes - Refer to Note 12 for details of effective income tax rates, including the impact of Iowa tax reform in 2022.

Preferred Dividend Requirements of IPL - Refer to Note 8 for details of the redemption of IPL’s 5.1% cumulative preferred stock in 2021, including a $5 million non-cash charge recorded in 2021 related to this transaction.

Other Future Considerations - In addition to items discussed in this report, the following key items could impact Alliant Energy’s, IPL’s and WPL’s future financial condition or results of operations:

• Financing Plans - WPL and AEF currently expect to issue up to $600 million and $800 million of long-term debt, respectively, in 2022.

WPL, AEF and Corporate Services have $250 million, $300 million and $75 million of long-term debt maturing in 2022, respectively.

Alliant Energy currently expects to issue approximately $25 million of common stock in 2022 through its Shareowner Direct Plan.

• Financing Plans - Alliant Energy currently expects to issue up to $250 million of common stock in 2023 through the distribution agreement for the sale from time to time of up to $225 million of common stock that was executed in December 2022, and its Shareowner Direct Plan.

Alliant Energy and its subsidiaries currently expect to issue up to $1.2 billion of long-term debt in 2023.

AEF has $400 million of long-term debt maturing in 2023.

• Common Stock Dividends - Alliant Energy announced a 6% increase in its targeted 2023 annual common stock dividend to $1.81 per share, which is equivalent to a quarterly rate of $0.4525 per share, beginning with the February 2023 dividend payment.

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• Higher Earnings on Increasing Rate Base - Alliant Energy and WPL currently expect an increase in earnings in 2023 compared to 2022 due to impacts from increasing revenue requirements related to investments in the utility business, including WPL’s solar investments.

WPL’s increased revenue requirements are expected to be offset by higher income tax expense as a result of lower tax benefits.

• Depreciation and Amortization Expenses - Alliant Energy, IPL and WPL currently expect an increase in depreciation and amortization expenses in 2022 compared to 2021 due to property additions, including WPL’s expansion of solar generation.

• Interest Expense - Alliant Energy, IPL and WPL currently expect an increase in interest expense in 2022 compared to 2021 due to financings completed in 2021 and planned in 2022 as discussed above.

• Allowance for Funds Used During Construction - Alliant Energy and WPL currently expect AFUDC to increase in 2022 compared to 2021 primarily due to increased CWIP balances related to WPL’s solar generation.

• Preferred Dividend Requirements of IPL - Alliant Energy and IPL currently expect a decrease in preferred dividend requirements in 2022 compared to 2021 due to the redemption of IPL’s 5.1% cumulative preferred stock in December 2021.

• Other Operation and Maintenance Expenses - Alliant Energy, IPL and WPL currently expect a decrease in other operation and maintenance expenses in 2023 compared to 2022 largely due to cost reductions resulting from operating efficiencies.

• Interest Expense - Alliant Energy, IPL and WPL currently expect an increase in interest expense in 2023 compared to 2022 due to financings completed in 2022 and planned in 2023 as discussed above, as well as expected higher interest rates.

CUSTOMER INVESTMENTS

Alliant Energy’s, IPL’s and WPL’s strategic priorities include making significant customer-focused investments toward cleaner energy and sustainable customer solutions.

Alliant Energy’s, IPL’s and WPL’s strategic priorities include making significant customer-focused investments toward cleaner energy and resilient and sustainable customer solutions.

These priorities include:

Environmental Stewardship

Alliant Energy’s environmental stewardship is focused on meeting its customers’ energy needs in an economical, efficient, reliable and sustainable manner.

Alliant Energy proactively considers future environmental compliance requirements and proposed regulations in its planning, decision-making, construction and ongoing operations activities.

Alliant Energy is focused on executing a long-term strategy to deliver reliable and affordable energy with lower emissions independent of changing policies and political landscape.

To achieve these long-term goals, Alliant Energy will transition away from coal-fired EGUs by

incorporating renewable energy, distributed energy resources, energy efficiency, demand response, highly-efficient natural gas-fired EGUs and other emerging technologies such as energy storage.

Alliant Energy’s voluntary environmental-related goals and achievements include the following:

• Exceeded its 2020 targets by reducing air emissions for sulfur dioxide by over 90%, nitrogen oxide by over 80% and mercury by over 90% from 2005 levels.

• By 2030, reduce CO2 emissions by 50% from its owned fossil-fueled EGUs and reduce electric utility water supply by 75% from 2005 levels, and transition 100% of its owned light-duty fleet vehicles to be electric, as well as partner to plant more than 1 million trees by the end of 2030.

• By 2040, eliminate all coal-fired EGUs from its generating fleet.

• By 2050, achieve an aspirational goal of net-zero CO2 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.

Renewable Generation

Alliant Energy has developed Clean Energy Blueprints, or its cleaner energy strategy, as a guide to meet customer demand for affordable, reliable and cleaner energy in Iowa and Wisconsin.

This strategy includes the planned development and acquisition of additional renewable energy, including approximately 1,100 MW of solar generation at WPL with in-service dates in 2022 and 2023, approximately 400 MW of solar generation at IPL with in-service dates in 2023 and 2024 and approximately 75 MW of battery storage in 2024 at IPL.

In addition, WPL’s plans include up to 300 MW of additional capacity.

Alliant Energy, IPL and WPL continue to evaluate additional opportunities to add more renewable generation, repowering of existing wind farms, and distributed energy resources, including community solar and energy storage systems.

Estimated capital expenditures for these planned projects for 2022 through 2025 are included in the “Renewable projects” line in the construction and acquisition table in “ Liquidity and Capital Resources .” These estimates include current expectations for higher costs for various projects, as supply constraints and commodity inflation continue to be prevalent in the solar market.

IPL and WPL currently assume that a portion of the construction costs for the new solar generation will be financed by a tax equity partner, which is discussed in “IPL and WPL Solar Project Tax Equity Financing” in “ Liquidity and Capital Resources .” In addition, Alliant Energy completed the construction and acquisition of approximately 1,200 MW of wind generation in aggregate (approximately 1,000 MW at IPL and approximately 200 MW at WPL) from 2018 through 2020.

Clean Energy Blueprint

Alliant Energy has developed a Clean Energy Blueprint, or its cleaner energy strategy, as a guide to meet customer demand for affordable, safe, reliable and sustainable energy in Iowa and Wisconsin.

This strategy includes the planned development and acquisition of additional renewable energy, including approximately 1,100 MW of solar generation at WPL with in-service dates in 2022-2024, approximately 275 MW of battery storage at WPL with in-service dates in 2024 and 2025, approximately 400 MW of solar generation at IPL with in-service dates in 2023 and 2024 and approximately 75 MW of battery storage at IPL with in-service dates in 2024.

In order to support reliable and sustainable energy and meet the MISO’s new seasonal resource adequacy requirements, Alliant Energy, IPL and WPL continue to evaluate additional opportunities for renewable generation, distributed energy resources and natural gas resources, as well as repower existing wind farms.

Estimated capital expenditures for these planned projects for 2023 through 2026 are included in the “Renewables and battery storage” line in the construction and acquisition table in “ Liquidity and Capital Resources .” These estimates include current expectations for higher costs for various projects, as supply constraints and commodity inflation continue to be prevalent in the solar market.

Table of Co ntents

addition, Alliant Energy completed the construction and acquisition of approximately 1,200 MW of wind generation in aggregate (approximately 1,000 MW at IPL and approximately 200 MW at WPL) from 2018 through 2020.

WPL’s Solar Generation and Distributed Energy Resources - In June 2021, WPL received an order from the PSCW for its first CA authorizing WPL to acquire, own, and operate 675 MW of new solar generation in the following Wisconsin counties:

Grant (200 MW), Sheboygan (150 MW), Wood (150 MW), Jefferson (75 MW), Richland (50 MW) and Rock (50 MW).

In July 2021, WPL notified the PSCW that it currently expects estimated construction costs and related rate base additions associated with its 675 MW of new solar generation will exceed amounts approved by the PSCW in June 2021 by approximately 7-10%.

In September 2021 and January 2022, WPL filed revised estimated construction costs and related rate base additions for its second CA with the PSCW for approval to acquire, construct, own, and operate up to 414 MW of new solar generation in the following Wisconsin counties:

In June 2022, WPL received an order from the PSCW for its second CA authorizing WPL to acquire, construct, own, and operate up to 414 MW of new solar generation in the following Wisconsin counties:

Dodge (150 MW), Waushara (99 MW), Rock (65 MW), Grant (50 MW) and Green (50 MW).

These projects in the first and second CAs are expected to be placed in service in 2022 and 2023.

The 1,089 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 early 2023, and Columbia Unit 1 by the end of 2023 and Columbia Unit 2 by the end of 2024 (595 MW in aggregate), which are the last coal-fired EGUs at WPL.

The retirement of these coal-fired EGUs supports Alliant Energy’s strategy, which is focused on meeting its customers’ energy needs in an economical, efficient, reliable and sustainable manner.

As a result of WPL’s neighboring utilities’ anticipated purchase of a partial ownership interest in West Riverside and any requirements resulting from MISO’s resource adequacy proposal that was issued in 2021, WPL anticipates additional capacity needs by 2024, which is expected to result in additional renewable energy resources and energy storage systems.

WPL currently expects to request approval from the PSCW in 2022 for up to 300 MW of additional capacity.

IPL’s Solar Generation and Distributed Energy Resources - In November 2021, IPL filed for advance rate-making principles with the IUB for up to 400 MW of solar generation with in-service dates in 2023 and 2024 and approximately 75 MW of battery storage in 2024.

The advance rate-making principles filing included requests for a fixed cost cap of $1,575/kilowatt, including AFUDC and transmission upgrade costs among other costs, and a return on common equity of 11.40%, and proposes that a portion of the construction be financed by tax equity partners.

In addition, the filing included a request that any costs incurred in excess of the cost cap be incorporated into rates if determined to be reasonable and prudent.

The 400 MW of new solar generation and 75 MW of battery storage would help replace a portion of the energy and capacity expected to be eliminated with the planned retirement of the coal-fired Lansing Generating Station (275 MW) by the end of 2022 and the expected reduction of energy and capacity resulting from the December 2021 fuel switch of the Burlington Generating Station (212 MW) from coal to natural gas.

The Wood, Richland and Rock County projects were placed in service in 2022, and the remaining projects in the first and second CAs are expected to be placed in service in 2023 and 2024.

The 1,089 MW of new solar generation is expected to replace energy and capacity being eliminated with the planned retirements of the coal-fired Edgewater Generating Station (414 MW) by June 1, 2025, and Columbia Units 1 and 2 (595 MW in aggregate) by June 1, 2026, which are the last coal-fired EGUs at WPL.

The retirement of these coal-fired EGUs supports Alliant Energy’s strategy, which is focused on meeting its customers’ energy needs in an affordable, safe, reliable and sustainable manner.

In September 2022, WPL filed a request with the PSCW for approval to construct, own and operate 175 MW of battery storage, with 100 MW and 75 MW at the Grant County and Wood County solar projects, respectively, with in-service dates in 2024.

In January 2023, WPL filed a request with the PSCW for approval to construct, own and operate approximately 99 MW of battery storage at the Edgewater Generating Station, with an in-service date in 2025.

The advance rate-making principles filing included requests for a fixed cost cap, including AFUDC and transmission upgrade costs among other costs, and a return on common equity of 11.40%, and proposed that a portion of the construction be financed by tax equity partners.

In September 2022, IPL provided the IUB with a summary of the Inflation Reduction Act of 2022, as well as an economic analysis indicating full ownership for these planned solar and battery storage projects is currently expected to result in more cost benefits for its customers compared to previous plans to utilize tax equity financing.

In November 2022, the IUB denied these advance rate-making principles filings and IPL requested reconsideration of the IUB’s decision.

In December 2022, the IUB issued an order granting reconsideration of 200 MW of solar generation, and denied reconsideration of the other 200 MW of solar generation and 75 MW of battery storage.

In January 2023, IPL filed additional information with the IUB related to the 400 MW of solar generation and 75 MW of battery storage, including a revised fixed cost cap of $1,845/kilowatt, based on updated materials, labor and shipping costs.

In addition, IPL filed a request for judicial review in January 2023 regarding the denial of advance rate-making principles for the other 200 MW of solar generation and 75 MW of battery storage.

In February 2023, the IUB issued an order stating that it will not issue a decision on the advance rate-making principles for the 200 MW of solar that was granted reconsideration until it receives clarity regarding its authority to issue the advance rate-making principles while the judicial review is also pending.

IPL believes these solar generation and battery storage projects are in the best interests of its customers, and if advance rate-making principles are not approved by the IUB or approval by the IUB is expected to be delayed, IPL may decide to proceed with constructing the solar generation and battery storage subject to other applicable approvals (such as a GCU Certificate), and seek recovery in future rate reviews.

The 400 MW of new solar generation and 75 MW of battery storage would help replace a portion of the energy and capacity expected to be eliminated with the planned retirement of the coal-fired Lansing Generating Station (275 MW) in the first half of 2023 and the reduction of energy and capacity resulting from the December 2021 fuel switch of the Burlington Generating Station (212 MW) from coal to natural gas.

In addition, IPL’s plans include additional renewables and distributed energy resources, including community solar and energy storage systems, to add energy and capacity.

Complementary Generation Investments

New MISO Seasonal Resource Adequacy Process - In August 2022, FERC approved MISO’s proposal to change its resource adequacy process establishing capacity planning reserve margin and capacity accreditation requirements effective with the 2023/2024 MISO Planning Year, to help ensure the reliability of electricity in the MISO region.

The process will change from the current Summer-based annual construct to four distinct seasons to help ensure the continued reliability of the electric transmission grid throughout each year.

FERC’s approval also establishes planning reserve margin requirements for all market participants on a seasonal basis and determines a seasonal accredited capacity value for certain classes of generating resources, including higher accredited capacity for wind generation during the Spring, Fall and Winter seasons and higher accredited capacity for solar generation during the Summer season.

Alliant Energy, IPL and WPL are currently unable to predict with certainty the future outcome or impact of these matters, but plan to construct and/or acquire additional renewable, battery and natural gas resources to meet the requirements of the new seasonal resource adequacy process and have reflected the estimated capital expenditures for these projects in the “Renewables and battery storage” and “Other” Generation lines in the construction and acquisition table in “ Liquidity and Capital Resources .”

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WPL’s West Riverside Natural Gas-fired Generating Station - In 2020, WPL completed the construction of West Riverside, a 723 MW natural gas-fired combined-cycle EGU in Beloit, Wisconsin.

WPL entered into agreements with neighboring utilities and electric cooperatives that provide each of them options to purchase a partial ownership interest in West Riverside.

purchase price for such options is based on the ownership interest acquired and the net book value of West Riverside on the date of the purchase.

The exercise of the WPSC and MGE options is subject to PSCW approval, which is currently expected by early 2023, and the timing and ownership amounts of the options are as follows:

The purchase price for such options is based on the ownership interest acquired and the net book value of West Riverside on the date of the purchase.

The timing and ownership amount of the options are as follows:

Counterparty Option Amount and Timing

Wisconsin Public Service Corporation (WPSC) 100 MW were exercised January 2022;

additionally, up to 100 MW may be exercised between May 15, 2022 and May 15, 2024 (a)

Madison Gas and Electric Company (MGE) 25 MW were exercised January 2022;

additionally, up to 25 MW may be exercised between May 15, 2022 and May 15, 2025

Wisconsin Public Service Corporation (WPSC) 100 MW were exercised January 2022 and are pending PSCW approval;

additionally, up to 100 MW may be exercised prior to May 16, 2024 subject to PSCW approval (a)

Madison Gas and Electric Company (MGE) 25 MW were exercised January 2022 and approved by the PSCW in December 2022;

additionally, up to 25 MW may be exercised prior to May 16, 2025 subject to PSCW approval

Electric cooperatives Approximately 60 MW were acquired January 2018

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Plant Retirements and Fuel Switching - The current strategy includes the retirement, or fuel switch from coal to natural gas, of various EGUs in the next several years.

In December 2021, completed the fuel switch of the Burlington Generating Station (212 MW) from coal to natural gas.

IPL currently expects to retire the coal-fired Lansing Generating Station (275 MW) by the end of 2022.

WPL currently expects to retire the coal-fired Edgewater Generating Station (414 MW) by early 2023, Columbia Unit 1 by the end of 2023 and Columbia Unit 2 by the end of 2024.

IPL currently expects to retire the coal-fired Lansing Generating Station (275 MW) in the first half of 2023, and fuel switch or retire Prairie Creek Units 1 and 3 (65 MW in aggregate) by December 31, 2025.

WPL currently expects to retire the coal-fired Edgewater Generating Station (414 MW) by June 1, 2025, and Columbia Units 1 and 2 (595 MW in aggregate) by June 1, 2026.

Alliant Energy, IPL and WPL are working with MISO, state regulatory commissions and other regulatory agencies, as required, to determine the timing of these actions, which are subject to change depending on operational, regulatory, market and other factors.

Refer to Note 3 for additional details on these EGUs.

Environmental Stewardship - Alliant Energy’s environmental stewardship is focused on meeting its customers’ energy needs affordably, safely, reliably and sustainably.

Alliant Energy proactively considers future environmental compliance requirements and proposed regulations in its planning, decision-making, construction and ongoing operations activities.

Alliant Energy is focused on executing a long-term strategy to deliver reliable and affordable energy with lower emissions independent of changing policies and political landscape.

To achieve these long-term goals, Alliant Energy will transition away from coal-fired EGUs by incorporating renewable energy, distributed energy resources, energy efficiency, demand response, natural gas-fired EGUs and other technologies such as energy storage.

Alliant Energy’s voluntary environmental-related goals and achievements include the following:

• Exceeded its 2020 targets by reducing air emissions for sulfur dioxide by over 90%, nitrogen oxides by over 80% and mercury by over 90% from 2005 levels.

• By 2040, eliminate all coal-fired EGUs from its generating fleet.

• By 2050, achieve an aspirational goal of net-zero CO2 emissions from the electricity it generates.

Other Customer-focused Investments

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Estimated capital expenditures for expected and current electric and gas distribution infrastructure projects for 2023 through 2026 are included in the “Electric and gas distribution systems” lines in the construction and acquisition expenditures table in “ Liquidity and Capital Resources .”

Fiber Optic Telecommunication Network - Alliant Energy is currently installing fiber optic routes between its facilities to enhance its communications network to improve resiliency and reliability of, and enable and strengthen, the integrated grid network to help serve its customers.

Gas Pipeline Expansion - IPL and WPL currently expect to make investments to extend various gas distribution systems to provide natural gas to unserved or underserved areas in their service territories.

Gas Pipeline Safety - In 2019, the Pipeline and Hazardous Materials Safety Administration published a final rule that updates safety requirements for gas transmission pipelines, and various updated procedures were implemented in 2020.

Plans to address certain requirements for specific pipelines were developed and implemented, and remediation efforts must be completed by July 2035.

In anticipation of these rule changes, Alliant Energy, IPL and WPL have been proactively replacing certain of IPL’s transmission pipelines and making modifications to certain of WPL’s transmission pipelines.

Alliant Energy, IPL, and WPL also continue to evaluate the impact of this final rule and resulting remediation plans on their financial condition and results of operations.

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Gas Pipeline Safety - The Pipeline and Hazardous Materials Safety Administration published various final rules from 2019 through 2022 that updated safety requirements for gas transmission pipelines, and updated procedures were implemented to address these rules.

Plans to address certain requirements for specific pipelines were developed and implemented, with identified remediation efforts to be completed by July 2035.

In anticipation of these rule changes, Alliant Energy, IPL and WPL have been proactively replacing certain of IPL’s transmission pipelines, making modifications to certain of WPL’s transmission pipelines, and updating practices for assessment and operation of these pipelines.

Alliant Energy, IPL, and WPL also continue to evaluate the impact of these final rules and resulting remediation plans on their financial condition and results of operations.

Technology - Alliant Energy, IPL and WPL currently plan to make investments in technology to enhance productivity and efficiency through automation, customer self-service and telework.

Estimated capital expenditures for expected and current technology projects for 2023 through 2026 are included in the “Other” line in the construction and acquisition expenditures table in “ Liquidity and Capital Resources .”

Non-utility business - Alliant Energy continues to explore growth of its Travero businesses and other limited scope opportunities outside of, but complimentary to, Alliant Energy’s core utility business.

Non-utility business - Alliant Energy continues to explore growth of its Travero businesses and other limited scope opportunities outside of, but complementary to, Alliant Energy’s core utility business.

This non-utility strategy continues to evolve through exploration of modest strategic opportunities that are accretive to earnings and cash flows.

Retail Base Rate Filings - Base rate changes reflect both returns on additions to infrastructure and recovery of changes in costs incurred or expected to be incurred.

Retail Base Rate Filings - Base rate changes reflect both returns on additions to infrastructure and recovery of changes in costs incurred or expected to be incurred to provide electric and gas service to retail customers.

Given that a portion of the rate changes will offset changes in costs, revenues from rate changes should not be expected to result in an equal change in net income for either IPL or WPL.

WPL’s Retail Electric and Gas Rate Reviews (2022/2023 Forward-looking Test Period) - In December 2021, the PSCW issued an order authorizing annual base rate increases of $114 million and $15 million for WPL’s retail electric and gas customers, respectively, covering the 2022/2023 forward-looking Test Period, which was based on a stipulated agreement between WPL and certain intervenor groups.

The key drivers for the annual base rate increases include higher retail fuel-related costs in 2022, lower excess deferred income tax benefits in 2022 and 2023 and revenue requirement impacts of increasing electric and gas rate base, including investments in solar generation.

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Retail electric rate changes were effective on January 1, 2022 and extend through the end of 2023.

Retail gas rate changes were effective on January 1, 2022 and extend through the end of 2022.

WPL expects to file a limited reopener by August 2022 to adjust retail gas rates for the 2023 forward-looking Test Period, which will be limited to changes in weighted average cost of capital, updated depreciation rates and modifications to certain regulatory asset and regulatory liability amortizations.

Retail gas rate changes were effective from January 1, 2022 through the end of 2022.

In December 2022, the PSCW issued an order authorizing an additional annual base rate increase of $9 million for WPL’s retail gas customers, covering the 2023 forward-looking Test Period, which reflects changes in weighted average cost of capital, updated depreciation rates and modifications to certain regulatory asset and regulatory liability amortizations.

These retail gas rate changes were effective on January 1, 2023 and extend through the end of 2023.

WPL’s settlement extends, with certain modifications, an earnings sharing mechanism through 2023.

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WPL must defer 50% of its excess earnings between 10.25% and 10.75%, and 100% of any excess earnings above 10.75%.

Through 2023, any such deferral is required to be offset against the remaining net book value of Edgewater Unit 5, which is currently expected to be retired by early 2023.

IPL’s Retail Electric and Gas Rate Reviews (2020 Forward-looking Test Period) - In 2019, IPL filed retail electric and gas rate review requests with the IUB covering the 2020 forward-looking Test Period.

In January 2020, IPL received an order from the IUB approving IPL’s proposed settlement for its retail electric rate review.

Final retail electric rates were effective February 26, 2020.

In December 2019, IPL received an order from the IUB approving IPL’s proposed settlement for its retail gas rate review.

Final retail gas rates were effective January 10, 2020.

In 2021, the IUB issued orders for IPL’s 2020 forward-looking Test Period electric and gas subsequent proceedings, which compared actual revenues and costs to those initially forecasted by IPL, and authorized IPL to main its current retail electric and gas rates.

Refer to Note 2 for details.

Through 2023, any such deferral is required to be offset against the remaining net book value of Edgewater Unit 5, which is currently expected to be retired by June 1, 2025.

WPL’s Retail Fuel-related Rate Filing (2021 Forward-looking Test Period) - In August 2022, the PSCW authorized WPL to collect $37 million in 2023 from its retail electric customers, plus interest, for an under-collection of fuel-related costs incurred by WPL in 2021 that were higher than fuel-related costs used to determine rates for such period.

WPL’s Retail Fuel-related Rate Filing (2023 Forward-looking Test Period) - In December 2022, the PSCW authorized WPL to collect $47 million in higher rates in 2023 from its retail electric customers to reflect an increase in expected fuel-related costs for 2023 compared to WPL’s approved 2022 fuel-related costs.

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Rate Review Details - Details related to IPL’s and WPL’s key jurisdictions were as follows:

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The PSCW provides a return on selected CWIP and a cash working capital allowance by adjusting the percentage return on rate base.

Planned Rate Reviews - WPL currently expects to file a retail electric and gas rate review with the PSCW in the second quarter of 2023 for the 2024/2025 forward-looking Test Period.

The key drivers for the anticipated filing include revenue requirement impacts of increasing electric and gas rate base, including investments in solar generation and battery storage.

Any rate changes granted from this pending request are expected to be effective on January 1, 2024, with a decision from the PSCW expected by the end of 2023.

IPL currently expects to file a retail electric and gas rate review with the IUB by the first half of 2024.

The key drivers for the anticipated filing include revenue requirement impacts of increasing electric and gas rate base, including investments in solar generation and battery storage.

LEGISLATIVE MATTERS

In August 2022, the Inflation Reduction Act of 2022 was enacted.

The most significant provisions of the new legislation for Alliant Energy, IPL and WPL relate to a 10-year extension of tax credits for clean energy projects, a new production tax credit eligible for solar projects, a new stand-alone investment tax credit for battery storage projects and the right to transfer future renewable credits to other corporate taxpayers.

The new legislation also includes a requirement for corporations with income over $1 billion to pay a 15% minimum tax;

however, Alliant Energy is currently below this income level.

Alliant Energy, IPL and WPL currently expect to utilize various provisions of the new legislation to enhance the tax benefits expected from their announced solar and battery storage projects, including transferring the future tax credits from such projects to other corporate taxpayers and opting to retain full ownership of such projects instead of financing a portion of the projects with tax equity partners.

Compared to previous plans to utilize tax equity financing, the impact of these changes is expected to result in more cost benefits for IPL's and WPL's customers, higher rate base amounts, additional financing needs expected to be satisfied with additional long-term debt and common stock issuances, and improvements in long-term cash flows over the life of the solar and battery storage projects.

Refer to Note 12 for discussion of Iowa tax reform enacted in March 2022.

In November 2021, the Infrastructure Investment and Jobs Act (IIJA Act) was enacted.

The most significant provisions of the IIJA Act for Alliant Energy relate to a variety of infrastructure-related priorities, including transportation, environmental, energy and broadband infrastructure.

In addition, the IIJA Act is intended to accelerate research, development, demonstration and deployment of carbon-free technologies, including hydrogen and carbon capture and storage.

In March 2021, the American Rescue Plan Act of 2021 (Act) was enacted.

The most significant provision of the Act for Alliant Energy is reduced minimum pension plan funding requirements, which Alliant Energy adopted in August 2021.

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provides additional funding to the Low Income Home Energy Assistance Program, which assists certain of Alliant Energy’s customers with managing their energy costs, as well as provides financial support for certain of Alliant Energy’s residential, small business and non-profit customers.

In March 2020, the Coronavirus Aid, Relief, and Economic Security Act (CARES Act) was enacted.

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The CARES Act also provides additional funding to the Low Income Home Energy Assistance Program, which assists certain of Alliant Energy’s customers with managing their energy costs, as well as financial support for certain of Alliant Energy’s residential, small business and non-profit customers.

In December 2020, the Coronavirus Response and Relief Supplemental Appropriations Act of 2021 (CRRSA) was enacted.

The most significant provision of the CRRSA Act for Alliant Energy relates to the extension of certain renewable tax credits, and as a result, Alliant Energy will evaluate additional opportunities for repowering of its existing wind farms and additional solar projects beyond 2023.

The CRRSA Act also provides additional funding to the Low Income Home Energy Assistance Program, as well as financial support for certain of Alliant Energy’s residential, small business and non-profit customers.

In March 2021, the American Rescue Plan Act of 2021 (Act) was enacted.

The most significant provision of the Act for Alliant Energy is reduced minimum pension plan funding requirements, which Alliant Energy adopted in August 2021.

The Act also provides additional funding to the Low Income Home Energy Assistance Program, which assists certain of Alliant Energy’s customers with managing their energy costs, as well as provides financial support for certain of Alliant Energy’s residential, small business and non-profit customers.

In April 2021, legislation was enacted in Iowa prohibiting counties and cities from regulating the sale of natural gas and propane, which supports IPL’s ability to provide gas utility service to a diversified base of retail customers and industries.

In November 2021, the Infrastructure Investment and Jobs Act (IIJA Act) was enacted.

In addition, the IIJA Act is intended to accelerate research, development, demonstration and deployment of carbon-free technologies, including hydrogen and carbon capture and storage.

LIQUIDITY AND CAPITAL RESOURCES

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As summarized below, Alliant Energy, IPL and WPL believe they have the ability to generate and obtain adequate amounts of cash to meet their requirements and plans for cash in the next 12 months and beyond.

COVID-19 Considerations - Refer to “ Overview ” in MDA for discussion of COVID-19 and the impacts on Alliant Energy’s, IPL’s and WPL’s liquidity and capital resources.

Liquidity Position - At December 31, 2022, Alliant Energy had $20 million of cash and cash equivalents, $358 million ($148 million at the parent company, $100 million at IPL and $110 million at WPL) of available capacity under the single revolving credit facility and $30 million of available capacity at IPL under its sales of accounts receivable program.

Capital Structure - Alliant Energy, IPL and WPL plan to maintain debt-to-total capitalization ratios that are consistent with investment-grade credit ratings.

IPL and WPL expect to maintain capital structures consistent with their authorized levels.

IPL and WPL expect to maintain capital structures consistent with the authorized levels approved by regulators.

Capital structures as of December 31, 2022 were as follows (Common Equity (CE);

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Alliant Energy, IPL and WPL intend to manage their capital structures and liquidity positions in such a way that facilitates their ability to raise funds reliably and on reasonable terms and conditions, while maintaining capital structures consistent with those approved by regulators.

In addition to capital structures, other important factors used to determine the characteristics of future financings include financial coverage ratios, capital spending plans and solar construction that is expected to be partially financed by tax equity partners, regulatory orders and rate-making considerations, levels of debt imputed by rating agencies, market conditions, the impact of tax initiatives and legislation, and any potential proceeds from asset sales.

In addition to capital structures, other important factors used to determine the characteristics of future financings include financial coverage ratios, capital spending plans, regulatory orders and rate-making considerations, levels of debt imputed by rating agencies, market conditions, the impact of tax initiatives and legislation, and any potential proceeds from asset sales.

The PSCW factors certain imputed debt adjustments, including certain lease obligations, in establishing a regulatory capital structure as part of WPL’s retail rate reviews.

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Capital needed to retire debt and fund capital expenditures related to large strategic projects is expected to be met primarily through external financings.

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

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Alliant Energy IPL WPL

DAEC PPA amendment buyout payment in 2020 (Refer to Note 2 )

Credits issued to IPL’s retail electric customers in 2020 through its transmission cost rider for amounts previously collected in rates (Refer to Note 2 )

Increased collections from IPL’s and WPL’s retail customers caused by temperature impacts on electric and gas sales 13 10 3

Changes in levels of production fuel 4 21 (17)

Timing of WPL’s fuel-related cost recoveries from retail electric customers ($80) $— ($80)

Changes in the sales of accounts receivable at IPL (41) (41) —

Timing of WPL’s fuel-related cost recoveries from customers (27) — (27)

Refunds received in 2020 related to the MISO transmission owner return on equity complaint FERC orders (20) (15) (5)

Credits issued to IPL’s retail electric customers in 2021 through its transmission cost rider for refunds received in 2020 for MISO transmission owner return on equity complaints (14) (14) —

Changes in interest payments (39) (10) (10)

Changes in levels of production fuel (19) (16) (3)

Changes in levels of gas stored underground (15) — (15)

Lower (higher) contributions to qualified defined benefit pension plans (13) (33) 18

Changes in income taxes paid/refunded (3) (11) (18)

Higher collections from WPL’s retail electric and gas base rate increases 121 — 121

Changes in cash collateral and deposit balances at Corporate Services 38 — —

Increased collections from IPL’s and WPL’s retail customers caused by temperature impacts on electric and gas sales 17 10 7

Timing of intercompany payments and receipts — 7 (26)

Other (primarily due to other changes in working capital) (62) 24 (66)

($96) ($70) ($72)

Income Tax Payments and Refunds - Income tax (payments) refunds, including refunds of alternative minimum tax credits, were as follows (in millions):

IPL $47 ($18)

Income Tax Payments and Refunds - Income tax (payments) refunds were as follows (in millions):

WPL (56) (38)

Other subsidiaries 14 (12)

Alliant Energy ($6) ($3)

Alliant Energy, IPL and WPL currently do not expect to make any significant federal income tax payments through 2023 based on their current federal net operating loss and credit carryforward positions.

While no significant federal income tax payments through 2023 are expected to occur, some tax payments and refunds may occur for state taxes and between consolidated group members (including IPL and WPL) under the tax sharing agreement between Alliant Energy and its subsidiaries.

Alliant Energy, IPL and WPL currently do not expect to make any significant federal income tax payments over the next few years based on their current credit carryforward positions;

however, some tax payments and refunds may occur for state taxes and between consolidated group members (including IPL and WPL) under the tax sharing agreement between Alliant Energy and its subsidiaries.

Refer to Note 12 for discussion of the carryforward positions.

Pension Plan Contributions - Alliant Energy, IPL and WPL currently expect to make $2 million, $0 and $0 of pension plan contributions in 2022, respectively, based on the funded status and assumed return on assets for each plan as of the December 31, 2021 measurement date.

As discussed in “ Legislative Matters ,” the Inflation Reduction Act of 2022 provides the right to transfer future renewable tax credits to other corporate taxpayers, which is expected to result in future cash flows from operating activities for Alliant Energy, IPL and WPL beginning as early as 2023.

Pension Plan Contributions - Alliant Energy, IPL and WPL currently expect to make $12 million, $1 million and $10 million of pension plan contributions in 2023, respectively, based on the funded status and assumed return on assets for each plan as of the December 31, 2022 measurement date.

Refer to Note 13(a) for discussion of pension plan contributions in 2022 and the current funded levels of pension plans.

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Changes in the amount of cash receipts on sold receivables 96 96 —

Refund from ATC in 2020 for construction deposits WPL previously provided to ATC for transmission network upgrades for West Riverside (42) — (42)

Other 21 16 17

($205) $124 ($317)

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

(a) Largely due to higher expenditures for WPL’s solar generation.

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Construction and Acquisition Expenditures - Construction and acquisition expenditures and financing plans are reviewed, approved and updated as part of the strategic planning process.

Changes may result from a number of reasons, including regulatory requirements, changing legislation, not obtaining favorable and acceptable regulatory approval on certain projects, improvements in technology and improvements to ensure reliability of the electric and gas distribution systems.

Changes may result from a number of reasons, including regulatory requirements, changing legislation, not obtaining favorable and acceptable regulatory approval on certain projects, improvements in technology and improvements to ensure resiliency and reliability of the electric and gas distribution systems.

Alliant Energy, IPL and WPL have not yet entered into contractual commitments relating to the majority of their anticipated future construction and acquisition expenditures.

As a result, they have some discretion with regard to the level and timing of these expenditures.

The table below summarizes anticipated construction and acquisition expenditures (in millions), which are focused on the transition to cleaner energy and strengthening the resiliency of Alliant Energy’s, IPL’s and WPL’s electric grid.

The table below summarizes anticipated construction and acquisition expenditures (in millions), which are focused on the transition to cleaner energy and strengthening the resiliency and reliability of IPL’s and WPL’s electric grid.

Cost estimates represent Alliant Energy’s, IPL’s and WPL’s portion of construction expenditures and exclude AFUDC and capitalized interest, if applicable.

Such estimates do not reflect the assumption that a portion of the construction is expected to be financed by tax equity partners, which is described in more detail below in “IPL and WPL Solar Project Tax Equity Financing.” Refer to “ Customer Investments ” for further discussion of certain key projects impacting construction and acquisition plans related to the utility business.

Refer to “ Customer Investments ” for further discussion of certain key projects impacting construction and acquisition plans related to the utility business.

Alliant Energy IPL WPL

2023 2024 2025 2026 2023 2024 2025 2026 2023 2024 2025 2026

Renewable projects $845 $980 $1,135 $800 $80 $150 $505 $450 $765 $830 $630 $350

Renewables and battery storage $900 $1,205 $725 $1,060 $325 $625 $260 $670 $575 $580 $465 $390

Other 100 315 490 335 55 55 70 100 45 260 420 235

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$1,850 $2,410 $2,020 $2,195 $780 $1,120 $715 $1,135 $930 $1,150 $1,205 $955

Alliant Energy’s and IPL’s construction and acquisition expenditures for renewable projects in 2022 through 2024 include approximately $300 million in aggregate, a portion of which is expected to be reflected as “Other” cash flows used for investing activities in Alliant Energy’s and IPL’s cash flows.

Renewables and Battery Storage - Alliant Energy, IPL and WPL continue to evaluate potential impacts from cost pressures prevalent in the solar generation and battery storage markets on the timing and estimated costs for IPL’s and WPL’s planned development and acquisition of additional renewable energy, which could impact their anticipated future construction and acquisition expenditures.

Refer to “ Customer Investments ” for further discussion of regulatory filings with the IUB and PSCW related to future renewable and battery storage projects.

West Riverside Options - WPL entered into agreements with neighboring utilities that provide them options to purchase a partial ownership interest in West Riverside.

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Alliant Energy IPL WPL

Lower net proceeds from issuance of long-term debt ($650) ($100) ($50)

Lower net proceeds from common stock issuances (219) — —

Higher (lower) net proceeds from issuance of long-term debt $738 ($300) $288

Payments to redeem cumulative preferred stock of IPL in 2021 200 200 —

Higher common stock dividends (26) (164) (8)

Lower payments to retire long-term debt 649 200 150

Net changes in the amount of commercial paper outstanding 1 — 75

Higher payments to retire long-term debt (625) — (250)

(Higher) lower common stock dividends (25) 79 (8)

Higher (lower) capital contributions from IPL’s and WPL’s parent company, Alliant Energy — (50) 285

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$301 ($57) $393

IPL and WPL Solar Project Tax Equity Financing - IPL and WPL each propose to own and operate their planned solar projects, discussed in “ Cust omer Investments ,” which are currently expected to qualify for 26% to 30% investment tax credits, through a tax equity partnership, with approximately 25% to 45% of the construction costs financed with capital from the tax equity partner.

This would allow IPL’s and WPL’s customers to share the costs of the solar projects with an investment partner for 10 years or less, while ensuring their customers receive energy, capacity, and renewable energy credit benefits from the projects.

IPL and 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.

Assuming a portion of the construction costs are financed by the tax equity partner, IPL would receive approximately $25 million in 2023, $200 million in 2024 and $60 million in 2025 from the tax equity partner, and WPL would receive approximately $165 million in 2022, $420 million in 2023, $230 million in 2024 and $190 million in 2025 from the tax equity partner.

Changes to proposed solar project tax equity financing may result from a number of reasons, including changing legislation.

IPL and WPL would expect to include their portion of capital expenditures, less the amounts financed by the tax equity partner, in their respective rate base.

FERC and Public Utility Holding Company Act Financing Authorizations - Under the Public Utility Holding Company Act of 2005, FERC has authority over the issuance of utility securities, except to the extent that a public utility’s primary state regulatory commission has retained jurisdiction over such matters.

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State Regulatory Financing Authorizations - In 2017, WPL received authorization from the PSCW to have up to $400 million of short-term borrowings and/or letters of credit outstanding at any time through the earlier of the expiration date of WPL’s credit facility agreement (including extensions) or December 2024.

As of December 31, 2021, WPL also had authority to issue up to $700 million of long-term debt securities in aggregate through December 2023 pursuant to a September 2020 PSCW order.

In February 2023, WPL received authorization from the PSCW to issue up to $1.2 billion of long-term debt securities in aggregate through December 2025.

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Shelf Registrations - Alliant Energy, IPL and WPL have current shelf registration statements on file with the SEC for availability to issue unspecified amounts of securities through December 2023.

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Common Stock Issuances - Refer to Note 7 for discussion of common stock issuances by Alliant Energy in 2021 and 2022, and “ Results of Operations ” for discussion of expected issuances of common stock in 2023.

Short-term Debt - In December 2021, Alliant Energy, IPL and WPL entered into a single revolving credit facility agreement, which expires in December 2026 and is discussed in Note 9(a) .

Short-term Debt - In 2021, Alliant Energy, IPL and WPL entered into a single revolving credit facility agreement, which expires in December 2026 and is discussed in Note 9(a) .

There are currently 13 lenders that participate in the credit facility, with respective commitments ranging from $20 million to $130 million.

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The equity component of the capital ratios excludes accumulated other comprehensive income (loss).

Long-term Debt - Refer to Note 9(b) for discussion of issuances and retirements of long-term debt in 2021 and “ Results of Operations ” for discussion of expected issuances of long-term debt in 2022.

In 2020, IPL issued $400 million of 2.3% senior debentures due 2030, and a portion of the proceeds from the issuance was used by IPL to retire its $200 million 3.65% senior debentures that matured in 2020.

In 2020, WPL issued $350 million of 3.65% debentures due 2050, and a portion of the proceeds from the issuance was used by WPL to reduce borrowings under the single revolving credit facility.

In 2020, AEF entered into a $300 million variable-rate term loan credit agreement and used the borrowings under this agreement to retire its $300 million variable-rate term loan credit agreement that expired in 2020.

In 2020, AEF issued $200 million of 1.4% senior notes due 2026, and a portion of the proceeds from the issuance was used to reduce Alliant Energy’s outstanding commercial paper.

Long-term Debt - Refer to Note 9(b) for discussion of issuances and retirements of long-term debt in 2022 and 2023, and “ Results of Operations ” for discussion of expected issuances of long-term debt in 2023.

In 2021, IPL issued $300 million of 3.1% senior debentures due 2051, and the net proceeds from the issuance were used by IPL to retire its cumulative preferred stock in 2021 and for general corporate purposes.

In 2021, WPL issued $300 million of 1.95% green bond debentures due 2031, and an amount in excess of the net proceeds was disbursed for the construction and development of WPL’s wind and solar EGUs.

Impact of Credit Ratings on Liquidity and Collateral Obligations -

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Credit ratings and outlooks as of the date of this report are as follows:

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Standard & Poor’s Ratings Services Moody’s Investors Service

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Senior unsecured long-term debt A A3

Outlook Stable Stable

Outlook Negative Negative

Standard & Poor’s Ratings Services and Moody’s Investors Service issued credit ratings of BBB+ and Baa2, respectively, for the senior notes issued by AEF in 2018, 2020 and 2022 (with Alliant Energy as guarantor).

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The purchase commitment from the third party to which IPL sells its receivables expires in March 2023.

IPL currently expects to amend and extend the purchase commitment.

In 2022 and 2021, IPL evaluated the third party that purchases IPL’s receivable assets under the Receivables Agreement and believes that the third party is a VIE;

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OTHER MATTERS

Market Risk Sensitive Instruments and Positions - Primary market risk exposures are associated with commodity prices, investment prices and interest rates.

Risk management policies are used to monitor and assist in mitigating these market risks and derivative instruments are used to manage some of the exposures related to commodity prices.

Market Risk Sensitive Instruments and Positions - Primary market risk exposures are associated with commodity prices, counterparty credit risk, investment prices and interest rates.

Risk management policies are used to monitor and assist in mitigating these market risks and derivative instruments are used to manage some of the exposures related to commodity prices and interest rates.

Refer to Notes 1(h) and 15 for further discussion of derivative instruments, and Note 1(g) for details of utility cost recovery mechanisms that significantly reduce commodity risk.

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IPL’s electric and gas tariffs and WPL’s wholesale electric and gas tariffs provide for subsequent monthly adjustments to their tariff rates for material changes in prudently incurred commodity costs.

IPL’s and WPL’s rate mechanisms, combined with commodity derivatives, significantly reduce commodity risk associated with their electric and gas margins.

WPL’s retail electric margins have modest exposure to the impact of changes in commodity prices due largely to the current retail recovery mechanism in place in Wisconsin for fuel-related costs.

IPL’s and WPL’s rate mechanisms, combined with commodity derivatives, significantly reduce commodity risk associated with their electric and gas

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WPL’s retail electric margins have exposure to the impact of changes in commodity prices due largely to the current retail recovery mechanism in place in Wisconsin for fuel-related costs.

Counterparty Credit Risk - Alliant Energy, IPL, and WPL are exposed to credit risk related to losses resulting from counterparties’ nonperformance of their contractual obligations.

Alliant Energy, IPL and WPL maintain credit policies intended to minimize overall credit risk and actively monitor these policies to reflect changes and scope of operations.

Alliant Energy, IPL, and WPL conduct credit reviews for all counterparties and employ credit risk controls, such as letters of credit, parental guarantees, master netting agreements and termination provisions.

Credit exposure is monitored, and when necessary, activity with a specific counterparty is limited until credit enhancement is provided.

Distress in the financial markets could increase Alliant Energy’s, IPL’s and WPL’s credit risk.

Investment Price - Alliant Energy, IPL and WPL are exposed to investment price risk as a result of their investments in securities, largely related to securities held by their pension and OPEB plans.

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In addition, Alliant Energy and IPL are exposed to risk resulting from changes in interest rates on cash amounts outstanding under IPL’s sales of accounts receivable program.

Assuming the impact of a hypothetical 100 basis point increase in interest rates on variable-rate borrowings and cash amounts outstanding under IPL’s sales of accounts receivable program at December 31, 2021, Alliant Energy’s, IPL’s and WPL’s annual pre-tax expense would increase by approximately $8 million, $0 and $2 million, respectively.

Assuming the impact of a hypothetical 100 basis point increase in interest rates on variable-rate borrowings and cash amounts outstanding under IPL’s sales of accounts receivable program at December 31, 2022, Alliant Energy’s, IPL’s and WPL’s annual pre-tax expense would increase by approximately $11 million, $1 million and $3 million, respectively.

Refer to Notes 5(b) and 9 for additional information on cash amounts outstanding under IPL’s sales of accounts receivable program, and short- and long-term variable-rate borrowings, respectively.

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Regulatory assets and regulatory liabilities are recognized in accordance with the rulings of applicable federal and state regulators, and future regulatory rulings may impact the carrying value and accounting treatment of regulatory assets and regulatory liabilities.

changes, rate orders issued by the applicable regulatory agencies, historical decisions by such regulatory agencies regarding similar regulatory assets and regulatory liabilities, and subsequent events of such regulatory agencies.

Assumptions and judgments are made each reporting period regarding whether regulatory assets are probable of future recovery and regulatory liabilities are probable future obligations by considering factors such as regulatory environment changes, rate orders issued by the applicable regulatory agencies, historical decisions by such regulatory agencies regarding similar regulatory assets and regulatory liabilities, and subsequent events of such regulatory agencies.

The decisions made by regulatory authorities have an impact on the recovery of costs, the rate of return on invested capital and the timing and amount of assets to be recovered by rates.

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Alliant Energy’s and IPL’s critical assumptions and judgments for 2022 include estimates of qualifying deductions for repairs expenditures and allocation of mixed service costs due to the impact of Iowa rate-making principles on such property-related differences.

Critical assumptions and judgments also include projections of future taxable income used to determine the ability to utilize net operating losses and credit carryforwards prior to their expiration.

Critical assumptions and judgments also include projections of future taxable income used to determine the ability to utilize federal credit carryforwards prior to their expiration.

Refer to Note 12 for further discussion of tax matters.

Effect of Rate-making on Property-related Differences - Alliant Energy’s and IPL’s effective income tax rates are normally impacted by certain property-related differences at IPL for which deferred tax is not recorded in the income statement pursuant to Iowa rate-making principles.

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to Iowa rate-making principles.

Changes in methods or assumptions regarding the amount of IPL’s qualifying repairs expenditures, allocation of mixed service costs, and costs related to retirement or removal of depreciable property could result in a material impact on Alliant Energy’s and IPL’s financial condition and results of operations.

Carryforward Utilization - Significant federal tax credit carryforwards and federal and state net operating loss carryforwards exist for Alliant Energy, IPL and WPL as of December 31, 2021.

Based on projections of current and future taxable income, Alliant Energy, IPL and WPL plan to utilize substantially all of these carryforwards prior to their expiration.

Taxable income must be reduced by federal net operating losses carryforwards prior to utilizing federal tax credit carryforwards.

Alliant Energy does not expect to utilize all of its federal net operating loss carryforwards until 2023, and therefore, currently does not expect to utilize 2002 vintage federal credit carryforwards prior to their expiration in 2022, resulting in valuation allowances that remain as of December 31, 2021.

Federal credit carryforwards generated from 2003 through 2008, which amount to $12 million for Alliant Energy, are expected to be utilized within five years of expiration.

All other federal credit carryforwards and federal net operating loss carryforwards are expected to be utilized more than five years before expiration.

Changes in tax regulations or assumptions regarding current and future taxable income could require changes to valuation allowances in the future resulting in a material impact on financial condition and results of operations.

Carryforward Utilization - Significant federal tax credit carryforwards exist for Alliant Energy, IPL and WPL as of December 31, 2022.

Based on projections of current and future taxable income, Alliant Energy, IPL and WPL plan to utilize all of these carryforwards prior to their expiration.

Federal credit carryforwards generated from 2004 through 2008 are expected to be utilized within five years of expiration.

All other federal credit carryforwards are expected to be utilized more than five years before expiration.

Changes in tax regulations or assumptions regarding current and future taxable income could require valuation allowances in the future resulting in a material impact on financial condition and results of operations.

Long-Lived Assets - Periodic assessments regarding the recoverability of certain long-lived assets are completed when factors indicate the carrying value of such assets may not be recoverable or such assets are planned to be sold.

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The long-lived assets assessed for impairment generally include certain assets within regulated operations that may not be fully recovered from IPL’s and WPL’s customers as a result of regulatory decisions in the future, and assets within non-utility operations that are proposed to be sold or are currently generating operating losses.

Regulated Operations - Alliant Energy’s, IPL’s and WPL’s long-lived assets within their regulated operations that were assessed for impairment and plant abandonment in 2021 included IPL’s and WPL’s generating units subject to early retirement.

Generating Units Subject to Early Retirement - Alliant Energy, IPL and WPL evaluate future plans for their electric generation fleet and have announced the early retirement of certain older and less-efficient EGUs.

Regulated Operations - Alliant Energy’s, IPL’s and WPL’s long-lived assets within their regulated operations that were assessed for impairment and/or plant abandonment in 2022 included IPL’s and WPL’s generating units subject to early retirement and WPL’s solar generation projects recently completed and under construction.

Generating Units Subject to Early Retirement - Alliant Energy, IPL and WPL evaluate future plans for their electric generation fleet and have announced the early retirement of certain EGUs.

When it becomes probable that an EGU will be retired before the end of its useful life, Alliant Energy, IPL and WPL must assess whether the EGU meets the criteria to be considered probable of abandonment.

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If it is probable that regulators will not allow full recovery of and a full return on the remaining net book value of the abandoned EGU, an impairment charge is recognized equal to the difference between the remaining carrying value and the present value of the future revenues expected from the abandoned EGU.

Alliant Energy and IPL concluded that Lansing, and Alliant Energy and WPL concluded that Edgewater Unit 5 and Columbia Units 1 and 2, met the criteria to be considered probable of abandonment as of December 31, 2021.

Alliant Energy and IPL concluded that Lansing (expected to be retired in the first half of 2023), and Alliant Energy and WPL concluded that Edgewater Unit 5 (expected to be retired by June 1, 2025) and Columbia Units 1 and 2 (expected to be retired by June 1, 2026), met the criteria to be considered probable of abandonment as of December 31, 2022.

IPL and WPL are currently allowed a full recovery of and a full return on its respective EGUs from both its retail and wholesale customers, and as a result, Alliant Energy, IPL and WPL concluded that no impairment was required as of December 31, 2022.

Upon retirement of Lansing, which is currently expected in the first half of 2023, IPL anticipates reclassifying the remaining net book value, which was $233 million as of December 31, 2022, from property, plant and equipment to a regulatory asset on Alliant Energy’s and IPL’s balance sheets.

Continued recovery of the remaining net book value of Lansing is expected to be addressed in future rate reviews.

Alliant Energy, IPL and WPL evaluated their other EGUs that are subject to early retirement and determined that no other EGUs met the criteria to be considered probable of abandonment as of December 31, 2022.

Note 3 provides additional details of these assets anticipated to be retired early.

WPL’s Solar Generation Projects Recently Completed and Under Construction - As discussed in “ Customer Investments ,” WPL previously received authorization from the PSCW to acquire, construct, own and/or operate approximately 1,100 MW of new solar generation, which includes various projects in various Wisconsin counties.

In 2022, WPL completed the construction of three solar projects, and the remaining solar projects are currently expected to be placed in service in 2023 and 2024.

Alliant Energy and WPL review property, plant and equipment for possible impairment whenever events or changes in circumstances indicate all or a portion of the carrying value of the assets may be disallowed for rate-making purposes.

If WPL is disallowed recovery of any portion of, or is only allowed a partial return on, the carrying value of the solar generation projects recently completed or under construction, then an impairment charge is recognized.

In July 2021, WPL notified the PSCW that it expected estimated construction costs associated with approximately 675 MW of new solar generation will exceed amounts previously approved by the PSCW by approximately 7-10%.

In addition, the prior authorization received from the PSCW for approximately 1,100 MW of new solar generation assumed that a portion of the construction costs would be financed by a tax equity partner.

Following the enactment of the Inflation Reduction Act of 2022, WPL determined that retaining full ownership of the approximately 1,100 MW of new solar generation is expected to result in more cost benefits for its customers.

Alliant Energy and WPL no longer expect their solar generation project construction costs to be financed with capital from tax equity partners, which would result in higher rate base amounts compared to those previously approved by the PSCW for WPL’s planned approximately 1,100 MW of solar generation.

Alliant Energy and WPL concluded that there was not a probable disallowance of anticipated higher rate base amounts as of December 31, 2022 given construction costs were reasonably and prudently incurred and full ownership of WPL’s planned solar generation is expected to result in more cost benefits for WPL's customers.

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Unbilled Revenues - Unbilled revenues are primarily associated with utility operations.

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Defined Benefit Pension Plans OPEB Plans

Change in Actuarial Assumption Impact on Projected Benefit Obligation at December 31, 2021 Impact on 2022 Net Periodic Benefit Costs Impact on Accumulated Benefit Obligation at December 31, 2021 Impact on 2022 Net Periodic Benefit Costs

Change in Actuarial Assumption Impact on Projected Benefit Obligation at December 31, 2022

Impact on 2023 Net Periodic Benefit Costs

Impact on Accumulated Benefit Obligation at December 31, 2022

Impact on 2023 Net Periodic Benefit Costs

Alliant Energy

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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, the creditworthiness of the other partners, Whiting Petroleum’s emergence from bankruptcy in the third quarter of 2020, and forecasted cash flow expenditures associated with the abandonment obligations based on information made available to Alliant Energy.

Factors considered include market and external data points, the creditworthiness of the other partners, Whiting Petroleum’s emergence from bankruptcy in the third quarter of 2020 as well as subsequent bankruptcy developments, payments by Whiting Petroleum related to abandonment obligations, forecasted cash flow expenditures associated with the abandonment obligations based on information made available to Alliant Energy, and Whiting Petroleum’s business combination with Oasis Petroleum Inc.

in the third quarter of 2022.

Note 1( l ) provides discussion of the adoption of the new accounting standard for credit losses.

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Compared sentence by sentence after normalising whitespace, quotation marks, case and digits, so re-formatting and restated figures do not read as changed language. Wording changes appear as one removal and one addition. The current filing and the prior one are authoritative.

What changed 10-K

Item 7. Management’s Discussion and Analysis