{ "schemaVersion": 1, "organisationId": "O-82f119d8456644948c95f844ecd648e3", "slug": "alliant-energy-corp", "name": "ALLIANT ENERGY CORP", "updatedAt": "2026-10-02T11:58:49.724141Z", "sections": [ { "type": "OVERVIEW", "text": "Alliant Energy Corporation is a U.S. investor-owned utility holding company focused primarily on regulated electric and natural-gas service in the Midwest. Through its subsidiaries Interstate Power and Light (IPL) and Wisconsin Power and Light (WPL), it generates and distributes electricity and distributes or transports natural gas, principally in Iowa and Wisconsin; it also sells electricity wholesale in parts of those states and Illinois. [P89460435][P66857840][P26492315]\n\nThe company describes its core purpose as “to serve customers and build stronger communities.” In 2025, it reported $4.4 billion in operating revenues and 2,948 full- and part-time employees, reflecting a regional U.S. utility business rather than a global operating footprint. [P117050041][https://investors.alliantenergy.com/resources/corporate-fact-sheet/default.aspx]\n[P89460435][P66857840][P26492315][P117050041][https://investors.alliantenergy.com/resources/corporate-fact-sheet/default.aspx]", "updatedAt": "2026-10-02T11:58:49.724141Z" }, { "type": "PRODUCTS", "text": "Alliant Energy’s principal customer products are regulated retail electricity and natural gas, alongside wholesale electricity sales. In 2025, electric revenue was $3.697 billion, including $3.305 billion from retail sales; natural-gas revenue was $525 million, including $472 million from retail sales. [T771213] [T771213] [T771213] [T771213]\n\nCustomer-facing offerings include community-solar subscriptions, the voluntary Renewable Energy Impact program, which lets participants match 1%–100% of their electricity use with renewable energy certificates, and support for rooftop solar and geothermal. [https://www.alliantenergy.com/ways-to-save/community-solar] [https://www.alliantenergy.com/ways-to-save/renewable-energy-impact] [https://www.alliantenergy.com/ways-to-save/generating-your-own-solar] Alliant also offers home energy-saving programs and rebates, Iowa business energy audits and custom incentives, and Wisconsin business energy-efficiency programs with technical and project support. [https://www.alliantenergy.com/ways-to-save/for-your-home] [https://www.alliantenergy.com/ways-to-save/energy-audit-iowa] [https://www.alliantenergy.com/ways-to-save/custom-rebates] [https://www.alliantenergy.com/customer-service/business/wisconsin]\n\nThe company’s electricity-related capabilities include battery storage: a 99 MW battery at the Wever site entered service in November 2025, and additional projects of up to 150 MW at Lansing, 75 MW at Golden Plains, and 75 MW at Whispering Willow–North were approved. [P89502144] Alliant provides customer service for starting, stopping or transferring utility service and publishes bill and rate information and residential rate options. [https://www.alliantenergy.com/customer-service/start-stop-move-service] [https://www.alliantenergy.com/account-and-billing/understanding-bill-rates] [https://www.alliantenergy.com/ways-to-save/residential-rate-options]\n[T771213][T771213][T771213][T771213][P89502144][https://www.alliantenergy.com/ways-to-save/community-solar][https://www.alliantenergy.com/ways-to-save/renewable-energy-impact][https://www.alliantenergy.com/ways-to-save/generating-your-own-solar][https://www.alliantenergy.com/ways-to-save/for-your-home][https://www.alliantenergy.com/ways-to-save/energy-audit-iowa][https://www.alliantenergy.com/ways-to-save/custom-rebates][https://www.alliantenergy.com/customer-service/business/wisconsin][https://www.alliantenergy.com/customer-service/start-stop-move-service][https://www.alliantenergy.com/account-and-billing/understanding-bill-rates][https://www.alliantenergy.com/ways-to-save/residential-rate-options]", "updatedAt": "2026-10-02T11:58:49.724141Z" }, { "type": "GEOGRAPHY", "text": "Alliant Energy’s retail electric and natural-gas operations are in select markets in Iowa, through Interstate Power and Light, and Wisconsin, through Wisconsin Power and Light. At year-end 2025, the utilities served approximately 505,000 electric and 230,000 gas customers in Iowa, and 505,000 electric and 205,000 gas customers in Wisconsin. [P66857840][P26492315] The company’s service area spans about 53,500 square miles across the two states. [https://www.alliantenergy.com/who-we-are/about-alliant-energy]\n\nBeyond its retail footprint, IPL sells wholesale electricity in Iowa and Illinois. Alliant also has generation assets in Minnesota and Iowa outside its Wisconsin retail territory. [P16555210][T1349477] Madison, Wisconsin, is the company’s headquarters. It reported 2,948 full- and part-time employees as of December 31, 2025; a geographic breakdown of employees is not provided in the cited company materials. [https://www.alliantenergy.com/who-we-are/about-alliant-energy][https://investors.alliantenergy.com/resources/corporate-fact-sheet/default.aspx]\n[P66857840][P26492315][https://www.alliantenergy.com/who-we-are/about-alliant-energy][P16555210][T1349477][https://investors.alliantenergy.com/resources/corporate-fact-sheet/default.aspx][https://www.alliantenergy.com/who-we-are/about-alliant-energy][https://investors.alliantenergy.com/resources/corporate-fact-sheet/default.aspx]", "updatedAt": "2026-10-02T11:58:49.724141Z" }, { "type": "SEGMENTS", "text": "Alliant Energy reports two reportable utility segments: **IPL (Interstate Power and Light Company)**, serving electric and natural-gas customers in Iowa, and **WPL (Wisconsin Power and Light Company)**, serving electric and natural-gas customers in Wisconsin. The company also reports “Other” for reconciliation purposes; it is not a reportable segment and includes AEF and subsidiaries, corporate services, the parent company and consolidating adjustments, among other items. [P59769428][P107256404][P15804901]\n\nFor the six months ended June 30, 2026, IPL contributed approximately 48% of consolidated revenue and 40% of net income; WPL contributed approximately 50% of revenue and 49% of net income. “Other” contributed about 2% of revenue and 10% of net income. At June 30, 2026, IPL represented about 51% of consolidated assets and WPL about 44%. Percentages are calculated from the segment amounts in the company’s Q2 2026 filing. [https://www.sec.gov/Archives/edgar/data/352541/000035254126000043/lnt-20260630.htm]\n\nAlliant previously presented utility business segments as electric operations, gas operations and other; its FY2025 annual report explains that this segmentation was changed following adoption of updated segment-disclosure accounting in Q4 2024, with comparative data recast. [P15804901]\n[P59769428][P107256404][P15804901][https://www.sec.gov/Archives/edgar/data/352541/000035254126000043/lnt-20260630.htm]", "updatedAt": "2026-10-02T11:58:49.724141Z" }, { "type": "HISTORY", "text": "Alliant Energy’s corporate roots extend to regional utilities dating to the late 19th century: Iowa Southern Utilities was incorporated in 1890, and a series of mergers and reorganizations led to IES Utilities by 1994. [https://www.alliantenergy.com/-/media/alliant/documents/accountandbilling/ratesandtariffs/iowaelectricrates/preliminarystatement.pdf?hash=B3DC7657AF9E27E8FA9F0247B868B0CC&sc_lang=en] On April 20, 1998, Wisconsin Holdings (WPL), IES Industries and Interstate Power Company merged as Interstate Energy Corporation; the company adopted the Alliant Energy name in 1999. [https://investors.alliantenergy.com/resources/investor-faqs/default.aspx]\n\nIn 2007, subsidiary Interstate Power and Light completed the sale of its electric transmission assets to ITC Midwest, a significant change in the company’s utility asset structure. [https://www.sec.gov/Archives/edgar/data/52485/000089706907002172/0000897069-07-002172.txt] Alliant expanded its wind generation in the following years, bringing its first Wisconsin wind farm, Cedar Ridge, into service in 2008 and Iowa’s 200-MW Whispering Willow East wind farm into service in 2009. [https://www.alliantenergy.com/our-energy/wind/wisconsin-wind/cedar-ridge] [https://www.alliantenergy.com/our-energy/wind/iowa-wind/whispering-willow-east] In 2015, it completed the sale of its Minnesota electric distribution assets to a group of electric cooperatives. [https://investors.alliantenergy.com/News--Presentations/news/news-details/2015/Alliant-Energy-closes-sale-of-its-Minnesota-electric-distribution-assets-to-cooperatives/default.aspx]\n[https://www.alliantenergy.com/-/media/alliant/documents/accountandbilling/ratesandtariffs/iowaelectricrates/preliminarystatement.pdf?hash=B3DC7657AF9E27E8FA9F0247B868B0CC&sc_lang=en][https://investors.alliantenergy.com/resources/investor-faqs/default.aspx][https://www.sec.gov/Archives/edgar/data/52485/000089706907002172/0000897069-07-002172.txt][https://www.alliantenergy.com/our-energy/wind/wisconsin-wind/cedar-ridge][https://www.alliantenergy.com/our-energy/wind/iowa-wind/whispering-willow-east][https://investors.alliantenergy.com/News--Presentations/news/news-details/2015/Alliant-Energy-closes-sale-of-its-Minnesota-electric-distribution-assets-to-cooperatives/default.aspx][https://www.alliantenergy.com/-/media/alliant/documents/accountandbilling/ratesandtariffs/iowaelectricrates/preliminarystatement.pdf?hash=B3DC7657AF9E27E8FA9F0247B868B0CC&sc_lang=en][https://investors.alliantenergy.com/resources/investor-faqs/default.aspx][https://www.sec.gov/Archives/edgar/data/52485/000089706907002172/0000897069-07-002172.txt][https://www.alliantenergy.com/our-energy/wind/wisconsin-wind/cedar-ridge][https://www.alliantenergy.com/our-energy/wind/iowa-wind/whispering-willow-east][https://investors.alliantenergy.com/News--Presentations/news/news-details/2015/Alliant-Energy-closes-sale-of-its-Minnesota-electric-distribution-assets-to-cooperatives/default.aspx]", 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