Item 2. Properties
ITEM 2. PROPERTIES
Alliant Energy - As a holding company, Alliant Energy doesn’t directly own any significant properties other than the stock of its subsidiaries. The principal properties of those subsidiaries are as follows:
IPL and WPL
Electric - At December 31, 2025, IPL’s and WPL’s facilities by primary fuel type were as follows:
IPL Generating
In-service Capacity
Name of Facility and Location Dates in MW (a)
Marshalltown Generating Station (Units 1-3); Marshalltown, IA 2017 666
Emery Generating Station (Units 1-3); Mason City, IA 2004 531
Marshalltown Combustion Turbines (Units 1-3); Marshalltown, IA 1978 155
Burlington Generating Station (Unit 1); Burlington, IA 1968 143
Prairie Creek Generating Station (Unit 4); Cedar Rapids, IA 1967 126
Burlington Combustion Turbines (Units 1-4); Burlington, IA 1994-1996 34
Total Gas 1,655
Upland Prairie (121 Units); Clay and Dickinson Cos., IA 2019 299
Whispering Willow - North (81 Units); Franklin Co., IA 2020 201
Whispering Willow - East (121 Units); Franklin Co., IA 2009 200
Golden Plains (82 Units); Winnebago and Kossuth Cos., IA 2020 200
English Farms (69 Units); Poweshiek Co., IA 2019 172
Richland (53 Units); Sac Co., IA 2020 131
Franklin County (60 Units); Franklin Co., IA 2012 99
Total Wind 1,302
Pleasant Creek (Units 1-2), Linn Co., IA 2024 200
Wever; Lee Co., IA 2024 150
Creston; Union Co., IA 2024 50
Dubuque; Dubuque, IA 2017 5
Marshalltown; Marshalltown, IA 2020 3
Customer-hosted and Community Solar; various locations in IA 2024-2025 18
Total Solar 426
Ottumwa Generating Station (Unit 1); Ottumwa, IA (b) 1981 336
George Neal Generating Station (Unit 4); Sioux City, IA (c) 1979 165
George Neal Generating Station (Unit 3); Sioux City, IA (d) 1975 143
Prairie Creek Generating Station (Units 1 and 3); Cedar Rapids, IA (e) 1958-1997 37
Louisa Generating Station (Unit 1); Louisa, IA (f) 1983 30
Total Coal 711
Lime Creek Combustion Turbines (Units 1-2); Mason City, IA 1991 72
Total Oil 72
Wever; Lee Co., IA 2025 99
Energy Storage; various locations in IA 2019-2023 9
Total Energy Storage 108
Total capacity 4,274
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WPL Generating
In-service Capacity
Name of Facility and Location Dates in MW (a)
Riverside Energy Center (Units 1-3); Beloit, WI 2004 530
West Riverside Energy Center (Units 1-3); Beloit, WI (g) 2020 390
Neenah Energy Facility (Units 1-2); Neenah, WI 2000 296
South Fond du Lac Combustion Turbines (2 Units); Fond du Lac, WI (h) 1994 164
Total Gas 1,380
Bent Tree (122 Units); Freeborn Co., MN 2010-2011 201
Kossuth (56 Units); Kossuth Co., IA 2020 152
Cedar Ridge (41 Units); Fond du Lac Co., WI 2008 68
Forward Wind Energy Center (37 Units); Dodge and Fond du Lac Cos., WI (i) 2008 59
Total Wind 480
Grant County, Grant Co., WI 2024 200
Wood County, Wood Co., WI 2022 150
Onion River, Sheboygan Co., WI 2023 150
Springfield, Dodge Co., WI 2023 100
Wautoma, Waushara Co., WI 2023 99
Crawfish River, Jefferson Co., WI 2023 75
Paddock, Rock Co., WI 2023 65
Bear Creek, Richland Co., WI 2022 50
North Rock, Rock Co., WI 2022 50
Albany, Green Co., WI 2023 50
Beaver Dam, Dodge Co., WI 2023 50
Cassville, Grant Co., WI 2023 50
West Riverside, Beloit, WI (f) 2021 2
Customer-hosted and Community Solar; various locations in WI 2021-2025 11
Total Solar 1,102
Columbia Energy Center (Units 1-2); Portage, WI (j) 1975-1978 596
Edgewater Generating Station (Unit 5); Sheboygan, WI 1985 405
Total Coal 1,001
Prairie du Sac (8 Units); Prairie du Sac, WI 1914-1940 13
Kilbourn (4 Units); Wisconsin Dells, WI 1926-1939 6
Total Hydro 19
Grant County, Grant Co., WI 2025 100
Wood County, Wood Co., WI 2025 75
Energy Storage; various locations in WI 2022-2023 9
Total Energy Storage 184
Total capacity 4,166
(a) Based on the summer installed generating capacity included in MISO’s resource adequacy process for the planning period from June 2025 through May 2026, except for wind facilities, solar facilities and energy storage, which are based on nameplate capacity.
(b) Represents IPL’s 48% ownership interest, which is operated by IPL.
(c) Represents IPL’s 25.695% ownership interest, which is operated by MidAmerican Energy Company.
(d) Represents IPL’s 28% ownership interest, which is operated by MidAmerican Energy Company.
(e) Subsequent to December 31, 2025, IPL retired Prairie Creek Unit 1 and fuel switched Prairie Creek Unit 3 to natural gas.
(f) Represents IPL’s 4% ownership interest, which is operated by MidAmerican Energy Company.
(g) Represents WPL’s 56.6% ownership interest, which is operated by WPL.
(h) Represents Units 2 and 3, which WPL owns. WPL also operates, but does not own, South Fond du Lac Combustion Turbines Units 1 and 4.
(i) Represents WPL’s 42.64% ownership interest, which is operated by Invenergy Services, LLC.
(j) Represents WPL’s 53.5% ownership interest, which is operated by WPL.
IPL and WPL own overhead electric distribution line, underground electric distribution cable and substation distribution transformers, substantially all of which are located in Iowa for IPL and Wisconsin for WPL.
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Gas - IPL’s and WPL’s gas properties consist primarily of mains and services, meters, regulating and gate stations and other related transmission and distribution equipment. IPL’s and WPL’s gas distribution facilities include gas mains located in Iowa and Wisconsin, respectively.
Other - Refer to Note 9 for information regarding WPL’s lease of the Sheboygan Falls Energy Facility from AEF’s Non-utility Generation business.
Corporate Services - Corporate Services’ property included in “Property, plant and equipment, net” on Alliant Energy’s balance sheet at December 31, 2025 consisted primarily of computer software, and the corporate headquarters building located in Madison, Wisconsin.
AEF - AEF’s principal properties included in “Property, plant and equipment, net” on Alliant Energy’s balance sheet at December 31, 2025 were as follows:
Non-utility Generation - Includes the Sheboygan Falls Energy Facility, a 347 MW, simple-cycle, natural gas-fired facility near Sheboygan Falls, Wisconsin that was placed in service in 2005 and is leased to WPL. The summer installed generating capacity included in MISO’s resource adequacy process for the planning period from June 2025 through May 2026 for the Sheboygan Falls Energy Facility was 298 MW.
Travero - Includes a short-line rail freight service in Iowa; a Mississippi River barge, rail and truck freight terminal in Illinois; and a rail-served warehouse in Iowa.
Development-ready Sites - includes various rail-served and ready-to-build manufacturing and industrial sites throughout Iowa and Wisconsin, with access to various airports, interstate freeways and Alliant Energy’s electric services.