Power plants operated by Interstate Power and Light Co
Interstate Power and Light Co operates 29 power plants in the 2025 EIA-860 data, with 4,537 MW of nameplate capacity, the 55th-largest fleet among the 5,826 operators on file. All of them are in Iowa. Natural gas is 43% of the capacity; the largest site is Ottumwa. Its oldest working unit dates from 1958, at Prairie Creek. Units added from 2020 to 2025 total 960 MW.
- Natural gas1,937 MW43%
- Wind1,302 MW29%
- Coal776 MW17%
- Solar424 MW9.4%
- Oil and petroleum90.2 MW2.0%
- Battery storage7.8 MW0.2%
Capacity by decade it came online
CoalNatural gasOil and petroleumWindSolarBattery storage
Above the line: capacity operating in 2025. Below: capacity retired at these plants.
Plants
| Plant | State | Runs on | Capacity | First unit |
|---|---|---|---|---|
| Ottumwa | Iowa | Coal | 726 MW | 1981 |
| Marshalltown Generating Station | Iowa | Natural gas | 709 MW | 2017 |
| Emery Station | Iowa | Natural gas | 603 MW | 2004 |
| Upland Prairie | Iowa | Wind | 299 MW | 2019 |
| Burlington (IA) | Iowa | Natural gas | 291 MW | 1968 |
| Whispering Willow North | Iowa | Wind | 201 MW | 2020 |
| Golden Plains | Iowa | Wind | 200 MW | 2020 |
| Whispering Willow Wind Farm - East | Iowa | Wind | 200 MW | 2009 |
| Prairie Creek | Iowa | Natural gas | 199 MW | 1958 |
| Marshalltown | Iowa | Natural gas | 189 MW | 1978 |
| English Farms | Iowa | Wind | 172 MW | 2019 |
| Pleasant Creek Unit 2 | Iowa | Solar | 150 MW | 2024 |
| Wever Solar (150MW) | Iowa | Solar | 150 MW | 2024 |
| Richland (IA) | Iowa | Wind | 131 MW | 2020 |
| Franklin County Wind Farm | Iowa | Wind | 99 MW | 2012 |
| Lime Creek | Iowa | Oil and petroleum | 90.2 MW | 1991 |
| Creston Solar (50 MW) | Iowa | Solar | 50 MW | 2024 |
| Pleasant Creek Unit 1 | Iowa | Solar | 50 MW | 2024 |
| Deer Run Battery | Iowa | Battery storage | 5 MW | 2023 |
| Grinnell Customer Hosted Solar | Iowa | Solar | 5 MW | 2025 |
| Cedar Rapids Community Solar | Iowa | Solar | 4.5 MW | 2024 |
| West Dubuque Solar | Iowa | Solar | 3.8 MW | 2017 |
| Decorah Battery | Iowa | Battery storage | 2.5 MW | 2021 |
| Hy-Vee Customer Hosted 2.25MW Solar | Iowa | Solar | 2.3 MW | 2024 |
| Creston School Customer Hosted Solar | Iowa | Solar | 1.4 MW | 2025 |
| ISU Customer Hosted 1MW Solar Project | Iowa | Solar | 1.4 MW | 2024 |
| Clinton Schools | Iowa | Solar | 1.3 MW | 2025 |
| Fareway Customer Hosted 1 MW Solar | Iowa | Solar | 1 MW | 2024 |
| Perry Customer Hosted 1MW Solar Project | Iowa | Solar | 1 MW | 2024 |