Electric utility · EIA utility id 9417
Interstate Power and Light Co
- Ownership, as EIA reports it
- Investor Owned
- States served
- IA
- Customers in 2025
- 506,498
- Sales in 2025
- 13,913,310 MWh
- Revenue in 2025
- $1,813,200,000
U.S. Energy Information Administration · Annual Electric Power Industry Report (Form EIA-861) · data for 2025 · as of Oct 7, 2026 · retrieved Oct 31, 2026 · CC-BY-4.0 May be out of date. The next release was due by Oct 7, 2027. Last checked for an update: Oct 31, 2026.
What it sells and charges
Full service (energy and delivery)
| Sector | Customers | Sales (MWh) | Revenue | Average price (cents per kWh) |
|---|---|---|---|---|
| Residential | 419,451 | 3,721,680 | $661,272,000 | 17.77 |
| Commercial | 85,846 | 4,127,001 | $621,320,000 | 15.05 |
| Industrial | 1,201 | 6,064,629 | $530,608,000 | 8.75 |
Its average price is 30% above the state average for residential customers (13.62 cents per kWh in IA).
How we got this
$661,272,000 residential revenue ÷ 3,721,680,000 kWh residential sales = 17.77 cents per kWh
Average price is revenue divided by sales, for full-service customers only. It averages every rate and every month, so one household's price can differ. State averages count revenue from every kind of service and sales only once, as EIA does.
Trends, 2021 to 2025
Trend table
| Year | Residential average price (cents per kWh) | Customers |
|---|---|---|
| 2021 | 16.84 | 497,289 |
| 2022 | 17.75 | 499,378 |
| 2023 | 17.86 | 501,812 |
| 2024 | 17.90 | 504,146 |
| 2025 | 17.77 | 506,498 |
U.S. Energy Information Administration · Annual Electric Power Industry Report (Form EIA-861), 2021 to 2025 · data for 2021-2025 · as of Oct 7, 2026 · retrieved Oct 31, 2026 · CC-BY-4.0 May be out of date. The next release was due by Oct 7, 2027. Last checked for an update: Oct 31, 2026.
Annual peak demand
Not reported to FERC. Only utilities that plan or balance their own system file Form 714.
Its balancing authority, MISO, peaked at 121,059 MW in 2025. That is the balancing authority's peak, not this utility's.
Catalyst Cooperative (PUDL), from FERC Form 714 · Annual peak demand by planning area (FERC Form 714, through PUDL) · data for 2006-2025 · as of Oct 14, 2026 · retrieved Oct 31, 2026 · CC-BY-4.0 May be out of date. The next release was due by Jan 14, 2027. Last checked for an update: Oct 31, 2026.
Reliability
| State | Standard | SAIDI with major events (minutes) | SAIFI with major events | SAIDI without major events (minutes) | SAIFI without major events |
|---|---|---|---|---|---|
| IA | The utility's own | 88.5 | 0.82 | 73.99 | 0.76 |
SAIDI is the average minutes without power per customer in the year; SAIFI is how many outages the average customer had. Major event days are storms and similar rare days, counted with and without.
Generation it operates
| Fuel | Capacity | Net generation in 2025 |
|---|---|---|
| Natural gas | 1,937.3 MW | 5,698,691 MWh |
| Wind | 1,301.5 MW | 4,299,256 MWh |
| Subbituminous coal | 775.9 MW | 2,901,694 MWh |
| Solar | 424.3 MW | 758,703 MWh |
| Distillate fuel oil | 90.2 MW | -4,655 MWh |
| Batteries | 7.8 MW | -537 MWh |
This is generation the utility operates, not the full mix of power it buys. EIA does not publish that mix for each utility.
Plants it operates
- Marshalltown · IA · 189 MW
- Prairie Creek · IA · 198.8 MW
- Burlington (IA) · IA · 290.8 MW
- Ottumwa · IA · 725.9 MW
- Lime Creek · IA · 90.2 MW
- Emery Station · IA · 602.8 MW
- Whispering Willow Wind Farm - East · IA · 199.7 MW
- Franklin County Wind Farm · IA · 99 MW
- Marshalltown Generating Station · IA · 708.8 MW
- West Dubuque Solar · IA · 3.8 MW
- Upland Prairie · IA · 299.3 MW
- English Farms · IA · 171.5 MW
- Whispering Willow North · IA · 201.3 MW
- Richland (IA) · IA · 130.9 MW
- Golden Plains · IA · 199.8 MW
- Decorah Battery · IA · 2.5 MW
- Deer Run Battery · IA · 5 MW
- Cedar Rapids Community Solar · IA · 4.5 MW
- Fareway Customer Hosted 1 MW Solar · IA · 1 MW
- Hy-Vee Customer Hosted 2.25MW Solar · IA · 2.3 MW
- ISU Customer Hosted 1MW Solar Project · IA · 1.4 MW
- Perry Customer Hosted 1MW Solar Project · IA · 1 MW
- Pleasant Creek Unit 1 · IA · 50 MW
- Creston Solar (50 MW) · IA · 50 MW
- Pleasant Creek Unit 2 · IA · 150 MW
- Wever Solar (150MW) · IA · 150 MW
- Creston School Customer Hosted Solar · IA · 1.4 MW
- Grinnell Customer Hosted Solar · IA · 5 MW
- Clinton Schools · IA · 1.3 MW
Published rates
35 rates in the OpenEI database, newest updated Jul 23, 2025.
OpenEI (National Laboratory of the Rockies), with rates entered by contributors · U.S. Utility Rate Database (OpenEI) · data for 2026-10 · as of Oct 30, 2026 · retrieved Oct 31, 2026 · CC-BY-4.0 May be out of date. The next release was due by Nov 30, 2026. Last checked for an update: Oct 31, 2026.