In Madison County, Iowa (IA). The map on this page is placed at the coordinates EIA files for the plant, which locate the site rather than any individual unit.

How big is Winterset?

18 MW of nameplate capacity across 8 units, as of the EIA-860M release for 2026-07.

EIA-860M names City of Winterset - (IA) as the reporting entity. That is the operator of record on the survey, which is not always the ultimate owner.

Is this the same as Winterset LLC?

Probably, but EIA-860M does not say. The survey records a plant name and a reporting entity — City of Winterset - (IA) here — not the project company that holds the asset. Project companies are commonly registered as an LLC carrying the plant's name, so a search for "Winterset LLC" usually means this site. This page shows only what EIA files, and does not assert a corporate structure it cannot see.

Is Winterset still running?

EIA-860M files it as "Operating" for 2026-07. Statuses change monthly, and this page follows the monthly release.

Winterset

Winterset is a 18 MW oil-fired power plant in Madison County, Iowa, operated by City of Winterset - (IA). EIA-860M lists 8 generating units here, inside MISO. Its units entered service between 1956 and 2022.

As of 2026-07 (inventory dated 2026-07-31) · EIA-860M Preliminary Monthly Electric Generator Inventory · eia.gov/…/july_generator2026.xlsx · eia.gov/…/eia860m

Nameplate capacity: 17.6 MW; 17.6 MW net summer
Generating units: 8
In service: 1956–2022
EIA plant ID: 1203

Where it is

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County: Madison County, Iowa
Coordinates: 41.3372, -94.0126
Balancing authority: MISO
Sector: Electric Utility

Units, technology and status

Operator of record: City of Winterset - (IA)
Primary energy source: Petroleum
Technologies: Natural Gas Internal Combustion Engine, Petroleum Liquids
Status: Operating

This site runs on more than one energy source. EIA-860M capacity splits: Petroleum 10 MW, Natural gas 8 MW. It is filed here under Petroleum, the source with the most capacity.

Every plant City of Winterset - (IA) reports to EIA →

Winterset: FAQ

Where is Winterset?: In Madison County, Iowa (IA). The map on this page is placed at the coordinates EIA files for the plant, which locate the site rather than any individual unit.
How big is Winterset?: 18 MW of nameplate capacity across 8 units, as of the EIA-860M release for 2026-07.
Who owns Winterset?: EIA-860M names City of Winterset - (IA) as the reporting entity. That is the operator of record on the survey, which is not always the ultimate owner.
Is this the same as Winterset LLC?: Probably, but EIA-860M does not say. The survey records a plant name and a reporting entity — City of Winterset - (IA) here — not the project company that holds the asset. Project companies are commonly registered as an LLC carrying the plant's name, so a search for "Winterset LLC" usually means this site. This page shows only what EIA files, and does not assert a corporate structure it cannot see.
Is Winterset still running?: EIA-860M files it as "Operating" for 2026-07. Statuses change monthly, and this page follows the monthly release.