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

38 MW of nameplate capacity across 14 units, as of the EIA-860M release for 2026-07.

EIA-860M names City of Waterloo - (IL) 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 Waterloo LLC?

Probably, but EIA-860M does not say. The survey records a plant name and a reporting entity — City of Waterloo - (IL) 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 "Waterloo LLC" usually means this site. This page shows only what EIA files, and does not assert a corporate structure it cannot see.

Is Waterloo still running?

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

Waterloo

Waterloo is a 38 MW natural gas power plant in Monroe County, Illinois, operated by City of Waterloo - (IL). EIA-860M lists 14 generating units here, inside MISO. Its units entered service between 1946 and 2026.

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: 38.2 MW; 35.8 MW net summer
Generating units: 14
In service: 1946–2026
EIA plant ID: 971

Where it is

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County: Monroe County, Illinois
Coordinates: 38.3348, -90.1589
Balancing authority: MISO
Sector: Electric Utility

Units, technology and status

Operator of record: City of Waterloo - (IL)
Primary energy source: Natural gas
Technologies: Natural Gas Fired Combustion Turbine, Petroleum Liquids
Status: Operating (6) · Standby/Backup (4) · Out of service and NOT expected to return to service in next calendar year (4)

This site runs on more than one energy source. EIA-860M capacity splits: Natural gas 22 MW, Petroleum 17 MW. It is filed here under Natural gas, the source with the most capacity.

Every plant City of Waterloo - (IL) reports to EIA →

Waterloo: FAQ

Where is Waterloo?: In Monroe County, Illinois (IL). 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 Waterloo?: 38 MW of nameplate capacity across 14 units, as of the EIA-860M release for 2026-07.
Who owns Waterloo?: EIA-860M names City of Waterloo - (IL) 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 Waterloo LLC?: Probably, but EIA-860M does not say. The survey records a plant name and a reporting entity — City of Waterloo - (IL) 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 "Waterloo LLC" usually means this site. This page shows only what EIA files, and does not assert a corporate structure it cannot see.
Is Waterloo still running?: EIA-860M files it as "Operating" for 2026-07. Statuses change monthly, and this page follows the monthly release.