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Waterloo

Natural gas power plant · Monroe County, Illinois

Nameplate capacity
38 MW
Rank in Illinois
#134
of 580 plants
In service since
1946
June 1946

Details

Primary fuel
Natural gas
Technology
Natural Gas Fired Combustion Turbine
Operator
City of Waterloo - (IL)
County
Monroe County
Generating units
14
Share of state capacity
0.07%
Rank among natural gas plants in Illinois
#40 of 72
EIA plant code
971

Generating units

Individual generating units at Waterloo
UnitTechnologyNameplateSummerOnlineStatus
14Natural Gas Fired Combustion Turbine8.0 MW7.5 MW2026Operating
13Natural Gas Fired Combustion Turbine7.0 MW6.6 MW2012Operating
12Natural Gas Fired Combustion Turbine6.6 MW6.6 MW2002Operating
1Petroleum Liquids3.1 MW2.7 MW1970Standby/Backup: available for service but not normally used
8Petroleum Liquids3.0 MW2.4 MW1973Standby/Backup: available for service but not normally used
4Petroleum Liquids2.0 MW1.8 MW1963Standby/Backup: available for service but not normally used
10Petroleum Liquids1.8 MW1.8 MW1996Operating
11Petroleum Liquids1.8 MW1.8 MW1996Operating
9Petroleum Liquids1.8 MW1.8 MW1996Operating
7Petroleum Liquids1.7 MW1.5 MW1959Standby/Backup: available for service but not normally used
5Petroleum Liquids0.5 MW0.4 MW1950Out of service and NOT expected to return to service in next calendar year
6Petroleum Liquids0.5 MW0.5 MW1950Out of service and NOT expected to return to service in next calendar year
2Petroleum Liquids0.2 MW0.2 MW1954Out of service and NOT expected to return to service in next calendar year
3Petroleum Liquids0.2 MW0.2 MW1946Out of service and NOT expected to return to service in next calendar year

Nameplate is the maximum rated output; summer capacity is what the unit can reliably deliver on a hot day, which is typically lower.

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About this data

From EIA’s inventory of operable generators, May 2026 release. Capacity is nameplate — the maximum rated output of the equipment, not what the plant actually generates over a year, which depends on how often it runs. A 38 MW solar plant and a 38 MW nuclear plant have the same entry here and produce very different amounts of electricity.

“In service since” is the earliest in-service date among the units still listed, so a site rebuilt around newer equipment can read as younger than the site itself. All Illinois power plants · What Illinois actually generates