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Interstate

Natural gas power plant · Sangamon County, Illinois

Nameplate capacity
139 MW
Rank in Illinois
#93
of 580 plants
In service since
1997
September 1997

Details

Primary fuel
Natural gas
Technology
Natural Gas Fired Combustion Turbine
Operator
City of Springfield - (IL)
County
Sangamon County
Generating units
1
Share of state capacity
0.26%
Rank among natural gas plants in Illinois
#33 of 72
EIA plant code
7425

Generating units

Individual generating units at Interstate
UnitTechnologyNameplateSummerOnlineStatus
1Natural Gas Fired Combustion Turbine139 MW110 MW1997Operating

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

Similarly sized plants in Illinois

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 139 MW solar plant and a 139 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