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Mammoth G2

Other power plant · Mono County, California

Nameplate capacity
15 MW
Rank in California
#758
of 1,897 plants
In service since
1990
December 1990

Details

Primary fuel
Other
Technology
Geothermal
Operator
Ormat Nevada Inc
County
Mono County
Generating units
3
Share of state capacity
0.01%
Rank among other plants in California
#62 of 152
EIA plant code
10481

Generating units

Individual generating units at Mammoth G2
UnitTechnologyNameplateSummerOnlineStatus
1Geothermal5.0 MW3.3 MW1990Operating
2Geothermal5.0 MW3.3 MW1990Operating
3Geothermal5.0 MW3.3 MW1990Operating

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 California

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 15 MW solar plant and a 15 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 California power plants · What California actually generates