Sonoma California Geothermal
Other power plant · Lake County, California
Nameplate capacity
78 MW
Rank in California
#333
of 1,897 plants
In service since
1983
December 1983
Details
- Primary fuel
- Other
- Technology
- Geothermal
- Operator
- Geysers Power Co LLC
- County
- Lake County
- Generating units
- 1
- Share of state capacity
- 0.07%
- Rank among other plants in California
- #13 of 152
- EIA plant code
- 510
Generating units
| Unit | Technology | Nameplate | Summer | Online | Status |
|---|---|---|---|---|---|
| 1 | Geothermal | 78 MW | 50 MW | 1983 | Operating |
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
| Montezuma Wind II | Wind | 78 MW |
| Vasco Winds | Wind | 78 MW |
| Arrowleaf Solar and Storage | Solar | 77 MW |
| McClellan (CA) | Natural gas | 77 MW |
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 78 MW solar plant and a 78 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