315th largest plant in California · 2915th nationally
Sonoma California Geothermal is a geothermal power plant in California with a nameplate capacity of 78.0 MW. It generates roughly 431.5k MWh per year — enough to power about 41,098 average U.S. homes.
Its capacity factor of 63% puts it in the middle range — running steadily but not full-time. At 89 lb CO₂/MWh, its emission rate sits below the national grid average of roughly 800 lb/MWh.
| Plant Name | Sonoma California Geothermal |
|---|---|
| Operator | Geysers Power Co Llc |
| City | Middletown |
| County | Lake County |
| State | California |
| ZIP | 95461 |
| Coordinates | 38.79030, -122.75590 |
This plant highlighted in navy-ringed pin; other generators within 25 miles shown as fuel-colored dots.
| ID | Technology | Fuel | Capacity | Status | Online |
|---|---|---|---|---|---|
| 1 | Geothermal | Geothermal | 78.0 MW | Operating | 1983 |
| CO₂ | 19.2k metric tons |
|---|---|
| CO₂ Rate | 89 lb/MWh |
Annual totals and CO₂ rate reported by EPA eGRID for 2023. Reference averages are approximate U.S.-wide figures from the same dataset.
| NERC Region | WECC |
|---|---|
| Balancing Authority | California Independent System Operator |
Geothermal plants tap heat from underground reservoirs to spin steam turbines. They provide carbon-free baseload power with very high capacity factors, but they only work where hot rock is accessible — primarily in the western U.S.