Dion R Holm
Hydro power plant · Tuolumne County, California
Nameplate capacity
180 MW
Rank in California
#145
of 1,897 plants
In service since
1960
August 1960
Details
- Primary fuel
- Hydro
- Technology
- Conventional Hydroelectric
- Operator
- City & County of San Francisco
- County
- Tuolumne County
- Generating units
- 2
- Share of state capacity
- 0.17%
- Rank among hydro plants in California
- #14 of 244
- EIA plant code
- 380
Generating units
| Unit | Technology | Nameplate | Summer | Online | Status |
|---|---|---|---|---|---|
| 1 | Conventional Hydroelectric | 90 MW | 90 MW | 1960 | Operating |
| 2 | Conventional Hydroelectric | 90 MW | 90 MW | 1960 | 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
| Redding Power | Natural gas | 183 MW |
| Elkhorn Battery Energy Storage System | Battery storage | 183 MW |
| El Segundo Cogen | Natural gas | 180 MW |
| Spring Creek | Hydro | 180 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 180 MW solar plant and a 180 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