Nameplate capacity
675 MW
Rank in Idaho
#1
of 155 plants
In service since
1958
August 1958
Details
- Primary fuel
- Hydro
- Technology
- Conventional Hydroelectric
- Operator
- Idaho Power Co
- County
- Washington County
- Generating units
- 5
- Share of state capacity
- 10.27%
- Rank among hydro plants in Idaho
- #1 of 76
- EIA plant code
- 811
Generating units
| Unit | Technology | Nameplate | Summer | Online | Status |
|---|---|---|---|---|---|
| 5 | Conventional Hydroelectric | 225 MW | 218 MW | 1980 | Operating |
| 1 | Conventional Hydroelectric | 113 MW | 127 MW | 1959 | Operating |
| 2 | Conventional Hydroelectric | 113 MW | 109 MW | 1958 | Operating |
| 3 | Conventional Hydroelectric | 113 MW | 125 MW | 1958 | Operating |
| 4 | Conventional Hydroelectric | 113 MW | 124 MW | 1958 | 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 Idaho
| Dworshak | Hydro | 465 MW |
| Langley Gulch Power Plant | Natural gas | 319 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 675 MW solar plant and a 675 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 Idaho power plants · What Idaho actually generates