Hermiston Power Partnership
Natural gas power plant · Umatilla County, Oregon
Nameplate capacity
689 MW
Rank in Oregon
#5
of 301 plants
In service since
2002
August 2002
Details
- Primary fuel
- Natural gas
- Technology
- Natural Gas Fired Combined Cycle
- Operator
- Hermiston Power Partnership
- County
- Umatilla County
- Generating units
- 3
- Share of state capacity
- 3.59%
- Rank among natural gas plants in Oregon
- #1 of 12
- EIA plant code
- 55328
Generating units
| Unit | Technology | Nameplate | Summer | Online | Status |
|---|---|---|---|---|---|
| STG1 | Natural Gas Fired Combined Cycle | 264 MW | 235 MW | 2002 | Operating |
| CTG1 | Natural Gas Fired Combined Cycle | 213 MW | 197 MW | 2002 | Operating |
| CTG2 | Natural Gas Fired Combined Cycle | 213 MW | 197 MW | 2002 | 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 Oregon
| Bonneville | Hydro | 1,162 MW |
| McNary | Hydro | 991 MW |
| Hermiston Generating Plant | Natural gas | 621 MW |
| Beaver | Natural gas | 611 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 689 MW solar plant and a 689 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 Oregon power plants · What Oregon actually generates