6th largest plant in Oregon · 588th nationally
Hermiston Generating Plant is a natural gas power plant in Oregon with a nameplate capacity of 621 MW. It generates roughly 3.0M MWh per year — enough to power about 284,718 average U.S. homes.
Its capacity factor of 55% puts it in the middle range — running steadily but not full-time. At 876 lb CO₂/MWh, its emission rate sits above the national grid average of roughly 800 lb/MWh.
Ghost bars are each month's theoretical maximum (621 MW nameplate × hours in the month). Filled bars are actual net generation reported to EIA Form 923. The gap between them is capacity factor made visible.
| Plant Name | Hermiston Generating Plant |
|---|---|
| Operator | Hermiston Generating Co Lp |
| City | Hermiston |
| County | Umatilla County |
| State | Oregon |
| ZIP | 97838 |
| Coordinates | 45.80420, -119.37000 |
This plant highlighted in navy-ringed pin; other generators within 25 miles shown as fuel-colored dots.
| ID | Technology | Fuel | Capacity | Status | Online |
|---|---|---|---|---|---|
| GEN2 | Natural Gas Fired Combined Cycle | Natural Gas | 205 MW | Operating | 1996 |
| GEN4 | Natural Gas Fired Combined Cycle | Natural Gas | 205 MW | Operating | 1996 |
| GEN1 | Natural Gas Fired Combined Cycle | Natural Gas | 106 MW | Operating | 1996 |
| GEN3 | Natural Gas Fired Combined Cycle | Natural Gas | 106 MW | Operating | 1996 |
| Owner | Location | Share |
|---|---|---|
| Hermiston Generating Co Lp | Hermiston, OR | 5000.0% |
| Pacificorp | Portland, OR | 5000.0% |
Ownership reported to EIA Form 860. Percentages reflect reported generator-level ownership share, averaged when a plant has multiple generators.
| CO₂ | 1.3M metric tons |
|---|---|
| SO₂ | 7 metric tons |
| NOₓ | 156 metric tons |
| CO₂ Rate | 876 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 | Pacificorp - West |
Natural gas plants are the workhorse of the modern grid. Combined-cycle units achieve very high efficiency and can ramp up and down quickly to balance variable renewables. They emit roughly half the CO₂ per MWh of coal and far less of other pollutants, but they still release upstream methane during fuel extraction.