128th largest plant in Washington · 10066th nationally
Twin Reservoirs is a hydroelectric power plant in Washington with a nameplate capacity of 2.2 MW. It generates roughly 8.1k MWh per year — enough to power about 775 average U.S. homes.
Its capacity factor of 42% puts it in the middle range — running steadily but not full-time.
| Plant Name | Twin Reservoirs |
|---|---|
| Operator | Walla Walla City Of |
| City | Walla Walla |
| County | Walla Walla County |
| State | Washington |
| ZIP | 99362 |
| Coordinates | 46.08833, -118.25472 |
This plant highlighted in navy-ringed pin; other generators within 25 miles shown as fuel-colored dots.
| ID | Technology | Fuel | Capacity | Status | Online |
|---|---|---|---|---|---|
| GEN1 | Conventional Hydroelectric | Water | 2.2 MW | Operating | 1988 |
| NERC Region | WECC |
|---|---|
| Balancing Authority | Bonneville Power Administration |
Hydroelectric plants spin turbines using falling or flowing water — typically from a dam-impounded reservoir. They are dispatchable, long-lived, and emission-free at the point of generation, though large reservoirs can disrupt rivers and ecosystems and methane can be released from flooded vegetation.