6th largest plant in Montana · 1135th nationally
Yellowtail is a hydroelectric power plant in Montana with a nameplate capacity of 278 MW. It generates roughly 846.0k MWh per year — enough to power about 80,569 average U.S. homes.
Its capacity factor of 35% reflects intermittent or peaking operation.
| Plant Name | Yellowtail |
|---|---|
| Operator | U S Bureau Of Reclamation |
| City | Hardin |
| County | Big Horn County |
| State | Montana |
| ZIP | 59034 |
| Coordinates | 45.30741, -107.95752 |
| ID | Technology | Fuel | Capacity | Status | Online |
|---|---|---|---|---|---|
| 1 | Conventional Hydroelectric | Water | 71.9 MW | Operating | 1966 |
| 3 | Conventional Hydroelectric | Water | 71.9 MW | Operating | 1966 |
| 4 | Conventional Hydroelectric | Water | 71.9 MW | Operating | 1966 |
| 2 | Conventional Hydroelectric | Water | 62.5 MW | Operating | 1966 |
| NERC Region | WECC |
|---|---|
| Balancing Authority | Western Area Power Administration Ugp West |
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.