Yellowtail
Big Horn County, Montana · EIA plant ID 2204 · Operator: U S Bureau of Reclamation
Nameplate278MWSummer 288 MW
Generators4in service
Net generation566GWh12 mo to Dec 2025
Capacity factor22%hydro units, summer MW
Heat rate—thermal plants only
First online1966
Monthly net generation
EIA-923, all units at the plant. Net of station use; storage can go negative.
FinalPreliminary
Capacity factor by year
Net MWh ÷ (summer MW × hours), hydro units. Each year uses that year's EIA-860 ratings; the hollow dot is the latest 12 months.
Heat rate by year
Electric fuel MMBtu × 1000 ÷ net MWh (Btu/kWh, HHV), fossil units only; CT + CA counted as one combined-cycle block.
Heat rate applies to fuel-burning (thermal) units only.
Annual data table
| Year | Net GWh | Capacity factor | Heat rate (Btu/kWh) |
|---|---|---|---|
| 2001 | 474.2 | 18.9% | — |
| 2002 | 344.4 | 13.7% | — |
| 2003 | 325.3 | 12.9% | — |
| 2004 | 321 | 12.7% | — |
| 2005 | 603.8 | 24.0% | — |
| 2006 | 475.2 | 18.9% | — |
| 2007 | 380.4 | 15.1% | — |
| 2008 | 769.3 | 30.5% | — |
| 2009 | 898.5 | 35.7% | — |
| 2010 | 830.7 | 33.0% | — |
| 2011 | 1,124 | 44.7% | — |
| 2012 | 527.7 | 20.9% | — |
| 2013 | 471 | 18.7% | — |
| 2014 | 1,095.9 | 43.6% | — |
| 2015 | 744.1 | 29.6% | — |
| 2016 | 690.3 | 30.3% | — |
| 2017 | 1,124.3 | 49.5% | — |
| 2018 | 1,059 | 45.0% | — |
| 2019 | 914 | 37.5% | — |
| 2020 | 780.4 | 31.9% | — |
| 2021 | 512.2 | 20.3% | — |
| 2022 | 685.9 | 27.2% | — |
| 2023 | 846 | 33.6% | — |
| 2024 | 798.4 | 31.6% | — |
| 2025 | 566.2 | 22.5% | — |
Generators
EIA-860 (annual) with EIA-860M updates through Sep 2026. EIA-923 reports generation by plant, prime mover and fuel, not by unit, so unit-level output isn't shown.
| Gen ID | Technology | Prime mover | Nameplate MW | Summer MW | Online | Status | Planned retirement | OEM / model |
|---|---|---|---|---|---|---|---|---|
| 1 | Conventional Hydroelectric | HY | 71.9 | 71.9 | Nov 1966 | Operating | — | coming soon |
| 2 | Conventional Hydroelectric | HY | 62.5 | 71.9 | Oct 1966 | Operating | — | coming soon |
| 3 | Conventional Hydroelectric | HY | 71.9 | 71.9 | Aug 1966 | Operating | — | coming soon |
| 4 | Conventional Hydroelectric | HY | 71.9 | 71.8 | Aug 1966 | Operating | — | coming soon |
Owner / operator
Operator: U S Bureau of Reclamation. Ownership shares by in-service nameplate MW (EIA-860 Schedule 4; units not listed there are wholly owned by the operator).
| U S Bureau of Reclamation | 100.0% | 278 MW |
Nearby plants
Within 80 km.
| South Mills Solar, LLC | 3 MW | 53.4 km |
| Hardin Generator Project | 116 MW | 57.3 km |
| Pryor Mountain Wind | 240 MW | 59.7 km |
| Western Sugar Cooperative - Billings | 2 MW | 66.1 km |
| Phillips 66 Billings Refinery | 2 MW | 66.7 km |
| Yellowstone Energy LP | 68 MW | 67 km |