Twin Falls (ID)
Twin Falls County, Idaho · EIA plant ID 821 · Operator: Idaho Power Co
Nameplate53MWSummer 52 MW
Generators2in service
Net generation44GWh12 mo to Dec 2025
Capacity factor5%hydro units, summer MW
Heat rate—thermal plants only
First online1935
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 | 52.9 | 11.2% | — |
| 2002 | 43.1 | 9.1% | — |
| 2003 | 35.9 | 7.5% | — |
| 2004 | 33.4 | 7.0% | — |
| 2005 | 54.4 | 11.5% | — |
| 2006 | 150.3 | 31.6% | — |
| 2007 | 87.6 | 18.4% | — |
| 2008 | 74 | 15.5% | — |
| 2009 | 171.7 | 36.8% | — |
| 2010 | 115.4 | 24.8% | — |
| 2011 | 394.5 | 84.7% | — |
| 2012 | 166.4 | 35.6% | — |
| 2013 | 55.4 | 11.9% | — |
| 2014 | 59.8 | 12.8% | — |
| 2015 | 76.1 | 16.3% | — |
| 2016 | 39.4 | 8.4% | — |
| 2017 | 214.3 | 46.0% | — |
| 2018 | 262 | 56.2% | — |
| 2019 | 147.6 | 31.7% | — |
| 2020 | 53.2 | 11.4% | — |
| 2021 | 43.1 | 11.7% | — |
| 2022 | 22.4 | 5.1% | — |
| 2023 | 37.1 | 9.6% | — |
| 2024 | 101 | 21.9% | — |
| 2025 | 43.5 | 9.5% | — |
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 | 8.4 | 10.1 | Mar 1935 | Operating | — | coming soon |
| 2 | Conventional Hydroelectric | HY | 44.3 | 42.2 | Jul 1995 | Operating | — | coming soon |
| P1 | Conventional Hydroelectric | HY | 44.3 | 44.3 | Jul 1995 | not_current | — | coming soon |
Owner / operator
Operator: Idaho Power Co. Ownership shares by in-service nameplate MW (EIA-860 Schedule 4; units not listed there are wholly owned by the operator).
| Idaho Power Co | 100.0% | 53 MW |
Nearby plants
Within 80 km.
| Shoshone Falls | 15 MW | 4 km |
| Clif Bar Bakery of Twin Falls | 2 MW | 7.1 km |
| Amalgamated Sugar Twin Falls | 13 MW | 8.9 km |
| South Forks Hydro | 8 MW | 11.2 km |
| Crystal Springs | 2 MW | 12.5 km |
| Low Line Rapids | 3 MW | 12.6 km |