Coso Energy Developers
Inyo County, California · EIA plant ID 10875 · Operator: Coso Operating Co LLC
Nameplate90MWSummer 68 MW
Generators3in service
Net generation235GWh12 mo to Dec 2025
Capacity factor40%geothermal units, summer MW
Heat rate—thermal plants only
First online1988
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), geothermal 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 | 769.3 | 110.1% | — |
| 2002 | 727.1 | 104.0% | — |
| 2003 | 638.2 | 104.8% | — |
| 2004 | 607.4 | 99.5% | — |
| 2005 | 589.7 | 96.9% | — |
| 2006 | 558.2 | 91.7% | — |
| 2007 | 494.3 | 83.2% | — |
| 2008 | 486.6 | 81.7% | — |
| 2009 | 507.3 | 85.4% | — |
| 2010 | 469.3 | 79.0% | — |
| 2011 | 405.9 | 68.3% | — |
| 2012 | 358.8 | 60.3% | — |
| 2013 | 373.2 | 62.8% | — |
| 2014 | 341 | 57.4% | — |
| 2015 | 295.6 | 49.8% | — |
| 2016 | 267.2 | 44.9% | — |
| 2017 | 271.7 | 45.8% | — |
| 2018 | 284.8 | 47.9% | — |
| 2019 | 279 | 47.0% | — |
| 2020 | 267.4 | 44.9% | — |
| 2021 | 308.1 | 51.9% | — |
| 2022 | 285.4 | 48.1% | — |
| 2023 | 277.3 | 46.7% | — |
| 2024 | 244.2 | 41.0% | — |
| 2025 | 235 | 39.6% | — |
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 |
|---|---|---|---|---|---|---|---|---|
| GEN7 | Geothermal | ST | 30 | 21.8 | Dec 1988 | Operating | — | coming soon |
| GEN8 | Geothermal | ST | 30 | 22.5 | Dec 1988 | Operating | — | coming soon |
| GEN9 | Geothermal | ST | 30 | 23.5 | Aug 1989 | Operating | — | coming soon |
Owner / operator
Operator: Coso Operating Co LLC. Ownership shares by in-service nameplate MW (EIA-860 Schedule 4; units not listed there are wholly owned by the operator).
| Coso Operating Co LLC | 100.0% | 90 MW |
Nearby plants
Within 80 km.
| Coso Power Developers | 90 MW | 1.9 km |
| Coso Battery Storage | 60 MW | 2.1 km |
| Mordor ES1 | 25 MW | 2.4 km |
| Mordor ES2 | 20 MW | 2.5 km |
| Coso Finance Partners | 92 MW | 4 km |
| Haiwee | 6 MW | 19.3 km |