Tulloch
Tuolumne County, California · EIA plant ID 416 · Operator: Oakdale&South San Joaquin Irrigation D.
Nameplate30MWSummer 26 MW
Generators3in service
Net generation103GWh12 mo to Dec 2025
Capacity factor46%hydro units, summer MW
Heat rate—thermal plants only
First online1958
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 | 91.8 | 58.2% | — |
| 2002 | 97.3 | 61.7% | — |
| 2003 | 94 | 59.6% | — |
| 2004 | 89.3 | 56.5% | — |
| 2005 | 90.4 | 57.3% | — |
| 2006 | 138.7 | 88.0% | — |
| 2007 | 108.9 | 69.0% | — |
| 2008 | 93.3 | 59.0% | — |
| 2009 | 95.4 | 60.5% | — |
| 2010 | 95.6 | 60.7% | — |
| 2011 | 105.7 | 67.0% | — |
| 2012 | 114 | 52.6% | — |
| 2013 | 106.8 | 47.3% | — |
| 2014 | 91.5 | 40.5% | — |
| 2015 | 69.3 | 30.7% | — |
| 2016 | 85.6 | 37.8% | — |
| 2017 | 140.4 | 62.1% | — |
| 2018 | 112.9 | 50.0% | — |
| 2019 | 146.3 | 65.5% | — |
| 2020 | 115.3 | 51.5% | — |
| 2021 | 110.1 | 49.3% | — |
| 2022 | 98.4 | 44.0% | — |
| 2023 | 124.9 | 55.9% | — |
| 2024 | 103.6 | 46.3% | — |
| 2025 | 103.2 | 46.2% | — |
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 | 11.7 | 9 | Jun 1958 | Operating | — | coming soon |
| 2 | Conventional Hydroelectric | HY | 11.7 | 10 | Jun 1958 | Operating | — | coming soon |
| 3 | Conventional Hydroelectric | HY | 6.5 | 6.5 | Mar 2012 | Operating | — | coming soon |
Owner / operator
Operator: Oakdale&South San Joaquin Irrigation D.. Ownership shares by in-service nameplate MW (EIA-860 Schedule 4; units not listed there are wholly owned by the operator).
| Oakdale&South San Joaquin Irrigation D. | 100.0% | 30 MW |
Nearby plants
Within 80 km.
| Sonora 1 | 2 MW | 6.9 km |
| New Melones | 300 MW | 10.4 km |
| Pacific-Ultrapower Chinese Station | 25 MW | 11.2 km |
| Sierra Energy Storage, LLC | 10 MW | 11.2 km |
| Sierra Pacific Chinese Camp | 4 MW | 13.2 km |
| Frankenheimer Power Plant | 5 MW | 18.4 km |