Ripon Mill
San Joaquin County, California · EIA plant ID 50299 · Operator: AltaGas Ripon Energy Inc.
Nameplate50MWSummer 46 MW
Generators1in service
Net generation2GWh12 mo to Aug 2026
Capacity factor0%gas/coal/oil units, summer MW
Heat rate11,001Btu/kWhfossil units, electric fuel, HHV
First online1988Runs as rarely runs
The 12-month figures include preliminary EIA-923 months, which EIA revises. Final data runs through Dec 2025.
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), gas/coal/oil 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.
Annual data table
| Year | Net GWh | Capacity factor | Heat rate (Btu/kWh) |
|---|---|---|---|
| 2001 | 324.4 | 79.6% | 8,663 |
| 2002 | 340.9 | 83.7% | 8,435 |
| 2003 | 380.2 | 93.3% | 8,788 |
| 2004 | 333.9 | 81.8% | 8,090 |
| 2005 | 281.9 | 69.2% | 8,090 |
| 2006 | 245.5 | 60.3% | 8,090 |
| 2007 | 272.7 | 66.9% | 8,054 |
| 2008 | 299.4 | 73.3% | 8,424 |
| 2009 | 243.2 | 59.7% | 8,012 |
| 2010 | 132.3 | 32.5% | 8,347 |
| 2011 | 118.6 | 29.1% | 8,389 |
| 2012 | 129.1 | 31.6% | 8,303 |
| 2013 | 116.8 | 28.7% | 8,289 |
| 2014 | 112.8 | 27.7% | 8,329 |
| 2015 | 46.7 | 11.6% | 8,271 |
| 2016 | 10.9 | 2.7% | 9,983 |
| 2017 | 19.3 | 4.8% | 9,980 |
| 2018 | 9.9 | 2.4% | 10,092 |
| 2019 | 5.4 | 1.3% | 10,375 |
| 2020 | 6.9 | 1.7% | 10,333 |
| 2021 | 4.3 | 1.1% | 10,361 |
| 2022 | 3.9 | 1.0% | 9,647 |
| 2023 | 3.1 | 0.8% | 10,558 |
| 2024 | 2.2 | 0.5% | 10,910 |
| 2025 | 0.9 | 0.2% | 10,220 |
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 |
|---|---|---|---|---|---|---|---|---|
| GEN1 | Natural Gas Fired Combustion Turbine | GT | 49.5 | 46.1 | Apr 1988 | Operating | — | coming soon |
Owner / operator
Operator: AltaGas Ripon Energy Inc.. Ownership shares by in-service nameplate MW (EIA-860 Schedule 4; units not listed there are wholly owned by the operator).
| AltaGas Ripon Energy Inc. | 100.0% | 50 MW |
Nearby plants
Within 80 km.
| Ripon Generation Station | 121 MW | 0.1 km |
| Noosa Energy Storage LLC | — | 3.9 km |
| Tesoro RV & Boat Storage | 3 MW | 7.9 km |
| CA Manteca 730 Spreckels Ave | 3 MW | 9.3 km |
| Axium Modesto Solar | 25 MW | 10.6 km |
| Aurora Renewable Energy (Hybrid) | — | 12.2 km |