Power plants in the California ISO balancing area
The California ISO balancing area takes in 1,637 power plants with 94.4 GW of nameplate capacity, the fifth-largest of the 40 areas covered here. Its plants sit in three states, with California holding 95% of the capacity. Natural gas makes up 34% of the mix, and the largest plant is Diablo Canyon (2,323 MW). Since 2020, 30.4 GW has come online here, 51% of it battery storage.
- Natural gas32,255 MW34%
- Solar24,943 MW26%
- Battery storage15,760 MW17%
- Hydroelectric6,740 MW7.1%
- Wind6,344 MW6.7%
- Nuclear2,323 MW2.5%
- Geothermal2,218 MW2.4%
- Pumped-storage hydro2,078 MW2.2%
- Biomass and waste1,007 MW1.1%
- Oil and petroleum442 MW0.5%
- Other sources186 MW0.2%
- Coal62.5 MW0.1%
Capacity by decade it came online
NuclearCoalNatural gasOil and petroleumHydroelectricPumped-storage hydroWindSolarBattery storageGeothermalBiomass and wasteOther sources
Above the line: capacity operating in 2025. Below: capacity retired at plants that still run.
The 25 largest plants in the area
| Rank | Plant | State | Runs on | Capacity | First unit |
|---|---|---|---|---|---|
| 1 | Diablo Canyon | California | Nuclear | 2,323 MW | 1985 |
| 2 | Dynegy Moss Landing Power Plant Hybrid | California | Natural gas | 1,848 MW | 2002 |
| 3 | Ormond Beach | California | Natural gas | 1,612 MW | 1971 |
| 4 | Geysers Unit 5-20 | California | Geothermal | 1,236 MW | 1971 |
| 5 | La Paloma Generating Plant | California | Natural gas | 1,156 MW | 2003 |
| 6 | AES Alamitos LLC | California | Natural gas | 1,115 MW | 1961 |
| 7 | Helms Pumped Storage | California | Pumped-storage hydro | 1,053 MW | 1984 |
| 8 | Mountainview Generating Station | California | Natural gas | 1,037 MW | 2005 |
| 9 | Bellefield Solar and Energy Storage Farm | California | Battery storage | 1,000 MW | 2025 |
| 10 | High Desert Power Plant | California | Natural gas | 960 MW | 2003 |
| 11 | Delta Energy Center | California | Natural gas | 944 MW | 2002 |
| 12 | Marsh Landing Generating Station | California | Natural gas | 828 MW | 2013 |
| 13 | Sentinel Energy Center, LLC | California | Natural gas | 800 MW | 2013 |
| 14 | Pastoria Energy Facility, LLC | California | Natural gas | 779 MW | 2005 |
| 15 | Colusa Generating Station | California | Natural gas | 712 MW | 2010 |
| 16 | Otay Mesa Generating Project | California | Natural gas | 711 MW | 2009 |
| 17 | AES Huntington Beach Energy Project | California | Natural gas | 699 MW | 2020 |
| 18 | Sunrise Power LLC | California | Natural gas | 685 MW | 2001 |
| 19 | Menifee Power Bank | California | Battery storage | 680 MW | 2024 |
| 20 | Los Medanos Energy Center | California | Natural gas | 678 MW | 2001 |
| 21 | AES Alamitos Energy Center | California | Natural gas | 678 MW | 2020 |
| 22 | Carlsbad Energy Center | California | Natural gas | 659 MW | 2018 |
| 23 | Russell City Energy Center | California | Natural gas | 655 MW | 2013 |
| 24 | Edward C Hyatt | California | Hydroelectric | 644 MW | 1968 |
| 25 | Metcalf Energy Center | California | Natural gas | 635 MW | 2005 |
States
| State | Plants | Capacity |
|---|---|---|
| California | 1,614 | 89.9 GW |
| Arizona | 13 | 2,704 MW |
| Nevada | 10 | 1,756 MW |
Operators with the most capacity
| Operator | Plants | Capacity |
|---|---|---|
| Pacific Gas & Electric Co. | 71 | 7,799 MW |
| Southern California Edison Co | 41 | 2,827 MW |
| RWE Clean Energy | 30 | 2,220 MW |
| AES Clean Energy | 9 | 2,146 MW |
| Dynegy -Moss Landing LLC | 1 | 1,848 MW |
| Ormond Beach Power, LLC | 1 | 1,612 MW |
| Terra-Gen Operating Co-Hybrid | 10 | 1,607 MW |
| California Dept. of Water Resources | 8 | 1,589 MW |
| Geysers Power Co LLC | 4 | 1,515 MW |
| MN8 Energy LLC | 49 | 1,484 MW |