Castaic

Hydro power plant · Los Angeles County, California

Nameplate capacity
1,682 MW
Rank in California
#4
of 1,897 plants
In service since
1972
January 1972

Details

Primary fuel
Hydro
Technology
Hydroelectric Pumped Storage
Operator
Los Angeles Department of Water & Power
County
Los Angeles County
Generating units
7
Share of state capacity
1.56%
Rank among hydro plants in California
#1 of 244
EIA plant code
392

Generating units

Individual generating units at Castaic
UnitTechnologyNameplateSummerOnlineStatus
1Hydroelectric Pumped Storage271 MW271 MW1973Operating
2Hydroelectric Pumped Storage271 MW271 MW1974Operating
3Hydroelectric Pumped Storage271 MW271 MW1976Operating
4Hydroelectric Pumped Storage271 MW271 MW1977Operating
5Hydroelectric Pumped Storage271 MW271 MW1977Operating
6Hydroelectric Pumped Storage271 MW271 MW1978Operating
7Conventional Hydroelectric56 MW52 MW1972Operating

Nameplate is the maximum rated output; summer capacity is what the unit can reliably deliver on a hot day, which is typically lower.

Similarly sized plants in California

Dynegy Moss Landing Power Plant HybridBattery storage1,848 MW
HaynesNatural gas1,739 MW
Ormond BeachNatural gas1,612 MW
Geysers Unit 5-20Other1,236 MW

About this data

From EIA’s inventory of operable generators, May 2026 release. Capacity is nameplate — the maximum rated output of the equipment, not what the plant actually generates over a year, which depends on how often it runs. A 1,682 MW solar plant and a 1,682 MW nuclear plant have the same entry here and produce very different amounts of electricity.

“In service since” is the earliest in-service date among the units still listed, so a site rebuilt around newer equipment can read as younger than the site itself. All California power plants · What California actually generates