GridPlants

Pumped-storage hydro power plants in the United States

Pumped-storage hydro units in the 2025 EIA-860 data total 22.2 GW of nameplate capacity, 1.6% of the US fleet. It is the main source at 33 plants; California has the most, with 3,704 MW. More of today’s pumped-storage hydro capacity came online in 1973 than in any other year (4,613 MW). The oldest unit still working went into service in 1927 at Horse Mesa, Arizona.

When today’s pumped-storage hydro capacity was built

Above the line: capacity still operable in 2025, by the year each unit came online. Below: pumped-storage hydro capacity retired in each year, including plants that have closed completely (EIA’s retired-generator file).

1 GW2 GW3 GW4 GW192019301940195019601970198019902000201020200

States with the most pumped-storage hydro capacity

  1. California3,704 MW
  2. Virginia3,109 MW
  3. South Carolina3,041 MW
  4. Michigan1,979 MW
  5. Massachusetts1,834 MW
  6. Tennessee1,714 MW
  7. Georgia1,635 MW
  8. Pennsylvania1,484 MW
  9. New York1,240 MW
  10. Missouri600 MW
  11. Colorado508 MW
  12. New Jersey453 MW
  13. Washington314 MW
  14. Oklahoma259 MW
  15. Arizona194 MW

Largest units

The single biggest pumped-storage hydro generator is unit 1 at Bath County, rated at 477 MW.

PlantStateUnit sizeOnline
Bath CountyVirginia477 MW1985
Bath CountyVirginia477 MW1985
Bath CountyVirginia477 MW1985
Bath CountyVirginia477 MW1985
Bath CountyVirginia477 MW1985
Bath CountyVirginia477 MW1985
Raccoon MountainTennessee428 MW1979
Raccoon MountainTennessee428 MW1978

The 25 largest pumped-storage plants

RankPlantStateRuns onCapacityFirst unitOperator
1Bath CountyVirginiaPumped-storage hydro2,862 MW1985Virginia Electric & Power Co
2LudingtonMichiganPumped-storage hydro1,979 MW1973Consumers Energy Co (MI)
3Raccoon MountainTennesseePumped-storage hydro1,714 MW1978Tennessee Valley Authority
4CastaicCaliforniaPumped-storage hydro1,682 MW1972Los Angeles Department of Water & Power
5Bad CreekSouth CarolinaPumped-storage hydro1,680 MW1991Duke Energy Carolinas, LLC
6Northfield MountainMassachusettsPumped-storage hydro1,168 MW1972FirstLight Power Resources, Inc. - MA
7Muddy RunPennsylvaniaPumped-storage hydro1,072 MW1967Constellation Power, Inc
8Helms Pumped StorageCaliforniaPumped-storage hydro1,053 MW1984Pacific Gas & Electric Co.
9Blenheim GilboaNew YorkPumped-storage hydro1,000 MW1973New York Power Authority
10Rocky Mountain Hydroelectric PlantGeorgiaPumped-storage hydro848 MW1995Oglethorpe Power Corporation
11JocasseeSouth CarolinaPumped-storage hydro774 MW1973Duke Energy Carolinas, LLC
12Bear SwampMassachusettsPumped-storage hydro666 MW1974Bear Swamp Power Company LLC
13Richard B RussellGeorgiaPumped-storage hydro628 MW1985USCE-Savannah District
14Fairfield Pumped StorageSouth CarolinaPumped-storage hydro587 MW1978Dominion Energy South Carolina, Inc
15Yards Creek EnergyNew JerseyPumped-storage hydro453 MW1965Yards Creek Energy
16Seneca Generation LLCPennsylvaniaPumped-storage hydro438 MW1970Seneca Generation LLC
17W R GianelliCaliforniaPumped-storage hydro424 MW1967California Dept. of Water Resources
18Taum SaukMissouriPumped-storage hydro408 MW1963Union Electric Co (MO)
19Wallace DamGeorgiaPumped-storage hydro321 MW1979Georgia Power Co
20Cabin CreekColoradoPumped-storage hydro300 MW1967Public Service Co of Colorado
21SalinaOklahomaPumped-storage hydro259 MW1968Grand River Dam Authority
22Lewiston NiagaraNew YorkPumped-storage hydro240 MW1961New York Power Authority
23Mount ElbertColoradoPumped-storage hydro200 MW1981U S Bureau of Reclamation
24J S EastwoodCaliforniaPumped-storage hydro200 MW1987Southern California Edison Co
25Hiwassee DamNorth CarolinaPumped-storage hydro166 MW1940Tennessee Valley Authority

All 33 in the finder