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Chokepoints
Grid Storage
Helms hydroelectric plant
19th-largest grid storage in United States of 101 · top 45% worldwide (#432 of 965)
- Operator
- Pacific Gas and Electric
- Owner
- Pacific Gas and Electric Co
- Status
- operating
- Capacity
- 1,053 MW
- Technology
- pumped storage
- Commissioned
- 1984
- Also listed as
- A power plant — this site generates as well as stores
Comparable grid storages · United States · 101 ranked
- #1Red Lake Pumped hydroelectric plant3.0 GW
- #17Northfield Mountain hydroelectric plant1.2 GW
- #18Muddy Run hydroelectric plant1.1 GW
- #19Helms hydroelectric plant1.1 GW
- #20Blenheim Gilboa hydroelectric plant1.0 GW
- #21Haiwee Pumped Storage hydroelectric plant1.0 GW
Co-located infrastructure · within 25 km
- Helms hydroelectric plant0 m · Power Plant · 1.1 GW · hydro
- Haas hydroelectric plant12 km · Power Plant · 135 MW · hydro
On the interactive map
Watercourse: Courtright Reservoir, Wishon Reservoir
SOURCE: Global Energy Monitor · Global Integrated Power, March 2026 (CC BY 4.0)