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SystemsUp to date · Jan 15, 2026

Pumped Storage Hydropower

A grid-scale energy storage system using two reservoirs at different elevations. Excess electricity pumps water uphill; when power is needed, water flows downhill through turbines. About 22 GW of capacity exists in the U.S.

Why It Matters

Pumped hydro is the largest and most proven form of grid-scale energy storage — storing far more energy than all batteries combined. It provides 8-12+ hours of storage and lasts 50-100 years.

Related Topics

hydroelectric power

Related Terms

Hydroelectric Dam

A structure that impounds water in a reservoir, releasing it through turbines to generate electricity. The energy comes from the gravitational potential of water stored at elevation.

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