Helms Pumped Storage Plant, Pumped-storage power station in California, United States

Helms Pumped Storage Plant is a pumped-storage power station in the Sierra Nevada of California, United States. It consists of two reservoirs at different elevations, connected by tunnels and a powerhouse carved into the rock, and it generates electricity by moving water between them.

The Helms Pumped Storage Plant was built in the 1980s to help meet peak electricity demand in California. It was later upgraded to increase its capacity and efficiency, and it remains one of the largest of its kind in the state.

The plant is a key part of California's effort to store energy from renewable sources, and its reservoirs are visible landmarks for hikers in the area. Local residents often see the upper reservoir as a sign of the state's push toward cleaner power.

The plant is not open to the public, but you can see the upper reservoir from nearby trails in the Sierra National Forest. Access to the area is seasonal, and roads may be closed in winter, so check conditions before you go.

The powerhouse is located deep underground and is accessed by a long tunnel, which is unusual for visitors to see. The plant can switch from pumping to generating in minutes, helping to balance the grid when demand changes.