High in the Sierra Mountains, about 50 miles east of Fresno, is PG&E’s largest and most unique hydroelectric facility: the Helms Pumped Storage Plant.
The facility most people simply call “Helms” was commissioned in 1984. It’s situated against a backdrop of scenic forests and shimmering lakes, which makes it easy to forget the massive machinery at work inside the mountain here.
PG&E carved a tunnel in a mountain between two reservoirs at different elevations and pumps water up and down between them to create clean, affordable power during peak demand times.
Helms produces and stores up to 1,212 megawatts of electricity by moving water between Courtwright Lake at the higher elevation (8,200 feet) and Lake Wishon at the lower (6,500 feet). That’s enough power for 900,000 average California homes.
Currents writer Tracy Correa and videographer James Green recently visited Helms, which is so remote that workers live on-site, and offer an inside look at the facility in this Currents video.