Helms Pumped Storage Plant
| Company type | Power station |
|---|---|
| Industry | Hydroelectric power generation |
| Founded | June 30, 1984 |
| Headquarters | Fresno, California , United States |
| Products | Electricity |
| Owner | Pacific Gas and Electric Company |
The Helms Pumped Storage Facility is situated approximately 50 miles (80 kilometers) to the east of Fresno, California, within the Sierra National Forest of the Sierra Nevada mountain range. It takes advantage of Helms Creek canyon along the North Fork of the Kings River for off-stream water storage and operates using pumped-storage hydroelectric principles. Initially conceptualized in the early 1970s, construction commenced in June 1977, with commercial production beginning on June 30, 1984. The plant boasts a generation capacity of 1,212 MW and is under the ownership of Pacific Gas and Electric Company.
Design and operation
Electricity generation at the facility involves transferring water between two reservoirs positioned at different elevations. When electricity demand peaks, water is released from the upper reservoir down to the power generation units, subsequently flowing into the lower reservoir. Conversely, during times of reduced demand, water is pumped back uphill to the upper reservoir by pump-generators that function as turbines in reverse. The station can initiate power production within eight minutes, allowing for swift adaptation to fluctuations in energy demand. Although energy consumption for pumping exceeds generation output, pumping is strategically conducted during off-peak hours using excess grid electricity at reduced rates.
The upper reservoir, known as Courtright Reservoir, is located at an elevation of , with a storage capacity of . The lower reservoir, called Wishon Reservoir, lies at an altitude of , holding . Water moves from the upper to the lower reservoir through a head-race tunnel measuring , followed by a steel penstock spanning , which divides into three separate penstocks supplying individual pump-generators. After passing through the turbines, water exits via a tail-race tunnel measuring . The system operates with an effective hydraulic head of . The subterranean powerhouse situated near Wishon Reservoir contains three Francis pump turbine-generators, each rated at 404 MW.
The Helms facility was engineered to operate in conjunction with PG&E’s Diablo Canyon Nuclear Power Plant, sharing a dedicated high-voltage transmission line that supports grid reliability and optimizes energy dispatch during periods when the nuclear plant is active.
See also
External links
- Helms: Power from Water, Human Engineering – PG&E video detailing the plant’s functionality
- Energy infrastructure completed in 1984
- Hydroelectric power plants in California
- Pumped-storage hydroelectric power stations in the United States
- Buildings and structures in Fresno County, California
- Sierra National Forest
- Pacific Gas and Electric Company
- Dams completed in 1984
- Underground power stations
- 1984 establishments in California