August 4, 2004—Sun Power & Geothermal Energy has installed a 566-kilowatt DC photovoltaic (solar energy) system for the South Feather Water & Power Agency, Oroville, California. The 2.2 acre solar system, mounted on unused land adjacent to the freshwater treatment plant, provides all the electrical power for plant operations, including pumps, controls, and other equipment, during the day. The treatment plant, which runs 24/7, uses grid power at night and on rainy days.
Sun Power designed and built the solar system to perform at its highest potential. The ground-mount panels are tilted at the optimum angle to collect the most sunlight on summer afternoons. Water provided under pressure by South Feather both cools and cleans the solar panels to boost productivity. The total cost of the photovoltaic (PV) system was $4 million, of which $2 million was rebated by the California Public Utilities Commission.
The solar system produces surplus energy on sunny days, which is automatically sent to the grid for credit with PG&E in a state-mandated arrangement called net metering. The combination of solar energy and utility credits, which South Feather taps into for nighttime operations, will completely eliminate the agency’s net annual electric bill. South Feather will enjoy free energy after 2024, when the solar system will be paid off. The solar panels are warranted by the manufacturer for 25 years.
Energy costs are reportedly one of the largest expenses in running a water treatment facility. South Feather experienced spiking electric bills in the past five years, like all businesses and public works agencies in California. In 2003 South Feather’s electric bill, a significant component of the water agency’s annual budget, exceeded $160,000. The bill rose 17% annually over the previous five-year period. According to South Feather Water & Power, going solar was “essentially the only choice” to keep their rates down.
The 566-kW solar energy system, which generates the equivalent energy needed to supply 200 homes, removes South Feather’s demand on the public utility grid and adds energy to the grid during afternoon peak demand periods when California needs it the most. The system also replaces 603 tons of carbon dioxide that would otherwise be emitted into the atmosphere annually by a typical California natural gas-fired power plant. It reportedly takes 47 acres of trees to absorb this much CO2.
