Solar energy to power pumping station

The 1 megawatt single-axis solar tracking system will provide renewable energy to an existing pump station that supplies the NCPA Geysers Geothermal Energy Plant near Middletown, California. The array will be used to collect solar power to pump wastewater into the geysers, which is in turn used to generate renewable geothermal power. The photovoltaic array will start generating clean renewable power beginning in September 2008.

The $8.2 million installation consists of 6,300 solar modules that will produce 2.2 million kilowatt hours of electricity annually, enough to power 300 homes and offsetting nearly 800,000 lbs of carbon dioxide per year. The solar plant will supplant PG&E-provided grid power that had been powering the pumps. Replacing grid power to operate the pump station with a nonpolluting fuel source will also assist the state in meeting its greenhouse gas emission goals.

“The significance of this project is the creative use of clean energy and a system design in which we will deploy one renewable energy source to power another,” said Jim Pope, NCPA General Manager. “This solar investment demonstrates our continued commitment to investing in environmentally responsible resources, reducing our carbon footprint and lowering costs for our utilities and public power customers.”

“This unique system shows that solar power can be used for large-scale industrial – or in this case energy generating applications,” said Steve McKenery, SPG Solar Vice President of Commercial Development. “The project is an important breakthrough in the use of solar power on a large scale and should help other industrial energy users understand the potential for solar power.”

The NCPA Geysers Geothermal Plant uses wastewater from Lake County and injects it into the geothermal reservoir. The reservoir converts the wastewater into steam, which is used by geothermal power plants to produce electricity. Currently, about 70 per cent of steam produced from by the reservoir is due to wastewater injection. This operation also provides an extremely effective wastewater disposal solution for Clearlake.

NCPA is a nonprofit California joint powers agency established in 1968 to generate, transmit, and distribute electric power to and on behalf of its fifteen members.