GE, SunPower & California County Construct Solar Power System on Two WWTPs

Feb. 20, 2009
Savings to county residents may reach $5 million over 20 years

SunPower Corp., GE, California’s Lake County and the Lake County Sanitation District (LACOSAN) have announced the completion of a 2.2-megawatt solar-electric power system on three sites, including the county jail and two wastewater treatment plants. Combining this new system with an existing 1-megawatt solar power installation, Lake County is now home to the largest solar power installation on county facilities in California. The combined 3.2-megawatt system produces the equivalent of 94% of the facilities’ electricity requirements.

“We expect these solar power installations to save Lake County taxpayers and ratepayers between $1.6 million and $5 million over the next 20 years, depending on utility rate increases,” said Mark Dellinger, special districts administrator for LACOSAN. “SunPower offered high-efficiency technology that maximizes the amount of solar power generated, and a turnkey solution that helped to accelerate design and construction.”

Hosting the solar installation helps further Lake County’s commitment to building a sustainable community infrastructure. The wastewater that LACOSAN treats, recycles and transports at the two treatment plants is used to recharge another alternative energy source—geothermal—that generates power for homes and businesses. The county’s program includes its commitment to energy efficiency, The Geysers—the world’s largest complex of geothermal energy—and other alternative sources of energy.

“These solar facilities represent a critical part of Lake County’s overall energy program,” said Denise Rushing, chair of the Lake County Board of Supervisors. “The County truly appreciates the innovation demonstrated by SunPower and GE, and for their partnership with us to make this happen.”

GE Energy Financial Services, a unit of GE, in partnership with SunPower, financed and owns the system as well as the associated renewable energy credits and environmental benefits. Using conversion formulas provided by the U.S. Environmental Protection Agency, the 2.2-megawatt SunPower system will avoid more than 131 million lb of carbon dioxide emissions over the next 30 years, equivalent to removing close to 11,000 cars from the road.

Under a SunPower Access power purchase agreement (PPA), the partnership is selling electricity to the county and LACOSAN at rates that are competitively priced against utility rates, providing them with a long-term hedge against rising peak power prices.

“Lake County and LACOSAN took advantage of the SunPower Access PPA to build and host emission-free solar power plants at their facilities with no upfront capital expenditure,” said Tom Werner, chief executive officer of SunPower. “We applaud the county and district for taking the lead with this showcase installation that demonstrates how solar makes good financial sense for public agencies today.”

At the county and LACOSAN facilities, SunPower designed and installed a system that utilizes SunPower solar panels, the most efficient solar panels on the market today, with the SunPower Tracker system. The Tracker follows the sun’s movement during the day, increasing sunlight capture by up to 30% over conventional fixed-tilt systems, while significantly reducing land-use requirements.

The SunPower arrays in the system include:
• A 602-kilowatt installation at the Lake County Jail;
• Two installations at the Northwest Wastewater Treatment Plant, including one 281-kilowatt array and one 764-kilowatt array; and
• A 522-kilowatt array at LACOSAN’s Southeast Wastewater Treatment Plant.

Source: Lake County Sanitation District, SunPower, GE

Image courtesy Institute of Chemical Research of Catalonia (ICIQ).
All images courtesy of Ecosorb.