City of San Diego Mayor Jerry Sanders today launched a new 1.135 megawatt solar power installation at San Diego’s Alvarado Water Treatment Plant. The panels produce about 20 percent of the plant’s power, with annual electricity savings estimated at $40,000.

The Alvarado photovoltaic installation was built under a power purchase agreement (PPA) with SunEdison, North America’s largest solar services company. Under the agreement, San Diego citizens benefit from clean, solar energy with no upfront cost, thereby avoiding an estimated $6.5 million in capital installation. SunEdison built, owns and will maintain the solar system. SunEdison will sell the solar energy to the City’s Water Department at costs lower than SDG&E rates.

The 1-megawatt water treatment plant site is the first of a multi-year solar deployment at City facilities that will eventually produce 5 megawatts of solar power and will become the largest municipal system in California, surpassing Google’s planned 1.6 megawatt solar system in Mountain View, California.

“Installing 5 megawatts of solar panels on City-operated property is a major step toward meeting the City’s target of providing 50 megawatts of renewable fueled power generation by 2013,” said Mayor Sanders.

The Alvarado installation has 6,128 photovoltaic solar panels located atop the concrete roofs of all three water storage reservoirs, a total area covering approximately 4.33 acres. Each panel measures 4.5×3.5-feet. The solar power system, with the capacity to produce 1.602 million kilowatt hours of electricity per year, will have a measurable environmental impact and will reduce annual carbon emissions equal to 219 cars driving 12,500 miles annually.

As part of a planned 5 megawatt solar system deployment, the Alvarado solar array marks another step forward in providing clean, renewable energy for San Diego, which has been recognized as the nation’s #1 “Green Power Partnership” city by the Environmental Protection Agency since 2006. The City and SunEdison are investigating an additional 4 megawatts of solar projects at other San Diego sites including the Otay Water Treatment Facility and the Black Mountain Reservoir.

Mayor Sanders added, “When the 5 megawatts of solar systems are fully installed, they will support California’s goal of increasing the percentage of renewable energy in the state’s electricity mix to 20 percent by 2017,” he said. “We are gratified to be able to work with SunEdison to make predictably-priced clean solar energy available to the city.”

“SunEdison is extremely proud to work closely with San Diego in creating a solar array that will generate clean solar energy for the community. This is a milestone for San Diego and for solar in California,” noted Jigar Shah, CEO of SunEdison, North America’s first and largest solar services provider. “San Diego is a leader in pursuing clean solar energy and renewable energy goals. Through the Power Purchase Agreement solar services model, San Diego is able to achieve predictable pricing in solar energy costs and do so without incurring a capital outlay. SunEdison is pleased to have built, to own and to maintain such an important solar power array.”

San Diego currently produces 18 megawatts of renewable energy annually to help power City facilities. City photovoltaics including the Alvarado plant currently generate approximately 1.8 million kilowatt-hours annually. The remainder comes from methane gas generated by the City’s Miramar Landfill that powers wastewater treatment plants, and a 1.35 megawatt hydro generator.