The South San Joaquin Irrigation District plans to break ground on a $15.2 million 2 MW photovoltaic system - said to be the largest on-site solar power system in California, bigger than the 1.6 MW system that Google is installing on its corporate campus in Mountain View. The system is set to power a drinking water treatment plant serving four cities this summer. "From a solar exposure standpoint, it's really ideal," said Jeff Shields, irrigation district utility systems director. The water treatment plant has plenty of excess land that is flat and unshaded. Consequently, he said, with net metering, the system would offset all of the annual electricity consumed by the treatment plant. It is expected to save the district money in the long run. The irrigation district plans to tap state solar incentive money for the project and line up other financing by the end of this month, said Shields. Late last month it selected SunTechnics to carry out the installation. The German company in 2006 expanded its operation in California, which it noted is the leading solar market in the U.S. "This is going to be the biggest system in terms of [energy] production," said David Vincent, SunTechnics regional account manager. The 14-acre system will use utility grade tracking devices to move the panels to maximize solar exposure, he said. The tracking system will add 5 to 10 percent to the cost of the system compared to normal "fixed tilt" installations, he said. However, tracking systems produce 25 to 30 percent more energy and increase state solar incentive payments commensurately since they are based on energy production, he added. The irrigation district plans to install the system at its Nick C. DeGroot Water Treatment Plant, which began providing drinking water for the cities of Manteca, Tracy, and Lathrop in 2005. The district plans to expand the plant to provide water to Escalon as well. The South San Joaquin district, headquartered in Manteca, operates 130 MW of hydropower projects in conjunction with dams used to store irrigation water for a wide swath of farmland below Yosemite. The district also is interested in becoming a retail power provider in its area by acquiring the local distribution network from Pacific Gas & Electric (Circuit, June 23, 2006). That move would reduce electricity rates by 15 percent, according to the district.