Kyocera Solar, Inc. announced that its 1.135-megawatt (MW) solar array at the Alvarado Water Treatment Facility in San Diego, Calif., has exceeded performance expectations consistently since it began operating in February 2007, as documented by power generation data.
The Alvarado facility will increase its water treatment capacity by 67 percent next year, from 120 million gallons per day to 200 million. To alleviate the cost of the expansion, the City of San Diego became one of the first in the nation to adopt a Power Purchase Agreement. Also known as a “PPA,” this contract between an electricity producer and a host site owner helps curb energy costs in a sustainable manner.
The PPA allows the Alvarado Water Treatment Plant to host ? without owning ? the Kyocera solar modules. The facility’s PPA partner owns, operates and maintains the entire system. For a period of 20 years, the City of San Diego has agreed to purchase every kilowatt hour that the system produces, at a fixed price, with an annual cost escalation of just one percent. That’s much lower than the expected annual increase in utility rates.
Taking a conservative approach and compounding the difference between 2.5 percent and 1 percent annual rate increases, the City estimates savings of about $325,000 during the course of its 20-year PPA. If rates rise an average of 4 percent per year, the savings will be about $650,000.
The system’s environmental benefits are equally impressive. The solar installation occupies previously unused space atop the concrete roofs of three water storage reservoirs. Its annual power output represents the energy equivalent of about 2,640 barrels of oil. That’s enough to offset about 580 metric tons of carbon dioxide each year — an impact comparable to about 400 acres of green forest.
The project reflects a major initiative to increase California’s renewable energy mix to 33 percent by 2020. Consequently, the Alvarado Water Treatment Plant is attracting interest from other municipalities considering solar power. The City of San Diego, already a solar energy leader, is now pursuing PPAs for its other water treatment facilities.
According to Ian Knox, Kyocera’s Southern California sales manager, large-scale solar electric generating systems are becoming commonplace in many regions of the globe.