Pacific Gas and Electric Co. has entered into two utility-scale, photovoltaic solar power contracts for a total of 800 MW of renewable energy.

David Lena OptiSolar is using its thin-film PV panels at new Sacramento plant.

Under the agreements, Topaz Solar Farms LLC, a subsidiary of OptiSolar Inc., Hayward, Calif., will develop, design, construct, operate and deliver 550 MW of thin-film PV power to PG&E. The utility also signed a contract with High Plains Ranch II LLC, a subsidiary of SunPower Corp., San Jose, Calif., for 250 MW of PV power.

“These landmark agreements signal the arrival of utility-scale PV solar power that may be cost-competitive with solar thermal and wind energy,” says Jack Keenan, COO and senior vice president for PG&E. According to PG&E, both projects are contingent upon the extension of the federal investment tax credit, which is set to expire at the end of 2008, and processes to expedite transmission of the power.

Over the past six years, PG&E has entered into contracts for more than 3,600 MW of renewable power, including solar contracts that total more than 2,500 MW. PG&E now has contractual commitments for more than 24% of its future power deliveries from renewables, including wind, biomass and geothermal.

The 550-MW Topaz Solar Farm project would use thin-film PV panels designed and manufactured by OptiSolar in Hayward and Sacramento. Located on nine sq mi in the northwestern corner of the Carrisa Plains in San Luis Obispo County, the project is expected to begin power delivery in 2011 and be fully operational by 2013. According to OptiSolar spokesman Alan Bernheimer, a 1-million-sq-ft manufacturing plant in Sacramento is being converted into a solar-panel plant. It will be operational in early 2009.

SunPower’s planned 250-MW solar ranch would be located in San Luis Obispo County’s California Valley and will deliver an average of 550,000 MWh of electricity annually. The project is expected to begin power delivery in 2010 and be fully operational in 2012.

The project will employ SunPower’s proprietary crystalline PV solar cells, which generate up to 50% more power than conventional crystalline cells. At the site, the company will install its patented SunPower Tracker solar tracking systems, which tilt toward the sun as it moves across the sky, increasing energy capture by up to 30% over fixed systems while reducing land-use requirements.