SunPower and General Electric Energy Financial Services are partnering to build solar power installations generating 8 megawatts in California by the end of the year.

The five projects include what could become the nation's largest solar panel installation on one roof, capable of 2.3 megawatts, at Toyota Motor Sales' Parts Center. Construction is set to start next month.

GE Energy Financial Services is acquiring a majority equity interest in the projects for an undisclosed amount. It will own the systems built and run by SunPower, a maker of high-efficiency solar panels.

The San Jose, Calif.-based company, which is owned by Cypress Semiconductor Corp., first partnered with GE's energy investment arm in 2006 on a solar plant in Portugal.

The four other plans for California include a 1-megawatt solar array covering eight buildings at an HP printer research and development center in San Diego.

A 1-megawatt solar tracking system atop a parking lot will provide shade and power for Agilent Technologies, a maker of scientific measurement tools, in Santa Rosa.

In northern Lake County, ground-mounted solar systems for a jail and two wastewater treatment plants will generate 2.4 megawatts. A 10-acre solar system will provide energy to a water district in Murrieta in the south.

SunPower's panels are also being set up at North America's largest solar installation, totaling 14.2 megawatts, at Nellis Air Force Base in Nevada. The company recently announced plans to build an 18 megawatt power plant in Spain.

GE Energy Financial Services manages $16 billion in assets and invests $5 billion annually in energy and water. It aims to dramatically expand its $2 billion renewable energy portfolio. Parent company GE has been making massive investments in renewable energy through its "ecomagination" campaign.