Two square miles of rooftops in Southern California could start soaking up the rays and converting them into electric power under a new program from utility Southern California Edison.

The project aims to place 250 megawatts of photovoltaic panels on 65 million square feet of unused commercial rooftops.

California Gov. Arnold Schwarzenegger said that's the equivalent of 1,100 football fields.

"It is the nation's largest solar installation by a utility. When it's complete, it will produce enough power for 162,000 homes," he said at a press conference on the roof of ProLogis (NYSE: PLD) in Fontana, Calif.

Take a look at the Governator and Edison chairman and CEO John Bryson on the rooftop here >>

Denver-based ProLogis, the world's largest owner, manager and developer of distribution facilities, is one of the first companies to have its roof covered in solar panels under the program.

In the initial phase of the program, Southern California Edison, or SCE, is expected to lease 607,000 square feet of roof space from ProLogis.

Prologis said it owns 180 distribution facilities in SCE's territory comprising more than 41 million square feet, the majority of which it said is eligible for SCE's program.

SCE said it hopes to have the first solar rooftops in service by August.

The utility, a subsidiary of Rosemead, Calif.-based Edison International (NYSE: EIX), estimated that the five year program would cost $875 million.

SCE plans to put up 50 MW per year, with each individual installation to be one to two megawatts.

Schwarzenegger said, "When we need that power most during the hot summer months, this solar technology will be at its best."

SCE said the clusters of solar modules would be connected directly to the nearest neighborhood circuit, eliminating the need to build new transmission lines to bring the power to its customers.

The scale of the project is unprecedented, according to Mike Peevey, president of the California Public Utilities Commission, who responded to recent criticism of solar photovoltaic technology by University of California professor Severin Borenstein (see U.C. Berkeley professor calls solar PV technology “a loser”).

"The cost is going to come down so dramatically, that he could not make that kind of comment for this kind of project," said Peevey.

"It has some truth on the smaller applications in homes, but the beauty of this project, amongst other things, is because it is on such a scale, and the volume of units will be so large, that it'll bring down, it should bring down, the cost of solar photovoltaics across the board."

SCE said that when combined with the size of its investment, the resulting costs per unit are projected to be half that of common photovoltaic installations in California.

The company plans to begin installation work immediately on commercial roofs in Southern California's Inland Empire, San Bernardino and Riverside counties, which it said are the nation's fastest growing urban regions.

Edison International chairman and CEO John Bryson said this is just a first step for the group.

"It doesn't stop here, it goes beyond this. There is lots of distribution, large scale rooftop, across Southern California, including in the areas with the greatest heat."

Edison already gets nearly 17 percent of its energy mix from wind, solar, biomass, hydropower and geothermal sources.

Earlier this month, the company broke ground on a $1.8 billion expansion of its transmission lines specifically to handle the growing need for renewable energy in the state (see Edison expanding transmission lines for renewables).

The company said the Tehachapi Renewable Transmission Project would be capable of delivering 4,500 MW of electricity from wind farms and other projects in northern Los Angeles and eastern Kern counties when it's complete in 2013.

The rooftop project from SCE, which is still subject to approval from the California Public Utilities Commission, could give a boost to the governor's Million Solar Roofs program.

Signed into law in 2006, the governor's $2.9 billion incentive plan targets 3,000 MW of additional solar energy from homeowners and building owners who install solar electric systems by the year 2018.

California has set a goal to receive 20 percent of its electricity from renewable sources by 2010.