Southern California Edison (SCE) has awarded 36 contracts to independent power producers to generate emission-free energy using photovoltaic solar panels.

The panels will be installed on 31 unused rooftops and five ground-mount sites in SCE’s service territory, and will generate about 60MW of energy for the company’s customers.

The solar rooftop project, approved by the California Public Utilities Commission in June 2009, will generate a total of 500MW power on otherwise unused large warehouse roofs.

Half of the 500MW will be from independent power producers who respond to SCE’s request for offers, with the remaining 250MW owned and operated by SCE.

According to SCE, the project will make the resulting cost per unit more cost effective than more common residential photovoltaic sites in California, reducing installation overheads.

When complete, the solar panels will appear on about 250 otherwise unused warehouse roofs.