Across the country, and particularly in California, where energy costs have spiked, more solar roofs are being installed each year.

Each school has its own webpage where parents, ex-pupils, local businesses, and other supporters can buy squares of a 'virtual' solar roof.

Once they have raised the total cost of the solar roof, they can erect it.

These solar roofs are in additon to 30 roofs that we installed over a year ago.

The Riverside distribution center hosts California's largest solar roof installation.

Using a solar roof, solar cells can provide electric power.

But because of the bale walls' mass, he said, straw provides good insulation, especially along with a passive solar roof.

Provides information about a government initiative for installing one million solar roofs by 2010.

His unit, he said, is negotiating with a "big box retailer" to install solar roofs on some of its stores.

Just this month it invested in new projects to use solar roofs to power two San Diego schools.