Study: L.A. County Could Power Half of California With Rooftop Solar

Putting solar panels on suitable undeveloped rooftop space in Los Angeles County could create about half of the electrical power California needs on a typical summer day, and developing just five percent of that rooftop capacity would generate almost 30,000 jobs.

That's according to a mapping study released Wednesday by the UCLA Luskin Center for Innovation, which conducted the study for the Environmental Defense Fund. Los Angeles County's non-solarized rooftops could be generating up to 22,984 megawatts of electricity during the day.

Statewide, peak demand in the hottest part of summer generally runs in the neighborhood of 60,000 megawatts; absent a heatwave, the state's summer peak demand often runs lower than 50,000 megawatts. That means Los Angeles County's rooftops could conceivably generate half the state's power on most summer days, and perhaps more during cooler parts of the year.

The study, called the "Los Angeles Solar and Efficiency Report: Atlas of Investment Potential for LA County" (LASER), also identified almost 1.5 million buildings in Los Angeles County that were built before 1978. That's when the state's modern energy efficiency building codes went into effect. Buildings built to earlier standards likely use more energy than they need to, offering the possibility that straightforward energy conservation programs targeted at those buildings could cut down significantly on the county's energy use.

In some parts of the county, such as the San Gabriel Valley, as much as 80 percent of the building stock was built prior to 1978. That indicates that there's a whole lot of opportunity to boost the county's energy efficiency.

LASER also charts the sections of the county that are facing the largest increases in temperature -- the mountains seem to be likely to warm more than the flats -- and the sections of the populace that are most vulnerable to climate change-related ills. Probably unsurprisingly, people in less-affluent neighborhoods make up the bulk of the vulnerable.

The intent of the study is to offer a guide for policymakers as to how to best spend proceeds from the state's carbon cap and trade auctions and Proposition 39 to reduce the state's contribution to global warming.

"Combined with California's innovative climate policies, the 'LASER' Atlas can impact how the region invests new state resources to address pressing environmental challenges while providing job opportunities in its most impacted communities," said Luskin Center deputy director Colleen Callahan. "Together, EDF and the Luskin Center have created a powerful resource that can help the L.A. region unlock a cleaner energy future."