At least 10 times a day Andrew Kin clicks onto the Internet for the pure joy of watching his electricity meter run backward.
The 30-year-old business consultant placed an array of rooftop solar panels on his Los Angeles area duplex last fall, and thanks to a Web site provided by his installer he has watched his monthly electricity bills drop, in real time, from $50 to about $10.
"I make up a little chart every day," Kin said. "This past week was sunny, so I was electricity neutral about every other day, which I'm excited about."
Friday, Gov. Arnold Schwarzenegger is expected to sign legislation that will make it possible for more Californians to sell the electricity they produce back to their utilities at retail prices.
The legislation, written by Assemblywoman Nancy Skinner, a Democrat, doubles to 5 percent the overall amount of energy that California's investor-owned utilities must buy back.
Previously, state law required electric companies to sign so-called net-metering contracts for up to only 2.5 percent of their load.
Solar advocates said the net-metering boost would allow consumers to recoup their investment faster, which is critical to California's goal of installing a million rooftop arrays by 2017.
Roughly 50,000 California homes benefit from net-metering today, a number that would need to grow rapidly if the state is to reach its goal of obtaining 3,000 megawatts from rooftop solar.
California leads the nation in solar energy, accounting for more than 65 percent of all the solar installed in the U.S., Skinner said. "Net metering has been absolutely fundamental to that success," she said.
But public and private utilities have been wary of encouraging rooftop solar installations, preferring large, centralized arrays.
Many of these big plants -- which are proposed to be built in environmentally fragile desert regions and require transmission lines through populated areas -- have attracted controversy.
The 2.5 percent rooftop solar cap, originally set into law at the utilities' insistence, would have halted new net-metering contracts for businesses, schools and consumers served by Pacific Gas & Electric Co. by next year. It would have eventually done the same at other utilities.
The state's major investor-owned utilities, which endorse the new 5 percent cap, had fought off two earlier bills, one to eliminate the cap altogether, and another to raise it to 10 percent.
"California has millions of buildings, the vast majority of which could host a solar system," said energy specialist Bernadette del Chiaro of the nonprofit group Environment California.
"We haven't reached our true potential for solar power, partly because of a lack of support by utilities who still see customer-owned solar power as a threat to their business model. California should ultimately not limit the number of people capable of going solar, plain and simple, even if that is what utilities clamor for."
Public utilities such as the Los Angeles Department of Water and Power do not have a mandated cap, but solar advocates have been critical of the DWP's commitment. The utility has only 2,941 installed and pending rooftop systems representing only 0.6 percent of its power load.
Nonetheless, Kin said that the $22,000 cost of his solar rooftop system dropped to $8,000 with $11,000 in incentives from DWP, plus tax breaks.
During the day, when he's not home, his panels feed electricity to the DWP. At night, when he returns, he turns on lights and television, and sucks power from the grid as in most homes.
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