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With a perennial energy problem in California, Sacramento lawmakers are now looking to harness solar energy (search) to reduce the state's burden, but the building industry is wary, saying the plan is built on unsure economics and too much government interference.

"Harnessing the sun's energy and putting that to good use sounds good, but when you boil it down," it is not that practical, said Tim Coyle, vice president of the California Building Industry Association (search).

Last month, the California state Senate passed a bill requiring builders to install on new homes solar photovoltaic energy systems (search), which are solar cells that capture the energy of the sun. According to the plan, new homes would generate much of their own energy. When the cells generate more energy than the homes can use, the surplus would be sent to the grid. At night, these homes would take power from the grid because the cells would not be generating any energy.

Environmentalists and several state lawmakers have lined up behind the proposal. Among the many claimed benefits are increased security for California's energy supply, environmental protection through the building of fewer power plants and the potential long-run economic gains for homeowners.

"Solar is clean. It follows the principle of distributed generation, which not only keeps us from keeping on building new power plants, but it also means you don’t have to build and maintain expensive distribution lines," state Sen. Kevin Murray (search), D-Los Angeles, the bill's sponsor, told Foxnews.com.

Although significant initial costs are attributed to solar power, advocates say homeowners would save on each power bill because they would only be charged the difference between the energy their homes sent to the grid and that which they took away.

In describing the merits of the proposal, Murray also appealed to a prime American value: self-sufficiency.

"More important than anything else is a certain amount of control over our destiny," he said. This is true not only for the nation and California, but also for the individual consumer, "so they don’t have to worry about whether some bureaucrat or some guy at the power company made the right decision."

Without disputing the intentions of solar power advocates, builders say it would be more cost-effective to address the inefficiencies in California's older homes than to build solar energy systems on new homes, which represent a tiny percentage of the state's total homes.

Coyle said other ways are available to save on energy, including caulk and insulation, which may not be as romantic as solar power, but may be more effective.

"Energy inefficiency is much more pronounced for homes built prior to 1991," Coyle said. The state can "accomplish a lot more in aggregate energy savings with caulking windows and energy-efficient insulation than a solar-based strategy."

High tech and sunny, California is a natural location for solar energy, say proponents. It rates third behind Japan and Germany in harnessing the sun. But California is not alone in solar energy initiatives. Florida, New Jersey and New York all have efforts to promote solar power.

Originally, Murray's bill had mandated that 25 percent of all new homes in 2006 — approximately 135,000 total are estimated to be built that year — come with solar systems, with the percentage increasing each year. Supporters said using that number, if two-kilowatt solar PV systems are installed on new homes in 2006, California’s current solar market would immediately increase by the size of one power plant, and three times the state's current solar market. That's still less than 1 percent of the state's total energy needs.

Quantifying the environmental benefits, Environment California (search), a group that focuses on protecting the state's air, water and open spaces, estimated that if California were to require 20 percent of new homes to be equipped with solar cells in 2006 and increase that requirement by 10 percent each year to reach 60 percent in 2010, by that time, a total of 10 power plants that otherwise would have been needed to meet housing energy needs would not have to be built.

In terms of air pollution benefits, the group estimated that by 2010, at least 72 tons of nitrogen oxide pollution and nearly 200,000 tons of carbon dioxide pollution would be prevented each year. That's equal to every owner of a solar home not driving for four to five months out of the year, representatives say.

"This is exactly the type of situation in which the government should get involved in: To jump-start an industry that has a clear environmental and economic benefits for the state of California," said Bernadette Del Chiaro, clean energy advocate for Environment California.

But the bill's stiffest opponent, the California Building Industry Association, disagrees, arguing the technology doesn't match the goals.

"We oppose the bill for a fairly simple reason: This is a mandate for what could be a promising technology, but isn’t fully developed, and when it comes to the cost of $20,000 per home, it becomes a tax on housing," said Coyle.

The cost of building a two-kilowatt system is disputed. Environment California says it would cost $10,000 and because of tax incentives and savings on monthly power bills, the net cost would be next to nothing for the homeowner. Advocates say it is important to equip homes with solar systems at the time they are built because it is more expensive to do so afterwards.

Although CBIA opposes this bill, Coyle said the industry "will work on an alternative approach that helps to introduce photovoltaics into the marketplace in a cost-effective way."

The bill passed by the state Senate left it undetermined what percentage of houses must have the solar cells. Should the General Assembly pass the bill, that decision will have to be made over the next few months by the legislature and Gov. Arnold Schwarzenegger (search).

The state house may consider the bill this month. While Schwarzenegger has expressed support for solar power, he has also said any state requirement will be done in consultation with the builders.