So state Sen. Byron Sher, D-San Jose, who wrote the current law, put that campaign promise into a bill this year: SB 1478.

That legislation is now among a handful of key energy bills that lawmakers are scrambling this week to pass and put on the governor's desk before the legislative session ends. Hearings on all the bills are scheduled for today, though final votes probably will be Friday, when lawmakers hope to adjourn so Republicans can attend their national convention in New York.

Schwarzenegger has taken no position on Sher's bill so far, but environmental groups are hopeful it will pass the Legislature and win the Republican governor's signature.

"It's a great policy," said Rico Mastrodonato, Northern California director for the California League of Conservation Voters. "It's just important for our long-term viability, our security and our energy needs to have an expanding renewable energy portfolio. We should set goals and accelerate them."

Utilities generally agree with the idea, but have quibbled with the details.

Pacific Gas & Electric, for instance, wants public utilities in cities such as Santa Clara, Palo Alto, Sacramento and Los Angeles to be held to the same standard. Current law and the bill exempt them.

"We believe that for the entire state to benefit, all utilities, public and private, should be required to abide by the same standards," said PG&E spokesman Ron Low.

Of California's three major investor-owned utilities affected by the bill, only San Diego Gas & Electric would have difficulty meeting the goal. SDG&E currently receives just 1.8 percent of its power from renewable sources, according to legislative analysts.

Pacific Gas & Electric gets 12 percent of its power from renewable sources and Southern California Edison gets 17 percent, legislative analysts said.

Situated at the southern end of the state, SDG&E doesn't have access to the hydroelectric power available to the other utilities, or enough transmission-line capacity to tap renewable energy outside its service area.

So to make up for that disadvantage, the bill proposes a "renewable energy credits" program. SDG&E could buy credits for electricity from a Northern California wind-power generator, for example, while the energy itself is delivered to another utility.

Similar programs already are in place in Massachusetts and Texas, and also have been used in programs to reduce acid rain and smog from power plants.

"We certainly support the 20 percent goal, and the credit program as outlined in the bill, and the recognition that we need more transmission to access more of these resources," said Ed Van Herik, an SDG&E spokesman.

Two bills aimed at promoting solar-power use in California also are scheduled for Thursday hearings. One, SB 199 by Sen. Kevin Murray, D-Los Angeles, incorporates Schwarzenegger's proposal last week to fulfill a campaign vow and get more new homes built with solar power.

After some technical changes, it has won the backing of environmentalists, even though Murray's original bill had tougher provisions requiring builders to equip half of new homes with solar power by 2020.

The current version backed by Schwarzenegger would require builders to offer solar power to new-home buyers beginning in 2008, and provides $230 million in increased funding for rebates to subsidize the system's cost. It also would allow a 0.05 percent rate increase if needed to reach a goal of 1 million more solar homes by 2013.

Sen. Debra Bowen, D-Redondo Beach, has a competing solar bill, SB 118, that uses different funding to avoid a possible rate increase - - unused money set aside to pay customers who agree to have service interrupted when power supplies are dangerously low.

Bowen's bill would apply to commercial as well as residential property, and requires passage of an Assembly bill that sets a regulatory framework for California's electricity system.

That bill, AB 2006 by Assembly Speaker Fabian Nunez, D-Los Angeles, could be voted on in the Senate today.

Nunez' bill is backed by consumer advocates who favor a retreat from the market-based deregulated system that imploded in a costly crisis three years ago. Private power generators such as San Jose- based Calpine and business groups oppose it as a return to expensive monopoly utility power.