Ten years ago, California started giving homeowners and businesses rebates to go solar, hoping to kick-start an industry. It worked.

Now, some state officials want to do the same thing with batteries.

Legislation from state Sen. Scott Wiener, D-San Francisco, would create a 10-year incentive program for energy storage, handing out rebates to people who want to install batteries in their businesses or basements. The rebates would shrink over time, as the cost of a still-expensive technology declines.

That approach mimics the California Solar Initiative, the state rebate program that began in 2007. Many credit the initiative, which issued declining rebates until its $2.17 billion budget was spent, with helping make solar power mainstream in California — and creating businesses and jobs along the way.

“That played a hugely positive role in expanding solar in the state, so we’re looking to do that here,” Wiener said. He sees batteries and other forms of energy storage as a missing piece in the state’s renewable energy plans.

“Solar goes away at 5, 6 o’clock, when people get home and start using energy,” he said. “So we need storage.”

The bill, SB700, was passed by the Senate Appropriations Committee on Thursday and is expected to face a vote of the full Senate soon.

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The Bay Area boasts a small but growing clutch of companies that are either developing new kinds of batteries or selling existing ones to utilities, businesses and, in a few cases, homeowners. Tesla, for example, offers its Powerwall battery pack, which homeowners can pair with the company’s rooftop solar panels.

Beyond the obvious appeal of storing solar energy, batteries big enough to power buildings have other uses. Utilities are experimenting with large-scale battery packs that can help maintain the electrical grid’s stability. Businesses can use them to store energy in off-hours, when electricity prices are low, and supply it during the day when prices are higher.

But storage isn’t cheap.

The Tesla Powerwall, for example, costs $6,200 for the battery and supporting equipment, and installation costs can range from $800 to $2,000. Wider use and increased production would probably lower the cost of storage — just as happened with solar panels during the past decade — but for now, the technology remains out of financial reach for many homeowners.

The state has a long-running energy rebate program that will fund battery installations, among other things: the Self-Generation Incentive Program. But its rules have changed repeatedly, and companies consider it both erratic and woefully underfunded.

Early this month, for example, the program began accepting applications for the first time this year, offering $50.3 million for storage rebates. Within 24 hours, companies had submitted $104 millionworth of applications. The winners had to be chosen by lottery.

The application window for the program’s next round of funding, which will be worth $117.2 million, opens June 5.

“It’s a lot of people trying to get what they can in a limited amount of time, so it’s boom, bust, boom, bust,” said Jeanine Cotter, chief executive officer of the Luminalt solar installation company in San Francisco. “That’s not going to cause the market transformation we need to create the grid of the future.”

Cotter’s business just started selling Tesla Powerwalls and submitted 25 rebate applications. Twenty-three were accepted.

Wiener’s bill would split off energy storage from the rest of that rebate program, creating an Energy Storage Initiative that would begin next year and run through 2027. The California Public Utilities Commission would determine the level of funding, and the rebates would shrink on a predictable schedule.

Predictability is key, said Vic Shao, founder and CEO of Green Charge in Santa Clara. Banks don’t like backing storage companies, he said, if they don’t know what government incentives will be available in the future.

“Now, the rules are changing at least every year, so what the 10-year platform allows is for the financial community to step in,” said Shao, whose company offers battery packs for businesses, government agencies and school districts. “You can get cheaper debt. That makes the difference between a project penciling and not penciling.”

There’s certainly customer interest.

The Mountain View Los Altos High School District installed Green Charge battery packs at both of its high schools, switching them on in January 2016.

The batteries help the district cut a specific part of its monthly utility bills — the demand charge. Businesses and institutions like schools not only pay for the amount of electricity they use from the grid, but they also pay a charge based on their peak electricity demand during the month, even if that peak is very brief. Tapping the batteries when needed lowers that peak. Mike Mathiesen, associate superintendent for business services, said his school district saved $80,000 to $82,000 last year.

“Every dollar we save is a dollar that goes into the classroom,” he said. “Energy prices have gone up, and that’s something a district doesn’t have much control over. It’s not like you can turn off the lights when there’s a class.”

David R. Baker is a San Francisco Chronicle staff writer. Email: dbaker@sfchronicle.com Twitter: @DavidBakerSF