Sammy Roth

The Desert Sun

Kevin de León has promised to lead the resistance to President Trump. A new bill could make good on that promise.

The California Senate leader has introduced legislation that would require the Golden State to get 100 percent of its electricity from climate-friendly energy sources by 2045. That's a big step up from the state's current renewable energy mandate, 50 percent by 2030 — a target that's only been on the books for a year and a half, and that California is still a long way from meeting.

Under Gov. Jerry Brown, California has become a world leader in efforts to limit global warming, which is caused primarily by the burning of fossil fuels. De León's 100 percent clean energy proposal would up the ante considerably — and fly in the face of Donald Trump's agenda. The president has repeatedly called human-caused global warming a "hoax," despite overwhelming scientific evidence that it's real and dangerous, and has pledged to boost America's production of climate-polluting coal, oil and natural gas, which he says will create millions of high-paying jobs.

THE CURRENT: Sign up for The Desert Sun's energy and water newsletter

De León's bill would require California to hit 50 percent renewable energy by 2025, five years sooner than under current law, and phase out fossil fuels entirely by 2045. It's not yet clear whether the Senate leader will move forward the proposal, which he introduced before the state's bill-filing deadline on Friday, almost certainly to serve as a placeholder for more detailed legislation that could be fleshed out later.

Still, clean energy advocates celebrated the proposal. De León's legislation reflects the Golden State's "moral imperative" to slash climate pollution, said Jim Woodruff, president of the Large-scale Solar Association, a Sacramento trade group that has worked with de León on the bill.

"Whether it’s a direct response to what’s happening in Washington, I don't know, but it's certainly an indication that California will continue to lead in this area," said Woodruff, who is also an executive at First Solar, which has built several large solar farms in the desert Southwest. "It's the sixth-largest economy in the world. I think by putting these goals out, it's making a pretty powerful statement, not only in the U.S., but globally, that if we set out the goals and put the resources to it, those goals can be achieved."

So far only one U.S. state, Hawaii, has a law requiring 100 percent renewable energy, according to the National Conference of State Legislatures. Hawaii has also set a deadline of 2045.

A spokesperson for de León declined to make the senator available for an interview. But the Los Angeles Democrat has worked closely with Brown to pass other landmark climate bills, writing the 2015 law that established the 50 percent clean energy mandate. And he's made it clear he's eager to push back against the Trump administration on immigration, energy and other issues.

"California was not a part of this nation when its history began, but we are clearly now the keeper of its future," de León and state Assembly leader Anthony Rendon said in a joint statement the day after Trump's election in November.

RELATED: The solar industry isn't afraid of President Trump

Experts say Trump's energy plan is unrealistic, and not just because it ignores the need to reduce emissions of climate-altering greenhouse gases. Trump and congressional Republicans have said they will revive the shrinking coal industry by repealing former President Barack Obama's environmental regulations, but the reality is that market forces — especially the rise of cheap natural gas, made available by the drilling technique known as fracking — have been a major cause of coal's decline. Unless Trump can limit natural gas production, coal will continue to hurt, experts say.

Meanwhile, California's plans to scale up renewable energy look increasingly realistic. The Golden State got 27 percent of its electricity from solar, wind and other clean sources in 2016, according to the California Energy Commission. The state's sprawling deserts have been an epicenter of renewable energy growth, with several huge solar farms opening in eastern Riverside County, near the Coachella Valley. The solar industry has become an economic force here, creating 100,000 jobs in California and 260,000 jobs nationally by late 2016, according to an industry-backed nonprofit.

Getting to 100 percent renewable energy may not be simple, but experts say it can be done without significant increases to electricity rates, a concern often raised by fossil fuel supporters.

"Technically and economically, it's pretty straightforward," said Mark Jacobson, a Stanford University engineering professor who has studied the costs and benefits of phasing out fossil fuels.

READ MORE: Why fighting climate change won't destroy the economy

The falling costs of wind and solar power are the main reason for that. Last year, researchers from the University of Texas at Austin found that wind turbines and big solar farms are already the cheapest sources of new electricity generation across much of the country — and they're still getting cheaper. In California, solar is the least expensive option for much of the state.

"The prices for renewables have come down farther and faster than anyone thought was possible," said Sonia Aggarwal, vice president of Energy Innovation, a San Francisco-based policy research group that supports clean energy development.

Increased reliance on solar and wind farms is expected to create new challenges for California, since they only generate electricity when the sun shines or the wind blows. That's already becoming a problem during the middle of the day, when solar farms sometimes generate more electricity than people can use, and in the evening, when solar farms go offline just as people get home from work.

But experts who have studied the transition from fossil fuels to clean energy say California already has most of the tools it needs to solve those problems.

Those tools could include smarter energy management, such as encouraging homes and businesses to shift their electricity use to times of day when solar panels and wind turbines are active. Some of those shifts could be automated. For instance, Aggarwal said California's 3.5 million commercial and multi-family buildings could install pre-heating and pre-cooling technology, which could be programmed to power up when electricity from solar or wind farms floods the grid. Energy prices that vary throughout the day could encourage those buildings to use electricity when the time is right.

"We like to say there are already 3.5 million batteries installed in California," Aggarwal said.

Other tools for getting to 100 percent could include new twists on old technologies, like hydropower plants that are operated so as to complement wind and solar generation, and solar plants that use molten salt or other fluids to store energy for use when the sun goes down. (One such facility, the 110-megawatt Crescent Dunes solar tower, is already operating in Nevada.) California could also incentivize the development of more geothermal plants in the Imperial Valley, which are expensive to build but can generate climate-friendly electricity 24 hours a day.

Then there's Gov. Brown's controversial plan to link California's electric grid with other western states, which could make it easier for utilities here to import cheap wind energy from Wyoming and New Mexico. The plan has divided environmentalists, with supporters saying it's needed to help the state meet its renewable energy goals and detractors saying it might backfire, allowing politically conservative states like Utah and Wyoming to export their coal power to California. Whether or not Brown's grid plan comes to fruition, California is likely to get a big influx of wind from Wyoming.

READ MORE: In Wyoming wind, a conservative billionaire sees California's future

It's unclear how big a role batteries will play in storing solar and wind power for later use, both for homes and for utilities. Right now batteries are still too expensive for widespread use, and experts say California can get to 100 percent without major battery breakthroughs. But if batteries follow the solar industry's cost curve, they could make the transition to clean energy even cheaper.

Jacobson, the Stanford professor, has organized some of his research into the Solutions Project, which provides a state-by-state road map for abandoning fossil fuels and outlines the costs and benefits to each state. For California, he found that transitioning to 100 percent renewable energy would actually lower the cost of electricity, saving the average Californian $161 per year by 2050.

If the cost savings from reducing climate change and hazardous air pollution — most importantly lower healthcare costs — are also taken into account, California would save an average of $7,395 per person by 2050, Jacobson found. About 12,500 fewer people would die each year as a result of air pollution.

"It's a no-brainer," Jacobson said.

Sammy Roth writes about energy and the environment for The Desert Sun. He can be reached at sammy.roth@desertsun.com, (760) 778-4622 and @Sammy_Roth.