Less than 2 percent of U.S. electricity comes from the sun. But last week, on a cool Sunday afternoon when there was plenty of sunlight and no need for air conditioning, the bulk of California briefly got 50 percent of its electricity from solar power.
It was a record for the Golden State, and it wasn’t the only one. The next day, more than 10,400 megawatts of solar power hummed along simultaneously on California’s main power grid — 500 megawatts above the previous record, which was set last summer.
The world’s sixth-largest economy kept building sprawling solar farms and installing rooftop panels during the first year of the Trump administration, despite the president’s efforts to support dirtier energy sources like coal. But the people responsible for keeping the lights on say California’s growing reliance on solar is starting to become a problem.
The question they’re asking: Does California have more solar power than it can handle?
It’s not a theoretical question. California already pays solar plants to cut back production on some afternoons, to stop them from flooding the grid with too much electricity. Then in the evening, it’s the opposite problem: People get home from work and turn on their lights, televisions and other appliances just as all that solar power disappears, forcing utilities to fire up costly, polluting gas plants to meet the so-called “evening ramp.”
Companies are under increasing pressure to close those gas-fired power plants, which produce more than a third of the state’s electricity but pollute the air in many low-income communities, and also contribute to climate change. Just last week, NRG Energy said it will retire three gas-fired power plants in Southern California by the end of the year.
“As we retire plants in California, it’s going to be more difficult to meet that ramp” in the evenings, said Stephen Berberich, president of the California Independent System Operator, a quasi-governmental nonprofit that oversees four-fifths of the state’s power grid. “At some point, we’re going to have a tough time meeting that ramp, particularly if we continue with a high solar portfolio.”
Batteries that can store solar power for the evening are getting cheaper, but they still haven’t gotten cheap enough to take off in the way that solar has over the last decade.
Berberich sees at least a partial solution in the state Legislature.
Assemblymember Chris Holden, a Pasadena Democrat, introduced a new version of a bill last week that would help California share energy with other western states. Holden’s legislation would create a regional energy market, into which the Golden State could bid its excess solar power rather than paying plants to cut back. California could also replace some of its polluting gas plants by buying cheap renewable energy from other states, such as Wyoming wind power, that’s available when the sun goes down here.
Supporters of Holden’s bill see a natural partnership with Oregon and Washington, which have big dams with lots of untapped hydropower potential. California, they say, could use those hydropower plants sort of like a battery, selling excess solar power to Oregon and Washington so they don’t have to release water through the dams to generate electricity, then paying them to release it when California needs power.
“When we have these evening ramps that are really steep, they could turn around and provide that hydro for us. That’s the way that regional collaboration could really work,” said Berberich, who oversees the California power grid that set solar records last week.
It sounds simple, but the regional energy plan is highly controversial and was defeated in the Legislature the last two years despite support from Gov. Jerry Brown.
To create the regional market, California would need to give up sole control of its grid operator and share oversight with any other states whose power companies choose to join. Critics worry that conservative officials in states like Utah and Wyoming would force California to import their coal-fired electricity, undermining the Golden State’s clean energy goals and leading to an increase in climate change pollution. The Trump administration would also need to approve the regional market, and could potentially undermine measures adopted by California to shield itself from out-of-state coal.
Supporters of a regional market say efforts by the Trump administration or other states to interfere with California’s energy policies would be unlikely to hold up in court. They also say it isn’t likely to come to that. Kellie Smith, the consultant for the state Assembly’s energy committee who wrote Holden’s bill, said outside interference is “the absolute most remote possibility.” But just in case, she included a provision that would allow California utility companies to exit the new regional market if they weren’t allowed to penalize dirty out-of-state energy sources — a sort of nuclear option, since it would leave California without an electricity market and upend two decades of state policy.
“We really would pull out. In a heartbeat we would,” Smith said. “I think the chance of that happening — it’s like a fraction of a percent.”
Critics, though, worry other states are ready for a fight. Utah lawmakers approved $1.65 million last week for a possible lawsuit against California over its rules that increase the cost of imported coal power, which some Utah officials say are unfair to the state’s coal industry. Utah’s actions “raise the risk that regionalization could put California’s climate policies in the crosshairs,” said Matthew Freedman, a staff attorney at the Utility Reform Network, a San Francisco-based watchdog group that opposes a regional market.
Gov. Brown originally proposed a merger between the main California power grid and PacifiCorp, a Warren Buffett-owned utility with customers in six states, including Utah and Wyoming. That plan was criticized by top lawmakers and some environmentalists due to PacifCorp’s reliance on coal. This year, supporters of Holden’s bill are talking up the benefits of a regional market that starts with Oregon and Washington, states that share California’s commitment to fighting climate change, and possibly also Nevada.
A study commissioned by the California Independent System Operator found that an energy market covering most of the West could lead to $1.5 billion in annual savings for Californians by 2030, and a 3 to 4 percent decrease in regional climate pollution.
But some opponents of a regional market say there are better, cheaper ways for California to keep the lights on while still going big on intermittent solar power.
Craig Lewis is executive director of the Clean Coalition, an advocacy group focused on small-scale “distributed” clean energy solutions. Lewis is worried a regional market would lead to the construction of multi-billion-dollar power lines to carry energy from the interior West to the coast, and that Californians would be forced to pay the price.
Lewis said the state could clean up its energy supply without the risks of a regional market by focusing on rooftop and community-level solar installations, battery storage, and emerging technologies that make it easier for people to use energy when there’s clean power available on the grid. Current policy, he said, puts those kinds of small-scale clean energy sources at a disadvantage by forcing homes and businesses to pay for long-distance power lines even if they’re getting their energy from a local source.
Rather than look to other states for energy, Lewis said, the California grid operator should change its “transmission access charge” formula so that homes and businesses aren’t paying power-line fees when they use electricity that’s generated locally. That would make it easier for customers of Southern California Edison, Pacific Gas & Electric and San Diego Gas & Electric to generate and store their own power, Lewis said.
“Local renewables are essentially getting stolen from to pay for the transmission grid,” he said. If California starts a regional market without fixing the transmission charge issue, he added, “this market distortion (is) going to persist, and it’s going to get worse.”
Lewis said California can get some of the benefits of a regional market without actually giving up sole control of its grid. He pointed to the California-led “energy imbalance market,” a more limited power-sharing program that covers parts of eights western states and could eventually include customers in Canada and Mexico. The California grid operators says the program has saved its participants $288 million since 2014, and avoided the climate pollution equivalent of putting 47,000 cars on the road for a year.
“The energy imbalance market is working very effectively and can easily be extended and enhanced. So that’s an approach that’s really simple to do, and there’s no risk at all at losing any kind of sovereignty,” Lewis said.
But other experts say there’s no substitute for a full-fledged regional energy market, especially as California adds more solar power. Berberich pointed out that the state set another solar-related record last week: its biggest-ever evening ramp. Between falling solar power and rising evening demand on Sunday, utility companies were forced to add more than 14,700 megawatts of power over a three-hour period. That’s equivalent to seven Diablo Canyons, California’s last nuclear plant, which is slated to close in 2025.
“We’re going to have to manage this,” said Smith, who wrote the regional market bill. “We do see that this expansion across the West is the most cost effective way to do so.”