Solar energy:
California uses more than any other state, but demand surges — and the grid lacks storage to bridge the gap.
As a heat wave blisters California, demand soars for power to cool the millions sheltering at home. But the air conditioners go on just as the sun starts to drop in the sky — and solar power, one of California’s largest renewable energy sources, starts to wane.
How much that dependence on renewable energy has to do with the present blackouts is up for debate.
Steven Sexton, a fellow in the Energy Initiative at Duke University, explained that when demand for power spikes, the state needs an energy source that is “dispatchable” — something that can be turned on to meet that demand. Without storage, renewable energy lacks that capacity.
“The benefit of the renewable supply is that it’s clean,” he said, “but the downside is that it can’t be dispatched by a grid operator” like the California Independent System Operator, the nonprofit that runs the grid but doesn’t own the electricity that flows through it.
As California turns to more renewable energy, gas plants are used less often, Sexton noted, which means that they generate less revenue.
This in turn means that they are more costly to operate, and that there are fewer of them to call upon when energy is needed.
But experts in the solar industry say that renewable energy may be ameliorating the blackout problem.
There are two different types of solar energy: the kind that comes from large solar power plants in California’s deserts, and the kind that comes from solar panels on rooftops and smaller, private properties. Rooftop solar is considered “behind the meter,” which means it isn’t counted by grid operators, Bernadette Del Chiaro, executive director of California Solar and Storage Association, explained.
“If we did not have a millionplus rooftop solar systems on all of those homes, businesses and schools throughout California this past weekend, the strain and stress on the electric grid would have been even worse,” she said.
Del Chiaro said that better storage for solar energy is the key to preventing the problem of power blackouts in the future. If everyone had a solar power battery, she said, they could switch to that as the sun sets, relieving pressure on the power grid. The technology for this is there, she said — a battery to store solar power is the same as the battery in an electric car.
But producing that solar storage is costly.
“It’s certainly the case that battery storage, while it’s advancing and costs are declining, is still far more costly to provide that kind of backup generation than to provide backup generation from gas plants that are already built and serving the grid,” Sexton said.
Right now, adding a battery charged by solar to your home would cost a consumer anywhere from $10,000 to $12,000, according to Del Chiaro. With both federal and state government tax credits and rebates, consumers could get around 50% off of that cost, she said, but that’s still $5,000 to $6,000 in outofpocket costs.
Gov. Gavin Newsom also pointed to storage as a problem Monday. While he stressed the importance of moving forward toward more clean energy, he said that in the transition away from “polluting fossil fuels,” there are gaps in the “reliability” of power, he said in a news conference.
“Our capacity for storage in particular ... substantially needs to be improved,” Newsom said, “but I am confident in our capacity to deal with that.”
Danielle Mills, director of the American Wind Energy Association, said that, in addition to storage, diversifying California’s electricity system — turning to energy sources like wind or renewable imports — can help alleviate the reliability problems that come with the transition.
“Our system right now is almost entirely dependent on solar storage and gas, so if we’re thinking through how to transition to 100% clean energy, we do need to think about those additional resources,” she said. “If we want to rely on solar and other renewables, we really need to find a way to get them all to work really well together.”
Sexton agreed that in an ideal world, California could rely exclusively on renewable energy. But the pain points in that transition are economic.
“Californians are paying among the highest prices for electricity, and they can’t expect it to always be on,” Sexton said. “Certainly, the goals of the governor, his predecessor and the (Public Utilities Commission) are virtuous and noble ones, but there are some practical realities that I think California will confront as a push for increasingly aggressive clean energy standards.”
But some say that the problem isn’t with renewable energy at all.
Michael Wara, director of Stanford University’s climate and energy policy program, said he’s not convinced that solar or wind power is a direct cause of the rolling blackouts. He noted that the energy shortage has been arising in the early evening hours, just as the grid would be expected to tap into nonsolar energy sources.
“It’s not clear to me at all that this had anything to do with renewable energy,” Wara said. “The timing suggests problems with gas plants ... because they are a fillin for solar as the sun sets. Something about that system didn’t work.”
California Independent System Operator CEO Steve Berberich agreed in Monday press call that “renewables are really not a factor” driving the blackouts, citing the need for better storage, like Newsom and Del Chiaro.
“It’s simply a matter of raw capacity,” he said, calling for “an overbuild of renewables and a fairly extensive deployment of batteries.”
The pressure on state regulators to move forward with renewable energy storage, despite its costs, is increasing as the power blackouts continue. A coalition of consumer groups, environmentalists, school officials and business groups are calling on the governor and state legislature to pass AB1001, the School Disaster Resiliency Act, authored by Assembly member Phil Ting, DSan Francisco, which would equip 2,000 schools with solar-charged batteries.
Funding would come from a revenue bond that would be repaid over time through school energy bill savings, according to the coalition.
“It’s elementary,” Dan Jacobson, state director for Environment California said. “Any thirdgrader can tell you that we need more solar power, not less, and we need more batteries to store that sunshine for use after the sun goes down.”
“These heat waves are going to keep happening with climate change,” Del Chiaro said. “So, let’s do more instate renewable energy and renewably charged batteries ... let’s build a smarter grid that’s flexible to these kinds of events, and let’s solve climate change and reduce air pollution at the same time.”