Renewable power goal needs new technology
In the past decade, California has tripled its use of renewable power, raising wind turbines above hills and plugging vast fields of solar panels into the grid. That may have been the easy part. California legislators now want the state to get 100 percent of its electricity from carbonfree sources by 2045, sending Gov. Jerry Brown a bill to sign that would lock in that goal. The threat posed by global warming, they say, demands no less.
But getting to 100 percent will take more than simply ramping up California’s existing efforts.
Reaching the goal will require more solar plants and wind farms. But it will also depend on developing better, cheaper ways to store large amounts of energy, either by perfecting
existing technology or developing new forms.
It could also mean making better use of the renewable power California generates, for example by persuading drivers to buy electric cars and charge them in the middle of the day, when solar power floods the grid. It could also mean more tightly integrating California’s energy market and grid with those in neighboring states.
“It’s not feasible, cost-effectively, with the technologies we have now,” said UC Berkeley energy economist Severin Borenstein. “But 2045 is 27 years from now, and we’re going to develop a lot of new technologies between now and then. And I think that’s what this bill is designed to do.”
California has set ambitious goals for slashing its greenhouse gas emissions 40 percent by 2030 and this month will host a summit to coordinate international efforts on global warming, despite antipathy from the Trump administration. But the state is already bumping up against some of the issues it must resolve to reach 100 percent clean power.
The state’s solar plants, for example, often pump out more electricity at midday than the grid needs. California still relies on natural gas power plants to supply electricity in the morning and evening, as the sun sets. But low wholesale electricity prices, caused in part by that daily flood of solar production, are making many of them uneconomical to run.
“There really isn’t a technology that’s cost-effective that can replace them right now — period,” said Jan Smutny-Jones, chief executive officer of the Independent Energy Producers Association.
His trade group represents companies that operate conventional power plants as well as owners of solar and wind facilities. Smutny-Jones worries that natural gas plants in the state may be forced out of business while the state still needs them. Many clean-power advocates hope advanced batteries will replace those plants, but that isn’t possible yet, he said.
“I’m a big believer in batteries, but there’s a danger in overhyping what they can do and how fast they can do it,” Smutny-Jones said. “If this was an easy problem, it would have been solved by now.”
Not everyone agrees.
J.B. Straubel, chief technical officer of electric automaker Tesla, said the substitution process is already starting. The Palo Alto company has installed banks of its Powerpack batteries to support grid operations in California, Hawaii, Australia and elsewhere and recently announced a similar project with Pacific Gas and Electric Co. at Moss Landing (Monterey County).
“My feeling is we can compete very effectively — we are competing today,” Straubel said. “It’s already clear today that it’s vastly easier and faster to get permitted and deployed a battery project than a natural gas peaker plant.”
Recognizing the challenges ahead, the bill passed by the Legislature last week, SB100, does include some wiggle room.
For example, the bill does not mention penalties for missing the 100 percent target (though it does for an interim goal of 60 percent renewables by 2030).
And while the current renewable program does not count large hydroelectric dams, they would count toward the 100 percent goal. The bill, in fact, calls for 100 percent of electricity to come from renewables “and zero-carbon resources,” a clause that would include nuclear power if California’s last nuclear plant weren’t scheduled to close by 2025.
“The 100 percent is a goal, not a mandate,” said Laura Wisland, a senior energy analyst with the Union of Concerned Scientists research and advocacy group.
California’s shift toward renewable power has, so far, been swift.
Ten years ago, renewables provided 10.6 percent of the state’s electricity, excluding large hydroelectric dams. Solar supplied less than half of 1 percent, according to the California Energy Commission. Last year, in contrast, solar alone accounted for more than 10 percent, while renewable sources as a whole provided 29 percent of the state’s electricity. Large dams kicked in another 14.7 percent.
“We’re already pretty far down this path,” Wisland said.
Reaching 100 percent could require some sources the state has not yet tapped.
Stanford University Professor Mark Jacobson, who has modeled ways to supply all of the state’s energy needs with renewables, points to floating offshore wind turbines as one emerging technology that could help. Winds off the California coast tend to be more consistent than on land, and they typically peak, he said, around 4 p.m., as solar production is falling. Floating turbines can be located far enough from shore that they don’t interfere with shipping — or ruin the seascape vistas cherished by Californians.
“There are all sorts of things,” Jacobson said, “that can and will be done.”