The New York Times
April 5, 2019
By Jill Cowan

How Californians get power has been in the news a lot lately, between Pacific Gas & Electric’s woes and Mayor Eric Garcetti’s recent announcement that the Los Angeles Department of Water and Power would phase out three natural gas power plants on its way toward 100 percent renewable energy sources.

“We have an obligation to end dependence on fossil fuels, embrace the technologies of tomorrow, and prioritize renewable energy,” Mr. Garcetti said in a statement to The Times this week.

The question now is how to do that.

Today, the residential solar power provider Sunrun released a report with what its leaders said could be the answer: a mass deployment of residential solar panels, along with batteries, that collectively form a kind of virtual power plant operated by a utility.

“If one of the challenges is that we want to decommission three of these gas plants, we believe that with rooftop solar and storage, we could pretty easily replace one of them by 2030,” said Lynn Jurich, Sunrun’s chief executive and co-founder.

According to the report, although L.A. already has 36,000 homes with rooftop solar units, as a percentage, it’s fractional: 2.5 percent of residential customers, compared with San Diego’s 11 percent, or 139,000 homeowners.

Expanding L.A.’s total to 75,000 homes and apartment buildings, with batteries, could provide enough power to replace one of the retiring plants and cost $60 million less, the report says.

The batteries, Ms. Jurich said, would give customers a backup power source when it’s less sunny, addressing a primary concern about solar.

[Read about Sunrun’s challenge to Tesla.]

The report suggests a virtual power plant could also counter another concern about residential solar power: that upfront costs make it too expensive for many would-be customers.

“You can contract with the utility, so you can use that credit,” she said.

Sunrun, however, has an interest in promoting solar power. So how realistic is its suggestion?

I put that question to Bill Powers, an engineer in San Diego who serves as an expert witness on behalf of consumers before utility regulators across the country.

“What Sunrun is proposing is absolutely doable — it is the future and it will happen,” he told me. From a technological and cost standpoint, it would be straightforward to make the transition.

“The problem,” he said, “is that it is so diametrically counter to the way investor-owned utilities and even large publicly owned utilities have made money and done business historically.”

But, Mr. Powers said, as pushback against the investor-owned Pacific Gas & Electric has built up, large-scale solar power in L.A. could be a model for cities like San Francisco, which is exploring creating city-owned utilities.

“What’s happening in the state is a general grass-roots fatigue with investor-owned utilities,” he said.

Aura Vasquez, a commissioner for the Los Angeles Department of Water and Power, said she thought that, ultimately, rooftop solar will be a big, cost-effective source of the city’s power in the future. But getting there will be the tough part.

“Staff are excited and they want to do it,” she said, “but I don’t know if we really have the knowledge.”