MARY LOUISE KELLY, HOST:
California has become the first state in the country to require that all new houses have solar panels. The mandate is aimed at reducing California's overall greenhouse gas emissions. That could be considered a stretch goal as Emily Guerin of member station KPCC reports.
EMILY GUERIN, BYLINE: Kirk Nason lives two blocks from the ocean in Huntington Beach, Calif., in a house that is totally decked out with energy-saving technology. He was even wearing a Tesla T-shirt.
KIRK NASON: I'm a firm believer that we're messing up the planet.
GUERIN: But back when he bought the house in 2006, it didn't have any of that.
NASON: No, I was probably one of the first people in Huntington to get solar.
GUERIN: But if you were to buy that same house brand-new in just a couple of years, it would come decked with solar panels. That's because the California Energy Commission recently voted to make them mandatory on all new single-family homes and small apartment buildings beginning in 2020. It's a really big deal, especially for solar installers like Sunrun.
ANNE HOSKINS: So this is potentially doubling the market in California, which is already the largest market.
GUERIN: That's Anne Hoskins, Sunrun's chief policy officer. The company doesn't do a ton of work right now on new homes, but this mandate will change that. And Hoskins thinks it might mean more installations on existing homes, too.
HOSKINS: It makes the point very strongly that solar on a rooftop is a standard part of what you would want in a house.
GUERIN: But adding solar panels to new homes also makes them more expensive - about $10,000 more per house. This in a state where the median home price is already over half a million dollars. Still, solar proponents say new homeowners will pay off the cost of the panels in less than 10 years. Ethan Elkind is with the UC Berkeley Law School's climate program.
ETHAN ELKIND: Every time a homeowner has solar on their roofs, that means that they're not going to be needing as much electricity from the grid.
GUERIN: He says buying less power from the grid means saving more money. That's certainly been Kirk Nason's experience. His solar panels produce more power than he can use, so he sells it to his utility, Southern California Edison.
NASON: I actually have a negative electric bill, so I get money back from Edison.
GUERIN: Up to $40 a month. That's part of why Nason is a big fan of the new solar mandate.
NASON: I think it's a no-brainer.
GUERIN: The new mandate doesn't make existing houses in California get solar, though, just the 80,000 or so new houses built every year, which means it won't actually do that much to reduce the state's greenhouse gas emissions. Still, Ethan Elkind says every little bit helps, especially because California is trying to cut its emissions dramatically by the year 2030.
ELKIND: Twenty percent of the greenhouse gas emissions in California come from electricity production. So if we can start reducing the emissions associated with electricity, that's going to make a pretty sizable chunk of our goals.
GUERIN: But in California, like in many states, cars and trucks are responsible for the bulk of climate pollution - about 40 percent, or twice as much as electricity generation.
ALEX STEFFEN: Until we tackle that problem, requiring solar panels on new construction is really just a Band-Aid.
GUERIN: That's Alex Steffen, a self-described planetary futurist, the kind of job description that could only exist in California. He says the only rational policy on climate for the state would come in three parts - reduce driving, reduce driving and reduce driving. For NPR News, I'm Emily Guerin in Huntington Beach, Calif.
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