Oliver Ta dribbles some chocolate chips into a pot and begins stirring. The engineer with Southern California Edison, the state's largest electricity supplier, is demonstrating the latest induction cooktop, which heats pots and pans with an oscillating magnetic field.
Sure it's more energy efficient and precise than a gas range, he says. But there's another reason Californians should make the switch now: natural gas is much dirtier than many people realize. And one day, cooking with gas could become as obsolete as cooking with wood.
"Because we're not burning gas," Ta says, pointing to the electric range, "we're not creating any additional greenhouse gases."
That's why a growing number of California cities are banning natural gas hookups, and forcing residents to switch eventually to electric.
In July, Berkeley became the first city in the U.S. to ban natural gas from all new building construction. And in September, San Jose — the 10th most populous U.S. city — enacted a similar measure. Now, more than 50 other cities and counties are considering following suit.
"There was a time natural gas considered cleaner alternative to dirtier sources such as coal," says Drew Johnstone, a sustainability analyst with the City of Santa Monica.
But these days in his city, Johnstone says, natural gas from buildings — composed of more than 90 per cent methane — has become the second largest source of emissions after vehicles. And nationally, according to the Environmental Protection Agency, residential and commercial buildings account for about 12 per cent of U.S. greenhouse gas emissions.
"Methane, when released in the atmosphere, is 84 times more potent [a] greenhouse gas than carbon dioxide," Johnstone says.
Ironically, California still generates much of its electricity — 41 per cent — by burning natural gas. But a growing amount — 34 per cent — is generated from renewable sources.
And some cities like Santa Monica are making renewable electricity the default option. As of February, residents will have to opt out of the more expensive renewable-energy tier, and so far relatively few have.
"We've implemented a renewable energy program where 90 per cent of our homes and businesses are on 100 per cent green power," Johnstone says.
At a recent Santa Monica city council meeting, Johnstone presented the case for adopting measures to offer incentives to encourage electrification and regulate the use of natural gas.
Gerry Rubin was one of several Santa Monica residents who took to the microphone to lobby his councillors for action.
"Other than Donald Trump and a few other climate change deniers, we all understand the urgency here: I don't think we have a choice, not if we're going to be a real true progressive sustainable city," Rubin says. "We have to do this."
In the end, the City of Santa Monica didn't opt for a Berkeley-style ban. Instead, for now it will take a carrot-and-stick approach. New construction with gas infrastructure will be held to a higher energy efficiency standard, while all-electric buildings will only have to satisfy the state's lower baseline code.
"In addition, the city council also directed staff to explore ways to disincentivize building with gas, such as a carbon impact fee," Johnstone says.
He added that that the city's "not going to be pulling gas stoves out of homes anytime soon."
Still, some Santa Monica residents feel the city is going too far.
"You'll continue on with your social engineering and taking away the residents' freedom of choice," Denise Barton told city council.
Barton has at least one powerful ally: Donald Trump. The U.S. is the largest natural gas producer in the world, and Trump has long been an advocate for the resource. In a May press release, his administration termed it "freedom gas."
Trump also has a long record of using the word "hoax" to describe climate change, which is why activists like the Sierra Club's Carlo De La Cruz say it's so important that cities fill the void.
"In the absence of any federal action, we are seeing local leaders — both cities and states — stepping up to really show what climate leadership looks like," De La Cruz says. "Fortunately for us, many of our most important and critical energy decisions happen at the city and the state level."
Given that many cities have announced ambitious climate change goals — Los Angeles, for example, has committed to net zero carbon emissions by 2050 — De La Cruz believes limiting natural gas is the only way cities will meet them.
"Already, emissions that come from gas are already larger than all of our power plants combined," De La Cruz says. "Building new buildings without a gas hookup is actually cheaper and more cost effective than it would be to install those gas lines and to introduce a dirty, dangerous and risky fuel into buildings that quite frankly don't need it."
Leaks are also a growing problem. According to a study in the journal Science, methane emissions from U.S. oil and gas operations are at 2.3 per cent of total production per year, enough natural gas to fuel 10 million homes each year. And then there are the catastrophic leaks.
In 2015, more than 100,000 tonnes of natural gas spewed from the Aliso Canyon storage facility in Los Angeles County.
"We had the second largest environmental catastrophe in the United States after the Deepwater Horizon," says Los Angeles County's sustainability officer Gary Gero. "More methane spilled out of the gas storage facility here in Los Angeles County than anywhere in the world. So we're really sensitive to issues around natural gas."
Now L.A. County's board of supervisors has directed Gero to come up with measures to limit natural gas for the million residents under the county's supervision.
"If we can phase it out and protect our neighbourhoods, all the better," Gero says.
"So when Berkeley took that the first big bold action, the rest of us said it's possible … it's not something that we have to wait five years to do. We can actually start to implement these strategies today."