Natural gas-fueled appliances such as water heaters and ranges may eventually become the sign of an older home as policymakers push forward with California's ambitious plan to decarbonize the state.
The latest sign of this shift is the pressure facing the California Energy Commission to require developers of new apartments and single-family homes to install only electric home-heating systems, water heaters, ovens, dryers and stoves.
As noted in a recent report from the California Air Resources Board, there are two reasons for banning natural gas-powered appliances: It would cut the state's greenhouse gas emissions by as much as 10 percent while also reducing indoor air pollution blamed for respiratory problems.
But some question the urgency of the campaign, noting natural gas is generally a less expensive way to power appliances, and that using the fuel in homes can be more reliable than switching to exclusive use of electricity, especially at a time of heightened risk of power shutoffs because of wildfires.
The push to electrify home appliances is also a symbolic threat to Kern County's embattled oil industry, which in 2017 produced 70 percent of the state's domestically sourced natural gas.
Local politicians have spoken up against phasing out natural gas, saying that such efforts would raise costs on businesses and consumers. They have instead supported diversification of the state's energy industry as a way of promoting affordability and flexibility in case cyber threats suddenly cut off the flow of electricity.
The energy commission is preparing to draft a report that environmentalists hope will propose barring natural gas appliances in new residences across the state. A final decision on whether to include that measure in the state's master building code is expected next summer.
Earlier this month the air board made its feelings clear by adopting a resolution that it supports a move by the energy commission to ban gas appliances in new homes. The resolution also called for working with regional air districts to reduce emissions of nitrous oxide and other pollutants by electrifying home appliances.
A report by the air board's staff found gas appliances pollution indoor settings with not only nitrous oxides but also carbon monoxide and particulate matter, increasing people's risks of asthma, allergies and respiratory and heart disease.
By the Sierra Club's count, more than three dozen cities or counties in California have adopted ordinances phasing out gas-powered appliances but not necessarily doing away with them altogether.
Kathryn Phillips, director of Sierra Club California, said natural gas is a focus for the organization because it is a greenhouse gas many times more potent than carbon dioxide.
"If we still have every new building and every new home hooking up to gas we'll still be producing an awful lot of … climate pollution," Phillips said. She added that as technology improves, electrification is becoming most cost-efficient.
But there are substantial doubts that electric-powered appliances are less expensive to operate than those powered by natural gas, and that's one reason the building industry has been slow to embrace full electrification.
Dave Dmohowski, executive officer of the Homebuilders Association of Kern County, said he's not convinced complete home electrification is a money-saver, given that natural gas is cheap and efficient and, at this point, gas-power appliances tend to be simpler and more durable than electric ones. He also points out that a large share of California's and the nation's power plants run on natural gas.
Plus, research by the state's building industry suggests consumers prefer gas appliances, especially for cooking, Dmohowski said.
As much as he favors a balanced approach that doesn't rule out any single form of energy, he's also realistic about where policymakers are headed in California.
"Given California's orientation toward clean energy and climate change," he said, "I think it's probably a done deal."
A recent study out of UCLA supports his skepticism. It concluded appliance electrification programs gaining popularity in California might increase consumer costs while having little impact on the state's greenhouse gas emissions.
Part of the reason gas may hold an edge in cost-efficiency, researchers determined, is its relatively low price in the age of hydraulic fracturing, which has opened access to large underground methane deposits. Meanwhile, the study noted, the quick ramping up of utility-scale renewable energy projects has raised the cost of electricity in the state.
"Careful, integrated planning and sequencing of future electrification policies and programs will be necessary to avoid unintended consequences," authors of the UCLA report wrote.
The Southern California Gas Co. said it supports the state's climate goals and noted methane, which is natural gas, already provides some of the power behind electric vehicles.
The company emphasized natural gas increases reliability and resiliency in the state's energy portfolio. It said it is working to decarbonize fuels by investing in renewable natural gas, which can include methane harvested and purified at Central Valley dairies.
An organization that has focused on practical aspects of electrifying residential appliances is National Community Renaissance, a large, Rancho Cucamonga-based nonprofit that develops, operates and maintains affordable housing. Its director of sustainable design, architect Tim Kohut, said water heaters present the toughest part of the challenge, particularly for multi-family residential projects.
Until three years ago, he said, the organization used bulky, expensive solar thermal systems to preheat water for apartment dwellers, as state guidelines require for new multi-family housing projects using natural gas for its water heaters.
Then the nonprofit turned to decentralized, electric heat pumps and found they offer cost parity with natural gas water heaters — and they offer savings by eliminating the need for solar preheating.
There's an additional, if minor benefit from not having to build natural gas infrastructure in every building, Kohut added in an email. Even more money is saved through the installation of rooftop photovoltaic panels.
Now each of the nonprofit's projects currently in design stages is all-electric.
"We made this move because we understand the cost of PV (photovoltaic solar panels), we understand operational economics, and we’re interested in lowering our operational costs as much as possible without impacting first cost," he wrote.