Editor’s noteThis story was funded in part by a grant from Solutions Journalism Network to examine ways Utah businesses and individuals are working to reduce the state’s air pollution problem.

Salt Lake City wants to reduce greenhouse gas emissions and transition to a renewable electricity supply in the next 10 to 20 years.

In order to achieve the first goal and take advantage of clean electricity from the second, the city is encouraging developers to build without natural gas and use all-electric technology for heating and cooling.

“The building sector, not just in Utah but across the country, is one of the largest energy-consuming sectors,” says Peter Nelson, Sustainable Business Program Coordinator for Salt Lake City.

[Read more: An affordable housing experiment in Utah aims to create energy-efficient homes for low-income families]

After an extensive analysis of the barriers and opportunities to transition to all-electric energy for homes and multi-family buildings — including converting existing properties — the city plans to focus on new multi-family construction.

The economics make the most sense, saving $1,600 per unit, according to the analysis. And the environmental impact is potentially large: 91% of residential permits in the city since 2013 were for apartments, according to a University of Utah study.

Salt Lake is one of eight pilot cities working with the Building Electrification Initiative, a national project focused on carbon neutrality and mitigating climate change. Noting that up to 40% of greenhouse gas emissions come from heating buildings, the initiative’s goal is to eliminate their burning of fossil fuels by transitioning from boilers and furnaces to high-efficiency electric air source heat pumps and heat pump water heaters. Unlike typical heating systems, air source heat pumps don’t create heat but instead transfer it by using a refrigerant that absorbs heat from colder air, according to an initiative by Boulder, Colo., which is another BEI city.

Starting last year, BEI created an inventory of Salt Lake City’s residential buildings, interviewed stakeholders including developers and Rocky Mountain Power representatives, and analyzed the economic impact of using the all-electric technology on different housing sectors.

While single-family homes make up more than 80%of the city’s total residential parcels, the report concluded it wouldn’t be economically feasible to convert them to electric: Most would need electric panel upgrades before they could convert to heat pumps, and it could take up to 16 years for the operational savings to cover the cost of the equipment. Plus, energy bills would be higher, since higher rates of electricity use result in a higher rate charged.

In addition, existing owners don’t connect air pollution to buildings “and therefore do not feel empowered or educated to make upgrades to improve their health quality,” according to the report.

“Most people, when they think of air quality, think of tailpipe emissions,” Nelson said. But “whenever you’re combusting natural gas on site, you’re contributing to poor air quality. We definitely want to make that connection” for the public, he said.

By 2024, pollution generated by Utah homes and small businesses will overtake all other pollution sources in the winter, including vehicles and heavy industry, according to the Utah Department of Air Quality. The natural gas combustion that occurs in water heaters and furnaces in homes along the Wasatch Front generates nearly 10 tons per winter day of nitrogen oxides, a precursor to the tiny particles — called particulate matter — that dirty the air during inversions. Throughout the winter, that’s equivalent to the pollution generated by just under one-third of all gas-powered vehicles in the Wasatch Front, says the DAQ.

Using DAQ data, Dominion Energy, which supplies natural gas to Utah, says natural gas contributes just 7% of all of the Wasatch Front’s inversion-causing emissions in the winter, though it hasn’t analyzed what natural gas’ contribution will be as cleaner gasoline and better technology drives down auto emissions.

Still, it says its own improvements in reducing emissions aren’t being taken into account in the discussion of how to clean Utah’s air and mitigate climate change.

“They assume natural gas is business as usual. We absolutely intend to advance technologically to do what we can to lessen our carbon footprint,” says Judd Cook, director of gas operations in Utah, Idaho and Wyoming.

Dominion, a Virginia-based company that provides gas or electric power to 7 million customers in 18 states, is “all in” on reducing greenhouse gas emissions and improving air quality, with a pledge to be net zero on carbon emissions by 2050, he said. The company is the fourth-largest solar company in the world, including investing in about $1 billion in solar assets in southern Utah, according to Dominion. The company is also investing in off-shore wind projects, reducing methane emissions and exploring using its infrastructure to eventually deliver zero-carbon hydrogen. It recently announced a new, voluntary GreenTherm program allowing Utah and Idaho customers to purchase blocks of renewable natural gas—capturing methane (30 times more potent than carbon dioxide) from landfills and agricultural waste—much like Rocky Mountain’s BlueSky program.

Salt Lake City has an agreement with Rocky Mountain for it to provide net 100% renewable electricity by 2030. And while parent company PacifiCorp is reducing its use of coal companywide, the utility’s Utah-based Hunter and Huntington coal-fired plants will continue to be used for another two decades.

Dominion questions the push to electric now, considering that 76% of the state’s electricity supply comes from coal-fired power plants, according to a 2016 report by the Utah Geological Survey, the most recent data available.

Dominion’s analysis shows a 2,500-square-foot, all-electric home in Utah would generate 18 tons of carbon dioxide, compared to a home using a combination of natural gas furnace and water heater, which would generate 14 tons of CO2.

“Right now in the state of Utah, that’s just the case that an all-electric home is going to emit more carbon than an electric-natural gas home,” says Cook. “My question is, why are we doing it?”

But proponents of going all-electric note it would reduce air pollution along the Wasatch Front, since most fossil-fuel burning plants aren’t located in urban areas and it would eliminate the burning of natural gas inside homes.

While electrifying buildings isn’t common in Utah, a handful of local developers have built all-electric buildings. They say construction of all-electric is cheaper because they avoid the costs of gas connections, and the electric equipment takes less space. Rocky Mountain Power offers incentives to existing homeowners and landlords, though the efficient heat pumps must replace existing electric heat sources. The company hopes to offer rebates to customers who want to convert from gas.

The study also found that local contractors are inexperienced with installing heat pumps; the BEI study found about 15 contractors associated with the three major manufacturers. Rocky Mountain said it provides training to distributors and contractors.

Based on the BEI analysis, Salt Lake City plans to continue studying how to get more developers on board over the next several months. Nelson said the city hasn’t determined if it will incentivize or require multifamily developers to go all electric. “We haven’t even gotten into that discussion,” he said.

The study also suggests the city research the differences in indoor air quality between homes with heat pumps compared to gas furnaces; find ways to help low-income residents transition to all-electric; assess and address the gaps in training for contractors and work on energy rates and regulations to advocate for electrification.