A 2013 study in the International Journal of Epidemiology shows children who live in a house with a gas stove are 24% more likely to be diagnosed with asthma over the course of their lives. Credit: azmichelle/Creative Commons

For Chaz Teplin, retrofitting his house away from natural gas is an opportunity to bring his personal life in line with the values underpinning his work as an energy scientist. The 47-year-old Boulder resident is principal of the Carbon-Free Electricity program at Rocky Mountain Institute (RMI), a sustainability research and consulting organization, where he focuses on decarbonizing the electricity sector.

“The route to decarbonization is to electrify everything and clean up the grid,” Teplin says. 

To live up to the green values he espouses at work, Teplin has begun renovating his South Boulder townhouse to run entirely on electricity. He plans to swap out his air conditioner and gas-powered furnace for an electric-powered heat pump; his gas-powered hot water heater will be replaced with an electric model. Teplin is also installing a charging station for his electric car. 

But even with his climate background, Teplin says the electrification process has been challenging. Finding contractors with all-electric building know-how, securing rebates from various sources and paying the construction bills can all be stressful. In total, he expects the entire process to take a few months and cost over $30,000 after rebates. But Teplin says the cost is worth getting his home off natural gas. 

“In my day job, I work on cleaning up the grid. I feel it’s only right to complement this by electrifying,” he says. “Walk the talk, as they say.”

The vast majority of houses in Boulder use natural gas as their main heating source. (Xcel Energy’s energy mix in the state is about 30 percent gas.) City building codes require all new residential construction to meet net-zero emissions by 2031. But while some other municipalities across the country are seeking to begin the process of transitioning away from gas now — through bans on gas hookups in new buildings, for example — those conversations and policy moves have been less overt here.

To help residents who want to follow his lead, Boulder Reporting Lab spoke with Teplin and his RMI colleague Brady Seals about the costs, challenges and advice for moving away from natural gas in your own home.  

Energy scientist Chaz Teplin and his co-workers pose for a photo in their South Boulder townhouse, which Teplin is retrofitting to run entirely on electricity. Courtesy: Chaz Teplin

Consult the pros

Teplin says the biggest obstacle to electrifying residential buildings is finding a company with knowledge and enthusiasm surrounding green construction. Some builders might not be up to speed on the latest all-electric technology, or might incorrectly think natural gas is the only reliable heat source in cold weather.

“There are not many contractors who want to get rid of gas altogether,” Teplin says. “Luckily, in Boulder, there are a few HVAC contractors who do.” 

Teplin says Helio Home and Elephant Energy are two local home-building consulting organizations that offered advice on his electrification project and helped him find quotes from contractors.

In addition to finding the right contractor, Teplin says anyone looking to electrify their home should start planning early.

“The most important thing to do is to think ahead,” he says. Once something breaks, people typically focus on finding the cheapest and quickest replacement. Teplin says the urgency of a broken appliance might lead people to stick with gas if they haven’t done their research on electric heat pumps. “If you wait for your furnace to fail, it’s too late.”

Know the costs

The price tag is another big obstacle. Teplin says his retrofit will cost about $35,000. There are rebates available from EnergySmart, a partnership with local governments including the City of Boulder to provide energy audits and incentives that help offset some of the cost. But Teplin anticipates they will only save him about $3,000. He recognizes the cost of retrofitting is steep and not feasible for many people. 

“The truth is, right now the math doesn’t work out,” he says. “If you’re trying to save, it’s cheaper to stick with gas.”

While retrofitting is often an expensive endeavor, RMI analysis shows building a new, all-electric house in some cities, including Denver, is cheaper than building a new house that runs on natural gas. The analysis estimates up-front costs are $2,700 lower for an all-electric house, and annual utility bills are estimated to be 2% lower than a house that uses gas.

Know the benefits

Brady Seals, a manager with RMI’s Carbon-Free Buildings team, also says the health benefits of all-electric houses help justify the cost of retrofitting. Gas-powered appliances like stoves, furnaces and hot water heaters emit nitrogen dioxide, a greenhouse gas that can be harmful to humans. Nitrogen dioxide irritates the eyes, nose, throat, and respiratory tract, and can cause acute or chronic bronchitis through extended exposure. People with chronic obstructive pulmonary disease (COPD) and young children are particularly vulnerable.

From a health perspective, Seals says switching from a gas stove to an electric induction stove is among the best changes one can make in their house. A 2013 study in the International Journal of Epidemiology shows children who live in a house with a gas stove are 24% more likely to be diagnosed with asthma over the course of their lives.

Seals also cited an RMI study showing homes with gas stoves have nitrogen dioxide concentrations 50% to 400% higher than homes with electric stoves.

Understanding heat pumps

An electric heat pump system is an energy-efficient replacement for a gas-powered furnace and air conditioner. Heat pumps can use air, water or geothermal energy as their heat source. Air-source heat pumps, the most common type, warm a house using the heat pulled from outside air. They can also cool a house by pumping heat from inside the house to the outside. Water-source or geothermal heat pumps do the same thing, but use a nearby body of water or the ground, respectively, to heat or cool the house.

“For most places in Colorado looking to retrofit, I’m pretty sure that [an] air-source [heat pump] is the best option by far,” Teplin says.

Teplin says heat pumps are not as prevalent as they should be in part because of bad information.

“There’s a lot of confusion about what heat pumps are capable of. A lot of the contractors don’t trust them, and think they don’t work at cold temperatures,” he says. “This is a result of both misinformation and outdated information. People have old memories of poor quality heat pumps. The new technology is much quieter and works better.”

Seals recommends Carbon Switch’s guide to heat pumps for potential buyers.

Final takeaways

In addition to harmful health effects inside the house, nitrogen dioxide emissions affect outdoor air quality and contribute to warming the planet. Once the nitrogen dioxide is vented outside of the home, it mixes with oxygen and sunlight to produce ozone and particulate matter. This drives poor air quality, which can cause various health problems. In an area like Boulder already vulnerable to poor air quality from wildfire smoke, house emissions only make the problem worse.

Still, as Teplin emphasized, replacing old appliances with new, all-electric models isn’t cheap, and the costs tend to multiply. Seals says installing a new induction stove, for example, may require additional renovation like an upgraded electrical panel or a ducted range hood.

And despite the environmental benefits, recent polling suggests many people in the U.S. won’t be switching away from their gas stoves anytime soon.

“People love what they know and what they have,” Seals says. But as more and more people understand the environmental and health impacts of gas appliances, she hopes the demand for all-electric appliances will grow.