When it comes to how we power our homes and appliances, it turns out “Think globally, act locally” could actually impact our carbon footprint. Electrifying our homes by choosing electric appliances instead of those powered by fossil fuels enables meaningful reductions.

That’s why new incentives at federal and state levels are encouraging consumers to switch from natural gas, propane and oil to electricity for heating and cooling (HVAC) equipment, stoves, dryers and water heaters. For electrical contractors working with homeowners and landlords making this switch, there are ways to ease this transition, even when panel capacity might seem insufficient.

Why now?

Residential energy use accounts for approximately 20% of U.S. greenhouse gas (GHG) emissions—equivalent to those produced by Brazil and larger than Germany’s production, according to 2020 research from scientists at the National Renewable Energy Laboratory (NREL). The sources of those emissions are pretty easy to track. In addition to what’s produced by local electric utilities’ power generation, they include the emissions related to the natural gas, propane and oil used by many homes’ appliances. 

Switching to electric options could go a long way to reducing the GHG contributions of U.S. single- and multifamily homes, regardless of how that electricity is produced. For a report released in February, NREL analysts modeled the entire U.S. housing stock and found that moving to heat pumps from other HVAC technologies cut emissions in all 48 contiguous U.S. states over the equipment’s projected 16-year lifespan. 

Analysts modeled multiple scenarios ranging from 50% carbon-free electricity by 2035 to 95% by the same year, and emissions dropped between 36% and 64%, depending on power supply and heat pump efficiency. This is because heat pumps are much more efficient than even the most miserly natural gas furnace or air conditioning condenser. Additionally, simply by reducing natural gas demand, related methane leaks that can plague local gas distribution systems also decrease.

Figure 1: Currently, U.S. home electrification is highly regional. Big opportunities exist in northern and Midwestern states to move residential appliances away from natural gas. Courtesy of the U.S. Energy Information Administration.

Who’s leading the charge?

Some U.S. regions are already fully electrified or close to it. As the map in Figure 1 illustrates, states in the Southeast lead the country in electrification, with more than 75% of homes in Florida depending entirely on electricity.

“Whole-home electrification is much more common in areas with mild or hot climates, due to the moderate heating load when compared with northern climates,” said Cavan Merski, a data analyst with Pecan Street, an Austin, Texas-based nonprofit focused on consumer adoption of climate-friendly technologies. 

However, he added that heat pumps in northern regions can still bring down emissions when the existing electric resistance heaters and inefficient air conditioners are replaced.

“Two-way heat pumps for both space and water heating are much more economical than resistance heat and are now replacing the resistance units, as well as natural gas-powered furnaces and water heaters,” Merski continued. “This conversion is still most feasible in climates with mild winters, but adoption is increasing in northern climates.”

Sean Armstrong, partner and managing principal with Redwood Energy, Arcata, Calif., a design engineering firm focused on all-­electric residential construction, said colder U.S. regions are becoming strong markets for heat pumps as homeowners and landlords seek to break ties with more expensive fossil fuels.

“Oil boilers and propane systems are the easiest to make a cost-effective argument for replacement—usually they’re about the same cost, and a heat pump air conditioner is only, maybe, 10% more expensive” than a traditional unit, he said. “So, we’re seeing a lot of electrification in the Northeast because people hate those oil boilers.”

Little by little

Most consumers aren’t going to fully electrify their homes in a single move unless they’re undertaking a major renovation project. Instead, they are more likely to shift one appliance or system at a time, as equipment needs replacing. As Figure 2 shows, dryers are the most common electric appliance in U.S. homes, and they are likely to be the entry point for consumers looking to move away from natural gas. Merski said these are also among the easiest to install.

“From an electrical standpoint, I think dryers, stoves and water heaters require the least amount of work,” he said. “This will typically involve installing a larger circuit to serve the appliance than its natural gas counterpart required. Some newer energy codes that have been recently adopted require homes to be electric-ready and include these circuits, so this step wouldn’t even be necessary.”

Stepping up from dryers, stoves (and stand-alone ovens and cooktops) are the next most common electric appliances in U.S. homes. As with dryers, moving from natural gas or propane to electric will likely trigger the need for a new 240V outlet and a 40A or 50A circuit, unless an electric version was previously installed. 

The hot-button issue of indoor pollution from gas ranges has drawn increased interest in electric cooking options, especially induction products. While natural gas backers have successfully positioned their appliances as the choice of selective home chefs, Armstrong said induction burners offer equivalent or better performance and added safety benefits. Induction burners, which operate using magnetic fields, only turn on when they sense a compatible pan, and they also have a lower high-temperature limit, which can reduce the fire risk.

“Induction burners only get to 475ºF, whereas an electric resistance burner can get to 1,400ºF, and gas gets to 3,400ºF, where you can easily melt aluminum pans and light the house on fire,” Armstrong said, noting the added safety appeal in multifamily developments. 

“I see it in apartment complexes all the time, as people try to move toward safer stoves, because apartment complex fires are terribly dangerous for everybody,” he said.

Figure 2: Consumers are most likely to have an electric dryer in their homes, while space heating remains primarily supported by natural gas, propane or oil. Courtesy of the U.S. Energy Information Administration.

Capacity questions

Of course, the higher power demand that comes with this electrification can begin to stretch a home’s capacity. Currently, 48 million of the nation’s 86 million single-­family homes run with electrical panels under 200A, according to Pecan Street research from 2021, with many at the 100A level required as a minimum by the National Electrical Code. Squeezing multiple electric appliances in at this service level can be challenging, especially if an electric vehicle charger is included or planned. 

“The bigger the load required, the more likely it is to trigger a need for a service upgrade—within each load, however, there are different sizing considerations,” Merski said. “For example, EVs can charge on moderately sized circuits to avoid an upgrade if that suits the customer. This flexibility is very important to expanding adoption quickly.”

This is an issue Armstrong has run up against in Redwood Energy’s work with multifamily properties in California. His company specializes in engineering for affordable, net-zero and net-zero-ready multifamily housing. While the group can design efficiency into its new-construction projects and wire them for all current and future needs, its renovation jobs can require creative solutions to stay within existing electrical service limits. 

A new option is an induction range manufactured with its own battery system—Armstrong says the company is deploying 36 for evaluation at an apartment retrofit project where rewiring could become complicated. However, this won’t work for everyone, given the added weight of the batteries and a price tag of $6,000. 

But of all the electric appliances and alternatives above, an EV charger is the most likely to push an existing panel past its 100A limit, Merski said, noting this is an upgrade many will need to make if we’re to reduce transportation’s contribution to further climate challenges. 

“By far the biggest reduction in GHG emissions would be buying an electric vehicle, though emissions will vary depending on the electricity generation source on the grid the customer is connected to,” he said. 

Electrical contractors can explore multiple options to help home-electrification customers stay below 100A. Armstrong is a fan of smart electrical panels. He sees them as especially helpful in multifamily renovation projects, where the service to individual apartments can be significantly below 100A. 

Smart panels are really more like home energy-management systems and provide on-the-go, app-based control of individual circuits. Using apps, residents can rank circuits so that, for example, the dryer takes priority over an EV charger on laundry day. Then, once drying is done, the charger can ramp back up again automatically.

These panels can cost less than a full service upgrade—which may involve the local utility having to replace the existing line to the home, along with the meter—but they’re still expensive. For example, the San Francisco startup Span has received a lot of press recently for its high-tech panels, but they’re priced at $3,500 each, not including installation costs. 

As an alternative, individual circuits can be equipped with smart splitters to accomplish the same task. Not all local authorities allow the devices, but where permitted, they can provide similar functionality at the individual circuit level for $300 to $400 each (plus installation).

“Load shifting and management could completely transform the upgrade scenario, particularly in respect to the EV charger,” Merski said. “Our data show people charge at home frequently, which means they can usually flex this load within 12 hours. That flexibility can allow EV charging to avoid other loads in the home, generally in the overnight hours, while still being fully charged when the vehicle would be needed in the morning.”