Chart: Here’s how the US could get heat pumps in every home by 2050

Canary Media’s chart of the week translates crucial data about the clean energy transition into a visual format. 

To decarbonize the U.S. economy by 2050, electric heat-pump sales will need to grow — a lot. 

That’s clear from a new report by pro-electrification nonprofit Rewiring America. The report lays out an ambitious trajectory to replace gas, oil and inefficient electric-resistance heating systems with heat pumps. (The report also covers heat-pump water heaters, induction stoves, rooftop solar and electric vehicles.)

Heat pumps are key climate technologies. Not only do they run on electricity, but they also just move existing heat around rather than generating it from scratch, making them up to three times more efficient than heating systems that burn fossil gas. Last year, U.S. sales of heat pumps outpaced those of gas furnaces for the first time. But today, they’re still found in only 16 percent of U.S. homes, according to the new report.

Rewiring America came up with a target growth path for heat-pump sales by working backward from the end goal: having heat pumps in all homes by 2050. Because most heat pumps are installed when existing heating systems stop working and homeowners need a replacement, and because most space-heating machines have a lifetime of about 15 years, the report estimates that by 2035, all new heating systems sold would need to be heat pumps in order to achieve the 2050 target. The following chart shows a scenario in which heat pumps gradually take over the U.S. home heating market and constitute all new heating-unit sales by 2035. 

As homes replace their aging, inefficient heating systems, eventually all 140 million forecasted U.S. homes would have heat-pump systems installed by 2050, according to the report. (The report tracks heat-pump systems rather than individual heat-pump units; a household may purchase multiple units as part of a system.)

The Rewiring America team determined that these outcomes can be achieved if heat-pump sales are boosted dramatically and shift to an S-shaped growth trajectory rather than the business-as-usual scenario of linear growth based on historical sales patterns seen from 2017 to 2022. S-curves are characteristic of once-disruptive technologies that gradually become ubiquitous, including color TVs, cellphones and refrigerators. In fact, refrigerators work because of heat pumps, so heat-pump technology has basically ridden this adoption curve before.

The analysis finds that for the U.S. to hit its net-zero target by 2050, sales of heat-pump systems by 2032 would need to triple compared to the business-as-usual scenario. In the short term, the necessary increase is much smaller: Heat-pump system sales are already expected to hit about 1.6 million this year; what’s needed to achieve the 2023 target is just about 240,000 more.

“The beauty of an S-curve is that it starts out gradually. These transitions don’t happen overnight; we have time,” said Rewiring America research director Cora Wyent. ​“We can actually do this.”

If the U.S. hits the benchmarks Rewiring America has set for the next few years, that will be compelling evidence that heat pumps are shifting to a market-transforming S-curve growth path.

Still, deploying significantly more heat pumps will require a concerted effort, including training more heat-pump professionals, Wyent told Canary Media.

“We hope this report can catalyze investment in growing the heat-pump installer base,” she said, ​“because you can show that there will be market demand for this in order to meet our climate goals.”

With its unprecedented $391 billion (or more) investment in climatetech, the Inflation Reduction Act is poised to help get heat pumps and other electrified machines on the path toward S-curve growth. The massive climate bill provides Americans a tax credit of up to $2,000 for heat pumps, and lower-income families will be eligible for heat-pump rebates of up to $8,000. (The U.S. Department of Energy even has a tool to help you access them.)

What’s more, consumers can add these incentives to those offered by utilities and local and state governments, including those of Colorado, Maine, Massachusetts and New York.

In addition to the national heat-pump sales trajectory Rewiring America just published, the nonprofit is also modeling more fine-grained curves for states and counties that it plans to release later this year.

Maine has already blown past its target of 100,000 new heat pumps installed by 2025, as reported in February by The Washington Post. But the vast majority of communities don’t have a target number in mind — a gap that Rewiring America wants to help fill.

For example, in Cook County, Illinois, which is the second-most-populous county in the nation and includes Chicago, Rewiring America estimates that 19,000 heat-pump systems would need to be sold next year, which is 12,000 more than in the business-as-usual scenario. That’s ​“not a huge number” relative to the county’s 2 million households, said Rewiring America CEO Ari Matusiak.

“What I think this [analysis] will do, for the first time, is give communities a sense [of] what their year-over-year goals can be,” Matusiak said. ​“You start to realize how achievable it all really is if each community does its own part.”