TOKYO, Japan — Decarbonizing modern society will require making certain clean-energy technologies ubiquitous. Swap all cars for electric! Fly planes without fossil fuels! Cook without fire! With such grand societal shifts to contemplate, it’s refreshing to realize that some of the necessary changes have in fact already been accomplished on a large scale somewhere in the world.
Heat pumps are one of those successes. As Canary Media noted in our recent buyer’s guide to this all-electric heating and cooling device, the heat pump is an up-and-coming entrant in the U.S. clean energy arena. The product just had a record year with 4.3 million unit sales, beating gas furnace purchases for 2022. Now a whole new set of federal incentives are available through the Inflation Reduction Act, with some households eligible to receive up to thousands of dollars to replace fossil-fueled heating with heat pumps.
It’s heady times for a technology that wasn’t getting much airtime just a few years back. In the Carolinas and Alabama, central heat pumps serve more than 40 percent of housing units. But overall, heat pumps have reached just 11 percent of U.S. housing units. They’re far from commonplace. But they need to become commonplace to meet the nation’s climate goals, according to the electrification advocates at Rewiring America. Forthcoming analysis from the group finds that heat pumps need to effectively take over all sales for space heating by 2035 so that the population of operational space-heating equipment converts to heat pumps by 2050.
Shortly after I wrote about heat pumps being the new kid on the clean energy block, I embarked on a journey around East and Southeast Asia, and I quickly realized something: The same heat pumps that are deemed new and exciting in the U.S. are old news elsewhere, ubiquitous in the urban landscapes of places like Tokyo, Ho Chi Minh City and Taipei.
Arriving in Tokyo from Los Angeles late one February night and emerging from the airport, I was startled to encounter a tingly, chilly phenomenon that permeated the air and seeped into my very bones. Asking around and with some help from Google Translate, I learned that this sensation is referred to as “winter.” Luckily, the insufficiently insulated apartment I was staying in had a heat pump, so I flipped it on and had warm air rushing at me almost instantaneously.
When the sun rose the next morning, I set out to stroll the quiet side streets of Asakusabashi, which I shared with bicyclists and elegantly coiffed furball dogs in strollers. I noticed heat pumps on every block, as their external fan units often face the street from exterior walls or balconies. Some households adorned their heat pumps with potted plants or encircled them in gardens. This lent the appliances a semblance of individual character, making them extensions of the personalities dwelling within those walls.
It turns out Japan was selling twice as many heat pumps as the U.S. in 2021, according to a study in Nature Energy published last year (bear in mind that the U.S. population is about 2.5 times bigger than Japan’s). A study from the Heat Pump and Thermal Storage Technology Center of Japan says 90 percent of households in the country have heat pumps for heating and cooling (though it’s not entirely clear how the center arrived at this statistic).
As I moved through Vietnam and Taiwan, the rule held constant: Where there was heating and cooling, there were heat pumps. I share this not because this was the most galvanizing sight to see in any of these places but because it reveals something about the task ahead for the U.S. as it seeks to remove carbon emissions from the built environment.
The prospect of equipping millions of homes with fossil-free heat pumps looks considerably less daunting when you realize that other countries have already done this for millions of homes. In fact, some 190 million heat pumps were operating worldwide as of 2021, according to the International Energy Agency, even before rapid growth in 2022.
The size of that real-world adoption means a few crucial things.
First, it proves that manufacturers know how to produce capable hardware products at a large scale. Companies that make electric vehicles or home battery packs are still working through their growing pains to set up mass-volume production, and that comes with occasional missteps. As far as heat pumps go, the legwork of proving out a product and building production capacity is already done.
Second, the grid can handle mass heat-pump adoption. You can’t add millions of new electric appliances to the grid without influencing the broader system somehow. But heat pumps, at least, seem relatively benign.
It helps that they’re far more energy-efficient than older electric heating systems, so in some cases, they could reduce household power consumption. In any case, other countries have absorbed an influx of heat pumps without having to overhaul the grid in the ways that may be necessary to accommodate, say, charging depots to handle the massive power flows to electric bus fleets. Even induction stoves pose a potential challenge to the grid since they entail significant new power demand in the evening hours when solar power goes away. Heat pumps, not so much, although the countries I visited in Asia still have plenty of work to do to power those heat pumps with clean energy instead of largely fossil-fueled electricity.
Third, heat pumps are easy on the customer. Prospective heat-pump buyers don’t need to learn a whole new way to make themselves comfortable at home the way EV drivers need to master a new approach to fueling. You just press a button and the heat pump gives you the right temperature. I figured it out intuitively, even while befuddled by jet lag and handling remote controls labeled in Japanese and Mandarin.
A lot of open questions hover over the transition to clean energy: How do we store renewable power for the days and weeks when there’s not much sunshine or wind? Can we effectively make all the concrete, fertilizer and steel we need without massive carbon emissions? Are home cooks ready to give up gas stoves en masse?
It’s too early to definitively answer any of those, but in looking beyond the U.S., it’s clear that it’s possible to manufacture and install heat pumps, on a home-by-home basis, for one of the world’s largest economies. It’s up to the U.S. to execute on that potential — and to make sure electrician shortages and other permitting hangups don’t get in the way.