This industrial heat pump is cheaper to run than a boiler.

Inside, the startup Skyven Technologies was running a mechanical apparatus dubbed Arcturus, which turns waste heat into industrial-grade steam. It’s so new that I was the first outsider to see the contraption up close — signing my name in slot No. 1 in the log book. But, soon, Skyven will show it off to manufacturers who want to save money on energy bills while cutting their carbon emissions.

Industrial heat causes about 20% of global carbon emissions, per a McKinsey analysis. Very high-temperature processes, like melting ores for steelmaking, are tough to replicate without fossil fuels. But, in Skyven’s analysis, about half of those industrial heat emissions come from making steam, usually in boilers that burn gas or other fuels. Skyven, and a growing cadre of startups, are designing clean, electric, hyper-efficient heat pumps to take over that task.

They have their work cut out for them: Right now, the U.S. is home to about 39,000 industrial boilers, according to Richard Hart, a decarbonization expert at the think tank American Council for an Energy-Efficient Economy. The steam they generate is used to sterilize injectable drugs, turn pulp into paper, pasteurize milk, cure lumber, and more.

Boilers are reliable and not particularly expensive — and in the U.S., natural gas is cheap — so it’s hard for cleaner alternatives to compete. ACEEE, which tracks announcements of new industrial clean-heat projects, namely heat pumps or thermal batteries, currently registers just 19 completed installations nationwide.

Skyven tackles the tricky economics by focusing on energy savings. The startup installs Arcturus at no cost to the customer, alongside existing gas boilers. The heat pump taps into the factory’s waste heat, which helps it reach high temperatures with far more efficiency than older technologies. Skyven and the customer split the savings from making cheaper electric steam, but if electricity prices spike, Skyven temporarily switches back to the gas boiler to avoid higher costs.

“What we want to do as a business is make industrial manufacturing in the U.S. and worldwide a lot more efficient, by being the leader in upcycling industrial heat and reusing it without having to create it anew,” Skyven founder and CEO Arun Gupta told me.