Vaire Computing founder pushes 'reversible' chips that recycle waste heat

Conventional computer chips erase the information they no longer need as they perform calculations, releasing energy as heat. Earley compares that to racing through a city and braking at every intersection: the car loses momentum and must burn more fuel to accelerate again. Reversible computing aims to preserve that momentum by retaining intermediate information, which lets the circuit run the computation backward and recover some of the energy. The concept is more than 50 years old, but it has been impractical with existing transistors and circuits. Earley redesigned the hardware, developing a patent-pending type of resonator—a chip component that stores recovered energy for later reuse—which she calls “a glorified pendulum.”

Last year, Vaire announced what it called a key breakthrough: a chip with a resonator that recovered more energy than it lost, after accounting for the energy needed to power the component. For a field that has existed mostly in theory, the result was “proof of life,” the magazine reported. Igor Markov, a researcher in electronic design automation and a former professor at the University of Michigan, Ann Arbor, said “it’s clear they have something interesting,” but cautioned that the technology is still early stage. Vaire will need “a series of increasingly realistic and convincing demonstrations to attract the industry support needed for commercialization,” he added.

Earley’s route to chip design began with web programming at around age nine, and she eventually worked down to the transistor level. During her PhD at the University of Cambridge under computational biologist Gos Micklem, she first studied materials such as DNA for computation. After Micklem gave her the 1999 doctoral thesis of Michael Frank, a pioneer in reversible computing, she read it skeptically, then reread it, and gradually became convinced that the link among information, energy and heat could change computers. She redirected her thesis to the physical limits of computation and built software that could turn ordinary programs into reversible ones. Micklem recalled that he eventually stopped putting his name on her papers because he could not “stand up and give a proper talk about them.” “It was her stuff,” he said.

After completing her degree in 2021, Earley met technology entrepreneur and investor Rodolfo Rosini, and they cofounded Vaire the same year. The company has raised more than $12 million, hired Frank as a senior scientist, and begun moving reversible computing into hardware. Earley’s design work for the core circuitry took shape during the winter of 2022 in Grinnell, Iowa, where she spent weeks sketching schematics in the basement apartment of her now-wife as wind chills outside reached roughly minus 40 degrees Fahrenheit. The design came together gradually after the couple left for Las Vegas; Earley described her reaction as “a gradual wave of relief” rather than a sudden aha moment.

The next challenge is making Vaire’s drastically different chips fit into familiar devices and manufacturing systems. Earley told MIT Technology Review she wants to “tackle every part of how computers are built, and rethink it in these terms.”