Can the dream of fusion power be realized? (M. Mitchell Waldrop, 15 January 2024, Canary Media)

“There is a coming of age of technological capability that now matches up with the challenge of this quest,” says Michl Binderbauer, CEO of the fusion firm TAE Technologies in Southern California.

Indeed, more than 40 commercial fusion firms have been launched since TAE became the first in 1998 — most of them in the past five years, and many with a power-reactor design that they hope to have operating in the next decade or so. ​“I keep thinking, oh sure, we’ve reached our peak,” says Andrew Holland, who maintains a running count as CEO of the Fusion Industry Association, an advocacy group he founded in 2018 in Washington, D.C. ​“But no, we keep seeing more and more companies come in with different ideas.”

None of this has gone unnoticed by private investment firms, which have backed the fusion startups with some $6 billion and counting. This combination of new technology and private money creates a happy synergy, says Jonathan Menard, head of research at the Department of Energy’s Princeton Plasma Physics Laboratory in New Jersey, and not a participant in any of the fusion firms.

Compared with the public sector, companies generally have more resources for trying new things, says Menard. ​“Some will work, some won’t. Some might be somewhere in between,” he says. ​“But we’re going to find out, and that’s good.”

Granted, there’s ample reason for caution — starting with the fact that none of these firms has so far shown that it can generate net fusion energy even briefly, much less ramp up to a commercial-scale machine within a decade. ​“Many of the companies are promising things on timescales that generally we view as unlikely,” Menard says.

But then, he adds, ​“we’d be happy to be proven wrong.”

With more than 40 companies trying to do just that, we’ll know soon enough if one or more of them succeeds. In the meantime, to give a sense of the possibilities, here is an overview of the challenges that every fusion reactor has to overcome, and a look at some of the best-funded and best-developed designs for meeting those challenges.