Nuclear-fusion firm says plant will deliver electricity to grid – but big questions remain

An illustration of a tokamak nuclear fusion reactor chamber.Credit: Ruslanas Baranauskas/SPL

One of the world’s leading private fusion companies, Commonwealth Fusion Systems (CFS), has published a suite of papers that the firm says “confirm” that its ARC power plant, if built as intended, will produce more electricity than it consumes. But some researchers say that results from an operational fusion reactor are needed to validate their predictions and that big engineering challenges remain to be solved.

Private fusion firms have received almost US$10 billion of investments over the past decade, with the promise that fusion — the reaction that powers the Sun — could be harnessed on Earth to produce clean electricity. CFS, which is based in Cambridge, Massachusetts, and other firms including Helion Energy in Everett, Washington, and TAE Technologies in Foothill Ranch, California, say that they will deliver commercial fusion plants by the early 2030s.

Physicists at the US National Ignition Facility in Livermore, California, created the first fusion reaction that briefly produced more energy than it consumed in 2022. But no team has made a reactor that can produce energy continuously, or enough to leave a surplus, or proved that a reactor can be run in an economically viable way.

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