Two fusion firms unveil blueprints for commercial reactors in the 2030s
For decades, nuclear fusion—the reaction that powers the sun—has been the ultimate energy dream. If harnessed on Earth, it could provide endless, carbon-free power. But the challenge is huge. Fusion requires temperatures hotter than the sun's core and a mastery of plasma—the superheated gas in which atoms that have been stripped of their electrons collide, their nuclei fusing. Containing that plasma long enough to generate usable energy has remained elusive. Now, two companies—Germany's Proxima Fusion and Tennessee-based Type One Energy—have taken a major step forward, publishing peer-reviewed blueprints for their competing stellarator designs. Two weeks ago, Type One released six technical papers in a special issue of the Journal of Plasma Physics. Proxima detailed its fully integrated stellarator power plant concept, called Stellaris, in the journal Fusion Engineering and Design. Both firms say the papers demonstrate that their machines can deliver commercial fusion energy. Related: Nuclear Fusion's New Idea: An Off-the-Shelf Stellarator At the heart of both approaches is the stellarator, a mesmerizingly complex machine that uses twisted magnetic fields to hold the plasma steady. This configuration, first dreamed up in the 1950s, promises a crucial advantage: Unlike its more popular cousin, the tokamak, a stellarator can operate continuously, without the need for a strong internal plasma current. Instead, stellarators use external magnetic coils. This design reduces the risk of sudden disruptions to the plasma field that can send high-energy particles crashing into reactor walls. The downside? Stellarators, while theoretically simpler to operate, are notoriously difficult to design and build. Recent advances in computational power, high-temperature superconducting (HTS) magnets, and AI-enhanced optimization of magnet geometries are changing the game, helping researchers to uncover patterns that lead to simpler, faster, and cheaper stellarator designs. Two…