Proxima FusionIn Development
Proxima's quasi-isodynamic stellarator power plant concept, published in February 2025 as the first stellarator power plant design optimized simultaneously for plasma physics, engineering and maintenance and validated through peer review. Quasi-isodynamic optimization cancels the net toroidal current, which is what lets a stellarator run continuously and avoid the disruptions that plague tokamaks.
Latest update Aug 1, 2026
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Design stage. The first commercial Stellaris plant is planned for the site of the decommissioned Gundremmingen nuclear fission station in Bavaria, with deployment targeted for the mid-to-late 2030s once Alpha has demonstrated net energy gain. Engineering design will be driven directly by data from Alpha.
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Announced next steps from Proxima Fusion that mention Stellaris.
2031
Build and commission the ~€2B Alpha demonstrator at Garching and operate it from 2031, aiming to make it the first stellarator ever to produce more fusion energy than it consumes and to generate the data that sets the Stellaris engineering design.
Mid-to-late 2030s
Build Europe's first commercial stellarator fusion power plant on the site of the decommissioned Gundremmingen nuclear station in Bavaria, reusing existing grid connections and industrial infrastructure.
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On Oct. 28, 2026, during the German chancellor's visit to Tokyo, Proxima Fusion signed a memorandum with Fujikura to assess a high-temperature superconducting tape supply in Lower Saxony and a memorandum with Kyoto Fusioneering to expand work on gyrotrons and the fuel cycle. Proxima says it expects about 20,000 kilometers of tape for its Alpha demonstrator and about 40,000 kilometers for each Stellaris plant. The notes describe feasibility work and continued cooperation, not a factory decision or a purchase order.
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Commonwealth Fusion Systems
Compact, high-field tokamak designed to demonstrate net energy from fusion. It uses high-temperature superconducting magnets to achieve reactor-class magnetic fields in a much smaller machine, with peer-reviewed projections of roughly Q ~11 and ~140 MW of fusion power.
Commonwealth Fusion Systems
CFS' first planned grid-scale commercial fusion power plant, designed to deliver about 400 MW of clean electricity using the HTS magnet and tokamak stack proven through SPARC. The project is officially named the Fall Line Fusion Power Station and is planned for a 100-acre site at the James River Industrial Center in Chesterfield County, Virginia.
Helion Energy
7th-generation fusion prototype designed to demonstrate electricity production from fusion using Helion's pulsed magneto-inertial architecture and direct electricity recapture.
Helion Energy
First commercial fusion power plant, designed to generate 50+ MWe. Located in Malaga, Chelan County, Washington, on land leased from Chelan County PUD near Rock Island Dam. Power will be marketed by Constellation Energy to Microsoft data centers.
