Commonwealth Fusion Systems (CFS) and Tokamak Energy Inc. are the two magnetic confinement tokamak fusion developers to receive a portion of the $46 million in funding announced by the Department of Energy in late May for the first 18 months of a public-private Milestone-Based Fusion Development Program aimed at developing fusion pilot plant designs and resolving related scientific and technological challenges within five to 10 years.

Princeton Stellarators Inc. (PSI) and Type One Energy Group are two of the eight fusion developers selected by the Department of Energy in late May to receive a total of $46 million in funding to kick off a public-private Milestone-Based Fusion Development Program aimed at developing fusion pilot plant designs and resolving related scientific and technological challenges within five to 10 years. The DOE’s selections cover an array of plasma confinement concepts, including the magnetic confinement stellarators being developed by PSI and Type One more than 70 years after the stellarator was first envisioned.

Nuclear Newswire previously took a close look at two of the DOE’s picks: Realta Fusion and Zap Energy (“innovative concept”) and Focused Energy and Xcimer Energy (inertial fusion). Here, we’ll examine how PSI and Type One are engineering solutions to the fusion plasma confinement challenge. Both companies are benefiting from recent advances in computing power and high-temperature superconducting (HTS) magnets. It’s in plans for design, manufacturing, assembly, and control of their stellarators that they differ.

Focused Energy and Xcimer Energy are two of the eight fusion developers the Department of Energy selected in late May for funding under the public-private Milestone-Based Fusion Development Program, and the only developers using an inertial confinement concept. The Milestone program, announced in September 2022, was open to any fusion developer willing to undergo a competitive merit-review process, regardless of fusion confinement concept. But the prospects for inertial fusion concepts might have gotten a boost from Lawrence Livermore National Laboratory’s December 2022 achievement of scientific breakeven at the National Ignition Facility (NIF), which was announced shortly before the application window for the Milestone program closed.

Realta Fusion of Madison, Wis., and Zap Energy of Everett, Wash., are just two of the eight fusion developers selected by the Department of Energy for funding last week under the public-private Milestone-Based Fusion Development Program. They are the two companies with power plant concepts that don’t fit neatly into established fusion confinement categories. As energy secretary Jennifer Granholm said when she announced the awardees, “Some are working on more technically mature approaches like tokamaks and stellarators and laser inertial fusion, and others are working on innovative concepts with lower technical maturity like mirror and Z-pinch, which could lead to more compact and lower cost systems.”

General Atomics (GA) announced on October 20 that it has developed a steady-state, compact advanced tokamak fusion pilot plant concept “where the fusion plasma is maintained for long periods of time to maximize efficiency, reduce maintenance costs, and increase the lifetime of the facility.”