A Madison, Wisconsin startup combining decades of stellarator optimization research with high-temperature superconductors and advanced manufacturing to build a fusion power plant that never disrupts.
Stellarators confine plasma using externally generated twisted magnetic fields, eliminating the large internal plasma current that makes tokamaks vulnerable to violent disruptions. Type One Energy, founded in 2019 and headquartered in Madison, Wisconsin, is building on decades of stellarator optimization theory developed at institutions including the Max Planck Institute for Plasma Physics, Oak Ridge National Laboratory, and the University of Wisconsin-Madison. The company was co-founded by CEO Chris Mowry, a veteran energy executive, alongside fusion scientists including Dr. David Anderson (UW-Madison) and experts from the HSX (Helically Symmetric eXperiment) and W7-X stellarator programs.1
Type One's reactor concept, called FusionDirect, applies quasi-helically symmetric (QHS) magnetic geometry -- the same optimization class demonstrated on the HSX stellarator at UW-Madison. QHS configurations reduce the neoclassical transport losses that plagued earlier stellarators, yielding confinement approaching tokamak quality without the disruption risk. The company pairs this magnetic design with rare-earth barium copper oxide (REBCO) high-temperature superconducting tape wound onto additively manufactured coil forms. This combination addresses the stellarator's historical weakness: the difficulty of manufacturing precisely shaped 3D coils. By 3D-printing the structural winding forms and then winding HTS tape onto them, Type One aims to make stellarator coils as reproducible as industrial components.3
Type One Energy has raised over $100 million across multiple rounds, including a $29 million Series A in 2023 and a subsequent Series B led by Breakthrough Energy Ventures. The DOE selected Type One for its milestone-based Fusion Milestone Program in 2024 and separately awarded the company funding through the INFUSE (Innovation Network for Fusion Energy) program for collaborations with national laboratories. In 2025, the company announced a partnership with Congressionally Directed Medical Programs (ARPA-E predecessor) and expanded its engineering team significantly, opening additional facilities in Oak Ridge, Tennessee -- proximate to Oak Ridge National Laboratory's stellarator expertise and supercomputing resources.4
No stellarator has yet produced a burning plasma, and the jump from the research-scale HSX and even Wendelstein 7-X to a net-electricity stellarator power plant is enormous. Type One's HTS coil fabrication approach is promising but must demonstrate that additively manufactured winding forms can hold the tight tolerances required for good magnetic surfaces -- errors of even a few millimeters can degrade confinement. The company must also address the tritium breeding, neutron shielding, and materials challenges common to all D-T fusion concepts. The stellarator's inherent advantage -- steady-state, disruption-free operation -- is real and valuable for a power plant, but it comes packaged with geometric complexity that makes every engineering subsystem harder than its tokamak equivalent. Type One's deep stellarator heritage and aggressive manufacturing strategy position it well, but the proof will come only when plasma flows through a full-scale HTS stellarator coil set.5