1
Country: Japan | Funding: $57.5M
Helical Fusion is developing helical-type fusion stellarator reactor. Their helical design keeps incredibly hot ionized gas contained steadily by itself, eliminating the need for external electrical power and allowing operations to run longer than with rival technologies. The company has finished testing a superconducting magnet that could work on a commercial scale. This marks the first time a commercial-scale coil has operated successfully under such conditions. The company plans to construct demonstration equipment by the decade's end. During the 2030s, Helical Fusion aims to launch its first pilot facility operating continuously while generating more power than it uses.
Helical Fusion is developing helical-type fusion stellarator reactor. Their helical design keeps incredibly hot ionized gas contained steadily by itself, eliminating the need for external electrical power and allowing operations to run longer than with rival technologies. The company has finished testing a superconducting magnet that could work on a commercial scale. This marks the first time a commercial-scale coil has operated successfully under such conditions. The company plans to construct demonstration equipment by the decade's end. During the 2030s, Helical Fusion aims to launch its first pilot facility operating continuously while generating more power than it uses.
2
Country: Germany | Funding: €607.5M
Proxima Fusion is a spinout from the Max Planck Institute for Plasma Physics that is building a quasi-isodynamic (QI) stellarator - fusion reactor that uses magnets to hold superheated gas in place so atoms can fuse and release energy. In this approach magnetic confinement toroidal currents are canceled to zero, resulting in uniquely robust characteristics. In the absence of toroidal plasma currents, current instabilities and the risk of failures that can occur in tokamaks and other stellarator concepts can be completely eliminated. The company has also developed a new heat removal technology and has already tested an island divertor at facilities at the Institute.
Proxima Fusion is a spinout from the Max Planck Institute for Plasma Physics that is building a quasi-isodynamic (QI) stellarator - fusion reactor that uses magnets to hold superheated gas in place so atoms can fuse and release energy. In this approach magnetic confinement toroidal currents are canceled to zero, resulting in uniquely robust characteristics. In the absence of toroidal plasma currents, current instabilities and the risk of failures that can occur in tokamaks and other stellarator concepts can be completely eliminated. The company has also developed a new heat removal technology and has already tested an island divertor at facilities at the Institute.
3
Country: USA | Funding: $370.5M
Type One Energy uses an enhanced version of a 1957 experimental Stellarator invented by US scientist Lyman Spitzer. The co-founders of Type One Energy built the world’s first optimized stellarator at the University of Wisconsin-Madison in the 1990s and conducted foundational stellarator research on it in the early 2000s. Using non-planar, high temperature superconducting magnets to optimize plasma flow, Type One Energy can surpass all fundamental technical barriers to achieving fusion energy at commercial scale. The company is building Infinity One prototype together with the 400 MWe Infinity Two fusion power plant. It plans to buildthe first power plant by 2034
Type One Energy uses an enhanced version of a 1957 experimental Stellarator invented by US scientist Lyman Spitzer. The co-founders of Type One Energy built the world’s first optimized stellarator at the University of Wisconsin-Madison in the 1990s and conducted foundational stellarator research on it in the early 2000s. Using non-planar, high temperature superconducting magnets to optimize plasma flow, Type One Energy can surpass all fundamental technical barriers to achieving fusion energy at commercial scale. The company is building Infinity One prototype together with the 400 MWe Infinity Two fusion power plant. It plans to buildthe first power plant by 2034
4
Country: USA | Funding: $140M
Thea Energy is developing pixel-inspired Helios fusion reactor that will offer a lower cost than competitors. It's a stellarator - a special type of reactor that uses magnets to shape plasma fuel into the desired shape. These magnets are small, identical superconducting magnets, allowing for mass production. The startup will use software to individually control each magnet to generate magnetic fields that can replicate the stellarator's unstable shape. This approach allows rapid optimization of the magnet design. Helios is projected to generate 390 megawatts of electricity at a cost of under $150 per megawatt-hour. Production is scheduled to start around 2030.
Thea Energy is developing pixel-inspired Helios fusion reactor that will offer a lower cost than competitors. It's a stellarator - a special type of reactor that uses magnets to shape plasma fuel into the desired shape. These magnets are small, identical superconducting magnets, allowing for mass production. The startup will use software to individually control each magnet to generate magnetic fields that can replicate the stellarator's unstable shape. This approach allows rapid optimization of the magnet design. Helios is projected to generate 390 megawatts of electricity at a cost of under $150 per megawatt-hour. Production is scheduled to start around 2030.
5
Country: France | Funding: €47M
Renaissance Fusion is a high-temperature superconductor and stellarator company. It has simplified the stellarator design: built 1D or 2D coils (on cylindrical surfaces, not necessarily of circular cross-section) to generate the complex 3D magnetic fields. The startup is also skipping some intermediate steps and directly depositing and patterning High Temperature Superconductors on large surfaces. The benefits are impressive: a 4x increase in magnetic field reduces the plasma volume by 256x. The liquid Lithium-based walls of the reactor stop 99.99% of the neutron energy before they can reach solid materials and make them radioactive.
Renaissance Fusion is a high-temperature superconductor and stellarator company. It has simplified the stellarator design: built 1D or 2D coils (on cylindrical surfaces, not necessarily of circular cross-section) to generate the complex 3D magnetic fields. The startup is also skipping some intermediate steps and directly depositing and patterning High Temperature Superconductors on large surfaces. The benefits are impressive: a 4x increase in magnetic field reduces the plasma volume by 256x. The liquid Lithium-based walls of the reactor stop 99.99% of the neutron energy before they can reach solid materials and make them radioactive.
6
Country: Israel | Funding: $27M
nT-Tao is developing a 20 MWe compact fusion energy system, the Tao Energy Box, based on a pulsed, high-density magnetic confinement generator, the Tao Core. By combining mature plasma physics, stellarator confinement topology, and advanced pulsed power electronics, the Tao Core enables smaller on-site power units designed for mass manufacturing and deployment close to demand. The Tao Core is designed for high magnetic fields (8–10 Tesla) within a compact stellarator geometry, while rotating electromagnetic fields reduce plasma instabilities during the heating-cycle pulses. This enables stable plasma confinement while reducing overall system size and complexity.
nT-Tao is developing a 20 MWe compact fusion energy system, the Tao Energy Box, based on a pulsed, high-density magnetic confinement generator, the Tao Core. By combining mature plasma physics, stellarator confinement topology, and advanced pulsed power electronics, the Tao Core enables smaller on-site power units designed for mass manufacturing and deployment close to demand. The Tao Core is designed for high magnetic fields (8–10 Tesla) within a compact stellarator geometry, while rotating electromagnetic fields reduce plasma instabilities during the heating-cycle pulses. This enables stable plasma confinement while reducing overall system size and complexity.
7
Country: Canada
Stellarex is a fusion energy development firm that uses a simplified Stellarator and milestone‑driven demonstrators to validate systems integration, de‑risk scale‑up, and execute a staged technology roadmap from prototypes through demonstration devices to commercial fusion power plants. It's running two device programs - SXA (intermediate prototype) and SX0 (net‑energy demonstrator) - run in parallel from 2026 through 2032, anchored by the launch of the Centre for Fusion Energy.
Stellarex is a fusion energy development firm that uses a simplified Stellarator and milestone‑driven demonstrators to validate systems integration, de‑risk scale‑up, and execute a staged technology roadmap from prototypes through demonstration devices to commercial fusion power plants. It's running two device programs - SXA (intermediate prototype) and SX0 (net‑energy demonstrator) - run in parallel from 2026 through 2032, anchored by the launch of the Centre for Fusion Energy.
