Helical Fusion achieves milestone with high-temperature superconducting coil test

Helical Fusion has successfully completed a critical performance test of a large-scale high-temperature superconducting (HTS) coil designed for use in commercial nuclear fusion reactors. The HTS coil was subjected to conditions replicating the complex magnetic environment within a fusion device, including self-generated and external magnetic fields. It achieved a stable superconducting current of 40 kA under a 7-tesla magnetic field at 15 K (-258°C). This marks the world’s first demonstration of such an HTS coil meeting the technical requirements of a commercial-scale fusion reactor.

The coil, notable for operating without electrical insulation during the test, is a fundamental component for generating the strong magnetic fields required to confine and stabilize superheated plasma in Helical Fusion’s helical stellarator devices. The use of high-temperature superconductors allows efficient magnetic field generation with reduced cooling demands compared to conventional low-temperature superconductors.

This milestone validates Helical Fusion’s scale-up of superconducting magnet technology and supports progression to the integrated demonstration device, Helix HARUKA. The demonstration device will combine the HTS magnets with plasma heating and energy capture systems to simulate continuous fusion operation. Helical Fusion’s roadmap targets steady-state commercial fusion power generation with its Helix KANATA pilot plant during the 2030s.

The milestone was achieved in collaboration with Japan’s National Institute for Fusion Science (NIFS) using its unique large-diameter, high-field test facility. Helical Fusion benefits from over 60 years of helical stellarator research and is supported by Japan’s Ministry of Education, Culture, Sports, Science and Technology through the SBIR Phase 3 fusion development program. The company has secured significant funding and partnerships to advance its mission of realizing commercial fusion energy based on the helical stellarator approach.

This breakthrough marks a major step toward stable, scalable, and commercially viable fusion power by demonstrating the critical magnetic confinement technology capable of continuous operation in practical fusion reactors. It positions Helical Fusion as a leading player in next-generation fusion energy systems that diverge from traditional tokamak designs, offering a promising path for clean, limitless energy production.​