Japan achieves world’s first successful nuclear fusion coil test

Japanese startup Helical Fusion has achieved a world-first milestone by successfully testing a large-scale high-temperature superconducting (HTS) coil designed for commercial nuclear fusion reactors. The coil maintained a stable superconducting current of 40 kA under a 7-tesla magnetic field at 15 K (-258°C), replicating the magnetic environment inside a fusion device. This breakthrough positions Helical Fusion as a leading contender in the global race to develop stable, continuous fusion power and brings Japan closer to realizing infinite clean energy through fusion. Helical Fusion’s Helix Program aims to complete further HTS magnet and integrated system tests by the late 2020s, followed by the construction of Helix HARUKA, a demonstration device for stable fusion reactions. By the 2030s, the company plans to launch Helix KANATA, a pilot plant designed for 24/7 stable operation, net positive electricity output, and efficient maintenance—key requirements for commercial fusion viability. The company lever