Helical Fusion, a startup originating from Japan's National Institute for Fusion Science (NIFS), announced the successful completion of a critical performance test for a large high-temperature superconducting (HTS) coil. The test confirmed the component's ability to carry a significant electrical current within a strong magnetic field, a fundamental requirement for the magnetic confinement of plasma in its proposed reactor. This result validates the company's proprietary manufacturing process for the complex, continuously wound helical coils that are central to its design. Source: Reuters Fusion

The company's approach is based on a helical reactor, a type of stellarator, which differs from the more common tokamak design by using a set of complex, twisted external magnets to shape the plasma. This configuration theoretically allows for steady-state, continuous operation, avoiding the plasma disruptions inherent in the pulsed, current-driven operation of many tokamaks. The primary engineering challenge for stellarators lies in the precise fabrication of these intricate magnet systems. The use of HTS materials is intended to enable stronger magnetic fields and more compact designs compared to traditional low-temperature superconductors.

This configuration theoretically allows for steady-state, continuous operation, avoiding the plasma disruptions inherent in the pulsed, current-driven operation of many tokamaks.

Helical Fusion's work builds on decades of public research at NIFS, which operates the Large Helical Device (LHD) in Toki, Gifu Prefecture. The LHD is one of the world's foremost stellarator experiments and has provided a deep well of operational data and engineering experience in managing helically-confined plasmas. The startup aims to commercialize this expertise, translating the scientific achievements of the LHD into a viable power plant architecture. This transition from a national laboratory to a private entity reflects a growing trend in the fusion industry to accelerate development timelines.

This successful component test is a key enabling step in the company's roadmap. With the validation of its HTS coil manufacturing and performance, Helical Fusion will proceed with the development of other critical subsystems. The company has stated its goal is to construct a prototype reactor by 2032, followed by a commercial reactor. The performance of this prototype will be closely watched as a measure of the commercial viability of the helical stellarator concept, particularly its ability to achieve high plasma density and temperature in a continuous operational mode. Source: Reuters Fusion