Japanese start-up Helical Fusion has closed its Series A round, securing funding of JPY 2.3bn ($15m). This brings total capital, including grants and loans to JPY5.2bn to support its Helix Programme, a roadmap toward a fusion power plant in the 2030s.
The funding round attracted investors including SBI Investment, Keio Innovation Initiative (KII), and 19 other institutions, with support from public financial institutions. The fusion reactor being developed by Helical Fusion is based on the stellarator design.
Helix says the concept builds on nearly 70 years of global research, particularly at Japan’s National Institute for Fusion Science (NIFS) that hosts the Large Helical Device (LHD), one of the world’s most advanced stellarator facilities. The company was founded in 2021 by Takaya Taguchi, a former banker, and two scientists from NIFS.
Helical Fusion aims to deliver the world’s first commercially viable stellarator for electricity generation. The flagship of Helical Fusion’s effort is Helix KANATA, a full-scale pilot plant designed for steady-state, net-electric fusion power. Preceding it is Helix HARUKA, an intermediate device for component and system validation. Together, they form the Helix Programme. Helical Fusion plans to build a pilot reactor with a generation capacity of 50-100 MWe and have it operational around 2040.
In 2024, Helical Fusion conducted a critical test involving a 19kA current in its proprietary High-Temperature Superconductor (HTS) cable. Helical Fusion, together with NIFS, has developed a new HTS conductor that can be scaled and engineered into high-performance magnets.
In October 2023 Helical Fusion was selected by the Japanese Ministry of Education, Culture, Sports, Science & Technology (MEXT) for its total JPY6.5bn Small Business Innovation Research (SBIR) programme to develop cutting-edge fusion technologies. Helical Fusion was one of four companies selected to receive JPY2bn. However, the company estimates it will need JPY1,000bn to build its pilot reactor, develop high-temperature superconductivity technology for coils, and establish safety rules to gain local construction approval.
The planned reactor could be a type of stellarator known as a heliotron. This comprises two continuous helical coils capable of operating without a plasma current, similar to the LHD at NIFS. It would use a unique design in which the magnetic field required for plasma confinement is generated solely by electromagnetic coils. This allows for stable plasma confinement over long periods.
In April 2024, Helical began joint research with Professor Komurasaki at Toyko University’s Department of Aeronautics and Astronautics on optimisation and mass production of gyrotrons through advanced simulation techniques. The gyrotrons would be used to heat the plasma in the helical-stellarator.
