Japan's FAST nuclear fusion project releases compact tokamak design

Japan’s FAST (Fusion by Advanced Superconducting Tokamak) nuclear fusion project, led by Starlight Engine and Kyoto Fusioneering, has completed its conceptual design phase just one year after launching in November 2024. The project centers on a compact, low-aspect-ratio tokamak designed to generate and sustain burning plasma using a deuterium-tritium fuel mix, targeting a fusion output of about 50 MW. Unlike experimental reactors focused solely on plasma physics, FAST integrates power generation systems, fuel breeding cycles, and heat extraction into a single operational unit, aiming to demonstrate commercial viability by the 2030s. Key innovations in the FAST design include the use of high-temperature superconducting (HTS) magnets, liquid breeding blanket systems, and efficient tritium fuel cycle technologies. The compact size enabled by HTS coils reduces manufacturing time and costs while enabling high-pressure plasma generation. The project also plans to test advanced components such as innovative divertors and new materials in future