FAST

FAST stands for Fusion by Advanced Superconducting Tokamak. Led by Starlight Engine with Kyoto Fusioneering and academic and industrial partners, it is a private-sector-led Japanese project targeting a fusion-power demonstration in the 2030s. Its planned low-aspect-ratio tokamak would combine burning deuterium–tritium plasma with energy conversion, fuel-cycle equipment and maintenance systems. The project therefore addresses the connection between plasma performance and the engineering of a complete plant. Starlight Engine: FAST conceptual design completed, 27 November 2025

Completion of the conceptual design was announced on 27 November 2025, following the project’s November 2024 launch. That announcement identified engineering design, site selection, regulatory work and procurement as subsequent steps. A July 2026 update confirms that engineering design and preparation for construction are progressing. The evidence supports a project in development; it does not establish a constructed machine or achieved fusion-electricity output. Starlight Engine: funding and engineering-design update, 15 July 2026

FAST’s published technical scope includes producing and controlling D–T burning plasma, breeding and recovering tritium, and integrating the plant’s engineering systems. High-temperature superconducting magnets and advanced blankets are part of the intended design. These goals expose the difference between a successful plasma experiment and a repeatable power-generating system. Published specifications describe planned operating conditions. In particular, fusion output and plasma energy gain should not be presented as electricity available to customers or as measured performance of the future plant. Starlight Engine: FAST project

The conceptual-design announcement targets completion of an engineering design report by 2028 and construction after 2028, subject to the intervening engineering, site and regulatory work. Its approximately 50 MW-class fusion output is a design figure for fusion power, not achieved electrical output. The source directory also records an April 2026 joint-research announcement involving the University of Tokyo, Starlight Engine and Kyoto Fusioneering. Conceptual-design announcement Joint-research announcement