FAST (Fusion by Advanced Superconducting Tokamak)

FAST is a Japanese private-sector-led fusion power demonstration project led by Starlight Engine with Kyoto Fusioneering as engineering partner. It plans a JT-60SA-class low-aspect-ratio D-T tokamak of ~50 MW fusion output; the conceptual design was completed in November 2025, with construction targeted after 2028 and power demonstration in the 2030s.

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Current state

Notes

~50 MW is fusion (thermal) power, not MWe, so target output not recorded. Funding for engineering design being sought in 2026. Kyoto Fusioneering itself is primarily a component/engineering supplier; FAST is the device-level project.

Timeline

• 2024-11-12 — Kyoto Fusioneering and partners launched FAST, aiming for fusion power generation by the late 2030s. (source)
• 2025-11-27 — Starlight Engine completed FAST's conceptual design and published Japan's first private-sector-led conceptual design report. (source)

The timeline is append-only: corrections are added as new entries. Stated targets appear in the current-state table, never as milestones.

Related projects

• ARC (Commonwealth Fusion Systems) Design · United States
• BEST (Burning Plasma Experimental Superconducting Tokamak) Under construction · China
• CFEDR / China Fusion Energy Co. demo reactor (successor to CFETR) Design · China
• EAST (Experimental Advanced Superconducting Tokamak) Operating · China
• EU DEMO (EUROfusion Demonstration Power Plant) Concept · European Union
• Helix HARUKA (Helical Fusion) Under construction · Japan
• HH170 (Energy Singularity) Design · China
• HH70 (Energy Singularity) Operating · China

See all 51 projects in the Fusion Energy Companies & Projects Tracker →

Sources

1. Completion of Conceptual Design for the Fusion Energy Demonstration Project FAST — Kyoto Fusioneering (primary), checked 2026-10-11
2. Fusion Energy Power Generation Demonstration Project, FAST — Kyoto Fusioneering (primary), checked 2026-10-11