JT-60SA

JT-60SA is the world's largest operating superconducting tokamak, built jointly by Japan (QST) and the EU (Fusion for Energy) as an ITER satellite. After first plasma in October 2023 it was shut down for upgrades; integrated commissioning restarted in 2026, with a roughly six-month experimental campaign expected from the end of 2026.

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Current state

Notes

Status "Operating" reflects the machine being in commissioning/restart rather than a long shutdown; plasma experiments (OP2) expected from end-2026.

Timeline

• 2023-10-23 — JT-60SA achieved first plasma. (source)
• 2026-03 — Europe and Japan restarted JT-60SA integrated commissioning after upgrades including new in-vessel coils, first wall, divertor and heating systems. (source)
• 2026-05 — ANS reported JT-60SA upgraded and ready for restart, with over 150 research proposals under review. (source)

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

NNN coverage

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
• FAST (Fusion by Advanced Superconducting Tokamak) Design · Japan
• Helix HARUKA (Helical Fusion) Under construction · Japan
• HH170 (Energy Singularity) Design · China

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Sources

1. Europe and Japan restart JT-60SA — Fusion for Energy (primary), checked 2026-10-11
2. JT-60SA upgraded and ready for restart — ANS Nuclear Newswire, checked 2026-10-11