World’s largest operating tokamak begins commissioning with major 8-meter coils upgrade

JT-60SA has entered integrated commissioning after a two-year shutdown and major upgrades by European and Japanese teams.

The upgrades include new 8-meter in-vessel coils, diagnostics, cryopumps, heating systems, a new first wall, and a divertor.

Plasma experiments are planned for late 2026, following validation of the new systems and operating procedures.

The work will help test technologies for longer, hotter plasma operation and provide key data for ITER and future fusion reactors.