WEST is CEA's upgraded Tore Supra tokamak with a full tungsten environment, used to test ITER-relevant long-pulse operation. On 12 February 2025 it held a plasma for 1,337 seconds, a world duration record; CEA aims to raise heating power from 2 MW to 10 MW for ~1,000-second pulses.
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Current state
| Status | Operating |
| Country | France |
| Location | CEA Cadarache, Saint-Paul-lez-Durance |
| Developer | CEA (French Alternative Energies and Atomic Energy Commission) |
| Developer type | Public |
| Concept | Tokamak |
| Fuel | D-D |
| Purpose | Research |
| First plasma | 2016-12 |
| Public funding | CEA / EUROfusion |
Notes
first plasma (Dec 2016, as WEST) per Wikipedia. No 2026 milestone found.
Timeline
- 2024-12 — WEST reached an 824-second plasma with 1.93 GJ of injected energy. (source)
- 2025-02-12 — WEST sustained a hydrogen plasma for 1,337 seconds at ~50 million °C with 2 MW of heating, a world record for duration. (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
- FAST (Fusion by Advanced Superconducting Tokamak) Design · Japan
- HH170 (Energy Singularity) Design · China
- HH70 (Energy Singularity) Operating · China
See all 51 projects in the Fusion Energy Companies & Projects Tracker →
Sources
- WEST sets a new plasma duration record — CEA-IRFM (primary), checked 2026-10-11
- Nuclear fusion: WEST beats the world record for plasma duration — CEA (primary), checked 2026-10-11
- WEST (formerly Tore Supra) — Wikipedia, checked 2026-10-11