JET was Europe's flagship tokamak at Culham and for decades the largest operating tokamak, the only one apart from TFTR to run deuterium-tritium campaigns. Its final D-T campaign set a 69 MJ fusion energy record; it ceased plasma operations in December 2023 and is being decommissioned and repurposed by UKAEA.
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Current state
| Status | Shut down |
| Country | United Kingdom |
| Location | Culham Campus, Oxfordshire |
| Developer | UKAEA / EUROfusion |
| Developer type | Public |
| Concept | Tokamak |
| Fuel | D-T |
| Purpose | Research |
| First plasma | 1983 |
| Public funding | EU (EUROfusion/Euratom) and UK government |
| Regulation | In decommissioning and repurposing (programme expected to run to around 2040). |
Notes
first plasma 1983 is the widely cited date; EUROfusion page only says 'over 40 years'. The DTE3 record was announced Feb 2024; month of the shot (late 2023) per secondary coverage.
Timeline
- 2021 — JET produced 59 MJ of fusion energy in a D-T campaign, then a record. (source)
- 2023-10 — JET's final D-T campaign (DTE3) produced a record 69 MJ of fusion energy over about 5 seconds using 0.2 mg of fuel. (source)
- 2023-12 — JET ended plasma operations and entered decommissioning. (source)
- 2026-08-05 — EUROfusion published a synthesis of JET's final campaigns, describing the 69 MJ result as the highest ever produced by a fusion device. (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
- JET's final fusion campaigns set a new energy record and hand ITER a legacy of irreplaceable data — EUROfusion (primary), checked 2026-10-11
- JET's swansong experiments break fusion record — The Chemical Engineer, checked 2026-10-11