Participation in the Joint European Torus JET
Until the end of its operation at the end of 2023, the JET tokamak was the largest magnetic fusion experiment in the world. Shortly before that, it generated the largest amount of energy ever released by a fusion facility. The IPP is participating in the scientific programme, which continues to analyse data from the measurement campaigns.
The JET (Joint European Torus) tokamak was operated from 1983 to 2023 as a joint European project in Culham, near Oxford, UK.
In 1991, it succeeded in releasing energy through nuclear fusion for the first time in the history of fusion research. The facility generated a fusion power of 1.8 megawatts for a duration of two seconds.
This was achieved for the second time at the end of 1993 with the now decommissioned American Tokamak TFTR (Tokamak Fusion Test Reactor) in Princeton, which released around 6 megawatts of fusion power at a heating power of 30 megawatts. Five months later, TFTR was able to increase this to 9 megawatts. While TFTR worked for the first time with a plasma in the correct reactor mixture of equal parts deuterium and tritium, JET had used a “diluted” plasma with only 14 percent tritium content in 1991.
In 1997, JET also experimented with a fuel mixture of equal parts deuterium and tritium. This generated a fusion power of 13 megawatts and a fusion energy of 14 megajoules – a world record. 65 percent of the heating power used was recovered through fusion. The JET plasma is now only a factor of six away from the ignition condition.
In October 2023, a European research team succeeded in generating 69 megajoules of energy from 0.2 milligrams of fuel. This is the largest amount of energy ever achieved in a fusion experiment (see press release).
At the end of its operating life, JET was the only magnetic fusion facility in the world capable of experimenting with the fusion fuels deuterium and tritium. All other facilities investigate model plasmas made of light hydrogen and deuterium.
JET was decommissioned as planned at the end of 2023. The measurement data collected during 40 years of operation continues to serve as an important basis for studies of the physics of fusion plasmas.
| Technical data | |
| Major plasma radius | 2.96 metres |
| Minor radii | 1.25 / 2.10 metres |
| Magnetic field | 3.4 tesla |
| Plasma current | 5 megaamperes |
| Plasma heating | 50 megawatts |
| Plasma volume | 80 cubic metres |
| Plasma mixture | hydrogen, deuterium, (tritium) |
| Plasma temperature | 100 - 200 million degrees |