ST40
ST40 is a tokamak fusion device run by Tokamak Energy in United Kingdom. It is operating. Like every fusion device built so far, it has produced no net electricity.
Reached 100 million °C plasma ion temperature in March 2022, in a compact spherical tokamak.
A privately built spherical tokamak that hit the temperature threshold for commercial fusion conditions in a machine far smaller than the national programmes.
| Organisation | Tokamak Energy |
|---|---|
| Approach | tokamak |
| Confinement | magnetic |
| Country | United Kingdom |
| Status | Operating |
| First plasma | 2018 |
| Target date | none stated |
|---|---|
| Power target | none stated |
| Energy gain target | none stated |
| Net electricity | No. no fusion device has produced any |
Other tokamak projects
Fusion needs tritium, and the world's civilian stock comes mostly from CANDU fission reactors. See the fusion overview.
ST40 in context
14 of the 24 fusion projects on record use the tokamak approach: 7 operating, 3 under construction, 3 planned and 1 closed.
Its first plasma is dated 2018, 8 years ago: the 10th earliest of 15 projects on record with a first-plasma date.
| Measure | ST40 | Median of all projects | Standing |
|---|---|---|---|
| First plasma | 2018 | 2015 | 10 of 15 (earliest first) |
Worked out from the entries on this site only, so a figure compares ST40 with what is recorded here, not with everything that exists. An entry with no value for a measure is left out of that measure's ranking and median.
Sources
- World Nuclear Association, Nuclear Fusion Power · retrieved 2026-09-07
How these sources are used, including the corrections applied on top of them and what is deliberately left blank · download the underlying data