DIII-D
DIII-D is a tokamak fusion device run by General Atomics in United States. It is operating. Like every fusion device built so far, it has produced no net electricity.
Operating for the US Department of Energy since the late 1980s, and the longest-running large tokamak in the world. Its purpose is stated as establishing the scientific basis for optimising the tokamak approach rather than demonstrating power, and most of what the field knows about tokamak plasma control came from machines like it.
The United States has no large tokamak under construction and its national programme rests on a machine that first ran in 1986, while its private companies raise billions. That gap between the public and private effort is particular to the American programme.
| Organisation | General Atomics |
|---|---|
| Approach | tokamak |
| Confinement | magnetic |
| Country | United States |
| Status | Operating |
| First plasma | 1986 |
| 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.
DIII-D 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 1986, 40 years ago: the 2nd earliest of 15 projects on record with a first-plasma date.
| Measure | DIII-D | Median of all projects | Standing |
|---|---|---|---|
| First plasma | 1986 | 2015 | 2 of 15 (earliest first) |
Worked out from the entries on this site only, so a figure compares DIII-D 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