Largest tokamak

The largest tokamak has a plasma volume of 160 m³ and was achieved by JT-60SA in Naka, Ibaraki, Japan and was verified on 4 September 2024.

The JT-60SA is a tokamak, a type of nuclear fusion reactor which consists of a toroidal (doughnut-shaped) containment chamber surrounded by powerful superconducting electromagnets.

During the operation of a tokamak, tritium or deuterium gas is injected into the chamber and heated into plasma – a state of matter in which electrons are separated from atomic nuclei – by a powerful electric current. As this plasma carries an electrical charge, it can be manipulated and contained by magnetic fields, which keep it from damaging the chamber walls and compress it into a small space. When the plasma reaches a certain temperature and pressure, its atomic nuclei begin to fuse together – a process that releases an enormous amount of thermal energy. This thermal energy could, in theory, provide an almost limitless supply of electricity.