On December 1, 2023, Japan inaugurated JT-60SA (Japan Torus-60 Super Advanced), the largest operational superconducting tokamak in the world to date. This collaboration involving the European Union and Japan is intended to be the forerunner of the International Thermonuclear Experimental Reactor (ITER), which is currently being built in France and is expected to open in a few years.

During the inauguration ceremony, a divertor plasma with one million amps of current was demonstrated.

The JT-60SA device. Source: Fusion for Energy/National Institutes for Quantum Science and Technology

This tokamak heats up plasma kept in a strong magnetic field to up to 200 million° C (360 million° F), with currents going through it at 1 million amps. A tokamak plasma was achieved in JT-60SA for the first time on October 23, 2023.

JT-60SA is a toroidal device which operates with hydrogen. When heated to very high temperatures, the gas becomes plasma — the fourth state of matter. The heated gas will be magnetically confined for up to 100 seconds with the help of a powerful magnet system consisting of 28 superconducting coils operating in different parts of the machine. The ultimate goal is to achieve the fusion of hydrogen nuclei into one heavier element – helium – and release energy in the form of light and heat, mimicking the process that takes place inside the sun.

A total of 500 researchers have been involved in the project, which was initiated in 2007, and more than 70 suppliers have contributed to the manufacturing of its components.