French experimental nuclear fusion reactor WEST successfully confines plasma for 22 minutes, setting a new world record

by L. Godart/CEA

The French Atomic Energy Commission's (CSA) experimental fusion reactor WEST in Cadarache in southern France has succeeded in confining the high-temperature plasma needed for nuclear fusion for 22 minutes, breaking the record set by China's experimental fusion reactor in January 2025.

English Portal - Nuclear fusion: WEST beats the world record for plasma duration!
https://www.cea.fr/english/Pages/News/nuclear-fusion-west-beats-the-world-record-for-plasma-duration.aspx

France sets new plasma record in hunt for nuclear fusion | The Straits Times
https://www.straitstimes.com/world/europe/france-sets-new-plasma-record-in-hunt-for-nuclear-fusion

A nuclear fusion reaction is a phenomenon in which two or more light atomic nuclei, such as hydrogen, come close to each other and fuse to form a heavier atomic nucleus, such as helium. Because a large amount of energy is released during a nuclear fusion reaction, it is expected that this energy can be used for generating electricity, and researchers from around the world are conducting research to make nuclear fusion power generation a reality.

To cause a nuclear fusion reaction, it is necessary to maintain a plasma state in which atoms lose electrons and expose their nuclei. CSA's nuclear fusion reactor, WEST, is a tokamak type reactor that uses electromagnets to generate a strong magnetic field around the plasma, confining it at a high temperature.

CSA announced on February 18, 2025 local time that WEST had succeeded in containing plasma for 22 minutes. 'This broke the record for plasma duration achieved in a tokamak fusion reactor. This breakthrough demonstrates how our knowledge of plasmas and the technological control of plasmas over long periods of time are maturing,' CSA said in a statement.

You can see the footage of WEST actually achieving 22 minutes of plasma confinement in the YouTube video below.

WEST sets a new plasma duration record - YouTube


The experiment took place on February 12, 2025.

Plasma confinement for 1000 seconds has been achieved. The number of seconds is displayed on the monitor in the back.

The plasma confinement time continues to increase smoothly.

The plasma trapped inside looks like this.

Ultimately, plasma confinement was achieved for 1,337 seconds (approximately 22 minutes).

This means that WEST has broken the previous record of 1,066 seconds of plasma sustained, set by China's experimental fusion reactor EAST in January 2025.

China's superconducting tokamak fusion energy experimental reactor 'EAST' sets new world record in high confinement mode, moving forward to realizing fusion power generation - GIGAZINE

Confining plasma for long periods of time is an important step for ITER , an experimental nuclear fusion reactor being built through international cooperation between the United States, the EU, Japan, Russia, China, South Korea, and India.

'WEST has achieved a new important technological milestone by sustaining the hydrogen plasma for more than 20 minutes by inputting 2 MW of heating power. We plan to continue experiments at increasing power levels. This exciting achievement positions both WEST and the French community to take a lead in the future use of ITER,' said Anne-Isabelle Etienvre, Director of Fundamental Research at CSA.