‘West’ tokamak machine at Cadarache beats January record set in China
A nuclear fusion machine in southern France has set a new record for plasma duration, beating a record set in China earlier this year.
On 12 February, the “West” machine, at the Alternative Energies and Atomic Energy Commission’s (CEA) Cadarache site, maintained plasma for more than 22 minutes – a total of 1,337 seconds.
In so doing, it broke the previous record achieved in January by China’s East machine of 1,066 seconds by over 25%.
In the process the plasma reached a temperature of 50 million °C.
“West has achieved a new key technological milestone by maintaining hydrogen plasma for more than twenty minutes through the injection of 2 MW of heating power,” said CEA director of fundamental research, Anne-Isabelle Etienvre.
“Experiments will continue with increased power. This excellent result allows both West and the French community to lead the way for the future use of Iter [the International Thermonuclear Experimental Reactor].”
The West and East tokamaks are both contributing to the €20bn Iter nuclear fusion project at Cadarache. Iter is the largest global fusion experiment.
The increase in plasma duration is significant for two reasons. On the one hand it demonstrates increasing maturity in the knowledge of plasmas and their control and the hope that such stabilisation can be achieved for longer periods of time.
It also is necessary to ensure that all the plasma facing components are able to withstand the extreme high temperature, high pressure and high radiation level conditions within the tokamak without malfunctioning or polluting the plasma.
This is key for Iter, which is intended as a large-scale research and demonstration device on the path towards commercial electricity generation.
Background: Tokamaks Pacing The Way For Iter
Over the coming months the West team intends to double down on efforts to achieve very long plasma durations – up to several hours combined – but also to heat the plasma to even higher temperatures with a view to approaching the conditions expected in fusion plasmas.
A tokamak is a device that uses powerful magnets to create a magnetic field capable of confining plasma. Often in the shape of a ringed donut, a tokamak heats deuterium and tritium within the magnetic field to plasma temperatures, which can be over six times hotter than the core of the Sun.
There are a number of tokamak facilities around the world, with the US, Germany, UK, South Korea, and Japan leading a race to unlock the potential of nuclear fusion.
Experimental fusion reactors such as East, as well as many others across the world, are constantly refining what the Iter fusion plant is going to be like when it begins operation.
Commercial nuclear reactors in operation today are fission reactors. Fission and fusion are both nuclear processes that involve splitting or combining atoms to release energy. The main difference between the two is the type of atoms involved. Fission splits a heavy atom into lighter atoms. Fusion combines two light atoms into a heavier atom.
