500,000 watts, four seconds: Successful start for heating system with radio waves in Wendelstein 7-X

Great success for German-Belgian fusion research: In the world's largest stellarator Wendelstein 7-X at the Max Planck Institute for Plasma Physics (IPP) in Greifswald, an innovative heating system with radio waves has now been used for the first time. Using a new type of antenna, the power of more than 500,000 watts could be radiated into a helium plasma for four seconds without disturbing the plasma operation. The new ion heating system for the Greifswald fusion experiment is based on the design of the Laboratory for Plasma Physics at the Royal Military Academy in Brussels and was built in intensive collaboration with the Institute for Plasma Physics and the ZEA-1.

The new heating system contains several improvements over the traditional designs, based on earlier research in the TEXTOR tokamak experiment at Forschungszentrum Jülich. In addition, the antenna can be moved to the optimal position in relation to the plasma.

In the coming weeks, the power of the radio wave heater will be further increased to more than one million watts for ten seconds by commissioning a second generator. The goal is to reach an ion temperature of at least 100 million degrees, which is required for the fusion of hydrogen isotopes into helium.

Last month, the IPP was already able to announce records in the fusion experiment: On 15 February 2023, the researchers managed an energy turnover of 1.3 gigajoules - the target for 2023 was one gigajoule. In addition, a new record was set for the discharge time at Wendelstein 7-X: the hot plasma was maintained for eight minutes.

See MPI press release (22.02.2023)