In July, IPP Greifswald received the first of five auxiliary coils that Princeton Plasma Physics Laboratory (PPPL) have had manufactured for Wendelstein 7-X. “I am very relieved that the coil has survived the 7,000 kilometre journey from Pennsylvania without damage”, said Konrad Riße, who is responsible for the auxiliary coils in the Wendelstein 7-X project. From September onwards, one coil after the other, each weighing more than a ton, will be attached to the outer vessel.

The five shop window-size coils are designed to help with precise adjustment of the magnetic fields on the plasma edge. They ensure that the outer contour of the plasma maintains exactly the shape required for subsequent experiments. The basic data for the components came from the IPP; engineers and scientists from Princeton took over the construction and supervised industrial production. Hutch Neilson, the director of advanced projects at PPPL, pointed out: “The U.S. IPP partnership in Wendelstein 7-X is the best route to discovering how to use three-dimensional magnetic fields to maintain a high-performance plasma in a steady-state without overheating the surrounding walls.” He continued: “ In return for the contribution of scientific talent and equipment such as the trim coils, the U.S. is welcomed as a partner in the Wendelstein 7-X research, with the opportunity to advance U.S. stellarator goals using the unique, world-class Wendelstein 7-X facility.”

The 4.3 million dollar investment is the largest contribution to the USA’s scientific cooperation on Wendelstein 7-X. Overall, the USA is investing more than 7.5 million dollars in its construction. In addition to the fusion laboratory at Princeton, the institutes in Oak Ridge and Los Alamos are also contributing by planning parts of the wall covering and by supplying measuring instruments for the observation of the plasma. In return, the participating U.S. institutions become partners in the Wendelstein 7-X research programme . This German-American cooperation is one of a total of nine projects under the U.S. Department of Energy’s “Innovative Approaches to Fusion” programme.

Isabella Milch, IPP