Wendelstein 7-X converted into a record-setting reactor

The Wendelstein 7-X facility in Greifswald is the world’s largest fusion reactor of the stellarator type. After reopening following an extensive refurbishment, it set a new record on February 15, 2023, in testing nuclear fusion as a potential energy source.

For a full 8 minutes, the reactor was able to generate plasma, achieving an energy throughput of 1.3 gigajoules. This means the stellarator exceeded its previous figures by a factor of 17. With 14 to 18 gigajoules, a four-person household in Germany could be supplied with electricity for a year.

Like tokamak facilities, stellarators use magnets. These are arranged around the plasma, which is used as fuel for energy generation. Researchers in Greifswald extended the reactor’s operating time and increased its energy conversion with a new cooling system.

The plasma in nuclear fusion reaches temperatures of several million degrees. To ensure it remains contained, the surrounding materials must meet the highest requirements. These materials should possess a high melting point and high corrosion resistance, as well as high strength at extreme temperatures.

Rare earths such as scandium oxide help to enhance these properties in the materials used inside the reactor. To ensure the magnets also withstand reactor conditions, superconducting REBCO (rare-earth barium copper) tapes are frequently utilized. These contain various rare earths such as neodymium oxide and gadolinium oxide.

Tokamak, stellarator and laser fusion—Which nuclear fusion technology will ultimately win the race and then supply us with virtually free energy cannot yet be said. However, we already know that an investment in scandium oxide, neodymium oxide and gadolinium oxide could promise attractive returns in the future, including tax-free purchase and tax-free profits after a one-year holding period.