Superconductors may find use in wind turbines

New Scientist : Wind turbines work by spinning coils of copper wire through stationary magnetic fields. Two groups of researchers believe that by replacing the copper wire with superconducting wire, they can transform 2- and 3-MW wind turbines into 10-MW turbines. Among the other benefits, superconductors would reduce the weight, and because of the decreased resistance in the wires, they would also increase the power generation. However, some of the characteristics of superconductors make it difficult to maximize their effectiveness in turbines. For one thing, superconductors require very low temperatures to operate. To address that issue, the Suprapower consortium in Europe is using a new high- T _c superconductor that works at 20 K and therefore requires only one-seventh of the energy to cool as older superconductors. The researchers are still working to determine how to minimize warming from nearby systems. Another problem is the formation of magnetic vortices, which reduce the current flow, as the superconductors move through the magnetic field. To solve that problem, the US’s Advanced Research Projects AgencyâEnergy is funding a project led by Venkat Selvamanickam of the University of Houston, Texas. Both groups are still several years away from creating 10-MW turbines, but believe the projects could be applied to other areas of electrical generation and transmission.