Conventional conductors allow electric current to flow through them, although some energy is dissipated into heat as the current encounters a resistance. For temperatures below the critical temperature (Tc) a superconductor exhibits no measurable electrical resistance for DC currents. Furthermore much larger current densities can be carried than with normal Cu wire. The superconducting energy storage device is able to compactly store large energies in a compact volume with no storage losses.
Superconducting magnetic energy storage devices are already in use for power quality in high-value manufacturing or experiments. The technology is, however, expensive as it uses 'LTS', low temperature superconductivity, which requires liquid helium at 4.2K to operate. The opportunity for this project comes from a new superconductor MgB2, discovered in 2001, which operates at higher temperatures. A higher operating temperature means a dry cooling system can be used which simplifies the design, reduces the size and hence the overall cost.
The project assesses the suitability of MgB2 conductors for application in superconducting magnetic energy storage, (SMES) for future energy networks. The goal is to fabricate and test an MgB2 magnet coil and short length conductor to provide the necessary information for potential UK SMES manufacturers to assess both the conductor and magnet development. Due to the current facilities at the University of Southampton, a relatively small investment converts to a larger impact. Using the wide bore magnet facility, an MgB2 coil can be tested in a large enough magnetic background field at temperatures between 10 and 20K, mitigating the cost of constructing a full size MgB2 magnet. Data from the coil measurement, together with tests on short length conductors, will form the basis for the conductor and application assessment. Superconducting magnet manufacturers SIEMENS Magnet Technology and Oxford Instruments have already expressed their interest in the project.