Minimal performances of high Tc wires for cost effective SMES compared with low Tc's

On the basis of a 22MJ/10MVA unit without stray field, we determine minimal performances for High [T.sub.c] Superconducting (HTS) wires, in order to obtain HTS Superconducting Magnetic Energy Storage (SMES) competitive compared with Low [T.sub.c] Superconducting (LTS) ones. The cost equation mainly considers the wire volume, the fabrication process and losses. We then recommend HTS critical current densities and operating magnetic fields close to the present state of the art for short samples. A 30% gain for HTS SMES compared with LTS one could be expected.