The low thermal conductivity of High Temperature Superconducting ceram
ic YBCO(<1Wm(-1)K(-1) at 77K) in comparison with normal metal such as
copper (similar to 480 Wm(-1)K(-1) at 77K) suggests their use as curre
nt leads. We demonstrate a modular lead design which has very low resi
stance contacts and where the power dissipated at an arbitrarily chose
n current level of 100A is several orders of magnitude lower than that
dissipated by the normal metal leads presently used in such applicati
ons. This suggests that significant cost savings may be made resulting
from the reduced liquid helium boil-off rate. The leads are fabricate
d by novel ceramic processing techniques which give a high degree of u
niformity and reproducibility, and strengths in flexure approaching 20
0MPa for the individual elements, the highest values reported.