Method for estimating the refrigeration costs of supercritical helium cooled cable superconductors

Refrigeration costs constitute an important aspect of the economics of force-cooled cable superconductors. The refrigerator power required to operate a forced cooled superconducting magnet is analyzed. The paper develops a simple method for estimating the total refrigerator power associated with a given length of cabled conductor of specified geometry. The estimate relies on the thermodynamics of supercritical helium in the superconducting cable. Finally, the technique is used to point out what features of the forced cooled superconductor design are desirable from a refrigeration cost standpoint.