Refrigeration Requirements of the LN2 Cryo-Cable

The paper considers the smallest size refrigeration plant likely to be required for liquid nitrogen cooled electric power transmission lines. Nitrogen, neon, hydrogen, and helium cycles are compared and it is shown that a neon cycle has considerable potential. An outline is given of a practical plant utilizing the nitrogen cycle and mainly rotating machinery, all based on present-day technology. The advantages which evaporative cooling confers on the operation of LN2 cryo-cables are explained.