Cool currents: superconductors' evolution for power transmission

摘要

RESEARCHERS AND ENGINEERS toil at discovering new solutions and technologies that could make the recent northeastern U.S. blackout a rare occasion in the future. One of the prominent technologies that has captured a great deal of attention is superconducting power cable. As of 2000, there were about 8,000 km of high voltage (69 kV and above) underground cable in the United States, generally in urban areas. It is envisioned that power companies could increase the capacity of these underground cables by five to seven times by retrofitting copper cables with superconducting cables through existing underground utility conduits. For instance, a high-temperature superconductor (HTS) cable operating at 115 kV can have the same MVA rating and lower impedance than a 345-kV cable. This combination of high power capacity and compact size makes HTS cables a superior solution in situations where conventional cables and/or overhead lines would be difficult to site in highly congested networks and high-priced geographical locations.