High-temperature superconducting cable (Sumitomo Electric Industries, Ltd.)

Super Efficient
Superconductivity is a phenomenon whereby resistance hits zero when copper and other alloys are cooled to minus 163 degrees Celsius. When the technology is applied to power transmission cables, not only is the amount of loss from transmission cut drastically, but large volumes of power can be sent through much thinner cables.

Hindering the practical application of such cables in the past have been difficulties in manufacturing superconductive materials. SEI, however, has managed to come up with a production system capable of reliably manufacturing a cable material that experiences superconductivity when chilled to below minus 200 degrees. The company has already started mass production of the material.

SEI uses a bismuth-based substance developed by Japanese researchers as the cable's main material. The cables have liquid nitrogen chilled to minus 196 degrees flowing through them, and they are housed in chilled tubing.

Bismuth-based superconducting wire (Sumitomo Electric Industries, Ltd.)

Coming to America
The next step in the cable's development is involvement in a project conducted by the United States Department of Energy to upgrade the entire power grid of the United States by 2030 through the use of superconductive cables. From May 2006, SEI's cables will be used on a trial basis - the first such trial ever for this technology - in Albany, New York State. In the project, a 320-meter-long cable will be connected with a 30-meter-long cable, both located underground between two of the city's transformer stations, which are separated from each other by 350 meters.

SEI officials expect the United States to be the most promising market for the technology once it is ready for commercialization. Much of the country's grid was installed during the 1960s and is in urgent need of upgrading. Aging power transmission equipment has been blamed for a series of problems, including the large-scale blackout that struck New York City and other areas in the summer of 2003.

The Japanese market also has great potential. Tunnels carrying power cables currently run under Tokyo, Osaka, and other locations. Their diameters range from 2 to 3 meters, but the use of superconductive cables would allow future tunnels to be a mere 15 centimeters in diameter to send the same volume of electricity now being handled. Digging narrower tunnels would be expected to result in huge cost savings.

A US subsidiary of SEI has already launched market research and sales promotion efforts. Should those efforts be successful, the world could soon see the first-ever commercial use of superconductive power transmission cables.

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Copyright (c) 2006 Web Japan. Edited by Japan Echo Inc. based on domestic Japanese news sources. Articles presented here are offered for reference purposes and do not necessarily represent the policy or views of the Japanese Government.