Quick Dips

Hot Superconductors

Three New Zealand companies and their American partner recently achieved a world first with the use of a new large-scale electromagnet for high-temperature superconductivity (HTS) applications.

Developed by Alphatech International, Industrial Research Limited and American Superconductor Corporation, through research supported by ECNZ, the magnet is also one of the first commercial uses of high temperature superconductivity anywhere in the world.

Superconductors are materials which lose all resistance to electricity at low temperatures. Prior to 1986, the operating temperature had to be close to absolute zero (-273^oC). With the discovery of particular copper oxide ceramics which super-conducted at the higher temperature of liquid nitrogen (-196^oC), the possibilities of "high-temperature" superconductivity opened up.

Superconductivity research leader at Industrial Research, Jeff Tallon, says the research behind this development has been supported for 10 years by the New Zealand government, and that it is pleasing that New Zealanders are at the forefront of the commercialisation and manufacture of HTS technology.

The launch of the magnet can be seen as the forerunner of a range of HTS-based components, he says. Many of these technologies will offer significant improvements for electrical power generation, transmission and efficiency, hence the interest from ECNZ.

The new magnet has been installed to replace a conventional magnet attached to a particle accelerator at the Institute of Geological and Nuclear Science's Lower Hutt laboratory. The IGNS installation provided a chance to demonstrate that practical application of HTS technology is now feasible.

The maximum field produced by the magnet is around 0.7 Tesla; the Earth's magnetic field is of the order of 0.00005 Tesla.

The magnet will enhance the performance of the institute's $2.5 million accelerator, which plays an invaluable role in New Zealand's fisheries, agricultural, atmospheric and seismic research programmes. Other applications include archaeology and radiocarbon dating of ancient artifacts and artworks. [see "Counting Atoms One by One by One", Feb 1994]

Alphatech International's Managing Director, Richard Neale, says the market potential for beam transport magnets themselves is in the tens of millions of dollars worldwide.

"There are a lot of advantages to using the HTS material once it's developed a little bit further, so we see a very big potential for it.

"We're already in discussion with other groups from Europe and Australia about building the next generation of HTS magnet. We know the next magnets will have even higher performance."