Magnetic cooling more efficient and cheaper.

Astronautics Corporation of America, Ames, Iowa, and the U.S. Department of Energy's Ames Laboratory have constructed and tested a fully instrumented magnetic refrigerator operating in the near-room temperature region typical of air conditioners and refrigerators for food storage. Magnetic refrigerators exploit the magnetocaloric effect -- the ability of some metals to become hot when magnetized and cool when demagnetized. Some of the major losses present in conventional gas-compression refrigerators are absent in magnetic refrigerators. Thus, it is expected that cooling systems based on this new technology can attain substantially higher efficiency than conventional gas-compression coolers.

In addition to higher efficiency and cost savings, another advantage that magnetic refrigeration systems have over conventional vapor cycle machines is the elimination, in many cases, of the hazardous materials used for heat transfer, such as chlorofluorocarbons (CFCs) and ammonia. The magnetic technology uses water as a heat transfer medium for the refrigeration temperature range and a water-antifreeze mix to reach below freezing.

Potential areas of...