Magnetic cooling takes off

- The principle of magnetic cooling is based on the magnetocaloric effect, which was discovered in 1881 by Warburg. Magnetocaloric materials heat up when they are positioned in a magnetic field and cool down to a lower temperature than their initial temperature when this field is removed. For many years, these materials operated only at extremely low temperatures in intense (5-10 tesla) magnetic fields which could only be generated by superconducting magnets. Materials containing gadolinium and manganese, capable of operating at room temperatures with more powerful permanent magnets, have emerged over the past few years. Magnetic refrigeration has a number of benefits (expected coefficients of performance of 6-12, no greenhouse emissions, simple maintenance, potential use over a very wide temperature range (-260°C to + 40°C) but this noiseless technology requires further development to raise the capacity above the current capacity limit of roughly 15 kW. - Cooltech, a corporate member of the IIR based in Alsace, has developed cutting-edge technology that is taking magnetic refrigeration out of the laboratory and onto the industrial refrigeration market. This technology recently won a French innovative technology award (Lauréat du Concours National Enterprise Innovante 2003). When powerful permanent magnets became available, Christian Muller, Managing Director, seized the opportunity to develop magnetic refrigeration systems for the food industry, domestic appliances, commercial refrigeration and the catering industry, at a cost very similar to that of traditional vapour-compression systems. Cooltech draws on the expertise of several specialists in the field of materials and magnetic fields. The temperature range envisaged is -30 to +40°C and the current capacity of systems produced by Cooltech is 1.2-4 kW and rising. If you are interested in magnetic refrigeration you will enjoy attending the 1st IIRConference on Magnetic Refrigeration at Room Temperature. Contact Peter Egolf, President of the IIR Working Party on Magnetic Refrigeration: peter.egolf@eivd.ch