Researchers at the University of Connecticut have found a possible means of using magnetic fields along with something called the Kondo Effect to cool materials.
The new physics identified through this work suggest a road map for the development of materials with strong “magnetocaloric” properties, the tendency of a material to change temperature in the presence of a magnetic field.If such a material comes out of this research, air-conditioning units would shrink in size because the need for a bulky compressor and heat exchange tubing would disappear and the only moving part might be a fan to move the cooled air. While there are semiconductor materials presently available that use the Peltier effect to heat or cool, they aren't terribly efficient as compared to standard cooling techniques, at least not at a large scale. They work well at a small scale to cool electronics or diode lasers.
“The Kondo Effect in YbInCu4 [Ytterbium Indium Copper four] turns on at a very low temperature of 42 Kelvin (-384F),” said Hancock, “but we now understand why it happens, which suggests that it could happen in other materials near room temperature.” If that material is discovered, he adds, it could revolutionize cooling technology.
Household use of air conditioners in the U.S. accounts for more than $11 billion in energy costs and releases 100 million tons of carbon dioxide annually. Use of the magnetocaloric effect for magnetic refrigeration as an alternative to the mechanical fans and pumps in widespread use today could significantly reduce those numbers.
It will be interesting to see if the researchers will be able to find the proper materials to make the magnetocaloric effect work at room temperatures.