Currently the technlology adopted in fridges and airconditioners is, compresses a gas into a liquid and circulated through inner walls of the fridge and in turn the liquid absorb the heat of the object kept inside the fridge and make cool.
Now some British scientists developed technology using magnetic theory for cooling and this is best part of the technology that reduces power consumption by 40 percent and make no use of harmful gases.
The technology uses gadolinium (Gd), a silvery-white metal that is strongly attracted by a magnet, has a magnetic disordering temperature of 20C, and a giant magnetocaloric effect of several degrees. The element is subjected to a magnetic field that results in heating of the element due to alignment of electrons in sequence, now this heat is absorbed by circulating a liquid and the magnetic field is removed and the element cools below its staring temperature. A Cambridge University spin-out company, Camfridge Ltd, has built two prototype magnetic fridges that use gadolinium. This element is very expensive so now Professor Derek Fray, a leading expert in materials chemistry is working on an alloy that has a negative magnetocaloric effect - it cools in a magnetic field. This could also be harnessed for fridges through a heat exchange process.
This technology will bring a new revolution in fridge and cooling appliance industry and will surely be appreciated by the consumers as it is a green technology and promises reduced power consumption.