According to the researchers, in the future, our refrigerators could use magnets to keep the food cold. Besides the fact that one such refrigerator uses less power and runs quieter than a conventional fridge, it wouldn’t contain any hydrofluorocarbons (HCF), gases that contribute to the greenhouse effect.
It all comes down to something called the magnetocaloric effect, wherein a changing magnetic field within a material causes it to get colder.
This phenomenon is studied by Sujoy Roy, a physicist with Lawrence Berkeley National Laboratory in California. He said that the trick is to find an alloy that exhibits the effect at room temperature, without using so much energy input.
Along the time, many researchers have become interested in alloys that display a giant magnetocaloric effect. In 2008, a team at Southern Illinois University found out how to get a huge magnetocaloric effect at room temperature. To do that, they used a nickel-manganese-gallium alloy with added copper.
After reading about their experiment, Roy is now using Berkeley Lab’s Advanced Light Source, which produces light brighter than that of the sun, to examine how the alloy’s elements change as they undergo the effect. Until now, Roy discovered that the addition of copper causes the alloy’s magnetism to weaken, while simultaneously causing its nickel-gallium bond to become stronger.
Once the giant magnetocaloric effect he will be fully understood and harnessed , it could be used not only in refrigerators, but also in air conditioning units, laptops and vehicles.