By the end of this year, Dr. Kilian Bartholomé and his team at the Fraunhofer Institute for Physical Measurement Techniques (IPM) in Freiburg, Germany, expect to finish developing a prototype of a very efficient heat-pump system based on magnetocaloric technology and a special heat-transfer technique that eliminates the need for vapor compression systems and environmentally damaging refrigerants.
The prototype, using a patented heat transfer concept, would be the world’s first refrigerant-free heat-pump system with a capacity of 300W (putting it in the range of a household refrigerator, typically between 50 and 100W), a material temperature change of 35°K, and a coefficient of performance (COP) of greater than five, said Bartholomé.
“Efficient, refrigerant-free heat pumps based on the magnetocaloric cycle have the potential to revolutionize cooling technology,” he said.
The researchers in Freiburg have been working on this project for four years and hope to break a world record for magnetocaloric heat-pump systems with regards to the frequency at which the magnet vibrates (greater than 10hz). In addition, they aim to achieve 50% of the theoretical maximum efficiency level possible for magnetocaloric systems. (Comparable existing systems currently reach approximately 30%.)
According to Bartholomé, the larger the system’s frequency, the cheaper it can be. “The goal is to eventually be able to build magnetocaloric systems that are cost-competitive with vapor-compression systems,” he said.
“Efficient, refrigerant-free heat pumps based on the magnetocaloric cycle have the potential to revolutionize cooling technology,”.Dr. Kilian Bartholomé, Fraunhofer IPM
For Fraunhofer there is still a long way to go until commercialization, which Bartholomé estimates at about five years. “First applications will be niche like medical applications, where it is easier to enter the market with a new technology, since the cost pressure is not as high as, for example, in household applications,” he said.
Read this article in its entirety in the October 2019 issue of Accelerate Magazine