What is it?
Magnetic refrigeration is an emerging[1] refrigeration process. It utilizes a completely different thermodynamic process to produce cooling compared to traditional vapor-compression refrigeration cycles. In theory, magnetic refrigeration systems could replace all types of cooling and refrigeration equipment throughout the commercial sector, from small display case coolers, to large rooftop units.
How does it work?
Magnetic refrigeration utilizes the thermodynamic process known as the magnetocaloric effect. Metals that exhibit the magnetocaloric effect change temperature when they are subjected to a magnetic field. Place the material in the magnetic field, and it will heat up. Remove the magnetic field, and it returns to room temperature. This oscillating temperature effect is coupled with a water based fluid (usually a water-glycol mix) to generate the cooling and move heat as needed without the use of HFC[2] refrigerants.
What are the most appropriate applications?
To date, most magnetic refrigerators are being used to cool electronic equipment in space telescopes and satellites. The commercial applications most near “market ready” stage are small refrigerators or coolers with cooling loads under 400W (two residential refrigerators). Larger units are being researched, but are years away from being market ready.
What are the savings?
The magnetic refrigeration systems created to date are prototypical, and there are not measured savings results. Theoretically modeled energy savings range from 25% – 50% of typical cooling system savings when permanent magnets are used.
What are the non-energy benefits?
The most significant non-energy benefit is the elimination of HFC refrigerants. The refrigerant for magnetic systems are metal beads or plates, which do not emit or leak greenhouse gases.
What is the cost?
Costs are highly proprietary and not released. Magnetic units will be expensive since the magnets and magnetocaloric materials are often made of elements people haven’t heard of, such as gadolinium, lanthanum, terbium, and dysprosium.
What is the status/availability of the technology?
This technology is not widely available since it’s still under development.
[1] Emerging in this case means prototype stage. This technology is still very young.
[2] HFC stands for HydroFluoroCarbons, refrigerants composed of hydrogen, fluorine, and carbon.
