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DOE OSTI · 1782048

Benefit FOA FY2015 - Solid State Magnetocaloric Air Conditioner (Final Report)

Abstract

The active magnetic refrigeration (AMR) cycle holds great promise to reduce energy consumption of space cooling and heating. It is estimated that it could achieve up to 25% improvement in energy efficiency over conventional vapor compression systems. Prototypes have been built and demonstrated the working principles and energy benefits of the technology. These prototypes however were of low specific cooling power, defined as cooling power obtainable from unit mass of magnetocaloric materials (MCM). Specific cooling power is inversely proportional to the cost of the system. Therefore, for the magnetocaloric technology to be commercially viable, the specific cooling power must be increased. To increase the specific cooling power, for any MCM, the frequency of operation must increase. However, the maximum frequency that an AMR can operate at is limited by the residence time that is required to transfer heat in and out of the regenerator during the cold and got blows. This time length is dependent on the thermal conductivity of the heat transfer medium. The higher the thermal conductivity of the heat transfer medium, the faster heat can be transferred between the medium and the MCM.

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Abuheiba, Ahmad G., Momen, Ayyoub Mehdizadeh, Zhang, Mingkan, Rendall, Joe D., Barcza, Alexander, Vieyra, Hugo. 2020-11-01. Benefit FOA FY2015 - Solid State Magnetocaloric Air Conditioner (Final Report). https://doi.org/10.2172/1782048

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