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Electrochemically driven phase transformation for high-efficiency heat pumping

Kim, Junyoung·Mishra, Abhiroop·Braun, James E.·Groll, Eckhard A.·Rodríguez-López, Joaquin·Ziviani, Davide
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Abstract

To reduce energy consumption and improve energy utilization in space conditioning, advanced heat pumping technologies are needed. The chemical looping heat pump (CLHP) is a promising thermodynamic cycle that has theoretically shown the potential to achieve a cooling coefficient of performance (COP c ) increase of over 20% relative to conventional vapor compression systems. In this paper, the key process of the CLHP is experimentally demonstrated, and the system performance and non-ideal behavior are predicted using the component-level models. The results show the feasibility of electrochemical phase change of a working fluid; the peak COP c was 7.64 with a cooling capacity of 3.6 mW (cooling density of 2.57 W m -2 ) at both sink and source temperature of 23°C based on laboratory experiments. The COP c can theoretically reach up to 13 at a temperature lift of 15°C as long as an electrochemical cell can achieve a greater degree of conversion.

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37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRYChemistryEnergy & FuelsMaterials SciencePhysicsair conditioningchemical looping heat pumpelectrochemicalheat pumpnot-in-kind technology

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Kim, Junyoung, Mishra, Abhiroop, Braun, James E., Groll, Eckhard A., Rodríguez-López, Joaquin, Ziviani, Davide. 2023-04-11. Electrochemically driven phase transformation for high-efficiency heat pumping. https://doi.org/10.1016/j.xcrp.2023.101369

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