Simulation Study on a Hybrid Adsorption Refrigeration System Driven by Low-Grade Heat Sources From Fuel Cells

The efficient utilization of low-grade heat sources in the range of 60-80℃ exhausted from the proton membrane exchange fuel cells is the key to improving its overall efficiency. A hybrid adsorption refrigeration system using desiccant coated heat exchangers is proposed in this paper to extract these low-grade heat sources for efficient cooling and dehumidification. This hybrid system can be operated in three working modes to achieve different purposes of cooling, dehumidification and cold-water supply. The performance of the hybrid system is evaluated theoretically and simulation results reveal that these three working modes can be powered effectively by low-grade heat sources at 60∼80℃. The coefficient of performance (COP) of Mode 1 and Mode 2 decline with the increase of the inlet hot water temperature, which the COP of Mode 3 exhibits a trend of increasing first and then decreasing. The COP of Mode 2 is superior to other two modes, which can be up to 0.971. Adopting the hybrid system to exploit low-grade heat sources at 70℃ can significantly enhance the overall efficiency of proton membrane exchange fuel cells, reaching 76.8%. © 2022, Science Press. All right reserved.