Exergy and Exergoeconomic Analyses of Air Conditioning Applications Integrated with an Air Membrane Exchanger

Abstract

The results obtained from the exergoeconomic and exergy analysis of a model of a generic air conditioning (A/C) system without and with an air membrane exchanger using three commercially available refrigerants: R410A, R407C, and R134a, are reported. The model used specialized software that was validated against recently published data and showed good agreement. A/C systems are energy intensive and consume a significant portion of global electricity. Improving their efficiency by even a small amount will produce considerable savings, reduce running costs, and lower pollution emissions. The efficiency of the same A/c system without and with a membrane was investigated for different ambient temperatures, relative humidities (RHs), and pressure ratios of the compressor. It was shown that the inclusion of a membrane improved the efficiency of the system for all three refrigerants tested, particularly at higher ambient temperature. Both the coefficient of performance and exergetic efficiency reduced with the increase in the pressure ratio due to increasing fuel exergy and losses. In all system components except one, it was found that the source of the cost is inefficiencies; hence, increasing the efficiency at the expense of the non-exergy cost will improve the cost effectiveness of the entire system.