Energy, exergy, environmental, and economic (4E) analysis and selection of best refrigerant using TOPSIS method for industrial heat pumps

The global implementation of the Montreal Protocol has accelerated research in the last decade to develop low GWP refrigerants, and numerous low GWP refrigerants have been uncovered. A broad energy, exergy, envi-ronmental and economic (4E) analysis is required to know the overall benefits of the new low GWP refrigerants, especially in the context of heat pumps for industrial heating. In this paper, an attempt has been made to analyze the popular refrigerants based on 4E analysis, and the best refrigerants are selected based on the technique for order of preference by the similarity of ideal solution (TOPSIS). Total equivalent warming impact (TEWI) has been considered for environmental analysis. Fourteen refrigerants that include the popular hydrofluorocarbons, alkenes, and hydrocarbon refrigerants have been considered for the study. The condenser temperature was varied from 45 -95 degrees C. Considering the present emission factor of India, R407C, R1270, R290, R152a, and R1234ze(E) are found to be the best refrigerants for the condenser temperatures ranging from 45 to 65 degrees C, 66 - 68 degrees C, 69 - 77 degrees C, 78 - 92 degrees C, and 93 - 95 degrees C, respectively. This paper will be a helpful guide for the industries to select the best refrigerant for their applications.