Investigation of Environmental Effects Based on Exergetic Irreversibility for Display Cases’ Units in Commercial Cooling

This study examines energetic and exergetic performances of display cases’ units used in market applications depending on different refrigerants. Besides CO2 emission potential of each refrigerant based on exergetic irreversibility obtained from analyses is calculated by the method of Total Equivalent Warming Impact (TEWI). In this study, 1 kW cooling capacity and vapor compression cooling cycle is taken as reference and refrigerants of R-22, R-134a, R-404A, and R-507 together with alternative refrigerant R-407C and R152a are examined separately. According to analyses, R-404A gas, used widely in market applications, has low performance with average COP 3.89 and average exergy efficiency 55.20%. R-152a gas has the best performance by the thermodynamics parameters including COP 4.49, exergy efficiency 63.79%, and 0.23 kW power consumption and emission parameter 14097.490 ton CO2/year. Although COP is used as a criterion to evaluate the systems, this study finally emphasizes the importance of exergy analysis and TEWI method which are important methods to determine irreversibility and emission potential of the systems.