Performance and environmental effects of refrigerants used in the rooftop air-conditioning of building for carbon emission: A case of theoretical and numerical modelling

This study analyzes six different refrigerants with different characteristics using the same rooftop air conditioner considering the environmental effects unlike other studies. All evaluations are drafted in two different scenarios, thanks to the equal refrigerant charge amount and equal energy consumption to make the performance review more accurate. Cooling capacity, energy consumption, temperature and pressure values are obtained through a numerical simulation program so as to obtain performance values. In order to prove the accuracy of the values obtained from the simulation program, the rooftop air conditioner using R410A refrigerant is tested in the laboratory environment. The Life Cycle Climate Performance method is used for environmental analyses to calculate the carbon emissions of six different refrigerants in two different scenarios. These experimental tests are carried out at outdoor temperatures of 20ºC, 25ºC, 30ºC and 35ºC. The maximum difference in cooling capacity, energy consumption and energy efficiency is determined as 2.8% between simulation and experimental outputs. According to the results from and equal refrigerant charged and equal energy consumption scenarios, R410A, R454B and R32 refrigerants are found to have better cooling capacities than other refrigerants in performance analyses.