Thermo-economic and environmental analysis of a small capacity vapor compression refrigeration system using R290, R1234yf, and R600a

Abstract

Abstract In recent years, the international community has been continuously encouraged the development of new vapor compression refrigeration systems, that operate with ecological refrigerants, to replace systems with non-ecological refrigerants. In view of this need, this paper presents a mathematical model of a small cooling capacity vapor compression refrigeration system. This model was used to design an energy-efficient system, with low cost, that operates with the most appropriate ecological refrigerant in terms of overall environmental impact, focusing the refrigerants R290, R600a, and R1234yf. The environmental analysis was performed based on TEWI (Total Equivalent Warming Impact), while the thermo-economic analysis was performed based on COP (Coefficient of Performance), ηexergy (Exergy Efficiency), and C ˙ total (Total plant cost rate). Also, the contribution of each individual cost rate related to C ˙ total was identified. A similar procedure was also carried out on the total exergy destruction. The thermo-economic and environmental analysis indicated that the system with R290 has higher energy, exergy, environmental, and economic performance among the evaluated systems for the studied thermodynamic conditions. Thus, the system with R290 is the most suitable to replace systems with R134a. Finally, analyzing the three cost rates related to C ˙ total in each system, it was noted that the operational cost rate was the most relevant cost, and it corresponds to more than 73% of the C ˙ total value, while the penalty cost rate due to carbon dioxide emission was the least relevant cost, corresponding to less than 2.60% of the C ˙ total value.