Selection of refrigerant based on multi-objective decision analysis for different waste heat recovery schemes

Waste heat generation, upgrading, and refrigeration are the fundamental ways to recover and utilize waste heat. Rationalizing the use of refrigerants also contributes to creating energy savings and minimizing carbon emissions. This study evaluates the thermodynamics, economics, and environment of different refrigerants in three waste heat recovery schemes: generate electricity, heat pump, and refrigeration. Based on this, the entropy weight and technique for order preference by similarity to an ideal solution are combined to assess the overall performance of the refrigerants. A thorough analysis reveals that R1234ze(E) could replace R245fa and R123 in the organic Rankine cycle. The best refrigerant for vapor compression refrigeration and high-temperature heat pump systems is R1243zf. In addition, the multi-objective decision analysis shows that the performance difference among the nine selected refrigerants is the total cost, followed by the environmental impact. The approach successfully recognizes the variations between different refrigerants in the same waste heat recovery scheme and gives a thorough evaluation. It sets instructions for the future use of eco-friendly refrigerants and their application of waste heat recovery schemes.