Comprehensive 3E (Energy, Exergy, Environmental) Analysis and Multi-Criteria Selection of Low-GWP Refrigerants for Sustainable Refrigeration Systems

This study presents a comprehensive 3E (Energy, Exergy, Environmental) analysis and multi-criteria selection of nine low global warming potential (GWP) refrigerants as alternatives to R404A in commercial refrigeration systems. Thermodynamic calculations were performed using the REFPROP 10.0 database for evaporation temperatures between -20 °C and 0 °C and condensation temperatures between 35 °C and 45 °C. Environmental effects were also evaluated for the same temperatures. The TOPSIS (Technique for Order Preference by Similarity to Ideal Solution) method was applied with base-case criteria weights of Total Equivalent Warming Impact (TEWI) (40%), Exergy Efficiency (35%), and COP (25%). R1234ze(E) achieved Rank 1 in 13 of the 15 operating conditions; R290 led at the remaining two, where it marginally outperforms R1234ze(E) on all three criteria simultaneously. Sensitivity analysis across five weight scenarios confirmed the robustness of these rankings under all tested weight distributions. The choice between R1234ze(E) and R290 represents an operational sustainability trade-off: R1234ze(E) offers practical safety advantages (A2L) for retrofit applications, while R290 provides superior environmental credentials (GWP = 3, PFAS-free) for new installations. All top-ranked refrigerants comply with the GWP thresholds of the Kigali Amendment and the EU F-Gas Regulation (2024), confirming their long-term regulatory viability.