Performance analysis of DX and flooded evaporators with eco-friendly refrigerants in medium-scale food storage systems

The environmental impact of refrigerants with high Global Warming Potential (GWP) used in refrigeration systems within the food industry drives the need for sustainable alternatives. This study comprehensively compares the performance of Direct Expansion (DX) and Flooded evaporator systems utilizing low-GWP refrigerants R290 (Propane), R1270 (Propene), and R717 (Ammonia) in a medium-scale food storage facility, using the CoolPack simulation program. Simulations were conducted under realistic operating conditions, with an evaporator temperature of -18°C, a condenser temperature of 28°C, and a fixed cooling capacity of 20 kW. The analysis focuses on key performance parameters, including Condenser Capacity ( ), Compressor Power Consumption ( ), Coefficient of Performance (COP), Refrigerant Mass Flow Rate ( ), and Annual Energy Consumption. The simulation results demonstrate that R717 (Ammonia) exhibits the best performance, achieving the highest COP values for both DX (COP = 3.318) and Flooded (COP = 3.342) systems, alongside the lowest annual energy consumption (DX = 52926 kWh, Flooded = 52552 kWh). While R1270 (Propene) and R290 (Propane) showed lower COP values than R717, with 3.282 and 3.283 for DX systems and 3.254 and 3.243 for Flooded systems, respectively, they still presented good energy efficiency. This study provides a comprehensive comparison for selecting sustainable refrigerants in medium-scale refrigeration systems.