A novel ejector-based heat pump system for electric vehicle applications

The use of electric vehicles is rapidly increasing, but their range remains limited due to battery capacity constraints. This paper presents the thermodynamic analysis results of a novel type ejector-assisted heat pump designed for air-conditioning cycle (AC) for electric vehicles. Ejectors are used in cars to reduce compressor energy consumption in AC systems, which is crucial for improving electric vehicle battery efficiency. A chiller unit and an ejector were added to the heat pump system to increase the system’s efficiency. In the proposed system, environmentally friendly fluids with low global warming potential (R290, R1234yf, R1234ze, R600, R717, R744) were tested as alternatives to the refrigerants that are being phased out due to their negative effects on the environment. After applying the first and second law analyses of thermodynamics to the proposed system, an average coefficient of performance (COP) increase of 32.75% was found. According to the analysis results, among the examined fluids, R290 has the maximum COP value of 2.81. At the specified temperature values, the system using R290 as the refrigerant achieved the highest exergy efficiency, with a value of 0.24.