Lajunen, A., "Energy Efficiency and Performance of Cabin Thermal Management in Electric Vehicles," SAE Technical Paper 2017-01-0192, 2017.
The energy used for cabin cooling and heating can drastically reduce the operating range of electric vehicles. The energy efficiency and performance of the cabin heating, ventilation and air conditioning (HVAC) system depend on the system configuration and ambient conditions. The presented research investigates the energy efficiency and performance of cabin thermal management in electric vehicles. A simulation model of cabin heating and cooling systems was developed in the AMESim software. Simulations were carried out in the standard test cycles and one real-world driving cycle to take into account different driving behaviors and environments. The cabin thermal management performance was analyzed in relation to ambient temperature, system efficiency and cabin thermal balance. The simulation results showed that the driving range can shorten more than 50% in extreme cold conditions. The energy efficiency of cabin thermal management can be improved by using a heat pump and recovering waste heat from powertrain components. According to the simulations results, a heat pump system with an electric heater can significantly reduce the HVAC system energy consumption. In mild ambient temperatures, between -5 °C and 10 °C, the driving range was increased by 6-22% depending on the driving cycle. Waste heat recovery from powertrain components further improved the energy efficiency of the heat pump system resulting in a decrease of 2-4% in the vehicle energy consumption. Simulation results also show that the battery heating in cold conditions can increase the energy consumption more than 20%.