Volume 40: Energy Transitions toward Carbon Neutrality: Part III

Heating Performance Improvement on an R290 Vapor-injection Heat Pump System with Waste Heat Recovery for Electric Vehicles Yunchun Yang, Tianyang Yang, Wencong Shao, Huiming Zou, Changqing Tian

Abstract

Achieving environmental governance and energy poverty alleviation requires high-efficiency and environmental-friendly thermal management systems for electric vehicles. This study developed and tested an integrated R290 (propane) vapor-injection (INJ) heat pump system with waste heat recovery in a cold climate. Dual secondary loops are adopted considering the flammability of the R290 refrigerant. Experimental results reveal that the INJ system outperforms the basic (BAS) system by 12.1% in coefficient of performance (COP) and 36.3% in heating capacity at −20 °C/20 °C (out-cabin/in-cabin) ambient temperature. The INJ mode with 1 kW waste heat recovery can provide a 29.8% improvement in heat capacity and a 7.4% increase in COP compared to that with no waste heat at −20 °C/20 °C. This study provides experimental support for achieving efficient operation of automotive heat pump systems under a wide operation temperature range.

Keywords electric vehicles, thermal system, heat pump, R290, vapor injection, secondary loop