Feasibility and performance study on hybrid air source heat pump system for ultra-low energy building in severe cold region of China

The application of air source heat pumps is mainly restricted by the outdoor ambient temperature, which causes poor application effects in the severe cold region of China. This paper proposes an innovative hybrid energy system of solar air collector + air source heat pump + energy storage that is utilized to save energy for ultra-low energy building in severe cold region. The feasibility and performance of this hybrid energy system is studied in Hailar which is located in severe cold region of China. The hybrid energy system is introduced and the dynamic characteristics of the key components of the system are analyzed in combination with the local meteorological conditions. The results indicate that, in Hailar, where the outdoor heating calculation temperature is lower than -30 degrees C and solar energy resources are not particularly abundant, the peak inlet air temperature of the air source heat pump increases by no less than 10 degrees C and the coefficient of performance of the system is expected to be higher than 3.0 under extremely low temperature conditions. Warm air from solar air collector can be supplied for heating without ASHP operation if its temperature is higher than 25 degrees C. These results provide some references for the application of the hybrid energy system in the severe cold region of China. (C) 2019 Elsevier Ltd. All rights reserved.