A study of capacity demands for heat pumps intermittent heating of China's residences

Heat pump heating is one of the most promising solutions for transitioning residential heating in China's cold regions, as well as hot summer and cold winter regions from centralized, continuous heating to decentralized, intermittent heating, promoting low-carbon transformation. However, the fundamental issue of the actual capacity requirements for heat pumps in intermittent heating has not yet been addressed. In view of this, this study developed a numerical model that considers the dynamic coupling characteristics between the heat pump and the building environment. Using the model, the worst startup conditions for heat pumps in intermittent heating, actual heat pump capacity demands, and the differences in capacity compared to continuous heating mode for residential buildings in 230 Chinese cities are analyzed. The findings revealed an exponential relationship between intermittent heating capacity demands and time constraints, as well as a linear relationship with heating temperature. Specifically, the impact of the set temperature on capacity demands in cold regions and hot summer and cold winter regions is 22.8 W/(m2 center dot degrees C) 2 center dot degrees C) and 32 W/(m2 center dot degrees C), 2 center dot degrees C), respectively. These findings provide insights into the planning and design of future intermittent heating renovation projects in China.