Experimental Study on Air Source Heat Pump Heating System Based on Phase Change Heat Storage

Abstract

With continuous advancement of policies regarding to energy conservation, emission reduction and clean heating, the market for air source heat pumps is rapidly growing. In the current situation, the need to reduce operating costs of heat pump heating has become urgent. This study proposes a distributed air source heat pump heating system based on phase change heat storage. The system utilizes a phase change heat storage device to transfer heat load from high electricity price periods to low electricity price periods. In order to reduce operating costs, control schemes are formulated based on peak-valley electricity pricing. The system has been tested in Qinghai Province, a high-altitude area in China. Results demonstrate that the system helps to achieve the decoupling between heating and power. The proportion of low-valley electricity consumption in the system increased to an average of 57.45%, while the proportion of peak electricity consumption decreased to an average of 12.41%. The daily electricity costs were reduced by 5.28% compared to direct heat pump heating. With the same thermal storage capacity, application of suitable operation scheme increased COP by 21.76%, reduced electricity consumption and operating costs by 5.69% and 13.50% respectively. Increasing the capacity to 150 kW• h can further reduce operating costs by 10.04%.INDEX TERMS Air source heat pump, phase change heat storage, heat load transfer, economy, operation optimization.