| Solar-assisted heat pump can’t work at nights and in consecutive rainy days due to the intermittency, instability and volatility of solar energy. The solar-assisted heat pump system combines with phase change energy storage technologies to improve the shortages of the system. A novel solar energy storage/evaporator/collector is proposed, integrated solar collector, energy storage and evaporation, which integrates with solar collector, energy storage containers and evaporator to collect solar energy and release it during nights or consecutive rainy days. The collector is also capable of improving evaporation temperature, thereby enhancing the coefficient of performance of the heat pump system. At the same time, the integration of solar collector, energy storage containers and evaporator makes the system structure more compact, reducing the intermediate heat transfer and saving the manufacturing costs.This paper uses Fluent to simulate the temperature field and liquid fraction of PCM during energy storage and release process. The results show that the temperature is gradually reducing from the wall to the center, the liquid region continues expanding as time increasing during energy storage process. The sunny side has the highest temperature,and the increasing rate of temperature of other locations increases with time. The liquid region expands from sunny side to shady side and inner with time increasing.The comparative experimental study was made on heat collector performance and energy storage characteristics when the storage/evaporator/collector was filled with different PCMs. The relationship between η and (Ts-Ta)/Iwas got. The comparative experiments were made when the tubes were respectively filled with water, deconate and paraffin. The results show that using paraffin and deconate as energy storage materials can achieve peak load shifting of solar energy to ensure the all day working of the system.The system performance were investigated when filled with different PCMs decanoate or paraffin in transitional season in Nanjing. All the results are listed as follows:the heat got efficiency of the system in rainy days was obviously higher than sunny, and the system filled with paraffin had a greater heat got efficiency compared to the system filled with decanoate; the coefficient of performance of the system using paraffin was higher than that one using decanoate under similar wether conditions, furthermore, it was stability and practically unchanged when the wether changed in similar conditions,the instantaneous coefficient of performance of the system filled with paraffin is higher than the system filled with decanoate during the day and night. When PCM is paraffin, the system has a higher heating rate.
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