Study Of Dual Heat Source Solar Heat Pump Mode

The thesis mostly analyses two heat sources of heat pump: air and solar energy. Air source heat pump, with the advantages of flexibe operation, energy conservation, high automation and convenient utilization, has been widely spreaded in china since 1990's. However two disadvantages limit its application: frost and contradiction between heat supply and building heat load in low ambient temperature. The paper introduces solar assisted heat pump (SAHP). After analyzing the problems of the application of solar assisted heat pump as heat suppy, puts forward the mode of switchable dual source solar assisted heat pump using water and air as heat source in parallel. The heat pump runs under air source when ambient temperature is high. Then it switches to water source running when ambient temperature is low. Hot water supplying water source evaporator comes from energy storage tank which stores solar energy by the solar collectors.The paper establishs the model of solar radiation, ambient temperature, solar energy flat plate collector, basic solar water heater, water source evaporator, dual source heat pump and programs the calculating and analyzing software. Simulation of one period of heat suppy can ensure required collector area, water capacity of energy storage tank, average COP and collector efficiency ect. Using bin method the paper calculates building heat load and compares required capacity of heat pump and auxiliary heater, energy consumption, load ratio, average COP and HSPF between dual source SAHP and air source heat pump. The paper concludes that dual source SAHP requires smaller capacity of heat pump and auxiliary heater, consumes less energy and has higher load ratio, average COP and HSPF.