Waste Heat And Solar Cooling / Heat Pump Technology Research And Development

In this paper, the characteristics of the open heat pump system driven by solar energy using air as heat carrying medium are discussed. The heat pump cycle is modified based on the original open cooling cycle and on the operating characteristic of the heat pump with thermal energy storage in winter. The characteristic of the system in steady situation and the factors which influence on heating and COP (coefficient of performance ) are analyzed.At the same time,taking three typical districts, Beijing, Xi'an and Lanzhou, according to its weather conditions the energy storage of the heat pump cycle for a whole day is calculated in detail.In order to make it clear that the weakness parts of interior system in circulation,energy loss caculations and comparison both in cooling cycle and in heat pump cycle are present,economical budget is also discussed.By researching ,it is found that the COP of the heat pump cycle in winter is higher than that of the refrigeration cycle in summer.lt can provide a certain heating and humidity requirment for the building when using as a heat pump and the performance is quite stable too. The energy efficiency of the refrigeration cycle is higher than that of the heat pump cycle, further more, the proportion of the energy losing of the two cycles is generally identical. In particular the loss of the generator ,the absorber and the solar energy collector determined the most parts of the energy loss of the whole cycle. At the same time it is also found that as for the system using of solar energy ,the returning time of the investment accords with demand and has some popularization value through its economical discussion..But because of environmental factors and the thermal collector.the heating which heat pump system can provide at night is a little insufficient,especially in frigid regions,requiring for taking some additional measures;and low temperature water above 10 Celsius degree must be available when using as heat pump;the energy loss of the generator, the absorber is rather great ,needing to optimizing its designation to enhance its performance and energy utilization;compared this system with general air conditioning system with the absorption pair of lithium bromide and water in economy ,it costs higher,and not economical for civil use,so making great efforts to decrease the area of the solar energy collector is a mostly aspect of reducing its cost.