Study Of Personalized Optimum Tilt Angle Of Flat Solar Receivers

As the most abundant regenerated energy source,solar energy is attracted more attention and studied by researchers in the world these days.Flat solar receiver,a relatively simple and widely used solar appliance,is normally installed with a fixed angle.A solar receiver will receive different amount of solar energy if its fixed angle changes even though other factors like installed plot,weather condition and irradiance remain unchanged.On the basis of this,titled angle of receiver affects the performance and total cost of a solar energy system.To optimize the performance of solar receiver,a number of researchers managed to optimal angles which were suggested be applied in their countries.In fact,to optimize titled angles for flat receivers,solar irradiation of the following year should be obtained in advance because in recent several decades,climate has been changing and the warming trend proved to be so significant that it can not be ignored.Considering the randomicity and the changing trend of climate,NN is used to forecast solar irradiation for optimizing flat solar receiver tilted angle.Multi-factors cause the collectable irradiation on the ground to be random.Thus, Elman NN is used for forecasting the nonlinear solar irradiation.Here,monthly solar radiation including global radiation,sky radiation and direct solar radiation are forecasted.The solution of monthly,yearly,and half year optimum tilted angles is obtained, modeling of solar receiver tilted angle optimization as the accumulative total solar irradiance being the objective.In this article,solar irradiation in Beijing is used for optimizing tilted angle in different time intervals.Three sets of solar irradiation are used for comparison:real data,data of the following year forecasted by NN and data of the typical meteorological year(1971～2000) in the web China Meteorological Data Sharing Service System.Based on the recorded solar irradiation in Beijing,2003,the present research compares 3 sets of optimal angles,viz.monthly optimal tilted angles, half-yearly ones in summer months and winter months and yearly one.They are calculated by typical meteorological data and forecasted data in 2003.Furthermore, the collected solar irradiation is calculated.Concrete results are calculated and are suitable for application in China.Otherwise an inquiry interface is made up based on VB software.