Free Deposition of Dust on Inclined Solar Batteries
Abstract
The problem of deposition of dust particles with sizes of large wavelengths of the photoactive part of solar radiation on solar batteries (SBs) is considered. Under the assumption that dust particles in the air do not collide and are deposited on the SB in one layer, formulas are obtained to determine the area of shading of the SB by dust particles in time. These dependences also take into account the size of dust particles, their concentration in air, the angle of incidence of sunlight and the angle of inclination of the SB to the horizon. It is shown that the shading area changes in time mainly linearly, but also has a nonlinear daytime component, which depends on the angle of incidence of sunlight on the SB. The influence of the angle of incidence of the rays on the shading is already noticeable at angles of more than 200. The formulas obtained make it possible to estimate the dynamics of shading of the SB by solid particles of dust and to estimate the frequency of its cleaning from dust (at a given power loss). So, even with standard levels of concentration of dust particles with dimensions of 2.5 and 10 microns and an admissible drop in power of the SB by 5%, the frequency of the SBs cleaning is only about 30 days. The results of the study show that when determining the optimal angle of inclination of the SB, it is necessary to take into account the dust factor. The obtained dependences can also be used to assess the dustiness of flat transparent enclosures of solar installations.