Characterization of Electrodynamic Screen Performance for Dust Removal from Solar Panels and Solar Hydrogen Generators

The direct solar energy conversion in gigawatt scales by photovoltaic, photothermal, and photoelectrochemical processes is of national and global importance in meeting energy needs. Dust depositions on solar panels and solar concentrators cause efficiency loss from 10% to 30% depending upon the surface mass concentration of dust requiring manual cleaning with water. Such a cleaning process is expensive for large-scale installations where water is scarce. Transparent electrodynamic screens, consisting of rows of transparent parallel electrodes embedded within a transparent dielectric film, can be used for dust removal for their application as self-cleaning solar collectors. When the electrodes are activated by phased voltage, the dust particles on the surface of the film become electrostatically charged and are removed by the traveling wave generated by applied electric field. Over 90% of deposited dust is removed within 2 min, using a very small fraction of the energy produced by the panels. No water or mechanical movement is involved. An analysis of the electrodynamic removal mechanisms based on electrostatic and dielectrophoretic forces opposed by the adhesion forces due to van der Waals and image forces is presented.