Cleaning an array of thousands of solar panels could be done with a mini shock wave, rather than manually washing each one, according to a researcher.
Boston University professor Malay Mazumder on Monday offered details about a material that can be used to enable automatic cleaning of solar photovoltaic panels, in a presentation at the national meeting of the American Chemical Society in Boston.
Keeping solar panels clean is serious concern, particularly for large-scale solar PV farms in dusty desert areas. The build-up of dust and particulate air pollutants blocks the sun and can significantly decrease the output of solar panels.
Right now, solar farm operators clean panels with water, which is a scarce resource in sunny desert areas. Mazumder proposed an electrically sensitive coating that would be placed on the glass of PV panels or a plastic sheet. Sensors that monitor dust concentrations would send an electrical charge through the material, causing a wave to ripple across the surfaces of the panels and send dust to the edges.
Mazumder said the process, which was originally developed for moon and Mars missions, would remove 90 percent of accumulated dust in two minutes.
"A dust layer of one-seventh of an ounce per square yard decreases solar power conversion by 40 percent," he said in a statement, adding that the technique could be used in commercial or residential systems.
The growth of solar power creates a need for cleaning services and methods, particularly for large-scale installations where investors expect a certain output. For the high-tech coating and sensor system to be used by commercial energy project developers, it cannot add significantly to the maintenance costs associated with panel cleaning.