Self-Cleaning Solar Panels

Dust particles that collect on solar panels and block sunlight can be shaken off with a jolt of electricity—a technique that could help keep the panels operating efficiently. Malay K. Mazumder of Boston University described a “self-cleaning” technology for solar panels, which he and his colleagues originally developed for solar panels on spacecraft. The panels are covered with a transparent screen impregnated with transparent indium tin oxide electrodes. Pulses of electricity sent through the electrodes generate waves of electrostatic and dielectrophoretic forces that literally shake both charged and uncharged dust particles off to the sides of the panels. Mazumder cited experiments showing that 4 g of dust on a 1-m² panel reduces solar power conversion by 40%. In desert regions such as those of Arizona, Australia, and India, where large-scale solar panels are common, the dust problem can be even worse. With the Boston group’s technology, a solar panel could dust itself off in two minutes using less than 10 W/m², which is only a small amount of the power generated by the panels, Mazumder said.