Acoustic levitation is a way of using sound waves to move small objects. If you reflect the sound waves and manage to get them working together on all three axes (x,y and z) then you can levitate an object, like in the video above. Scientists believe that this is a great way to clean the dust away from the solar panels of Martian rovers. “The team tested the system on a solar panel coated with mock lunar and Martian dust. The output of the clean panel was 4 volts, but when coated with dust it produced only 0.4 volts. After four minutes of acoustic levitation treatment the output returned to 98.4% of the maximum.”
Basically, all you need is a normal speaker capable of creating a high pitched noise and a sound reflector to reflect the sound back and create a standing wave. We only need to move the dust on one axis. When the dust ‘lifts off’ it gets blown away by the wind. Imagine an endless farm of screaming solar panels. It’s a scary thought, but it could be a great innovation.
One of the main problems with having a giant solar farm here in Kuwait is that the panels will be coated with dust all year long. It would be very hard to keep them clean and working at full capacity. The acoustic levitation technology is cheap and uses readily found parts. The speaker and the reflector would probably not be attached to the panels themselves. I’d imagine they would slowly move under and over the panels on a fixed track, cleaning as they move along.
When I visited Masdar a few weeks ago, dust accumulation was one of the main problems they had with their solar tests. Most of the panels never reached the levels they were capable of even when the sun was beating down. I don’t know if it makes sense economically, but it seems like the idea is worth exploring further.