Dust, dirt, and the occasional bird-bomb can chip away at the efficiency of solar panels. Hand washing is fine for home-scale installations but that can add up to a huge problem for large installations that cover multiple acres of ground or roofs. Now scientists from Boston University have come up with a solution: self-cleaning solar panels based on technology used in missions to Mars.
The problem of dust-clogged solar panels is exacerbated by the tendency to site large-scale installations in desert areas, where water for washing is scarce and windswept dust can accumulate for long periods without rain to wash it away. The hunt is on for low cost, high efficiency ways to keep the panels clean without expending more energy in the process.
Dust and Solar Panels
According to Boston University scientist Malay K. Mazumder, it doesn’t take much dust to interfere with solar panel performance. Solar power conversion can decrease by 40 percent with just a fraction of an ounce of dust per square yard, and the dust deposition rate is much higher than that in many areas that are favored for large-scale solar installations.
Leading the Charge to Self Cleaning Solar Panels
Dr. Mazumder’s team worked with NASA to develop self-cleaning solar panels for space missions. They work by covering the panels with a sheet of transparent plastic or glass, which is coated with an electrically sensitive material. When sensors detect a certain concentration of dust, the charge is tripped and an electrical “wave” pushes the dust to the edges of the screen. The solar panels themselves provide the electricity for the cleaning process. A company called XeroCoat has also come up with anti-reflective solar coatings that can be deposited directly onto thin film solar panels, which are designed to resist soil and dust.
Image: Dirty window by Chloester on flickr.com.
Tina Casey specializes in military and corporate sustainability, advanced technology, emerging materials, biofuels, and water and wastewater issues. Tina’s articles are reposted frequently on Reuters, Scientific American, and many other sites. You can also follow her on Twitter @TinaMCasey and Google+.