With global warming becoming an increasing threat to our civilization’s stability, cheap, low-carbon energy sources are necessary to meet rising electric power needs. Addition of solar panels to homes has the potential to take a load off the grid and power homes that are off it, but the high cost of solar panels is driving people away from using them. The solution to this problem comes in the form of a paint.
With new “paint-on” solar cells, the next coat of paint that you add to your house could generate electricity. At the University of Notre Dame’s Center for Nano Science and Technology (NDnano), researchers have created a “solar paint” that uses semiconducting nanoparticles to convert sunlight to energy. This research was funded by the Department of Energy's Office of Basic Energy Sciences.
The paint uses quantum dots, a type of nanoparticle that can produce energy. These quantum dots were added to nanoparticles of titanium dioxide coated in cadmium sulfide or cadmium selenide. The mixture was suspended in a mix of water and alcohol creating an inexpensive solar paint that can be applied to any conductive surface using traditional painting methods.
Researchers at the University of Toronto and King Abdullah University of Science and Technology in Saudi Arabia achieved the best light-to-energy conversion efficiency reached so far; 7 percent, not far behind the 10 to 15 percent efficiency of commercial silicon solar cells. Despite the lower efficiency, the reason this paint can make a difference is because of its low cost. It can be used in mass quantities and will be accessible to people who are less wealthy.
Solar paint has the potential to give everyone access to solar power to slow the effect of global warming. It can also give cheap power to people in developing countries who have abundant sun but limited access to electricity. The global solar industry is expected to grow 15.3% by 2015 according to TechNavio’s report “Global Solar Panels Market 2011-2015,” and it will grow even more if technologies like solar paint become widely used.