Most people are familiar with the space-like, glassy solar panels used to generate electricity from the sun’s rays. But did you know that solar panels also come in spray-on form?
Looking back in time
Spray-on plastic solar cells first came about in 2005 and, at the time, was a huge leap for photovoltaic technology. This is because traditional silicon solar panels transformed only visible light into electricity and thus, could only operate on sunny days. In contrast, the new plastic solar cells convert both visible and infrared light – which includes thermal radiation produced by warm objects – into electricity. With the full spectrum of light being used to generate power, these new solar cells can effectively operate even on a cloudy day and use about 24% more of the sun’s radiant energy than traditional solar panels.
How plastic solar cells work
Plastic solar cells use a mixture of copper, indium, gallium, selenide (CIGS) to absorb light from the environment. Using nanotechnology, tiny crystals of this mixture are sandwiched between metal contacts that “extract the charge” out of the particle. These “sandwiches” are then added into a solvent creating a composite that can be sprayed onto any object.
The thin, spray-on solar panels are more flexible and less prone to breakage, opening up a whole host of applications for the product.2 Imagine all the everyday objects around you that can be turned into electricity generating devices – shingles on roof tops, tinted windows, sides of buildings, cars and possibly even the shirt on your back.
Getting to market
Various companies around the world are racing to bring this technology to market. Currently, spray-on solar panels are only about 3% efficient and according to Brian Korgel, a chemical engineer from The University of Texas at Austin, at least 10% efficiency is needed to make it commercially viable. Researcher Jillian Buriak at the University of Alberta in Canada hopes to see spray-on solar panels available to consumers by 2015.
Printable solar cells: http://web.mit.edu/newsoffice/2011/printable-solar-cells-0711.html