Transparent solar panels -- think about it for a moment: Sheets of glass or transparent plastic films that also generate electricity.
The concept of transparent solar panels isn’t new, of course, but it now looks like they’re finally finding their way to market: Ubiquitous Energy, a startup that was spun off from MIT last year, is developing a technology and patent portfolio and hopes to bring affordable transparent solar panels to market soon.
At this point, you might be wondering how transparent solar cells actually work — after all, if it’s transparent, how can it absorb light energy? The simple answer is that light energy comes in many frequencies (colors), but as far as we humans are concerned, it is only the visible wavelengths — from blue, through green and yellow, to red — that really matter. The Sun, however, pumps out a huge amount of infrared light, and some ultraviolet light — both of which are invisible to the human eye, but which can also generate large amounts of electricity if captured by a solar cell.
The trick, then, is creating a solar cell that only absorbs IR and UV radiation, while letting visible light pass straight through. According to Technology Review, Ubiquitous Energy’s transparent solar cell is built up from a series of organic layers on glass or a flexible film. We don’t know the exact nature of the organic materials being used, but other organic solar cells generally use organic polymers that might’ve had their molecular makeup altered to absorb specific wavelengths of light. There are other ways of building transparent solar cells, though: As we reported last year, researchers at UCLA and UC Santa Barbara made a flexible, high-efficiency cell from a mesh of transparent, photovoltaic silver nanowires.