A number of physicists at the Los Alamos National Lab are attempting to create or rather perfect intelligently designed glass that doubles as a ‘transparent’ solar panel or more accurately a luminescent solar concentrator. Effectively, this means that if they succeed in creating an efficient product, we could see photovoltaics in every high rise, residential home or even vehicle.
What's most interesting about this breakthrough technology is that it is not actually what one could call a ‘Solar Panel’ or at least it is not a solar cell. The glass itself doesn’t harvest electricity from the sun directly, at all. In fact, the word transparent literally means that all the light that hits a surface, or the majority, is not actually absorbed by a material but rather refracted through it uniformly. Yet this specially engineered glass can be programmed to absorb certain frequencies of light. This is possible because the glass is infused with quantum dots, which are essentially nano-sized metallic crystals. These quantum dots refract light in a very unique and essentially customizable way. They have the ability to systematically absorb and then re-emit only infrared, or in some cases both infrared and ultraviolet, wavelengths of light while allowing the visible light spectrum to pass through unchanged to the human eye. This refracted light is then redirected to the glass’ edge, which is lined with efficient solar cells. By using solar concentrators over ‘transparent panels’ (which are often just windows with patterned solar cells partly covering the surface) the team is able to achieve true transparency while generating usable electricity.
Unfortunately, you won't be able to simply switch out the 10 windows around your home and become energy independent. Due to the fact the glass only separates a small fraction of the light which is normally absorbed by your standard rooftop solar panel, they have a much lower efficiency rating. Quality rooftop solar panels are getting closer to being able to convert sunlight at an efficiency of up to 20%. Standard solar concentrators will only be ably to produce power at peak of around 7% at the theoretical maximum. Yet in reality, commercial transparent solar doesn’t even come close. Ubiquitous Energy’s Smart Glass currently operates at around 1% efficiency. However, they are hopeful in being able to achieve an admirable 10% efficiency rating in the future, and we hope that they can make that a reality. What is most exciting about Smart Glass is that it actually comes as a ultra thin film, at around 1/1000th of a millimeter thick, meaning in theory it could be placed on existing glass. It could even be applied directly to your smart phone. Imagine a world where phones never had to recharge, and we could simply stand in the sun. In fact, Ubiquitous Energy claims that once they make smart glass available it will be able to replace batteries in digital interfaces forever.
However, solar glass is not meant to replace rooftop solar but rather assist in creating a society which can rely solely on renewables rather than coal or fossil fuels. For example, if the One World Trade Center converted entirely to solar concentrators, the energy produced could be used to power up to 350 apartments, and that's 350 homes off the grid even if standard solar could do a better job. The potential of these types of inventions come from their ability to replace regular windows everywhere, meaning we could see millions if not billions of solar concentrators covering our buildings in the not so far future.