Transparent solar panels?
Researchers at Michigan State University have developed the first transparent and rigid solar concentrators. This invention could, in time, enable our windows to create energy.
Up until now, experiments in the field had led to rather inconsistent results, particularly in energy production. Additionally, the materials produced were not completely transparent, but either brightly coloured or too dark and could not be used as windows or screens as a result.
These new luminescent solar concentrators (LSC) are "transparent": according to Professor Richard Lunt, his team of researchers aimed at developing a transparent "active luminescent layer", even if smaller yields were obtained.
The solar energy harvesting system uses small organic molecules that absorb specific nonvisible wavelengths of sunlight. The molecules act as a sort of filter that only keeps the invisible spectrum of sunlight, namely ultraviolet and infrared.
Specifically, light is harvested by the special plastic from which the panel is made and then redirected to the thin photovoltaic cells lodged inside the panel's frame. The photovoltaic cells convert the harvested light into energy.
Richard Lunt explains that "…because the materials do not absorb or emit light in the visible spectrum, they look exceptionally transparent to the human eye". However, the transparency renders the mechanism slightly inefficient, with solar conversion yields of slightly less than 1%, as opposed to the 7% obtained through coloured LSC.
The team believes that there are many future applications for this technology: "It opens a lot of areas to deploy solar energy in a non-intrusive way […] It can be used on tall buildings with lots of windows, car windshields, smart phones and tablets. Ultimately we want to make solar harvesting surfaces that you do not even know are there".
Their goal is simple: increasing the solar conversion yields to 5%. If they are able to achieve their goal, their innovation could be mass-produced extremely quickly at a relatively low cost!
More information
http://spectrum.ieee.org/energywise/green-tech/solar/can-solar-power-go-truly-transparent