Clear Solar Cells Turn Windows and Electronic Screens into Power Resources
Energy efficiency is a part of our everyday language as natural resources dwindle and energy prices rise. Solar energy, which uses large panels to collect and convert sunlight into electricity, is becoming increasingly common. Researchers at Michigan State University and co-founders of the MIT start-up, Ubiquitous Energy, are at the cutting edge of advancements in solar technology that could one day put an end to the bulky and intrusive solar panels and bring significant cost-savings to the American public. They have developed a completely clear solar cell called the transparent luminescent solar concentrator that is now on the cusp of being launched into the mass market.
Luminescent solar concentrators are not a new phenomenon. In the past, luminescent material used for solar concentrators had to be colored to capture light. This produced a stained glass
A transparent luminescent solar concentrator waveguide is shown with colorful traditional luminescent solar concentrators in the background. The new LSC can create solar energy but is not visible on windows or other clear surfaces.
appearance which served as a distraction for those living or working around windows coated with this material. Dr. Richard Lunt, research collaborator and co-founder of Ubiquitous Energy, states, “No one wants to sit behind colored glass. It makes for a very colorful environment, like working in a disco. We take an approach where we actually make the luminescent active layer itself transparent.”
The transparent luminescent solar concentrator is a clear, thin energy-producing plastic coating that can be integrated directly into anything that has a clear surface. It harvests solar energy by using organic molecules to absorb specific nonvisible ultraviolet and near infrared wavelengths of sunlight. These wavelengths “glow” at another infrared wavelength invisible to the human eye. The infrared light is then funneled to the edge of the plastic where thin strips of photovoltaic cells convert it into electricity.
Lunt maintains that this high-tech solution “opens a lot of area to deploy solar energy in a non-intrusive way. It can be used on tall buildings with lots of windows or any kind of mobile device that demands high aesthetic quality like a phone or e-reader. Ultimately we want to make solar harvesting surfaces that you do not even know are there.”
Currently, transparent luminescent solar concentrators only yield a solar conversion efficiency near 1 percent. However, Lunt and his team are continuing to make strides in improving its energy-producing efficiency. They project it will reach 10 percent once mass production begins. Alone, this may not seem like a significant number, however if transparent luminescent solar concentrators were to be installed in every window of a house or office park, the ripple effects of its benefits would be impactful.
The development of the transparent solar concentrator brings us closer to achieving a more sustainable future. This technology could empower Americans to have control over energy costs and to achieve energy independence by enabling everyday electronic devices, exterior windows of buildings and homes, greenhouses, and even automobiles, to seamlessly transform light into electricity in an aesthetically pleasing and cost-effective manner.
Featured image photo credit: Michigan State University
Post photo credit: G.L. Kohuth