Transparent Solar Cells Make Any Window Generate Energy

Tapping into solar energy at home currently means having rooftop solar panels installed, or if Elon Musk gets his way, solar tiles. But Michigan State University (MSU) has other ideas. It wants homes to generate lots of solar energy, but without the rooftop modification.

How can you add solar power generation to a building without it being visible? You use transparent panels of solar cells positioned over each window. 

According to Richard Lunt, the Johansen Crosby Endowed Associate Professor of Chemical Engineering and Materials Science at MSU, it could replace rooftop solar:

“We analyzed their potential and show that by harvesting only invisible light, these devices can provide a similar electricity-generation potential as rooftop solar while providing additional functionality to enhance the efficiency of buildings, automobiles and mobile electronics.”

The benefits of transparent solar are clear (sorry!). Adding a transparent panel over an existing window is easier than installing a frame and heavy panels on a roof. It looks better because it's an almost invisible system, and if something goes wrong with a panel then the replacement will likely be something the homeowner can carry out without help.

Each panel is a transparent luminescent solar concentrator constructed from plastic-like material containing organic molecules developed by the team at MSU. They absorb non-visible wavelengths of sunlight which get passed to very thin photovoltaic strips at the edge of the panel and generate energy.

Transparent solar isn't new, but the best on the market today are colored as opposed to completely transparent and have a conversion efficiency of seven percent. MSU's transparent panels achieve above five percent efficiency, and while they'll never match non-transparent panels, they can be used in many more places. So what they lose in efficiency they can make up for in coverage.

Now imagine those transparent panels added to every sheet of glass in a skyscraper, and every home or car window, and you can see the potential for invisible energy generation. MSU is also keen to point out any screen we use could also employ this solar tech, including the smartphones we all carry around.