University of Michigan researchers have invented the world’s first fully transparent solar cell. The new system is exciting because it offers energy generation, with no compromise in visibility.
The development opens up a wide are of use. Think of all the glass skyscrapers that could harvest incoming solar and yet offer great view. Smartphones could charge up while you are using it outdoors.
Previous attempts to develop transparent solar cells have meant the glass has been to dark. As you can see in photo, their system is fully transparent. That’s because the glass itself is not a solar cell – it’s a transparent luminescent solar concentrator. It is made of organic salts tuned to only absorb ultra-violet and infrared energy, the kind of light frequencies you can’t see. The salt then luminesce at another infrared frequencies that gets picked up by tiny plastic channels that line the edges of the “glass” and direct the infrared rays to tiny conventional solar cells.
At the moment it is still just an innovation, which is not yet efficient or affordable. According to the paper, the TLSC has a rated efficiency of 1%, but the researchers think 5% should be possible. Non-transparent luminescent concentrators (which bathe the room in colourful light) max out at around 7%. Left alone, this doesn’t seem like much, but multiplied by every window in a building this could add up to power the LED lights in rooms, for instance.