A team of researchers at Michigan State University has developed a new type of solar concentrator that can create solar energy without blocking the sunshine. The team tons the innovative product by a key word “transparent” and calls it a transparent luminescent solar concentrator.
Research in the production of energy from solar cells placed around luminescent plastic-like materials is not new. These past efforts, however, have yielded poor results – the energy production was inefficient and the materials were highly colored.
“No one wants to sit behind colored glass,” said Lunt, an assistant professor of chemical engineering and materials science at MSU’s College of Engineering. “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 solar harvesting system uses small organic molecules developed by Lunt and his team to absorb specific nonvisible wavelengths of sunlight. Users can tune these materials to pick up just the ultraviolet and the near infrared wavelengths that then “glow” at another wavelength in the infrared. The “glowing” infrared light is guided to the edge of the plastic where it is converted to electricity by thin strips of PV solar cells.
“Because the materials do not absorb or emit light in the visible spectrum, they look exceptionally transparent to the human eye,” Lunt said.
One of the benefits of this new development is its flexibility. While the technology is at an early stage, it has the potential to be scaled to commercial or industrial applications with an affordable cost. It can be used on buildings, cell phones and any other device that has a clear surface, opening a lot of area to deploy solar energy in a non-intrusive way.
Lunt said more work is needed in order to improve its energy-producing efficiency. Currently it is able to produce a solar conversion efficiency close to 1%, but noted they aim to reach efficiencies beyond 5% when fully optimized. The best colored LSC has an efficiency of around 7%.