Has Michigan State University (MSU) cracked the see-through solar debacle? Maybe. Companies and universities have been working for years to develop see-through or transparent solar panels. If they’ve realized a transparent solar photovoltaic device that’s efficient and inexpensive they could open up all sorts of possibilities, from windows that power a building or home to smartphone screens that power the device while your looking at it in the sun.
The research at MSU has led to a new type of solar concentrator that can be placed over a window to create solar electricity. The device is called a transparent luminescent solar concentrator. The concentrator uses small organic molecules that absorb specific nonvisible wavelengths of sunlight.
“We can tune these materials to pick up just the ultraviolet and the near infrared wavelengths that then ‘glow’ at another wavelength in the infrared,” said Richard Lunt a assistant professor of chemical engineering and materials science at MSU’s College of Engineering, who led the research. That glowing infrared light is then channeled to the edge of the layer where thin strips of photovoltaic solar cells convert it into electricity. The materials don’t emit or absorb visible light so they appear transparent, according to Lunt.
Other organizations focussed on transparent solar power have used a variety of methods, including thin strips of PV devices in a plastic layer, but these can reduce transparency. For instance the University of California, Los Angeles recently moved toward commercialization of a transparent PV device it’s been developing.
"It 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,” Lunt said. “Ultimately we want to make solar harvesting surfaces that you do not even know are there.”
Still, one thing plagues most of these efforts—efficiency. Many transparent solar devices remain in the 1 percent efficiency range—UCLA’s can convert about 7.3 percent of the sun’s light into electricity. MSU’s device is still among 1 percent efficient at this point, but Lunt anticipated that the device could be optimized at about 5 percent efficiency.Tweet