Solar panels don’t have to be shiny black surfaces anymore

For anyone worried about aesthetics, solar panels can be a real drag. An environmentally-friendly, socially-conscious drag, but a drag nonetheless. Researchers at Fraunhofer Institute for Applied Optics and Precision Engineering IOF in Germany are working on a new type of photovoltaic using thin-film technologies to do away with the dark-colored cells and bring a little color to the panels.

The solar panels being developed at the Fraunhofer Institute are of the SIS (semiconductor-insulator-semiconductor) variety. They consist of a silicon substrate just a few micrometers thick, which absorbs light and turns it into electricity. A transparent insulator is laid over top of the silicon wafers, and a 100 nanometer thick oxide layer is deposited on top of that.

The oxide acts as the second semiconductor layer, and ensures that as much light as possible reaches the silicon wafer below. This layer is also the key to making the solar cells work in more colors. By altering the physical thickness of the transparent conductive oxide, the surface has a different optical refraction index, and thus a different color.

You might wonder if changing the color of a solar cell makes it less efficient, but the scientists behind the research say no, not at all. The cells they have been working on seem unaffected by the thickness of the conductive oxide layer. Simulated efficiency is around 20%, which is where this type of SIS cell is supposed to be.

Future versions of this technology might employ a type of inkjet printing that deposits the oxide layer with more flexibility, allowing for complex designs. Solar panels in the future might not be an eyesore. They could blend in with a roof, the facade of a building, or even be part of a beautiful architectural design.

Original Article: Here!