Future Cities Could Be Powered by Windows That Absorb Sunlight

Energy Made Crystal Clear

Developments in semitransparent solar concentrators could turn any window into a power source, according to a project outlined in Nature Nanotechnology. The project began at the Department of Energy’s Los Alamos National Laboratory in 2014, and the latest research shows the team making strides in reaching the necessary energy efficiency for the tech to become practical.

The project uses extremely small semiconductors called quantum dots to create sunlight-harvesting tech. Lead researcher Viktor Klimov explained that he and his team used a machine to pour a mixture of quantum dots and PVP polymer onto a piece of glass, spreading it into a thin sheet. Those nanosized dots could then be customized to select what light wavelengths to accept and what wavelengths to omit as sunlight hit the glass. This eliminated a problem encountered using organic dyes for the same purpose as those would absorb both sunlight and the light produced by the dyes.

In their latest research, the team has reported that quantum dots spread in a thin layer on normal glass could live up to 14 years with about 1.9 percent overall energy conversion efficiency. While they still have a ways to go to reach 6 percent, the point at which the devices become practical, they are making good progress.

Energy Everywhere

One of the coordinators of the project, Sergio Brovelli of the Department of Materials Science of the University of Milan-Bicocca (UNIMIB) in Italy, called quantum dot solar window tech "a potentially game-changing technology towards “net-zero” energy cities,” and he's right.

By absorbing solar energy from the sides of buildings and not just their rooftops, we could greatly increase our energy generation. Brovelli even estimates that the 12,000 windows at New York's One World Trade Center alone could power over 350 apartments.

It seems we can turn just about everything into energy-generating technology these days, from clothes to bike lanes and now our windows. With so many new developments in energy and the increasing affordability of green solutions, drawing back the curtains of tomorrow is unveiling a window to limitless clean energy.