Solar power is a great energy source. It’s green, and once the infrastructure is installed, it’s free. For a lot of people, though, the cost and bother of having solar panels installed on a house or a building keeps them from taking the solar plunge. But a joint project by researchers at The University of Milan-Bicocca (UNIMIB) in Italy and researchers at the Center for Advanced Solar Photophysics (CASP) of Los Alamos National Laboratory may be about to change that entire equation. They have created an inexpensive process that could allow any window or piece of glass facing on a building to be used as a solar panel.
This idea is not new. There have been other technologies that have been capable of doing the same thing. Mainly these designs have relied on a layer of plastic embedded with micro solar collectors that can be added to a window. But this concept never made it out of the lab for several reasons. First the mini solar collectors were made out of some highly toxic materials. So, if the windows ever needed to be changed, or if the building was demolished, suddenly contractors would have a toxic containment problem on their hands. Producing these windows is also fairly expensive, and the addition of the mini solar collectors tints the glass, instead of allowing it to be clear like standard windows are.
The new design does things a bit differently. Instead of coating a pane of glass with what are essentially tiny solar panels, the Italian and American researchers have put the photovoltaic element in a thin strip that goes around the edge of the window. Embedded in the glass itself are very small pieces of non-toxic metal that, instead of absorbing sunlight, redirect the infrared portion of it toward the photovoltaic edge of the pane. This makes producing them inexpensive and no more dangerous than making a standard window pane. It adds no tint to the window, and there’s an extra added benefit: Infrared light is mainly responsible for heating up the inside of a building when it comes through a window. But since these windows redirect the infrared portion of the sunlight that passes through them to the photovoltaic strip around their edges, much of the infrared energy never makes it through these windows, meaning installing them could drastically cut the amount of energy required for cooling.
So, even though this new type of glass doesn’t produce as much electricity as a standard solar panel, they’re a fraction of the cost, and just think about how many windows there are out there. Imagine if each one of them was generating carbon-free electricity all day long.