Houses and office buildings account for 75% of electricity use and windows of these buildings leak energy, so in order to make them energy efficient we need to plug this leak and anything we can do to mitigate that is going to have a very large impact.
A solution in site and is doable, is to turn these windows into Solar Panels.
The new solar window technologies, absorb almost exclusively invisible ultraviolet (UV) or infrared light. That leaves the glass clear while blocking the UV and infrared radiation that normally leak through it, sometimes delivering unwanted heat.
Most solar cells, like the standard crystalline silicon cells that dominate the industry, sacrifice transparency to maximize their efficiency. The best silicon cells have an efficiency of 25%.
Meanwhile, a new class of opaque solar cell materials, called perovskites, are closing in on silicon with top efficiencies of 22%. Not only are the perovskites cheaper than silicon, they can also be tuned to absorb specific frequencies of light by tweaking their chemical recipe.
Another approach to clear solar windows relies on so-called luminescent solar concentrators. In these windows, quantum dots, which are tiny semiconductor particles, absorb light at UV and infrared frequencies and re-emit it at the wavelengths that traditional solar cells capture. The re-emitted light is concentrated and shunted sideways, through the glass, to solar cell strips embedded in the window frame.
Because quantum dots are cheap to make and only a small amount of solar cell material is needed to capture the re-emitted light, these solar windows promise to be inexpensive.
We are yet not sure which technology will end up on top. One factor will be toxicity: Glass breaks, and many solar window technologies contain a small amount of toxic materials.
The technologies also have to be durable enough to last decades, as demanded by the building industry. But it’s a safe bet to expect that future buildings won’t draw all their power from the grid. They will generate it, too.
Reference- Wikipedia, Michigan State University Press,