In recent years there has been considerable progress in the development of photovoltaic (PV) capture of solar energy from window glass. Eschewing fields of solar collectors, this technology seeks to make every window and glass wall capture light and generate electricity. If this can be done efficiently, then every window in every building can provide electric power for its inhabitants. Cool!
As Andrew Silver reports, the basic idea is to apply a coating that is excited by light, and feed that voltage to the edge of the windowpane, where it is accumulated and can be used. This has been tried with dyes (i.e., tinted windows in which the tint generates electricity), but attention has turned to quantum dots.
A team from Los Alamos National Lab have published a promising approach which extends earlier work to use an inexpensive process to deposit a film of quantum dots onto ordinary glass. These devices are tuned to capture quite a bit of the spectrum of sunlight, which generates a trickle of electricity. (Actually, the process is complicated: high energy photons are captured, generating electrons, which hop out and generate low energy photons, which propagate to the edges of the glass.)
This technology is still in the lab, but it is very interesting because it is simple, cheap, and rugged, and therefore something that could realistically used in mass production.
This is also notable because it demonstrates that nanoscale devices (quantum dots) can be used over a wide area (a windowpane). Cool!
- Hongbo Li, Kaifeng Wu, Jaehoon Lim, Hyung-Jun Song, and Victor I. Klimov, Doctor-blade deposition of quantum dots onto standard window glass for low-loss large-area luminescent solar concentrators. Nature Energy, 1:16157, 10/10/online 2016. http://dx.doi.org/10.1038/nenergy.2016.157
- Andrew Silver, Quantum-Dot Coating Could Pull Solar Energy From Your Windows, in Energywise. 2016. http://spectrum.ieee.org/energywise/energy/renewables/quantum-dot-coating-could-pull-solar-energy-from-your-windows