Solar cells 'hairy' with nanowires could push back efficiency limits
© Niels Bohr Institute
Researchers at the Niels Bohr Institute in Denmark and the École Polytechnique Fédérale de Lausanne in Switzerland have shown that nanowires - cylindrical structure with a diameter of about a 10,000th of a human hair - have some very interesting properties that could help create solar panels that are more efficient than was previously thought possible.
It turns out that the nanowires naturally concentrate the sun's rays into a very small area in the crystal by up to a factor 15. Because the diameter of a nanowire crystal is smaller than the wavelength of the light coming from the sun it can cause resonances in the intensity of light in and around nanowires. Thus, the resonances can give a concentrated sunlight, where the energy is converted, which can be used to give a higher conversion effeciency of the sun's energy, says Peter Krogstrup, who with this discovery contributes to that the research in solar cell technology based on nanowires get a real boost. (source)
The researchers think that this technology could help push past current efficiency limits with this type of solar cells, though it's too early to tell exactly by how much and when such solar cells could be commercialized. We're at least a few years away from that, if unexpected roadblocks aren't encountered first.
Still, it's very interesting to see such much R&D effort being put into squeezing more efficiency out of solar panels, and how we keep finding new ways to make better photovoltaic panels. Not all approaches have to succeed for progress to be made, and even just by incrementally improving current technology and making it cheaper via economies of scale and more efficient production processes we could power a significant portion of our civilization with solar power. We just need to keep scaling up.
This isn't the first interesting nanowire solar R&D project. We wrote about another one a few years ago: Hairy Solar Panels Could Result From Nanowire Breakthrough.