Scientists have shown that a single nanowire can concentrate the sunlight up to 15 times of the normal sun light intensity. The results are surprising and the potential for developing a new type of highly efficient solar cells is great.
Due to some unique physical light absorption properties of nanowires, the limit of how much energy we can utilize from the sun's rays is higher than previous believed. These results demonstrate the great potential of development of nanowire-based solar cells.
The research groups have, during recent years, studied how to develop and improve the quality of the nanowire crystals, which is a cylindrical structure with a diameter of about 10,000 part of a human hair. The nanowires are predicted to have great potential in the development of not only of solar cells, but also of future quantum computers and other electronic products.
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. This can be used to give a higher conversion effeciency of the sun's energy.
The typical efficiency limit - the so-called "Shockley-Queisser Limit" - is a limit, which for many years has been a landmark for solar cells efficiency among researchers, but now it seems that it may be increased.
Although it does not sound like much in that the limit is moved by only a few percent, it will have a major impact on the development of solar cells, exploitation of nanowire solar rays and perhaps the extraction of energy at international level. However, it will take some years years before production of solar cells consisting of nanowires becomes a reality.
This story is reprinted from material from Niels Bohr Institute, with editorial changes made by Materials Today. The views expressed in this article do not necessarily represent those of Elsevier. Link to original source.