Research has shown that the avalanche effect can occur in semiconducting crystals and thus be used in solar cells to increase energy conversion efficiency. This discovery could ultimately lead to new processes in solar cell production that could reduce costs as much as 25%. A full story on this topic is set to be published in Nano Letters this week but for the time being we’ll break it down for you…
Currently most solar cells only create about 15% energy efficiency in output and are thus a relatively expensive option for power production. Low efficiency creates the need for more solar panels to fully power a home or business. This inefficiency in energy conversion is compounded by the rising costs of silicon and the expense of shipping heavy glass and metal. Large solar “farms” or “arrays” could be created to reduce the shipping costs but electricity is lost as it travels over long distances, so the best solution is a distributed network of solar power stations or home mounted panels, but this leads us back to the shipping cost problem. Breakthroughs in production by companies like Nanosolar certainly help in terms of shipping and production costs (they print solar ink onto thin lightweight metal sheets), but through the application of the avalanche effect, energy efficiency of solar panels could rise to a level of 44%!
This jump in efficiency alone is enough to make solar affordable for the masses, even with the old heavy technology, but when combined with thin film technology it could create an even more rapid transition to worldwide solar use. The avalanche effect was first measured in 2004 but had been doubted and unproven until recently when Prof. Laurens Siebbele demonstrated that it can occur in lead selenide (PbSe) nanocrystals. More details regarding Professor Laurens and the Avalanche Effect can be found at the Foundation for Fundamental Research on Matter website. We’ve posted a picture of the process from the FOM website below for all you solar engineering geeks:+
