Scientists have found a way to create solar cells that are far more efficient using an ultra thin nano structure.
In what could be an incredible new energy breakthrough, a team of scientists from Stanford University have used nanotechnology to create low cost solar cells. It is an important discovery that, while first posited a few years ago, is getting new attention as a technology that could lead to tremendous increases in efficiency for solar power and reduce our reliance on fossil fuels.
Scientists used crystalline silicon solar cells, which are very thin, to create cells that are much more efficient when it comes to capturing solar energy. Researchers used optical modelling as well as electrical simulations to demonstrate that such a solar cell made from crystalline silicon could generate triple the power of current technologies.
The new cell is believed to trap light much more effectively, allowing it to keep the light longer which means there is a much better chance that the light gets absorbed as power. It could provide a simple method to drastically improve the efficiency of solar cells in the future.
“Crystalline silicon is an attractive photovoltaic material because of its natural abundance, accumulated materials and process knowledge, and its appropriate band gap,” reads an abstract from a paper on the subject in 2010. “To reduce cost, thin films of crystalline silicon can be used. This reduces the amount of material needed and allows material with shorter carrier diffusion lengths to be used. However, the indirect band gap of silicon requires that a light trapping approach be used to maximize optical absorption. Here, a photonic crystal (PC) based approach is used to maximize solar light harvesting in a 400 nm-thick silicon layer by tuning the coupling strength of incident radiation to quasiguided modes over a broad spectral range. The structure consists of a double layer PC with the upper layer having holes which have a smaller radius compared to the holes in the lower layer.”