The goal at the end of the rainbow is to capture the pot of gold. In the case of solar PV, it is to increase the efficiency of light-to-electricity conversion. A scientist at MIT, Dr. Peter Bermel has a totally new concept of increasing the conversion process. He and his colleagues have invented a way of concentrating the energy in the sun’s rays without the need for mirrors. It is, quite literally, a suntrap. Their concept has been published in in Nanoscale Research Letters and is had to describe. The following is a story taken from The Economist dated December 31, 2011.
Dr Bermel’s proposed trap is a thin sheet of tungsten (a heat-resistant metal) that has been processed in quite a complicated way. One surface, which faces the sun, is covered in microscopic pits. The other, which faces a specialized type of solar cell made of a material called indium gallium arsenide, is sculpted into a structure called a photonic crystal that causes it to emit infra-red radiation selectively at the frequency best absorbed by the cell. Both of these surfaces would be created by photolithography, the process used to make computer chips. According to Dr Bermel’s calculations, would be a system that converts 37% of sunlight into electricity. This compares with a maximum of 28% by standard silicon-based solar cells that have not had the incident light concentrated by parabolic mirrors.
Renogy LLC—a Louisiana based solar panel manufacturer, is one of the two solar panels suppliers for Lamar Advertising’s “Renewable Louisiana” Project. Lamar and Renogy have begun with a 30KW installation, and look forward to a successful trial. Renogy solar panels will be incorporated onto many of Lamar’s billboards throughout the state, returning energy to the grid during peak consumption hours. “Incorporating Renogy’s products onto billboards containing LED lighting will definitely help Lamar save on energy costs. Besides, our products’ high PTC rating plus efficiency will allow Lamar’s billboards to solely rely on renewable energy”, said Yi Li, president of Renogy. “Our products are a perfect match for such a novel combination, and we are more than happy to participate in such a significant project that sets the bar for Louisiana’s green movement”.
full article here
(comment from TSEA: With the reduction of federal and state support of solar systems, the industry needs to look for the boutique applications that can take advantage of providing power to applications that are either isolated from the commercial power grid, or provide a more economical package that is free of monthly power bills. I will have a paper on boutique applications for paid members this month. The paper covers all vistas of potential applications of solar PV. We need to build our membership so join us and keep our organization going.)