New Reflective Layer Boosts Efficiency of Thin-Film Solar Cells
Asia Pulse/LexisNexis, November 26, 2008
Source: Semiconductor.net
http://www.semiconductor.net/articleXml/LN890291678.html
Japan’s Sustainable Titania Technology Inc. (STi) has developed a way to boost the energy conversion efficiency of thin-film solar cells by about 20 per cent. The process involves fabricating a highly reflective film on the backside of the electricity-generating layer of the solar cell so that less light is lost.
Around 80 per cent of the sunlight entering a typical thin-film solar cell reaches the electricity-generating layer, but about 50 per cent passes completely through. A reflective film situated below this layer can bounce some of that light back inside so that more light energy can be converted to electricity.
Other reflective films developed to date can bounce back about 15 per cent of the light, but the new film developed by Sustainable Titania Technology can bounce back 17.5 per cent.
The company makes the film by coating the glass substrate with a water solution containing nanoparticles of titanium oxide, silica and semiconducting metal compounds. Although reflective, this film is also highly transparent, so it can be used with see-through thin-film solar cells. Moreover, it can be fabricated without the need for vacuum processing or heating.