Solar cells need to be more dull

Solar cells may have a bright future, but to really increase their efficiency we should make them look dull.

Solar cells may have a bright future, but to really increase their efficiency we should make them look dull. Engineers are not interested in producing gleaming new solar panels and the familiar lustrous deep blue of silicon solar cells has to change...A new approach to the reflection problem has just been suggested by Shawn-Yu Lin's team at the Rensselaer Polytechnic Institute in Troy, New York...The top layer of their coating is silica-rich, with successive layers progressively richer in titanium dioxide towards the bottom. That produces a gradient in refractive index between air and the underlying solar cell, so photons are much less likely to bounce. The precise gradient in refractive index is impressive, says Keith Barnham [Physics], a photovoltaics researcher at Imperial College London. But he wonders whether the cost of achieving it is too great for commercial use.

http://www.newscientist.com/article/dn16018-solar-cells-need-to-be-more-dull.html