Konarka Technologies Inc of the US exhibited a variety of organic thin-film solar cell modules manufactured by roll-to-roll process at the 2nd International Photovoltaic Power Generation Expo (PV EXPO 2009).
Taking advantage of their flexibility, some prototypes are attached to a bag and used as a power source of an electronic paper in the exhibition.
Konarka's organic thin-film solar cells feature an energy conversion efficiency of 4% in a building and 3 to 4% outside a building, according to the company. The outdoor efficiency is slightly lower because "their high circuit resistance impacts more as current increases," said a spokesperson of Toppan Forms Co Ltd, which shares the booth with Konarka.
Konarka also exhibited translucent solar cells.
"The exhibited products are translucent, but we have already developed totally transparent solar cell modules," said John Gui, Konarka's vice president, Business Development, Asia. "We will release them at the end of 2009."
However, he declined to comment on the energy conversion efficiency of the products.
Furthermore, Konarka developed a fiber-type solar cell though the product was not exhibited this time. It is possible that bags and clothes interwoven with this fiber will be released in the future, the company said.