As long ago as March of 2008, research has been surfacing from various institutes working on what can only be described as solar ink. Konarka Technologies Inc showed its offering as an organic ink able to be printed on several surfaces which before were unusable due to their lack of compatibility with inorganic semiconductors.

This month, researchers at the University of Texas at Austin have published work with another type of printable photovoltaic ink. Rather than being organic molecule-based, the UT group's ink uses a copper indium gallium selenide (CIGS) nanopartical solution. The CIGS solution is both less expensive to manufacture than silicon-based inks and environmentally friendly.

Thus far the researchers have produced prototype cells that produce electricity at about 1% efficiency. This is far too low to be commercially viable and the intent is to push the number to 10% efficiency, bringing the ink up to par.

The inks can be applied to various surfaces by simply painting them on. Konarka touts an inkjet printer process, while UT's ink can simply be sprayed or roll printed on several surfaces, including plastic and stainless steel.

Another interesting property of the UT inks are that they are semi-transparent after the printing process. This could lead to layers of the photovoltaic in innocuous places like skylights or tinted car windows. Or perhaps, combined with new University of Illinois flexible LED technology, could be used to create self-powered display systems for any number of practical applications.