It’s 2014. Instead of hiring workers to install solar panels on your roof, you spray solar ink all over the rooftop and sun-facing walls of your home. It’s not science fiction–it could be reality in three to five years according to Brian Korgel of the University of Texas at Austin. The chemical engineering researcher and his team have developed spray-on solar cells using nanoparticle “inks” made of copper indium gallium celenide that are 10,000 times thinner than a single strand of human hair.
There’s still plenty of work to be done before the solar ink can be commercialized. Right now, prototypes only convert 1% of absorbed sunlight into electricity, but the cells aren’t viable until they convert 10% or more. Even then they have a ways to go–some existing panels are over 25% efficient. Once the solar ink is ready for commercialization, Korgel and his company Innovalight will use a newspaper-like process for production with nanocrystals sprayed on spools of plastic or metal foil.
Silicon-based ink is already in production, but the new nanoparticle ink requires lower temperatures, less material, and is cheaper to produce. So cheap, in fact, that Korgel imagines it won’t be long until the semi-transparent ink can be used to create windows that also act as solar cells.
[Correction: Although Brian Korgel co-founded Innovalight, that company is not involved in his current project at the University of Texas at Austin.]