[Sparky168]

Cheap solar cells.
http://www.forbes.com/sites/jenniferhicks/2012/02/21/grass-grass-clippings-turned-into-solar-cells-by-mit-scientist/

 

[ct-fiskerbuzz]

Hm. They'll have to bring the efficiency up 100x (from 0.1% to 10.0%) to compete with conventional PV.

 

[Sparky168]

Hm. They'll have to bring the efficiency up 100x (from 0.1% to 10.0%) to compete with conventional PV.

You are right. That was more of a novelty.

Here is a 28.3% efficiency with a flexible backing.
http://www.technologyreview.com/energy/39649/