Wrinkled solar cells increase efficiency

While scientists worldwide work to develop novel materials to increase photovoltaic solar cell efficiency, researchers from the Loo Lab at Princeton University are working to increase the efficiency of materials we already have. To do this, the researchers copy a simple solution that is already a fundamental part of one of nature's best solar collectors: leaves. By putting small folds or wrinkles in photovoltaic surfaces, the group has been able to increase photovoltaic solar cell efficiency by as much as 47 percent. "On a flat surface, the light either is absorbed or it bounces back," said Loo, "By adding these curves, we create a kind of wave guide. And that leads to a greater chance of the light's being absorbed." This folded structure is possible using flexible photovoltaic cells, which have previously been too inefficient to compete with rigid silicon-based technologies.