Biomimicry

"One of the more intriguing capabilities in nature is, however, the number of biological systems that are able to self heal. Scientists, spurred on by the potential economic benefits of materials that would be able to repair themselves  - longer lifetime, lower maintenance costs and more efficiency - have worked to develop self-healing systems for various materials, including plastics. And with success: various polymers are now available which have  the intrinsic ability to repair damage caused by usage over time. Up until now, however, composites, were a whole different ballgame. But once again, nature showed the way."

"Researchers at North Carolina State University have come up with a new way of making solar cells with a method that uses circulation much like that in plant leaves to maintain the efficiency of the cells. 

Dye-sensitized solar cells (DSSC) are organic cells that use light-sensitive dyes to generate electricity. These cells could eventually make low-cost and more environmentally-friendly collectors for solar energy, but until now, the problem has been that the dyes eventually break down due to ultraviolet rays from the sun and lose their efficiency.

The NCSU scientists have created a cell with vascular chanels, much like the veins in a leaf, to allow them to replenish the dye and thereby maintain the efficiency of the cell."