Really Green Power

Researchers have discovered that they are able to measure and attain electrical power found in plants, primarily trees. Although the millivolts that plants produce isn't nearly enough to power most of our electronics today the Univeristy of Washington is working on new technologies that could tap into that energy source.
"Tree power is unlikely to replace solar power for most applications, Parviz admits. But the system could provide a low-cost option for powering tree sensors that might be used to detect environmental conditions or forest fires. The electronic output could also be used to gauge a tree's health" (http://www.sciencedaily.com/releases/2009/09/090908151330.htm) Looks like we'll have to wait a little longer until we can charge our cell phones at our local street tree.