Trees provide us with oxygen, shade, timber, and…power? That’s what researchers at the University of Washington proved recently when they ran a circuit off energy generated by a tree. The experiment was inspired by a MIT study from 2008 that discovered plants’ ability to generate tiny amounts of voltage when one sensor is attached to a plant and the other to the soil. The MIT study, however, never experimented with trees, and no one is entirely sure how trees produce power in the first place.
By hooking up nails to a bigleaf maple tree and connecting a voltmeter and a boost converter, the researchers were able to generate a steady voltage of up to a few hundred millivolts. UW researchers built their electricity-harnessing device out of a boost converter that stores as little as 20 millivolts of power from trees and releases up to 1.1 volts. The custom converter is capable of storing smaller amounts of power than any other boost converter in existence.
As you might expect, trees don’t produce nearly enough energy to power most electronic devices–there’s a reason we aren’t already hooking up our iPods to the nearest tree–but they do generate enough power for attached sensors to wirelessly keep track of environmental conditions or forest fires. And at a time when forest fires are becoming more and more severe, this technology could be a crucial part of figuring out where and how infernos begin.