Money Doesn't Grow On Trees, But Perhaps Electricity Does

Trees produce electricity. How electrifying.

In an experiment that will seem familiar to students of the old potato project, University of Washington researchers stuck one electrode into a bigleaf maple, and another in the ground, and saw that the tree generated a tiny stream of electricity - a few hundred millivots. That's not enough electricity to do much, except to run a circuit and get published in the scientific journal Institute of Electrical and Electronics Engineers' Transactions on Nanotechnology.

(As of that potato, this experiment is different, the authors said: "The tree-power phenomenon is different from the popular potato or lemon experiment, in which two different metals react with the food to create an electric potential difference that causes a current to flow." The tree experiment uses the same metal for both electrodes.)

A few hundred millivolts of electricity isn't enough to do much. Or is it? The scientists built a custom boost converter using nanotechnology that stores input voltages of as little as 20 millivots (20 thousandths of a volt) and produces 1.1 volts -- enough to run low-power sensors that might monitor environmental conditions, help detect forest fires or gauge the health of trees.

And in the future, who knows? Maybe we will be plugging in our iPods on long hikes with a little tree power.