Ultimately, it should prove to be more practical than solar energy or wind power, and certainly more affordable than fuel cells, he added.
Basically, the existing system includes a metal rod embedded in the tree, a grounding rod driven into the ground, and the connecting circuitry, which filters and boosts the power output sufficient to charge a battery. In its current experimental configuration, the demonstration system produces 2.1 volts, enough to continuously maintain a full charge in a nickel cadmium battery attached to an LED light.
It is enough power to charge batteries for any type of vehicle, including hybrids and electric cars, or to use with an AC converter to produce household power, he added. The LED industry is a prime example of a potential user of this power source.
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