As eardrum vibrations naturally create a usable voltage from brain signals, the prototype can build enough charge in a capacitor to drive a very low-power wireless transmitter that relays the electrochemical properties of the ear and potentially diagnoses balance or hearing problems.

ENGADGET: MIT ear-powered wireless sensor sustains its charge through sound

Substations and transformer boxes eventually reduce the power to the 110 volts that toast your muffin in the morning, but the electrical noise on a high-voltage line can destroy data signals immediately.

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