Converting Body Movements Into Electricity

From the New York Times...

"It may not seem like it, but even the laziest of couch potatoes is a human dynamo. The act of breathing — of moving the ribs to draw air into the lungs and expel it — can generate about a watt of power. And if the potato actually gets up off the couch and walks briskly across the room, each heel strike can produce even more power, about 70 watts’ worth.

That energy could be put to work, charging a cellphone, say, or a medical sensor inside the body. The problem is how to harvest it."

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