Personal charging.

• Position: TECHNOLOGY - Brief article

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It seems that even the Laziest of couch potatoes is a human power generator: Taking a breath and exhaling can produce about a watt of power, and walking briskly to the fridge can generate about 70 watts' worth. All that energy could be put to work--if there were a way to harness it. Now a team of scientists at Princeton University has come up with an approach that could start converting all that body motion into electricity: They printed piezoelectric crystals--which produce electric current when they're bent--onto...