Young scientist and her awesome human-hand-heat-powered flashlight

Alan sez, "Ann Makosinski, a Canadian girl scientist, describes her Google Science Fair submission: an LED flashlight that runs solely on the heat of the human hand. According to the GSF site she is one of 15 worldwide finalists at this point.

The Hollow (Thermoelectric) Flashlight - Google Science Fair (Thanks, Alan!)

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  1. Let's see: 5mW/cm^2 * 1.75 m^2 (avg skin area per human) * 7 billion = 613 GW. Wikipedia says that the world uses about 2.3 TW. We will need to start conserving energy if we wish to have a Matrix-style future where energy is harvested from our skin.

    In any case, this is a smart kid, but a windup device would be more effective. The best you are going to get thermoelectrically from a flashlight handle is ~50 mW, while you can easily get more than a watt from a dynamo that charges into a capacitor or a battery.

  2. Cory - why do you differentiate between "girl" and "boy" scientists?

  3. What part of quotation marks are you having trouble with?

  4. Yes, but to get a steady watt from a hand crank, you have to be cranking it the whole time. If your flashlight works acceptably on 50 mW, that's 1 minute cranking for ever 20 of use.

    I'll take 0 minutes cranking per infinity minutes of use, myself...

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