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Science Forum

  1. Standard member sonhouse
    Fast and Curious
    01 Jul '13 13:02
    http://phys.org/news/2013-07-student-flashlight-body-batteries.html#firstCmt

    This is one kid with a future! Brilliant idea.
  2. 01 Jul '13 17:50 / 3 edits
    Yes, that is a smart kid. I am surprised it can make useful amounts of light from just a few degrees temperature difference.
    The brightness of that light currently does seem pretty feeble though but if the energy efficiency can be greatly improved so to make that light a lot brighter then that's definitely going to be a winner.
    No batteries would mean it would be very light-weight and it should be very reliable.
  3. Standard member sonhouse
    Fast and Curious
    02 Jul '13 11:35
    Originally posted by humy
    Yes, that is a smart kid. I am surprised it can make useful amounts of light from just a few degrees temperature difference.
    The brightness of that light currently does seem pretty feeble though but if the energy efficiency can be greatly improved so to make that light a lot brighter then that's definitely going to be a winner.
    No batteries would mean it would be very light-weight and it should be very reliable.
    If peltier converters can get cheaper they could be put inside clothing and generate a lot more energy that way. I see one improvement in her design:

    Add a super capacitor to store energy so it takes say, one minute to light up but will have much brighter light for a short period of time.

    Have you seen the kind that have a sliding magnet and coil around it to generate power in a flashlight?

    I invented that, for a father son science fair but was to dumb to capitalize on the idea. I had taken a metal slinky and we held it open and I sprayed varnish on all the surfaces so it would have an insulating layer, then held it together and soldered wire on both ends, and used a magnetic compass with about 100 turns of very fine wire wrapped around it. The slinky was the large size, 3 inches in diameter, then used a small diameter plastic slinky with a magnet glued inside it where it could move back and forth, put all that in a plastic cylinder so you could see the action. We called it 'the generation and detection of electricity with 2 moving parts, one, the inner magnet and 2, the needle of the compass. It worked. Shaking the assembly caused the magnet to move inside the slinky coil which converted that to a current that moved the compass needle a little bit. It was visible movement and really caught the eye of the judges but some stupid volcano won