Has anyone built one of these Flashlights

[LI0NSFAN]

I was looking around the net and came across a cool idea for a survival light. It does not put out a ton of light but has a long "battery" life.  I was wondering if anyone has made one or seen one work in person.

 

 

http://www.youtube.com/watch?v=fRdeFcIK8QM

[walton6467]

Pretty cool!

[TripleDigitRide]

While she's obviously a very smart kid, the output doesn't appear very impressive or usable, even for it's design.

Edited July 4, 2013 by TripleDigitRide

[RichardR]

I'm on 3G so I can't watch the video, but I'm guessing it works on a thermocouple principle?

[TripleDigitRide]

I'm on 3G so I can't watch the video, but I'm guessing it works on a thermocouple principle?

Yes, which means it would worked better in cooler climates, and be pretty well useless at temperatures closer that of the human body.

[LI0NSFAN]

While she's obviously a very smart kid, the output doesn't appear very impressive or usable, even for it's design.

I am guessing it is only a matter of time before a useable version is made. When I saw the video I was under the impression this was a type of flashlight that has been around and she just made one for the science fair. I now know that she developed a new type  of flashlight and it has only been around for a couple of months. She is a very impressive young lady, at 15 I was not trying to build a new version of anything.

[RichardR]

Thermocouples are extremely inefficient, it's doubtful technology will be able to produce one small & powerful enough for the heat of someones hand to power a device that consumes more energy than say a very low-drain device like say wrist watch or calculator or something.

A couple nails poked into a potato will light an LED up a little bit, the trick is getting useful amounts of energy out of it.

At the moment the best bet is the hand-crank/generator lights, best output vs energy expended, aside from traditional battery power for emergency use that is.