A hollow flashlight powered by the heat from a user's hand, designed by a 15-year-old girl from Victoria, has been picked for the finals of the Google Science Fair.

Ann Makosinski, a Grade 10 student at St. Michaels University School in Victoria, is one of 15 students from around the world who beat out thousands of entries from more than 100 countries to earn their spot as finalists.

They will visit the Google campus in Mountain View, Calif., in September for the prize ceremony, Google announced Thursday. Winners will be chosen in three age categories, and one will receive the grand prize, which includes a $50,000 scholarship from Google and a trip to the Galapagos Islands.

http://www.cbc.ca/news/technology/story/...makosinski.html

Brilliant.

Way to go! Very illuminating article....

Amazing, such an inspiration

Flashlight? No, that should be properly called a "fleshlight."

I just googled the term to check for copyright issues. Please don't repeat my mistake.

I wonder how a headlamp with a peltier pile would work? Due to male pattern baldness, my forehead extends over my scalp to a point even with the back of my ears. Seems I should be able to generate lots of power!

I am very doubtful about this.
Warmth or heat alone can not generate electricity, what is needed is a temperature difference.
If one side of a peltier chip is warm and the other side is cold then electricity can be produced.

In the case of a flashlight the heat from the users hand is unlikely to work well.
In hot weather with the suroundings at near blood heat there wont be enough temperature difference.
In cold conditions the user would probably be wearing gloves and/or have cold hands at far below blood heat.

LOL!! I can only imagine. haha!

It´s more a proof of concept than a useful application. The interesting thing about it is the driver circuit. Before you use the harvested energy, you need to know how much you are going to harvest. A LED is just right for that.

I am skeptical that it will ever be practical but as a toy it is interesting.

I am not sure what the reference to transformers in the article is about. The backwards thermocouples produce DC voltages that can be readily increased with voltage doubling circuits that are mostly cheap capacitors.

This is proof of concept by a girl who spent $26 dollars on materials. I'm sure there are practical applications if we think hard enough and if we threw some money at it. The circuit is probably an invention. I hope she has something on file at the USPTO.

By the way, I would like to know who saw the video when they post. The girl explains a typical journey of an inventor. She also mentions the weaknesses that some have repeated here. Her story is inspiring. It's worth a watch. I hope to raise my daughter to have her type of confidence.

It just sounds like a solid state boost circuit to me, been in LED flashlights for the past 5+ years, and you can buy one for a few bucks shipped.

I can't imagine no flashlight company ever tried this concept, probably did and concluded it's not viable.

Yes, that's what she did. The linked article says she had a hollow tube, with ambient air on the inside to provide the coldness. She says it worked for at least 20 minutes, so presumably she had enough air-flow through the tube to keep it cool enough.

Yes, she says it was brighter with an ambient temperature of 5C than of 10C, but even at 20C there was enough power to produce light. I see this partly as a testament to the efficiency of modern LEDs.

Of course, you need to manage your expectations. It's not going to be as bright as an AAA-powered key-chain light. However, the darker it is, the less light you need, because your eyes adjust. 1-3 lumens can be enough to find your way indoors.

I think this technology should continue working indefinitely. It's not like a wind-up torch where there are a lot of mechanical parts that can break. Those often use a battery to store the power anyway, and that battery will have a limited lifetime.