15-year-old Canadian girl invents flashlight powered only by body heat

15-year-old Canadian girl invents flashlight powered only by body heat and earns spot in Google Science Fair finals

This girl's science project really puts your baking soda volcano to shame A 15-year-old girl in Canada has invented a flashlight that only needs the warmth of the hand to turn on.  Ann Makosinski, a high school junior in Victoria, British Columbia, was trying to think of a way of harvesting untapped energy when she was inspired to make the flashlight.

She realized that the warmth generated by the human body was an overlooked energy source. 
Her project objective was to create a flashlight that ran solely off the heat of the hand. 
That objective was accomplished when she discovered Peltier tiles, which produce electricity when one side of the tile is heated and the other is cooled. 

Makosinski realized she could use these tiles to create energy for her flashlight if she left the device hollow. 
Holding the flashlight on the outside would cause the tiles to heat  up on one side while the ambient air would cool down the tile on the inside of the flashlight.  The power created by the tiles was enough to power an LED light, but it did not create enough voltage. 

To troubleshoot that issue she created a circuit that would allow for transformers, upping the voltage. 
It worked! The flashlight does have one issue: it works better in colder temperatures since the inside is better able to cool down comparative to the person's body heat.

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