Canadian schoolgirl creates Hollow Flashlight powered by body heatSubmitted by Bob-45 on Mon, 07/01/2013 - 16:42
By Dave LeClair
June 30, 2013
At the tender age of 15, Canadian high school student Ann Makosinski has designed and built a flashlight powered by body heat. Her Hollow Flashlight secured her a finalist slot in the 15-16 age group of the Google Science Fair ahead of thousands of entries from more than 100 countries. My science project in tenth grade was a volcano that only worked about half the time, so I think she has me beat.
The LED flashlight relies on the thermoelectric effect, with tiles that generate electricity from the differences in temperature to generate electricity. The tiles are fixed to the outside of a hollow tube so that when held, one side of the tile is heated by the warmth of the hand, while air flowing through the hollow tube helps keep the other side cool. The electricity generated by the temperature differential between either side of the tile powers the LED light.
Makosinski built two different flashlights. The first was made using a tube of aluminum, which is a good heat sink material thanks to its high thermal conductivity, while the second was built using a PVC tube.