A Canadian schoolgirl has invented a flashlight powered using just the heat from a human hand. Fifteen-year old Ann Makosinski, a Grade 10 student at St. Michaels University School in Victoria, used Peltier tiles and an aluminum tube to power three LED bulbs to earn herself a place at the Google Science Fair.
Peltier tiles take advantage of the thermoelectric effect to create voltage. After performing some basic calculations, Makosinski found that although the tiles produced enough energy, the voltage was insufficient, but a power converter integrated circuit solved the problem. The final design involved an aluminum pipe placed inside a larger PVC pipe and LEDs centered in the middle of the tube.