Book 26, Question 81
How did a teenager invent a flashlight that needs no batteries?
Ann Makosinski, from British Columbia, was fifteen when she built the Hollow Flashlight.
It uses small thermoelectric tiles that turn the difference between the warmth of your hand and cool air into a tiny bit of electricity. That electricity powers an LED. She won an award at the Google Science Fair in 2013. Her idea shows how heat can be turned into power.