At an age when most teenagers are focused on school and social activities, a 14-year-old Canadian girl has captured international attention with a brilliant invention: a flashlight that operates solely on the heat from a human hand, without the need for any batteries.
Ann Makosinski, from Victoria, British Columbia, created what she calls the “Hollow Flashlight” for the 2013 Google Science Fair. The project was inspired by a friend in the Philippines who struggled to study at night due to a lack of electricity. This simple yet profound problem led Ann to explore a solution using the science of thermoelectricity.
The flashlight is ingeniously designed around a principle known as the Peltier effect. It uses small, affordable thermoelectric generator (TEG) tiles, which produce an electric current when one side is heated and the other is cooled. Ann’s design ingeniously leverages this effect. The flashlight has a hollow aluminum tube inside a PVC pipe. When held, the user’s hand heats one side of the tiles, while the cool ambient air flowing through the hollow core cools the other side. This temperature difference is enough to generate power for an LED bulb, providing a steady beam of light for up to 20 minutes, even with a small temperature differential.
Her project won the top prize in her age category at the Google Science Fair, and she was the sole Canadian representative at the finals. The invention is not only a marvel of engineering but also a beacon of sustainable innovation. The device, which cost less than $30 to build, could be a game-changer for millions of people worldwide who lack access to reliable electricity.
Ann’s achievement has since made her a celebrated young inventor, with appearances on television shows and speaking engagements. Her story is a powerful reminder that some of the most impactful solutions come from the simplest of ideas and are often driven by a desire to help others.
