Ann Makosinski won in the 15-16 age category, beating out thousands of other budding young scientists from around the world to be one of four winners.
The "Hollow Flashlight" runs off the heat from the palm of the hand, using special tiles that generate electricity from the heat flowing between the palm on one side and the ambient air on the other.
"I chose to investigate the aspect of human energy when I found out that we are like walking 100-watt light bulbs. The goal of my project became a flashlight powered solely from the heat of the human hand," Makosinski told the science fair judges.
Inspired by her visits to small villages in the Philippines, where she said many kids don't have electricity for lights that would let them study at home.
Makosinski said in a video posted on the science fair website that she also wanted to reduce the number of batteries being discarded into the environment.
For her project, she used devices called Peltier tiles, which produce electricity when one side is heated and the other cooled.
"I made two flashlights that do not use any batteries, toxic chemicals, or kinetic energy. They do not create any noise or vibrations and will always work," she said.
"The flashlight’s only limitation is its need for at least a 5 Celsius temperature difference to provide usable light."
The Grade 10 student at St. Michael's University in Victoria said she would like to explore more ways to use the technology to reduce battery use, including possibly in medical devices.
She credited her family for encouraging her interest in science, telling the judges that her first toy was a box of transistors.
Makosinski also thanked St. Michael's science club teacher Kate Paine, who guides the school's science fair team and who was thrilled for her student on Tuesday.
"I'm just so incredibly excited and proud of her," Paine said Tuesday.
"It's kind of humbling. It's incredible that someone that age can come up with something so amazing."
She said Makosinski has competed in many science fairs, and has become "a bit of a pro at it."
She has a keen interest in electronics, and has the encouragement of her father, who works in the engineering department of the University of Victoria, Paine said.
"I think her love of just building things and her natural curiosity, combined with this love she's found for flashlights and alternative forms of energy have just led her to this point," Paine said.
Makosinski received the good news and a $25,000 scholarship with three other winners at a gala ceremony in California on Monday night.
"To be honest, I am not sure exactly what I want to study in the future just yet," she told the judging panel. "I'm thinking it will probably be the Sciences."
Other winners included grand prize winner Eric Chen, a 17-year-old from the United States who worked on a new anti-flu medicine, 16-year-old Elif Bilgin of Turkey who created bioplastics from banana peels, and 14-year-old Viney Kumar of Australia and his new signalling system for emergency vehicles.
Note to readers: This is a corrected story. A previous version said there were five winners.
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