Grab the torch! And just by holding it you get 20 minutes of LED light with no batteries.

Aged just 15, young scientist Ann Makosinski has invented a prize-winning, hollow, battery-less flashlight powered simply by the warmth of her hand, after learning a friend in the Philippines was having trouble in school because she had no light to study at night.

Not that there’s much call for flashlights now that mobile phones come equipped with them, still, Makosinski , from Victoria, Canada, invented her torch in a sincere attempt to change the world.

For her efforts, she was a winner in the 2013 Google Science Fair.

The most important part of her invention is not the flashlight, which, as already mentioned, is virtually obsolete. It is that a 15-year-old cares so much about the environment and the world that, hopefully, in the future she and others will come up with more smart inventions using human energy.

In a You Tube video, Makosinski tells how she made the flashlight, saying she became interested in the area of “harvesting surplus energy” after learning “humans are a great source of untapped thermal energy”.

To produce enough power to turn on LED lights in the torch, Makosinski says she used four Peltier tiles. If one side of the tile is heated by a human hand and the other exposed to cool air, electricity is produced.

Her design was based on the Seebeck effect, discovered by German physicist Thomas Seebeck in 1821, which states that electric current is produced when two dissimilar metals are joined, and one side of their junction is cooled and the other is heated.

After Makosinski worked out the figures, she proved that the energy from a human hand could produce enough electricity via the Peltier tiles to power an LED in a torch. And after several prototypes, a few failures and lots of exasperation, she produced two working prototype flashlights — one aluminium and one PVC pipe.

Rather than being just another human using up the world’s resources, Makosinski did what she could to ease the environmental impact of the tonnes of batteries used and thrown away by people around the world. In a TED Talk she asked what the politicians were doing personally to reduce carbon emissions.

“Recently, after talking to one of our local green party politicians,” says Makosinski, “I saw her drive away in a hybrid, my dream car, the one that is actually good for the environment, or so we are led to believe.

“Come, on! Hybrid still has wheels, and a frame, and a gasoline engine and an electric motor and a gigantic nickel hydrate battery,” she says.

“And what happens to that battery when it has to be replaced? A recent analysis from the National Research Council in Canada has proven that ‘the environmental damage stemming from hybrids and electric vehicles will be greater than that of traditional gasoline-driven cars until at least 2030’.”

“So is the person driving a hybrid really saving the world? Or is it just sales talk?”

She asked what a 15-year-old could do about the problem. “Well, maybe not about the car our parents drive in, not on product labelling, but yes, I think we can make a difference.”

She says her story may not be the best example. “My first toy was actually a box of transistors … in grade six I started participating in the local science fair. Most of my projects were energy-related and included experimenting with Peltier tiles, piezoelectric discs and solar cells. This year I made a flashlight that worked solely from the heat of the human hand.”

The young scientist and her invention have received international attention since then. She was a guest on The Tonight Show with Jimmy Fallon, showing off the body heat-powered flashlight that won her a top prize. As a then Grade 11 student at St Michaels University School in Victoria she was named one of Time magazine’s 30 under 30 in 2013 and has given two TED Talks.

During a TED Talk, she said someone at school had called her a dilettante, so she looked up the word and now calls herself an ‘envirottante’ , that’s a cross between an environmentalist and a dilettante. She went on to question the philosophy and commitment of being ‘green’. When her experiment worked she said she realised: “We have the power to give something to the world, that we can actually give something to the environment, to actually be a resource, rather than being the one who takes away the resources.”

The final step in her experiment, after working out how much energy the human body emits, and how much she needed to power a torch, was the physical aspect of her design.

“Because I only needed to heat one side of the Peltier tiles the heart of my design was the hollow aluminium tube. The air flowed freely through the tube and also cooled the other side of the tiles. My results proved my hypothesis, and I was able to produce around five mW of power and five foot candles of brightness. I achieved my objective of creating a flashlight that runs solely on the heat of the human hand.”

The parts that went into the torch cost a mere $26.

Makosinski says she was inspired by Nikola Tesla, Marie Curie, and Pandit Ravi Shankar.