Vancouver teenager Ann Makosinski recently won prizes at a series of science fairs with the invention she’s calling a “hollow flashlight.” Here’s the video that’s been brightening up the Internet, apparently for a few months now, but I’ve just discovered it:
It’s an impressive invention for anyone; it’s particularly impressive, not to seem patronizing, coming from a 15-year-old. It’s one of those inventions that seems obvious in hindsight. The materials used in the flashlight are all off-the-shelf technology; you’d think we’d already have flashlights powered by our own body heat. Peltier thermoelectric tiles convert body heat from the hand of the person using the flashlight into electricity which powers an LED light bulb.
But maybe the technology hasn’t been on that shelf very long? I know LEDs haven’t been cheap enough or have required little enough power for an application like this until recently; I assume the same is true for Peltier materials, although I’d never heard of them before learning about this story. Apply heat and they give you electricity, but they work the other way too: apply electricity and they give you heat or cooling.
Makosinski got the idea for her flashlight when she visited a friend in the Philippines who couldn’t do homework at night because she had no electricity in her home. Makosinski now foresees many possibilities for technology extrapolated from her concept.
All her flashlight needs to provide usable light is a temperature difference of 5 degrees Celsius between the heat source (the person holding it) and the LED. She imagines desk chair seats in schools made out of Peltier tiles, allowing third world students to power their own classrooms.
Waste heat is everywhere we think to look for it, and much of it comes from our own bodies. Fans of the movie The Matrix may find that creepy, but it shouldn’t, so long as we’re using it for our own purposes and not those of an evil computer network. If school desk seats can incorporate this technology, I’d imagine so could watchbands, insoles, and underwear. Car seats, too, and couches, beds, and chairs at home: any objects our bodies interact with for extended periods could potentially become conduits for electric power. Even if the energy generated isn’t much, this girl has demonstrated that it can be enough for useful purposes.
Maybe the post-fossil-fuels home and workplace of the future will be served by a patchwork of fuel sources, with some power coming from things like this, some from solar, wind, and other alternative fuels we’ve already heard much about, some from (just spitballing here) the weight of our footsteps across the floor, exothermic reactions in decaying garbage, and other technologies we haven’t even guessed at yet.
It’s exciting to think about.