Each of us, just sitting in our chairs, is a little heat energy factory. So why not harness that body heat to power our phones and flashlights? Researchers have invented a thin, flexible “power felt” that can be worn as clothes, converting heat into an electric current. Dead batteries are so out in the future.
The thermoelectric fabric is made by stacking layers of plastic insulation with carbon nanotubes, one-atom-thick cylinders of carbon that are showing up everywhere from x-rays to fuel cells. The current version only makes about 140 nanowatts of power, so it’ll need some improvement before it becomes practical.