Human-powered wearables

Scientist have found a way to harvest of energy you spend when u exercise and turn it into electricity. No-one will be plugging themselves into the grid any time soon, but researchers at the the University of Colorado, Boulder, believe their technology could power a heart-rate monitor or fitness tracker.

The team was able to fit thermoelectric generators into stretchable film bands that can be worn around the wrist. They cost less than $10 to make, and because they’re made from a liquid metal and polymer, they are both self-healing and easy to recycle.