Chin strap generates electricity from chewing

System that uses piezoelectric material could be used for military applications

Engineers in Canada have developed a chin strap that harnesses energy from chewing, which could replace batteries in hearing aids, earpieces and other small gadgets.

Dr Aidin Delnavaz and Dr Jeremie Voix, mechanical engineers at the École de Technologie Supérieure, have created a system that uses piezoelectric material which becomes electrically charged when stretched.

Their prototype chin strap can generate 18 microwatts from 60 seconds of chewing, but the technology would need to be made 20 times more efficient in order to generate useful amounts of electricity. However, Delnavaz and Voix believe this can be achieved by adding layers of the material.

“For example, 20 PFC (piezelectric fibre composite) layers, with a total thickness of 6mm, would be able to power a 200 microwatt intelligent hearing protector,” Dr Delnavaz told the BBC.

The engineers said they had been approached by companies interested in charging solutions for bluetooth headsets. The system would also be suitable for military applications.