Alternative to hearing aids batteries? Energy harvesting from the jaw


© Sylvie Thenard - Fotolia

Changing batteries is a costly part of hearing aids use that requires good dexterity. It also creates environmental waste. Researchers may have found a new source of powering hearing aids – jaw movement. Researchers at the École de Technologie Supérieure, Montréal, Canada, are investigating the possibility of harvesting energy from jaw movement to power hearing aids. Until recently, hearing aids were quite demanding in terms of energy. But substantial improvements now mean that these devices require less energy and have become good candidates for energy harvesting technologies.

The idea behind the system relies on the fact that opening the mouth contracts the face muscles and pulls the lower jaw down. The lower jaw is articulated to the head very close to the ear canal, so its displacement deforms the soft tissue in this area. Each alternating motion in the cycle generates energy and this occurs thousands of times over the course of the day when one eats or speaks. Initial capacity testing has shown that significant energy can be harvested in this way, enough to power hearing aids for several hours.

The research team has partnered with the industrial Sonomax Technologies Inc., a Quebec-based company specializing in hearing protection technologies, to integrate the energy harvesting module into custom-fitted earpieces. The energy harvesting module should be basically transparent to the user of the in-ear device, with no electrical connection extending outwards, no battery to periodically change, and no significant weight added to the device.

Source: Energy harvesting journal; École de Technologie Supérieure