ECG system harvests human heat

Belgian researchers have developed a way to convert body heat into a powerful energy source.

A team from IMEC and the Holst Centre unveiled wearable energy-harvesting devices that can provide tens of microwatts of energy per square centimetre, for modules with 3 x 4cm2 dimensions.

Current wearable thermoelectric-energy generators have so far proven their capability to power small personal devices, such as watches, without needing an external power source. The thermal harvester developed by the Holst Centre and IMEC can provide enough power for an autonomous wearable electrocardiography (ECG) system and a radio that transmits the ECG signal in real time to a base station.

The thermal harvester is made of bismuth telluride, a thermoelectric material that converts human body heat into electric current. Once this device is placed close to the body, it generates electricity that is further accumulated in an energy-storage system.