Hot property: devices can be powered by material sensitive to body heat

A bio-friendly material can generate electricity using a thermoelectric process involving heat and cold air.

Dan Hixson/University of Utah College of EngineeringUniversity of Utah materials science and engineering professor Ashutosh Tiwari and his team have an inexpensive and bio-friendly material that can generate electricity through a thermoelectric process involving heat and cold air. The material (the black blocks between the two plates pictured) could be used with cooking pots to charge phones or jewelry to power health sensors.

Items such as personal jewellery and cooking utensils may soon be able to use human body heat to generate enough electricity to power gadgets and mobile phones.

A combination of calcium, cobalt and terbium was found able to create an efficient bio-friendly material capable of generating electricity through a thermoelectric process using heat and cold air.

A thermoelectric effect is where the temperature difference in a material generates an electrical voltage.

Ashutosh TiwariThe heat from a hot stove, coupled with the cooler water or food in a cooking pot, could generate enough electricity to charge a cellphone.

When one end of the material is hot and the other end is cold, charge carriers from the hot end move through the material to the cold end, generating an electrical voltage. Scientists have been searching for a non-toxic material that can make the process more efficient and produce more electricity than has been achieved so far.

An advantage of this material is that it is inexpensive to produce as well as bio-friendly, eco-friendly and efficient.

The research team that worked on the project, and recently published a paper on its findings, was led by University of Utah materials science and engineering professor Ashutosh Tiwari who confirmed there are no toxic chemicals involved.

He said: “It’s very efficient and can be used for a lot of day-to-day applications.”

Tiwari is convinced that the applications for the material are extensive. For example, jewellery could use body heat to power implantable medical devices such as blood-glucose monitors or heart monitors.

It could also be used to charge mobile devices in cars where it could draw from the heat of the engine. The heat in the cabin of an airliner when set against external cold air could be used to generate extra power. Furthermore, the escaped heat from power plants might also be used to generate additional electricity using the material.