CreativeWire

Next time your phone runs out of battery in the middle of nowhere while you are desperately trying to send that tweet that will change the world, the solution might be as easy as wearing a solar thermoelectric device that generates energy simply by being attached to clothes, walls or even windows!

A recent study led by professor Kyoung Jin Choi in the School of Materials Science and Engineering at UNIST, has developed a new energy harvesting technique that can generate electricity by exploiting the temperature difference between the hot and cold sides of the device. Conventional methods that convert body heat to energy are often inefficient due to the fact that the standard temperature difference they can create typically ranges from 1.5 to 4.1 °C. However, the device developed by professor Kyoung Jin Choi and his team managed to bypass this limitation by raising the temperature difference up to 20.9 °C, thanks to the introduction of a solar absorber that harvests solar energy.

Power harvesting or energy scavenging is a scientific field that focuses mainly on extracting energy from external or ambient sources such as solar power, kinetic energy and thermal energy. This ambient energy is then stored and used to power wearable electronics such as smart watches. The term "scavenging" simply refers to the fact that ambient energy is mostly a wasted power source that could otherwise be exploited and used to power our electronic devices.

The device built by the team is a thermoelectric generator that relies on the temperature difference created by both body heat and sunlight. A thermoelectric generator (TEG) is a device that converts wasted energy, mostly heat energy, to electrical power.

The research team hope that their study, which was published in the August issue of the prestigious journal Nano Energy, will open up new prospects for the commercialization of wearable generators.

Photo courtesy of: UNIST