Published on February 24th, 2012 | by Nicholas Brown0
Imagine Electricity-Generating Clothes,… but Without Solar Panels on Them
February 24th, 2012 by Nicholas Brown
Researchers from Wake Forest’s Center for Nanotechnology and Molecular Materials announced this week that they have manufactured a material that can generate electricity using your body heat.
The material, Power Felt, uses carbon nanotubes (it is, after all, a nanotechnology research institution), which have, in the recent past, been used to demonstrate some of the most amazing technologies ever to exist. One such technology is graphene transistors, which are the fastest in the world, from IBM. But, back to Power Felt….
The Technology: Power Felt
Power Felt is a thermoelectric material, meaning that it uses a temperature difference between both of its sides to generate electricity. Thermoelectric materials also generate heat when supplied with electricity.
Thermoelectric devices are usually rigid, brittle (although flexible versions have been invented recently), and are composed of bismuth telluride. But Power Felt avoids that drawback.
“Comprised of tiny carbon nanotubes locked up in flexible plastic fibers and made to feel like fabric, Power Felt uses temperature differences – room temperature versus body temperature, for instance – to create a charge,” Katie Neal of Wake Forest University writes.
All generators that produce electricity using heat are very inefficient. Despite this poor efficiency, however, heat is abundant almost everywhere and is generated by all appliances (even the human body), making thermoelectric generators, which contain no moving parts and can last hundreds of thousands of hours, well worth developing. Or, at the least, they deserve further research and development.
If an energy source is abundant and can cost as little as nothing, such as the waste heat produced by engines, solar energy, or wind energy, then even a low efficiency may be practical.
“We waste a lot of energy in the form of heat. For example, recapturing a car’s energy waste could help improve fuel mileage and power the radio, air conditioning or navigation system,” Corey Hewitt, a PhD student working on the technology, says. “Generally thermoelectrics are an underdeveloped technology for harvesting energy, yet there is so much opportunity.”
How Power Felt Can be Used
“Since these fabrics have the potential to be cheaper, lighter, and more easily processed than the commonly used thermoelectric bismuth telluride, the overall performance of the fabric shows promise as a realistic alternative in a number of applications such as portable lightweight electronics,” the researchers noted in the research paper.
Potential applications of the Power Felt technology include charging mp3 players, cell phones, and powering medical monitoring equipment. It would be great if it could power electronic implants too, but that depends on how the body’s immune system reacts to it.
“Imagine it in an emergency kit, wrapped around a flashlight, powering a weather radio, charging a prepaid cell phone,” says David Carroll, director of the Center for Nanotechnology and Molecular Materials and head of the team leading this research.
Clearly, there are many potential applications.
Wake Forest may move to have Power Felt developed commercially and is currently in talks with investors about this.
The research has just been published in Nano Letters, a leading journal in nanotechnology, if you’d like to learn more.