Power Felt generates electricity from body heat
By Ben Coxworth
February 22, 2012
Some day, your jacket may be able to power your iPod ... and no, I'm not talking about piezoelectric fabrics (which generate electricity from movement-caused pressure), nor am I talking about photovoltaic materials, although both of those could probably do the job. Instead, your jacket might be made out of a new thermoelectric material called Power Felt, that converts temperature differences into electrical voltage - in the case of the jacket, the difference between its wind-cooled exterior and its body-warmed lining might be all that was needed.
Power Felt was created by a team of researchers at North Carolina's Wake Forest University, led by graduate student Corey Hewitt. The material is made up of carbon nanotubes contained within flexible plastic fibers, and reportedly feels like regular felt. Should you choose to feel it, the temperature of your bare fingertip will be enough to create a measurable current.
Although thermoelectric energy-harvesting materials such as bismuth telluride do already exist, the researchers believe that Power Felt could be much more cost-effective - they state that integrating it into a mobile phone cover, for instance, might boost the price of that cover by only one dollar.
Along with phone covers, the material could also find use in things such as flashlight housings, pipe insulation, sports equipment, or wound wrappings. It is even suggested that the felt might be used for automobile seat upholstery, where it could utilize the driver's butt warmth to boost the car's battery or help run its electronics. Essentially, it could be used in just about any setting where it would be exposed to a wide temperature gradient.
Hewitt is presently looking into making Power Felt thinner, while boosting the number of nanotube layers, and thus its power output. The university is in the process of meeting with investors, in order to fund the commercial development of the material.
A paper on the research was recently published in the journal Nano Letters.
Source: Wake Forest University