Stephanie Butzer | High Point Times
HIGH POINT — Imagine if talking, standing in a warm area or moving your body could charge a cell phone.
David Carroll, the director of the Center of Nanotechnology and Molecular Materials at Wake Forest University, already has seen it.
Carroll was a guest speaker at the High Point Rotary Club meeting Thursday.
As the leader of the Carroll Research Group, Carroll and his colleagues founded PowerFelt, a fabric that generates power from body heat. Named as one of the 32 inventions that will change tomorrow’s world by The New York Times, PowerFelt stems from humans’ tendency to be mobile and free while staying connected.
“What I really want is a lifestyle in which the gadgets themselves can follow me, but don’t define me,” Carroll said. “I mean the gadgets don’t need to be next to a wall (and outlet) someplace.”
Humans in a technological society always will need a source of power, and the source cannot be a plug, he said. Instead, he chose to use the power of the human body, which gives off about 130 watts of heat energy per hour.
“The problem has always been that we could not embed the technology into the garment and make it so that it could be worn, washed and that people didn’t throw it away because it broke,” he said. “That’s changing with PowerFelt.”
In the lab, Carroll and his associates discovered that PowerFelt can produce power from heat, physical motion and vibrations, such as sound waves. Anything from talking with a peer to mountain biking to putting PowerFelt by a window on a hot day can create energy. Even tapping the fabric causes a spike in its energy output.
“This material generates power with pretty much anything you do to it,” Carroll said.
The amount of power available from PowerFelt depends on the temperature of the air and the person, as well as how fast they’re moving. Carroll said this is one major difference between PowerFelt and typical thermoelectric generators.
“Most of the time, thermoelectric generators, or generators of power of any kind, are considered devices,” he said. “A device — what does that evoke in your thoughts? To me, it’s always something that breaks. I have teenage kids.”
PowerFelt, on the other hand, is a fabric, which tends to be tougher than devices, he said. He wants the inherent property of the material to be the generating power. If somebody wears a shirt made of PowerFelt and goes for an easy hike, they can produce about .5 watts per meter squared, enough to give a dead phone a 50 percent charge.
The technology may sound expensive, but Carroll said it is simple to manufacture, which means it could be sold for a low price. Since electricity from outlets costs about 15 cents a kilowatt-hour, he said people could start saving in electricity what they paid for in clothing.
“All I have to do is wear a jacket made of this thing for about a year and a half to two years, and the jacket is free because I’ve generated enough power to have paid for the jacket by not plugging it into the wall,” he said. “The return on investment on this is interesting — just wear your clothing, which is something most of us tend to do.”
Today, the Carroll Research Group is working on technology for PowerFelt to communicate with cellphones, which in turn, can give information to the person wearing the fabric.
Carroll said this information could produce endless possibilities. For example, pants of PowerFelt could send a warning to somebody’s phone if they’re going to fall based on bones in the knee creating friction. It could alert somebody if they have bad posture. The fabric also could be made into a blanket, and if thrown over an injured person, it could detect hot spots like internal bleeding, an injured organ and even tumors.
At the end of the presentation, Carroll clicked to a slide showing a screenshot from the movie “The Matrix.” The scene shows the Morpheus character holding up a battery and telling another character he could change humans into one. Carroll said he never understood this part of the movie because batteries don’t last forever or need to be charged regularly.
“The human body isn’t a battery,” he said. “It’s a generator.”
Sbutzer@hpe.com — 888-3617