Power Felt converts heat into electrical current

A promising new thermoelectric device capable of converting body heat into electrical current has been developed in the US.

Power Felt is comprised of tiny carbon nanotubes locked up in flexible plastic fibers and made to feel like fabric. It uses temperature differences – room temperature versus body temperature, for instance – to create a charge. "We waste a lot of energy in the form of heat," said Wake Forest University graduate Corey Hewitt. "For example, recapturing a car's energy waste could help improve fuel mileage and power the radio, air conditioning or navigation system. Generally thermoelectrics are an underdeveloped technology for harvesting energy, yet there is so much opportunity." Potential uses for Power Felt include lining automobile seats to boost battery power and service electrical needs, insulating pipes or collecting heat under roof tiles to lower gas or electric bills, lining clothing or sports equipment to monitor performance, or wrapping IV or wound sites to better track patients' medical needs. "Imagine it in an emergency kit, wrapped around a flashlight, powering a weather radio, charging a prepaid cell phone," commented David Carroll, director of the university's Center for Nanotechnology and Molecular Materials. "Literally, just by sitting on your phone, Power Felt could provide relief during power outages or accidents." While cost has been the main prevention to thermoelectrics being more widely used, the researchers claim Power Felt would only cost $1 to add to a mobile phone cover. They are now planning to add more nanotube layers to the device to boost the power output. Hewitt concluded: "Although there's more work to do before Power Felt is ready for market, I imagine being able to make a jacket with a completely thermoelectric inside liner that gathers warmth from body heat, while the exterior remains cold from the outside temperature. "If the Power Felt is efficient enough, you could potentially power an iPod, which would be great for distance runners. It's pretty cool to think about, and it's definitely within reach."