If you generate a lot of excess body heat — and there's no shame in it — then it would make sense to put it to good use. A new wearable fabric called Power Felt could be the answer; it can generate electrical current from temperature differences.
Developed by researchers at the Center for Nanotechnology and Molecular Materials at Wake Forest University, the new material is made up of carbon nanotubes locked up in flexible plastic fibres. Those fibres are woven together into a material that feels like felt, but reacts to temperature gradients to produce an electrical current. The research appears in Nano Letters.
The researchers suggest that it could be used around insulating pipes, under roof tiles, or even under your arse in car seats to make the most of waste heat. Of course, you could always get yourself a pair of Power Felt running shorts to keep your phone topped up on the go, too. I bet you look good in felt.
While the fabric is very much real, there is a small drawback. Currently, 72 stacked swatches of the — admittedly very thin — fabric yield about 140 nanowatts of power. That is not a lot of power. To put that in perspective, it's of the order of a millionth of the power your iPhone uses when it's idle. So, you'll need a lot of layers or some very large clothes to make the most of it right now. The researchers are confident they can improve the material's efficiency, though. Corey Hewitt, one of the researchers, says:
"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 definitely within reach."