Happy days for prolific users of mobiles with news that researchers at a US university have found a way to power handheld devices just by walking or running.
Engineering students at the University of Wisconsin-Madison have harnessed the kinetic energy from movement to feed straight into the battery cells of handheld devices, meaning a user can simply walk around a location safe in the knowledge that they will not have to find a power supply when the charge expires.
The project takes the idea of using solar energy one step (literally) further, without the worry of a lack of direct sunlight or general ambient light.
Those behind the project are calling the technology "reverse electrowetting", whereby mechanical energy (such as movement) is converted to electrical energy using a device consisting of thousands of liquid micro-droplets interacting with as "nano-structured substrate".
In short: the technology would sit in the shoe of the user and switch the walking or running motion to electrical power.
Up to 20 watts of electricity could be used to power mobile phones, tablets and other handheld devices, the researchers say.
"Alternatively, the energy harvester can be integrated with a Wi-Fi hot spot that acts as a "middleman" between mobile devices and a wireless network.
"This allows users to seamlessly utilize the energy generated by the harvester without having to physically connect their mobile devices to the footwear. Such a configuration dramatically reduces power consumption of wireless mobile devices and allows them to operate for much longer time without battery recharge."
Two professors leading the project, Tom Krupenkin and J. Ashley Taylor, have registered a company - InStep NanoPower - to potentially develop the technology on a commercial basis.