A pair of mechanical engineers from University of Wisconsin in Madison have designed a system to harvest some of the energy that is lost while we walk. Ashley Taylor and Tom Krupenkin, authors of “Reverse electrowetting as a new approach to high-power energy harvesting” published here on August 23, 2011; have founded InStep NanoPower in order to bring this concept to market.
“The mechanical energy produced by humans during walking, which is normally simply lost as heat, is captured and converted into electrical power ready to be utilized by wireless personal electronics.”
By employing the “human gait energy scavenger,” InStep NanoPower believes they can capture up to 20 Watts of lost energy. They have created a system they believe can help with our ever increasing need to power mobile electronics.
“However with the rapid growth of mobile devices the demand for power sources producing watts or tens of watts has acutely increased….To bridge this gap, we have developed a radically new mechanical-to-electrical energy conversion method that is based on reverse electrowetting—a novel microfluidic phenomenon4. Energy generation is achieved through the interaction of arrays of moving microscopic liquid droplets with a novel multilayer thin film. We believe that this approach has a number of significant advantages, over existing mechanical-energy-harvesting technologies, including very high power densities, up to 103 W m−2, ability to directly utilize a very broad range of mechanical forces and displacements, including those not accessible by traditional piezoelectric or electromagnetic methods, and ability to output a broad range of currents and voltages, from several volts to tens of volts without the need for up or down voltage conversion.”
Not only have they created an opportunity to reclaim wasted energy but they have also added what amounts to a WiFi hotspot into the shoes as well. As Android users, we have all learned some battery saving techniques, including staying in range of a WiFi signal as long as possible in order to minimize the need to search for cell towers. InStep NanoPower takes advantage of both the energy and WiFi technology to bring you a significant boost in usable battery life.
“We have also designed a novel energy management system, which allows direct utilization of the generated energy by common mobile devices such as smartphones and does not require connecting wires or mobile device modification. In particular, the integrated Wi-Fi hot spot can act as a “middleman” between mobile devices and a wireless network. Such an arrangement dramatically reduces power consumption of wireless mobile devices and allows them to operate for much longer time without battery recharge. “
Even if InStep NanoPower is only able to collect 50% of the energy lost per foot, 10 Watts is still enough to power a netbook or a Chromebook. Perhaps this is an answer to the fairly significant issue we all face regarding battery technology. InStep NanoPower did not mention when the first pre-production models might be available.