Engineers say, when you’re on the go and your smartphone battery is low, just wait.  In the not-so-distant future you could charge your phone.  Uniquely, by simply plugging it into your power generating shoes for energy optimization.

An innovative energy harvesting and storage technology developed by University of Wisconsin-Madison mechanical engineers.  Comparatively, this product would reduce our reliance on the batteries in our mobile devices. Thus, ensuring we have power for our devices no matter where we are. Power generating shoes are just a start.

Engineers Capture the Motion Energy Walking

Energy Optimization will take  technology could enable a footwear-embedded energy harvester. Capturing energy produced by humans during walking, thus, storing it for later use. Engineers could develop power generating shoes.

Power-generating shoes could be especially useful for the military.  Soldiers currently carry heavy batteries to power their radios, GPS units and night-vision goggles in the field. Similarly, this advance could provide a source of power to people in remote areas and developing countries that lack adequate electrical power grids.

Engineers say human walking carries a lot of energy.  Theoretical estimates show that it can produce up to 10 watts per shoe, that energy is just wasted as heat. A total of 20 watts from walking is not a small thing.  Compared to the power requirements of the majority of modern mobile devices.

Engineers say tapping into just a small amount of that energy is enough to power a wide range of mobile devices, in the power generating shoes.  Together with, Smartphones, tablets, laptop computers and flashlights. For example, a typical smartphone requires less than two watts.

Engineers Convert Motion to Energy

However, traditional approaches to energy harvesting and conversion don’t work well for the relatively small displacements.  Large forces of “footfalls”, according to the researchers.   https://www.bbc.com/news/science-environment-30816255

Engineers have been developing new methods of directly converting mechanical motion into electrical energy.  Also, appropriate for this type of application for the power generating shoe.

The Engineers new energy-harvesting technology takes advantage of  reverse electrowetting.  A phenomenon pioneered 2011. With this approach, as a conductive liquid interacts with a nanofilm-coated surface  Mechanical energy is directly converted into electrical energy.  https://glewengineering.com/engineers-develop-awesome-ways-drones-can-be-used/

Engineers Develop Electrowetting Power Method

The reverse electrowetting method can generate usable power.  It does require an energy source with a reasonably high frequency.  Such as a mechanical source that’s vibrating or rotating quickly.

Our environment is full of low-frequency mechanical energy sources such as human and machine motion, and our goal is to be able to draw energy from these types of low-frequency energy sources. Reverse electrowetting by itself didn’t solve one of the problems they had. To overcome this, the researchers developed what they call the “bubbler” method.   The bubbler method combines reverse electrowetting with bubble growth and collapse.

The Engineers bubbler device, which contains no moving mechanical parts. Consisting of two flat plates separated by a small gap filled with a conductive liquid. A bottom plate is covered with tiny holes through which pressurized gas forms bubbles. The bubbles grow until they’re large enough to touch the top plate, which causes the bubble to collapse. The speedy, repetitive growth and collapse of bubbles pushes the conductive fluid back and forth, generating electrical charge.    https://glewengineering.com/engineers-design-airports-of-the-future/

High frequency that you need for efficient energy conversion isn’t coming from your mechanical energy source but instead, it’s an internal property of this bubbler approach.

Engineers Develop Bubbler Energy Method

Engineers say their bubbler method can potentially generate high power densities to power generating shoes. Lots of watts relative to surface area in the generator. Which enables smaller and lighter energy-harvesting devices.  Conversely coupled to a broad range of energy sources. The proof-of-concept bubbler device generated around 10 watts per square meter in preliminary experiments.  Theoretical estimates show that up to 10 kilowatts per square meter might be possible.

The bubbler method really shines at producing high power densities.  Ultimately, for this type of mechanical energy harvesting, the bubbler has a promise to achieve by far the highest power density ever demonstrated.

Engineers Say Motion Integrated

Again,  Engineers could directly power various mobile devices through a charging cable.   Moreover, abroad range of electronic devices could be integrated. Embedded in a shoe, such as a Wi-Fi hot spot that acts as a “middleman” between mobile devices and a wireless network. The latter, requires no cables, dramatically cuts the power requirements of wireless mobile devices.  This can make a cellphone battery last 10 times longer between charges.https://glewengineering.com/technology-advanced-driver-assistance-systems/

Ultimately,  just the energy cost of radio-frequency transmission back and forth between the phone and the tower is a tremendous contributor to total drain of the battery.  Engineers are always developing new ways to make a better world.