Wearables

In-shoe device harvests energy created by walking

A new in-shoe device is designed to harvest the energy that is created by walking, and store it for use in mobile electronic devices
A new in-shoe device is designed to harvest the energy that is created by walking, and store it for use in mobile electronic devices
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A new in-shoe device is designed to harvest the energy that is created by walking, and store it for use in mobile electronic devices
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A new in-shoe device is designed to harvest the energy that is created by walking, and store it for use in mobile electronic devices
The shoe energy-harvesting system utilizes a microfluidic device containing thousands of tiny droplets
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The shoe energy-harvesting system utilizes a microfluidic device containing thousands of tiny droplets
The shoe energy-harvesting system utilizes a microfluidic device containing thousands of tiny droplets
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The shoe energy-harvesting system utilizes a microfluidic device containing thousands of tiny droplets
The shoe energy-harvesting system utilizes a microfluidic device with a nanostructured surface
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The shoe energy-harvesting system utilizes a microfluidic device with a nanostructured surface
The shoe energy-harvesting system utilizes a microfluidic device with a nanostructured surface
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The shoe energy-harvesting system utilizes a microfluidic device with a nanostructured surface
A new in-shoe device is designed to harvest the energy that is created by walking, and store it for use in mobile electronic devices
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A new in-shoe device is designed to harvest the energy that is created by walking, and store it for use in mobile electronic devices

Although you may not be using a Get Smart-style shoe phone anytime soon, it is possible that your mobile phone may end up receiving its power from your shoes. University of Wisconsin-Madison engineering researchers Tom Krupenkin and J. Ashley Taylor have developed an in-shoe system that harvests the energy generated by walking. Currently, this energy is lost as heat. With their technology, however, they claim that up to 20 watts of electricity could be generated, and stored in an incorporated rechargeable battery.

While the details of the energy-harvesting technology are proprietary, it is said to involve a process known as "reverse electrowetting," which was discovered by Krupenkin and Taylor. It converts mechanical energy to electricity via a microfluidic device, in which thousands of moving microdroplets (of an undisclosed non-toxic, inexpensive liquid) interact with "a groundbreaking nanostructured substrate." The process is said to have a power density of up to one kilowatt per square meter (10.76 sq. ft.), plus it works with a wide range of mechanical forces, and is able to output a wide range of currents and voltages.

The battery is hermetically sealed, for protection against water and dirt. In order to get the power from it to the phone or other mobile device, the two would have to be temporarily physically joined with a wire, although the researchers are also looking into the use of conductive textiles and wireless inductive coupling.

A new in-shoe device is designed to harvest the energy that is created by walking, and store it for use in mobile electronic devices
A new in-shoe device is designed to harvest the energy that is created by walking, and store it for use in mobile electronic devices

Besides directly powering the phone, the device could also serve as a mobile WiFi hotspot, linking the phone to a wireless network. Having its own hotspot constantly nearby could drastically increase the phone's battery life - this is because the phone would only need to transmit in a low-power standard such as Bluetooth in order to reach the device, which would then use its own battery (which would be continuously getting recharged, by walking) for the high-power long-range transmissions to the network. Krupenkin claims that this could allow phone batteries to last up to ten times longer than normal.

The U Wisconsin technology is currently in the process of being commercialized, through Krupenkin and Taylor's company, InStep NanoPower. If it does make it to the marketplace, it may have some competition - Dr. Ville Kaajakari is also developing a piezoelectric device for shoes, that generates power as its user walks.

16 comments
Mr Stiffy
I mean this is good, and all that - but I am starting to hate tech and tech stories about bullshit devices... They get to the point where they are clever applications and ideas - that become applied in stupid ways. In almost all applications - power sources such as \"the grid\" based battery chargers, solar cells - in either the roof system, portable folding panels or top up units on the back pack seem to cover all bases. Even when walking to the north or south pole with sled in tow - a portable 500gram wind generator and or fuel cell will keep a charge in the camcorder / satellite phone / GPS / tent light / torches. It\'s crap like this - along with gravity activated pencil sharpeners, or See Through Time Amathyist Crystals from Atlantis... A small 5 x 10 cm or 20 x 30 cm solar panel on the back pack, and only turn on the gear when you need it - I can believe and use that - especially is your on a 10 day hike across the mountains - with no car etc near by. But I ask \"Don\'t the people who ever make this crap - ever really think about this, and it\'s practical value being over ridden by it\'s irritation / draw backs / lack of real world use?
livin_the_dream
Personally I think it\'s great, just think, when Batman needs his cape energised, lol....
Slowburn
Shoes that can recharge your cell phone sound like a good idea to me.
Mike Thompson
Run faster,I can not hear you!
windykites
What happens when the shoe wears out? They are not going to be cheap. A small solar cell seems like a better solution
Gurney Halleck
Finally! I really need this for my stillsuit. Now, if I can just find a reliable ornithopter...
Zachary Cochran
This isn\'t going to go over well with the TSA...
Mr Stiffy
Oh really - thought about this some more. You mean people are going to go out and especially buy self charging shoes (= expensive and heavier), and Then they are going to be walking miles every day (good idea), and Then they are either going to take off their shoes and plug their mobile phones etc., into them, OR Walk around with their mobile phones in their pockets and wires running down the inside of their trouser legs or bare legs if they have a skirt on (conjures up some interesting ideas) all the way down to a connector on the shoes...... And I am thinking \"You really expect people to go along with any of that?\" Power point and charger on the wall - or a small solar cell on the back pack - and while I am hiking through the mountains and it\'s freezing cold in the late afternoon - with dangerous tribes of Drop Bears in the trees, and you expect me to buy shoes that I have to take off to plug my mobile phone / GPS / torch into? It\'s just not going to happen.
Pinhead
The title should have been, \"In-shoe device helps wearers exercise by making walking less efficient\". Humans do not have surplus energy to waste.
wle
no not 20 watts! i;d believe 2, or 5, for short instants i agree with Mr Stiffy : seems like a solar cell would be a lot more convenient also it would not break, or have to be replaced when the shoes wore out plus, the shoes would have to be to everyone;s liking and how likely is that? esp for hikers, etc - they like their OWN favorite shoes not these weird things also who wants wires on their legs? or having to take off your shoes and fiddle with plugs, adapters, etc, to run or recharge some battery? wle
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