Electric Slide Liquid moves between the bladders. As it does, the flow is converted into electricity. Dave Quaranta

Humans are not very efficient. When we walk, we waste close to 20 watts of energy per second. Instead of turning all calories into lift or forward motion, we turn most of them into heat that’s quickly dissipated. So my colleagues and I came up with a way to harvest the wasted energy from human motion and convert it into about 10 watts of electricity.

Our device is based on a physical phenomenon called electrowetting: If you apply electrical voltage to certain liquids, the liquid moves. This means you have converted electrical energy (the current) to mechanical energy (the liquid in motion). We reversed the process, forcing liquid to move over electrodes. In the shoe, you have two flexible plastic bladders, one under the heel and the other under the toe. The bladders are filled with a mixture of oil and water and connected by a thin, snaking tube. When you step down on your heel, you compress the rear bladder, and several milliliters of liquid travel through the tube to the front bladder. Step on the toe, and the process is reversed.

The tube is lined with a thin film of electrodes, and as the liquid slides back and forth, the electrodes charge—electrowetting in reverse. A small battery stores the energy, and you can access that energy by way of a micro-USB port on the heel of the shoe. We also invented a way, like Wi-Fi, to transfer power from shoe to cellphone battery. Military or police might like having a regular supply of power, but I suspect most people wouldn’t be happy dealing with wires connected to their footwear.

15 Comments

A watt is a unit of power, not energy. 1 watt is 1joule/second.

Cool. But as someone who buys shoes, USB ports are a side thought to comfort and style. My shoes especially need to be very durable - the last thing I would want is oil/water mixture soaking my feet.

Of course I also don't own any portable electrical devices. Someone who is always carrying a phone or tablet or the like would probably be more interested in the power generating shoe. But I really like the thinking behind it - a bit of creative brilliance.

BTW what's the estimate retail price?

When are "they" finally going to pull the trigger on this tech, I've been seeing this same design used with different types of electricity creation methods (piezoelectric effect for example) for 20 years now. "They" just keep reinventing the wheel so to say but never actually produce a working public product.

Playing Devil's Advocate since 1978

"The only constant in the universe is change"
-Heraclitus of Ephesus 535 BC - 475 BC

"We also invented a way, like Wi-Fi, to transfer power from shoe to cellphone battery." -- You had me until "woo".

So, these guys have invented shoe-power and also wireless power transfer, and this is the article announcing it to the world?

Not that I don't love the thought of having wireless power running straight up the length of my body from my feet...

Pretty sure Tesla invented wireless power transfer...

Playing Devil's Advocate since 1978

"The only constant in the universe is change"
-Heraclitus of Ephesus 535 BC - 475 BC

Something tells me the 10 watts is a slight exaggeration. That would mean if you were walking for an hour you could charge your smart phone. Plugging your phone into a wall socket doesn't even do that. Also, you would need a charger in between your shoe and your phone since lithium batteries need a decent amount of regulation to charge safely (aka without rapidly disassembling ... blowing up). Sounds like a lot of stuff to go in the heel of your shoe.

Wireless power has been worked on for a while - "Witricity" comes to mind - the biggest roadblocks to this tech is range and amount of power being delivered. It's just not mature enough yet.

-TC-
Like the article said the military would use it most efficiently. Anyone that has to be put in remote areas of the world with limited power grid access would greatly benefit. A non-intrusive way to generate small supplies of power.

What I wonder is where this power is coming from.. They say that we do not walk efficient and therefore loose 20 Watts of power. But putting this device in your shoe does not necessarily mean that this 'lost' power is converted by their 'invention'.

It might very well be that it now feels like your walking on sand (just to give an example) making it harder to walk thereby making it even less efficient and makes you loose lets say 30 Watts. =P wonder if they tested this or just making a bold claim that it must come from the wasted energy.

Haha wonder how fast you must run for it to charge your laser pistol xD, just kiddin

Now if you apply that clear nano tube coating that absorbs light (not the ultra black/99% absorption coating) but the clear nano tube coating that is being planed on being used on phone screens and windows on the shoes as well as this system you could make more than 20 watts...... Just a thought, although I can't find the Clear Nanotube Tech. Article. I don't remember if it was on here or an Droid Forums or somewhere else but I know it exists???????

Problem is this: You are not only a technology company, you are a shoe designer. What makes you think you can compete with Nike? So what to do? Patent and license the tech. So then you convince a shoe company that an addition cost of $20 per shoe is worth it (remember that you can multiply by a factor of three from cost to shelf price, so maybe $60 per shoe on the shelf). Good luck with that.

I also have a problem with the output power claims. 10 watts is going to cause substantial mechanical damping. Possibly be uncomfortable and affect your gate. Vaporware.

Better than a shoe would be a dr. scholls type insert that would work with any shoe.... that way those who want to use it, could switch shoes whenever and take their power-plant with them.

Idea first heard here... intellectual rights reserved by me.

better yet. a removeable battery that could be charged and removed and used witout being conected to the shoe.
intellectual rights reserved by me
must credit/source for use.

Connected Heel & Toe Chambers inside of the Shoe with Fluids used to generate electricity is Patented invention by the Cosmopolitan Exchange Corp. This discussion is illegal since it is infringing on the Intellectual Property of the Cosmopolitan Exchange Corp. I am requesting the Popular Science to stop this immediately. Thank you! Mario Mark



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