Replacing batteries may become a thing of the past, thanks to 'soft generators'

Apr 06, 2011
This image shows a hand-pumped soft generator the researchers are using to demonstrate it. Credit: N/A

Battery technology hasn't kept pace with advancements in portable electronics, but the race is on to fix this. One revolutionary concept being pursued by a team of researchers in New Zealand involves creating "wearable energy harvesters" capable of converting movement from humans or found in nature into battery power.

A class of variable capacitor generators known as "dielectric elastomer generators" (DEGs) shows great potential for wearable harvesting. In fact, researchers at the Auckland Bioengineering Institute's Biomimetics Lab believe DEGs may enable light, soft, form-fitting, silent energy harvesters with excellent mechanical properties that match human muscle. They describe their findings in the American Institute of Physics' journal .

"Imagine soft generators that produce energy by flexing and stretching as they ride ocean waves or sway in the breeze like a tree," says Thomas McKay, a Ph.D. candidate working on soft generator research at the Biomimetics Lab. "We've developed a low-cost power generator with an unprecedented combination of softness, flexibility, and low mass. These characteristics provide an opportunity to harvest energy from environmental sources with much greater simplicity than previously possible."

Dielectric elastomers, often referred to as artificial muscles, are stretchy materials that are capable of producing energy when deformed. In the past, artificial muscle generators required bulky, rigid, and expensive external electronics.

This is a schematic of the physical layout of the soft generator. Credit: N/A

"Our team eliminated the need for this external circuitry by integrating flexible electronics—dielectric elastomer switches—directly onto the themselves. One of the most exciting features of the generator is that it's so simple; it simply consists of rubber membranes and carbon grease mounted in a frame," McKay explains.

McKay and his colleagues at the Lab are working to create soft dexterous machines that comfortably interface with living creatures and nature in general. The soft generator is another step toward fully soft devices; it could potentially be unnoticeably incorporated into clothing and harvest electricity from human movement. When this happens, worrying about the battery powering your cell phone or other portable electronics dying on you will become a thing of the past. And as an added bonus, this should help keep batteries out of landfills.

Explore further: Exploring X-ray phase tomography with synchrotron radiation

Provided by American Institute of Physics

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SteveL
1.6 / 5 (19) Apr 06, 2011
There is still an inital source of energy (food) required, and it's not all that effecient of a conversion method (food to movement). Just imagine if Sony came back with the Walkman and it was powered by your shoes. No walking, no music.

I'd file this under "interesting but impractical". After all, every TV comes with a remote now days for a reason. One more thing for the landfill.
CHollman82
3.7 / 5 (7) Apr 06, 2011
@SteveL

I really don't think you understand...

Sure, you can't put a shirt with this incorporated into it on a comma patient and expect to get much energy out, but for any reasonably alive and alert human you can expect a certain degree of movement, even when "idle". The low conversion efficiency isn't all that important when it is currently zero. If I could pay an extra $30-50 per article of clothing in order to extend the battery life of my phone by as little as 10% per charge I would do so happily.
LincolnSixEcho
1.2 / 5 (6) Apr 06, 2011
And... what happens when you're outside and it rains?
DozerIAm
1.7 / 5 (12) Apr 06, 2011
SteveL has a valid point - there is no free energy. If you wear it like clothing, it will take you more energy to do what it is you are doing (less it's conversion factor, too). Which will mean you will need to eat more food and exert yourself more to accomplish the same things. Batteries will probably be overall less expensive and more practical, overall.

Its kind of like that light I had on my bicycle as a kid that had a generator powered off the read wheel. It slowed the bike down so much and made it so much harder to pedal that I took it off. Wasn't worth the effort. I suspect the same will be true here as well.
Royale
4.3 / 5 (8) Apr 06, 2011
Either you misinterpret or your argument made absolutely no sense. They were words that formed your sentences. And you're also correct in stating that the conversion is inefficient. Your completely wrong in interpreting the practicality. The idea is that you'll have a battery you can still charge like normal, but also built into your pants, perhaps, would be these soft generators that use the movements that you are going to make anyway to use as electricity. All they are doing is effectively wanting to conserve spent energy and not let it pass into the environment unused. These generators help maintain power in your battery. They aren't the only source of power for your device; otherwise, it wouldn't have said "battery power" they would have had to phrase that differently.
As for the landfill comment: I don't know for sure what they mean, but I'd imagine they're referring to the slower charge rate making the battery last longer as we commonly see in batteries now.
whalio
3.5 / 5 (16) Apr 06, 2011
Steve, dozer, you guys take 1st and 2nd place, respectively, for the dumbest comments I've ever read.
CHollman82
4.4 / 5 (12) Apr 06, 2011
If you wear it like clothing, it will take you more energy to do what it is you are doing (less it's conversion factor, too). Which will mean you will need to eat more food and exert yourself more to accomplish the same things. Batteries will probably be overall less expensive and more practical, overall.

Its kind of like that light I had on my bicycle as a kid that had a generator powered off the read wheel. It slowed the bike down so much and made it so much harder to pedal that I took it off. Wasn't worth the effort. I suspect the same will be true here as well.


No...

You use energy to move your clothing around already... sure this may add a TINY degree of extra resistance but so what? You won't even notice it if it is implemented correctly. You ALREADY use energy to "push" your clothing around when you move, and some of this energy is lost to the environment (frictional heating at least).
DozerIAm
1.9 / 5 (14) Apr 06, 2011
No...

You use energy to move your clothing around already... sure this may add a TINY degree of extra resistance but so what? You won't even notice it if it is implemented correctly. You ALREADY use energy to "push" your clothing around when you move, this energy is lost to the environment (probably generating heat through friction). Instead this will collect it.


Its extra resistance. Unless you are on that development team or have access to their calculations, you (like I) have no idea how efficient or inefficient this technology is.

I suspect you are idealizing the potential. That's a fun thing to do, but I was speculating about its likely real world development possibilities in the near term. Which is, as I suggested before, a novelty - much like those friction generator bicycle lights.
CHollman82
4 / 5 (9) Apr 06, 2011
Its extra resistance. Unless you are on that development team or have access to their calculations, you (like I) have no idea how efficient or inefficient this technology is.

I suspect you are idealizing the potential. That's a fun thing to do, but I was speculating about its likely real world development possibilities in the near term. Which is, as I suggested before, a novelty - much like those friction generator bicycle lights.


I hope it does add a bit of resistance... I'll extend the life of my phone while staying in shape a little easier. Perhaps there could be multiple versions that allow you trade off resistance of the material with energy generation capacity. Either way it may be in it's infancy but it will be much more than a novelty if it ever becomes fully realized.
DozerIAm
3.7 / 5 (3) Apr 06, 2011
I hope it does add a bit of resistance... I'll extend the life of my phone while staying in shape a little easier. Perhaps there could be multiple versions that allow you trade off resistance of the material with energy generation capacity. Either way it may be in it's infancy but it will be much more than a novelty if it ever becomes fully realized.


Now that's a comment I can respect. I don't share your interest in having such a product if it involves extra resistance but I get that you do. Thanks for the level response.
A_Paradox
4.3 / 5 (6) Apr 06, 2011
I am really disappointed in most of the comments made so far.
I see this invention to have enormous potential for good.
The authors mention not having to worry all the time about recharging the batteries of gadgets we carry around. That is a genuine issue. The fact that it might take a little extra energy walking around is no big deal; most US Americans eat too much already, same for most Aussies and Brits also I think. Only good can come from over-fed people having to expend more muscular effort.

Batteries in land fill are a major threat for pollution of ground water; and that is a BIG issue. In addition, if less recharging devices are needed then less energy will be taken from fossil fuels; that is another significant benefit.
A_Paradox
5 / 5 (2) Apr 06, 2011
With regard to bicycle dynamos, the problem in the one's we used to have when I was a kid was that they pressed on the side of the tyre. This meant they had to have a heavy spring, which was sometimes hard for kid's fingers to operate. Also the traction of the capstan head was reduced in wet weather so the light faded at just the wrong time. Also the magnets and armatures were probably not the most efficient of designs.
In the late '80s I bought a dynamo that pressed onto the tread of the tyre and it had good grip and the resistance I felt was much less than for the old side-presser type. It was really effective at night riding home from work and utterly dependable in the wet when it was particularly needed. I was really pissed off to find that they were no longer being manufactured so I couldn't replace it with the same. I was hoping to get a hub dynamo for my front wheel when ordering my most recent bike, but none could be found.
Quantum_Conundrum
3.9 / 5 (7) Apr 06, 2011
*sigh*...more of this...

This might be useful some sort of medical sensor that requires a ridiculously low amount of power, but it is NOT going to power your Cell Phone.

For goodness sakes...

1 Day:
2000 food calories = 8400000Joules

8400000Joules / 86400Seconds = 97.22Watts

This is how much power your body uses, most of it is brain, heart, and lungs.

I showed on another thread that even if you moved CONSTANTLY, there is no way you'd ever be able to charge a modern cell phone with this, because the charger couldn't possibly be efficient enough, and there isn't enough available energy in your body movements to charge it as fast as you'd need, and that was assuming 24 hours of continuous motion. You aren't moving around nearly as much as you think.

sleep
eating (little movement)
sitting in front of a computer
driving (little movement)
DozerIAm
3.3 / 5 (6) Apr 06, 2011
Rational thought and logical reasoning will get you nowhere here, QC - you should know that. :p
SteveL
2.2 / 5 (5) Apr 06, 2011
Steve, dozer, you guys take 1st and 2nd place, respectively, for the dumbest comments I've ever read.

Fortunately facts don't really care about opinions.

If indeed they are talking about eliminating the battery in personal electronics then you will have to continuiously and without hesitation provide the needed power. Hence, my comment about the Walkman. When you stop activity, you stop generation of power and your device quits. The vast majority of our population would not be interested in this as the trend is towards making things easier (less work).
CHollman82
3 / 5 (4) Apr 06, 2011
Steve, dozer, you guys take 1st and 2nd place, respectively, for the dumbest comments I've ever read.

Fortunately facts don't really care about opinions.

If indeed they are talking about eliminating the battery in personal electronics then you will have to continuiously and without hesitation provide the needed power. Hence, my comment about the Walkman. When you stop activity, you stop generation of power and your device quits. The vast majority of our population would not be interested in this as the trend is towards making things easier (less work).


No one is talking about this... Do you really think this is intended to be used absent of a battery?
J-n
5 / 5 (4) Apr 06, 2011
My watch is powered by the movement i make throughout the day without my watch stopping. I dont notice a difference in weight or size from other watches.

Personally i think it would be a great thing to have (even if only generating a small ammt of power) it would be nice to get something from my nervous habbit of shaking my leg.
sams
2 / 5 (4) Apr 06, 2011
"This is how much power your body uses, most of it is brain, heart, and lungs."

I don't think so:

Total: approx. 100 watts

Brain: approx. 20 watts
Heart: approx. 1-5W watts
Lungs: (haven't found a reference - I'd guess about 5 watts)
So these a only slightly more than 25% of power consumption.

On the other hand, my 4 watt charger charges my phone in about an hour, and I only need to do this once every few days. Continuous charging during waking hours (16 hours per day) would require perhaps as little as 0.05 watts = 50 milliwatts.
CSharpner
2 / 5 (4) Apr 06, 2011
1 Day:
2000 food calories = 8400000Joules

8400000Joules / 86400Seconds = 97.22Watts

This is how much power your body uses, most of it is brain, heart, and lungs.

I showed on another thread that even if you moved CONSTANTLY, there is no way you'd ever be able to charge a modern cell phone with this, because the charger couldn't possibly be efficient enough, and there isn't enough available energy in your body movements to charge it as fast as you'd need, and that was assuming 24 hours of continuous motion. You aren't moving around nearly as much as you think.


Excellent post QC! This is the kind of stuff I've noticed you're particularly good at: Look at the big picture and run the numbers... not so much on other things (no offense).

I fived you! I don't usually do that on your posts, but every now and then, you've got some really good posts. Keep'em coming and I'll five you more and it may cancel out the 1's I've been giving you. ;)
Moebius
3 / 5 (2) Apr 06, 2011
To QC, how much energy we use is irrelevant, we would have to do extra work to power the generator. Nothing new there, people have been doing physical labor since day one, it's called work and it produces and uses a lot more energy than sitting at a desk.

Probably the most efficient would be in a shoe using our weight to push something like a plunger. On a level surface this would still have the effect of essentially going uphill on a slight grade. Each step would be like going up a staircase with very low steps. A lot of energy could be generated by doing work like this. Didn't you see Conan the Barbarian? Before he was freed he was turning the mill wheels by himself. Probably generating hundreds of thousands of Hollywood psuedokilojoules.
SteveL
not rated yet Apr 06, 2011
No one is talking about this... Do you really think this is intended to be used absent of a battery?

Quote from the article:
And as an added bonus, this should help keep batteries out of landfills.

Batteries don't really care what charges them provided enough of the right type of power is available, so the only way to keep batteries out of the landfills is to not have them in the devices in the first place. If this is just a potential technique to charge batteries, it would have no or possibly even an adverse effect on the number going to landfills. Some batteries are limited on their number of charge/discharge cycles. In such cases even a partial charge and discharge limits the battery life. Unless you are willing to expend energy until the battery is fully charged you will lessen its life expectancy.
SteveL
not rated yet Apr 06, 2011
Concerning the human energy expended. I think we can agree that this implies the burning of calories - more calories than presently used. These calories come from food. More food required means more energy expended to plant, cultivate, fertilize, harvest, store, process, transport, retail, shop for, prepare and eat the extra food. How much new CO2 does this add to the process that would not have been required before? All sources of energy have a cost.
Quantum_Conundrum
2.5 / 5 (2) Apr 06, 2011
sams:

"The mechanical power of the human heart is ~1.3 watts. It takes a much higher rate of energy turnover (~13 watts) to provide this mechanical power, since the mechanical efficiency of the heart is very low (less than 10%)"

So your heart has an OUTPUT of 1.3 watts, but has an input of 13watts, since it is about 10% efficient.

hypertextbook.com/facts/2003/IradaMuslumova.shtml

The energy used to digest food is about 10% of that taken in...

greenanswers.com/q/89548/health/general/does-our-digestive-system-use-more-energy-respiratory

Respiration is a bit complicated. In cellular respiration, apparantly 38 ATP is produced in one cycle, but 8 ATP is consumed during the cycle for respiration itself, therefore cellular respiration consumes 21.05% of the energy it produces...

However, cellular respiration doesn't translate well to the idea of "breathing" and how much it takes for you diaphragm to work the lungs, which I too have not been able to find.
Quantum_Conundrum
2.8 / 5 (4) Apr 06, 2011
So:

Brain: 20%
Heart: 13Watts
Digestion: 10%
Respiration*: More than 6.5 watts (Possibly 13 watts or more)
Total: significantly more than 49.5 watts

Don't forget the other major organs such as the lymph/spleen, kidneys, liver, pancrease, bladder, etc...

*Using the amount of air we actually breathe, and assuming a half meter of displacement from the bottom of the lungs to the nostrils we find the minium work required to move air up and out of the lungs. We breathe in/out 11.1456kg of air per day. Using pressure, I was able to calculate that the diaphragm has an output of at least 6.51 watts just to move air ONE way. Thus if it were an ideal machine it would use only 6.5 watts, but it is less than ideal...
Quantum_Conundrum
2.8 / 5 (4) Apr 06, 2011
Now since 21% of the energy produced in cellular respiration is consumed by the cellular respiration cycle itself, and since your lungs use AT LEAST 6.5watts to 13watts just to bring in the air, then we wave:

97 watts - 6.5watts to 13 watts = 91.5watts to 85watts

21% of 91.5watts = 19.215 watts

21% of 85watts = 17.85 watts

So now when you add the energy consumed by cellular respiration in the process of cellular respiration BACK TO the energy used by the lungs in bring the air into the body in the first place, we have:

from: 6.5 + 19.215 = 25.715 watts

To: 13 + 17.85 = 30.85 watts

So all together, with round numbers, "Respiration" actually uses 26 to 31 Watts out of the 97 watts food and respiration combined actually produce.
Quantum_Conundrum
2.8 / 5 (4) Apr 06, 2011
So that brings our new total on "non-movement energy" excluding other movements of other organs in the body to:

brain: 20
Heart: 13
Lungs: 6.5 to 13
Cellular respiration: 19 to 18
Digestion: 10
Total: 68.5watts to 74watts
Neurons_At_Work
5 / 5 (3) Apr 06, 2011
Interesting thread... I double-checked the math and it appears correct, and yet-- I have a 10 year old crank type emergency FM radio with a main spring geared to a small generator. 45 seconds of moderate cranking winds the spring, then the spring spins the generator as it slowly unwinds and plays the radio loudly for roughly 20 minutes. If this same cranking effort were spread over 16 hours I wouldn't notice it at all. Math notwithstanding, it seems that that much energy could surely add a few extra hours to my Blackberry. Or, I could be completely out in left-field...
bugmenot23
1 / 5 (1) Apr 07, 2011
In the near future, if average Americans don't arise from their stupor, repugnican plutocrats will require all liberals to wear soft generators (probably made by irradiated Japanese kids at a Kathie Lee Gifford sweat shop) in order to justify their societal value. Enuff Said? ;)
Beard
3 / 5 (4) Apr 07, 2011
1 Day:
2000 food calories = 8400000Joules

8400000Joules / 86400Seconds = 97.22Watts

This is how much power your body uses, most of it is brain, heart, and lungs.

I showed on another thread that even if you moved CONSTANTLY, there is no way you'd ever be able to charge a modern cell phone with this


Ever use a rowing machine at the gym? You pull the cable and push with your feet while seated to spin a resisting flywheel.

You're saying that all of that energy isn't even enough to power a phone? Seems kind of bizarre.
antialias_physorg
4.2 / 5 (5) Apr 07, 2011
It will take you more energy to do what it is you are doing (less it's conversion factor, too). Which will mean you will need to eat more food

No. It will just mean that what is now radiated away as heat (through friction/movement of the fabric) is then captured (partially) as a usable form of energy. No additional food intake required.
Jimbaloid
not rated yet Apr 07, 2011
Maybe we will just have a landfill full of soft generator clothing instead. Because it was snagged, stained, wrong colour, fashion...

They do talk of other ways of using it that are not clothing based and perhaps more practical.
sams
4.5 / 5 (4) Apr 07, 2011
@QC: Your initial implication ("for goodness sakes") that people are stupid to believe there is enough energy left over in human motion to produce the tens millwatts require to charge a 4 watt-hour batteries over a number of days fell flat a bit. Even with your (alleged) calculations, with their results (displayed in absurdly overstated accuracy), you have not managed to show this.

I'm fairly sure that the lungs would do less work than the heart does pumping all of that liquid blood around the body. I'm inclined to believe this figure: (output) power of ~ 1 watt:
http://www.ncvs.o...dex.html
CHollman82
2.5 / 5 (2) Apr 07, 2011
No one is talking about this... Do you really think this is intended to be used absent of a battery?

Quote from the article:
And as an added bonus, this should help keep batteries out of landfills.


You think the only way to HELP keep batteries out of landfills is to stop using them entirely? How about using them LESS?
Quantum_Conundrum
3.7 / 5 (3) Apr 07, 2011
sams:

Milliwatts don't mean JACK compared to a WATT-HOUR.

4 watt-hours means that you have a power supply of 4 watts for one hour, OR a power supply of 1 watt for 4 hours, or any multiplicative combination totalling 4.

Either way, 4 watt-hours equals 14,400Joules.

To get that much energy from a 1 milliwatt generator in your clothing would take 167 days.

Beard:

Exercising uses more energy because it burns more calories. People who work out regularly eat a LOT more food and breathe a lot more all together compared to people who do not work out as often.

You even help prove the point that in order to charge something like this requires constant work/motion, and the larger and more rapid the motions the better.

Your clothes hardly move at all while you are just sitting or standing or typing and similar things.
Quantum_Conundrum
3.7 / 5 (3) Apr 07, 2011
So anyway, to educate certain people on this thread...

A "Watt" is not a unit of energy, it is a unit of POWER.

The number of Watts tells you how many JOULES(energy) your device consumes or produces PER SECOND.

"Watt-hours" is the multiple of POWER and TIME to get ENERGY.

So 4 watt-hours is 14,400 Joules.

A kilowatt-hour is 3,600,000 Joules.

A milliwatt class generator is insignificant compared to your cell phone's energy needs.
SteveL
not rated yet Apr 07, 2011
No one is talking about this... Do you really think this is intended to be used absent of a battery?

Quote from the article:
And as an added bonus, this should help keep batteries out of landfills.

You think the only way to HELP keep batteries out of landfills is to stop using them entirely? How about using them LESS?

That is an option, but history has shown that the demand has been rising sharply for personal electronics and the batteries that power them. Another option (my preference) is to continue to make electronics more effecient - and preferrably more environmentally friendly and recyclable.
sams
5 / 5 (1) Apr 07, 2011
QC: "Milliwatts don't mean JACK compared to a WATT-HOUR."

Shouting doesn't improve your argument one bit.

QC: "So anyway, to educate certain people on this thread..."

Having been availed of a PhD in particle physics since the early nineties, I have a reasonable idea of such things.

"To get that much energy from a 1 milliwatt generator in your clothing would take 167 days."

Now you are just picking silly numbers. See above where I said: "Continuous charging during waking hours (16 hours per day) would require perhaps as little as 0.05 watts = 50 milliwatts."

You don't seen to be aware that phone battery capacities are commonly quoted in watt-hours. I'm not sure why you take exception to the term.

"Your clothes hardly move at all while you are just sitting or standing or typing and similar things."

No everyone is a pimply couch potato that wears diapers so they don't have to get up though.
SteveL
not rated yet Apr 07, 2011
It will take you more energy to do what it is you are doing (less it's conversion factor, too). Which will mean you will need to eat more food

No. It will just mean that what is now radiated away as heat (through friction/movement of the fabric) is then captured (partially) as a usable form of energy. No additional food intake required.
Ah, if they had been talking about cloth that used the body's radiated heat to generate power, that's different. Depending on several factors the adult body can produce from 80 - 150 watts of heat energy.
physpuppy
not rated yet Apr 07, 2011
:-) :-)

No. It will just mean that what is now radiated away as heat (through friction/movement of the fabric) is then captured (partially) as a usable form of energy. No additional food intake required.


...

Puts down Big Mac.

Darn.

Interesting discussions here on all sides, but all speculation - how it feels, how it works wouldn't be known until there is a working model that we can try out.

Heck if it turns out to be stiffer fabric, well then that might just do away with the need for starch in shirts, no?
lurch
not rated yet Apr 07, 2011
Clothes that generate electricity will be as chic as mobile phone belt holsters. It is useful to have materials that generate electricity however material that generates power will naturally provide more resistance than an equivalent non-power generating material and so will be a burden. If your demands are light then just have a solar cell hat or make a wind-up generator in black so it will go with any outfit. Of course if you wanted to be vaguely practical make an exo-skeleton with regenerative braking. Then when you jump off a tall building the batteries get charged instead of you breaking your legs.
HealingMindN
4 / 5 (1) Apr 07, 2011
I'm also thinking those DEG clothes would look very space age. For me, it's just another reason to get out and boogie. I guess the couch potatoes here don't like the idea, but remember the DEGs can be placed on anything that moves like trees or animals. Get a custom outfit for your wife and send her shopping. You know she'll light up the city.
unknownorgin
1 / 5 (1) Apr 08, 2011
I have experimented with many types and sizes of rechargable batteries and found that below a certain power level a battery will not charge no matter how long it is connected to a power source. To reverse the electrochemical reaction in the battery (charging) requires a minimum voltage that can only be reached at a certain current level determined by the plate area of a battery. The type of generator in this article is good for generating high voltage at very low current just like a van de graf generator but it has too much internal resistance to generate enough current to charge a cell phone battery. An example of a generator with low internal resistance is the alternator in your car, it puts out enough current to charge the battery and power all the electrical accesories too.

antialias_physorg
1 / 5 (1) Apr 08, 2011
Set them up in parallel.
SteveL
2 / 5 (2) Apr 08, 2011
I guess the couch potatoes here don't like the idea,


I ran 3 miles and walked another mile yesterday after work. Not exactly a couch potato as a 50+ yr old. I find the concept interesting, but just don't think it's practical or that the public will go for it en-masse.
A_Paradox
5 / 5 (1) Apr 08, 2011
I think the nay-sayers here are not considering the needs and conveniences of bush walkers, hikers, building construction workers, etc in their own countries or the needs of people in other countries who live in rural communities, who don't have cars and often don't have convenient electricity supplies.

I think that 'smart' clothing incorporating dielectric elastomer generators (DEGs) and shoes with same or with piezoelectric generators in the heels could very well generate the 4 or 5 watts needed to keep lithium batteries charged. It may be that charge is first supplied incrementally to capacitors before being released into the batteries. Soon all these different devices will be endowed with sophisticated 'homeostatic' computing power which will be able to regulate the energy throughput and adjust usage to fit in with [local - on the body] supply and demand.

pauljpease
not rated yet Apr 09, 2011
QC, I feel like you magically switched your argument. First, you focus on how much energy the human body uses, suggesting it's not enough. But that is obviously wrong. Then you switch to, "well, a 1 mW generator would take too long to charge". Sure, but we're not talking 1 mW. 50 mW would be sufficient. Let's all agree that the 2,000 calorie diet an average person eats contains more than enough energy to power a cell phone (including conversion efficiency, we're talking ~1% of your food intake for the day).

Which brings me to my other idea, does anyone remember that they developed fuel cells that run on glucose, and can be implanted in arteries? I'm waiting for that technology to mature, so I can just plug my TV into my gut, down some potato chips and sugary beverages and get thin! What American wouldn't want that? The more TV you watch, and the bigger your TV, the more you can eat without gaining a pound.
sams
not rated yet Apr 09, 2011
QC bailed some time ago. Let's also not forget that calorie intake in not some fixed quantity, but can vary depending on your age, gender and activity levels. Somewhere in 2000-2500 is just the recommended intake. Even allowing for conversion losses, I don't expect an extra 50 milliwatts is much more food.
Ulg
not rated yet Apr 09, 2011
Top athletes consume up to 50,000 Cal/day, while most of us putter away at 2-2.4 kCal/d there is a decent amount of people in between that. At least sport clothing manufacturers stay in business. While not everyone is a walking 2.4kW/h bio reactor some are and developments like his might help inspire people to be a bit more active.
beelize54
1 / 5 (3) Apr 10, 2011
I saw many people with battery lamp on their bicycle, but no one with old-styled dynamo lamp. I think, it says it all about usefulness of this research.
MediocreSmoke
3.7 / 5 (3) Apr 10, 2011
The amount of fake education and wrong information stated as fact here is depressing. Thankfully none of you are in charge of actually advancing science or finding applications for innovation.
unknownorgin
2.5 / 5 (2) Apr 12, 2011
LEDs make little solar cells, speakers put out power around loud sound , a copper and iron wire twisted together, a lemon with a copper and iron wire stuck in it, a microphone, rubbing a balloon on your hair, a penney and nickle in salt water, The list of things that make electricity is very long, are they practical? are they cost effective? Read about why THomas edison DC power system lost out to the westinghouse AC system, learn OHMs law, Take a few electronics courses, spend over 30 years expirmenting with electronics and then you will see this type of generator is not right for charging batterys.
It would be like trying to pull a semi truck trailer with your car. Who in thier right mind would want to wear stiff heavy generator clothes on a nice hot 100 degree summer day anyway?