Talk-Powered Cell Phones Won't Need Batteries 197
alphadogg writes "It's possible that in the future conversations on your cell phone could generate enough electrical power to run the phone, without batteries.
That's one possible outcome of recent work by a team of Texas researchers, who appear to have discovered that by building a certain type of piezoelectric material to a specific thickness (about 21 nanometers, compared to a typical human hair of 100,000 nanometers), you can boost its energy production by 100 percent. And the technology could power not just phones, but a whole range of low-power mobile devices and sensors. The breakthrough is an example of 'energy harvesting' that can convert one kind of energy, such as vibrations or solar rays, into electricity."
Isn't this fairly common already (Score:5, Funny)
Re:Isn't this fairly common already (Score:5, Funny)
I see you've met my sister. She comes through clear as a bell from 8 states away. Next time, I'll have her turn her phone on...
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You're telling me that I could power the sound system with ONE WATT, and duplicate the sound energy of the auditorium that has 1000 people in it?
I need a little more info to see how that would be possible...
Granted, I'm betting that there is something interesting that happens to the piezoelectric
Re:Isn't this fairly common already (Score:5, Funny)
If she's that loud, her vocalizations could probably power other "battery operated" devices she may use...
If you can get the power down (Score:5, Insightful)
Current cell phone technology is perhaps four orders of magnitude away from piezo power. At ten times the piezo power level, say 10mW, you may as well use small cheap batteries. One non-rechargable AAA cell would run for approx 700-800 hours at those levels.
Re:If you can get the power down (Score:5, Informative)
?
Your math. It is very wrong.
A typical AAA battery is 1.5v @ about 900 mAH.
Round that up and you get 1500 mWH.
1500 mWH / 10 mW = 150 hours.
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No, his point was that the power required for a cell phone is orders of magnitude (4, according to him) higher than what you can get out of piezo electric funstuffs.
He then assumed an amazing case scenario of a cell phone needing 10 mW. He said at that power level (draw), you may as well use small cheap batteries.
He then said a single AAA would run for about 700-800 hours (at that power draw).
Given that a typical rechargeable AAA is 1.2v @ 800 mAH, it's a fair high-end estimate to say that a standard AAA (
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I don't talk enough on the phone to power it for standby. But what about one powered by motion, much like an automatic watch? Does it generate enough power?
I personally hate batteries, at least the current technology. Perhaps ultra-capacitors one day...
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I don't look forward to the contract attached to the carrier subsidy for a Rolex phone... though I still like the idea.
No battery required (Score:5, Funny)
If you assume normal human speech is about 60dB. We know dB = 10 log(I/I0) where I0 is 10^-12 W/m^2. So 60dB works out to about 10^-6 W/m^2 -- that's a microwatt per square meter. With 100% efficiency and a mike of 1 cm^2 collecting area, that's around 10^-10 W -- 0.1 nano-watts. (Thanks phliar [slashdot.org] for the calculations.)
Then utilize this energy using recent advances in String Theory, and you have a workable solution.
Here's a picture of a prototype. [worldofstock.com]
Re:If you can get the power down (Score:5, Interesting)
Because I rarely talk on my phone more than 10 minutes during the course of a month. And I still like to be able to receive calls on a random basis. Voice powered calling is worthless for people that spend that kind of time carrying the phone around rather than talking on it.
A much better solution would be to put something in that converts the jostling motion that handhelds are constantly subjected to into power. Sort of like the old self winding watches.
Re: Not Talking (Score:2)
Who said you had to talk?
Just set it next to your speakers when you crank your music up loud.
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Traffic noises are helpful now! (Score:5, Funny)
Hey, my phone's running low on power, let me find some heavy traffic and big trucks so it'll be loud enough for me to hear you!"
Next thing you know you'll have to shake your phone to get features to work (oh, wait...)
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Phone... shaking...? For... features...? Is that what they call it nowadays? ;)
Re:Isn't this fairly common already (Score:5, Insightful)
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Insightful is the standard replacement for the Funny mod. Funny doesn't give karma, but Insightful does, so Funny posts are often modded Insightful by generous mods.
Great. The guy gets useless karma, but his post invites unnecessary rebuttals.
Re:Isn't this fairly common already (Score:5, Insightful)
Talk to CmdrTaco. Of course, it's been this way for about 8 years, so don't expect anything to change. Of course, that doesn't stop them from the Web 2.0 paradigm of replacing a perfectly usable and nice home page design with something eye-gougingly ugly and much harder to use.
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What? That Slashdot gets funnier? $deity forbid!
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I just think the users' insistence on rewarding funny's with karma has unwanted consequences.
Hmm, what sort of consequences? I can't think of any except for from some metamodder who is being far too strict for anybody's good.
Re:Isn't this fairly common already (Score:4, Interesting)
Hmm, what sort of consequences?
Moderations often affect the tone of a message. A misplaced 'Insightful' mod can turn a joke into perceived ignorance. That can lead to negative moderations and a flood of comments trying to dispute it. It's not the most common thing in the world, but I've seen it happen several times.
That's not to say I'm against the idea of a funny comment being modded informative. I do, however, have a preference that people don't use Insightful mods solely to give funny comments karma. And yes, I've softened my stance a bit. Heh.
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I've also seen comments that were probably intended as serious, but the "Funny" mod turned them into a joke.
Re:Isn't this fairly common already (Score:5, Insightful)
The reason funny gets modded insightful is because negative mods hurt karma, but funny doesn't add karma. Funny can draw just as much rebuttal as insightful. So if someone says something witty that holds an issue to the light of reason I'll go for the insightful mod.
Sometimes I'll mod something I regard as particularly dense as funny rather than a negative mod. But I laugh at stupid stuff in RL too.
If you don't agree, metamod.
Re:Isn't this fairly common already (Score:5, Insightful)
On the other hand, "funny" can now be used as the mod you give to "epic fail" posts (e.g. dead wrong or missed the joke). It can raise those posts up above the trolls for all to see, and open the authors to public embarrassment, all the while failing to reward them with karma. It's really not an unfair use of the moderation system. Who said funny has to mean laughing with the author - can't it mean laughing at the author?
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Somebody who's obviously been within a couple of blocks of a standard cell phone user.
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The worst thing is that these people are also damaging the hearing of the person on the other end. Cell phones don't pipe your own voice back at you the way that landlines do. They don't do it because it's not energy efficient and would definitely cause a reduction in talktime. The reality is that a decent phone can pick up what you're saying whether or not you can.
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Doesn't the average Harley Davidson meet this description? :)
a return to Pyramid Power (Score:5, Funny)
Just set it in a Pyramid and use pyramid power to keep it topped off. That is what they ancient Egyptians did.
Don't forget to call your Mummy.
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No man, you need to put it in a cube! A cube has like, six pyramids worth of power!
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Yeah, but they're only good for powering simultaneous harmonic time machines.
not enough energy to power a modern cell phone (Score:5, Insightful)
Most modern phones are probably much too power hungry to be get enough energy from audio vibrations, even you manage to ramp up the efficiency close to 100%, which is unlikely to ever be practical.
Where this could be useful is in specialized low-power devices that get bundled into emergency survival [ready.gov]
kits.
OTOH, future cellular devices might incorporate enough improvements into power efficiency (e.g., e-ink displays [wikipedia.org]), such that you could significantly extend battery life and perhaps even power a very basic subset of the phone when the battery runs out.
Also, harnessing vibrations efficiently might be very useful in surgically implanted medical devices where replacing the battery can be rather inconvenient [wikipedia.org].
Re:not enough energy to power a modern cell phone (Score:5, Funny)
Mmmm, I dunno. If this turns out to be true my wife could talk on the phone enough to power the whole grid.
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That is a great Idea! Then you will also be burning more energy just like in a workout! You could be just exercising by sitting there!
Re:not enough energy to power a modern cell phone (Score:5, Funny)
His heart implant is failing hand me a vibrator stat!
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Yeah, but maybe, in the future, they might find that the convenience of never having to charge your phone is worth more than having the ability to watch TV/videos, browse the web, listen to music, get directions on a map, download ringtones, take pictures, and purchase all kinds of other pointless stuff to do on your phone. We're in a recession afterall, priorities people! Plus I imagine that such a phone would probably be ubersmall and uberlight.
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I'm pretty sure that when you have an active call going on a modern phone the radio gear is the most significant power drain especailly if you are a long way from a base station (with radio power required is roughly proportional to the square of distance).
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OTOH, future cellular devices might incorporate enough improvements into power efficiency (e.g., e-ink displays [wikipedia.org]), such that you could significantly extend battery life and perhaps even power a very basic subset of the phone when the battery runs out.
IMO, future cellular devices will probably use something based on IMOD display technology [wikipedia.org]. It has all the power benefits of e-ink, but considerably faster switching. They're also already available, albeit at pretty small sizes. There's also color versions of these IMOD displays avaliable, but they also suffer from the current size problems.
The Wikipedia article is somewhat short on the details, so the Qualcomm PR page is here [qualcomm.com]. Like I said, it's really a PR page trying to promote their solution, but the whit
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For emergency equipment, wouldn't it be easier and more effective to just put a damn hand crank on the thing? If kids in third world countries can power a laptop with a handcrank I think I can power a phone long enough to call 911.
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Where do you get that sort of service? I'm being serious, I live in a big city, but the closest cell phone tower for AT&T to where I live is several miles away. They seem content to only have 2 per the northern half of the city.
T-Mobile by contrast has something like 4 within half that distance.
That's just great. (Score:5, Funny)
Wonderful. I can just imagine being in a restaurant or an elevator with a group of people with phones all saying "Low Power - please speak louder."
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CAN YOU HEAR ME NOW!!!!!!!!!
GOOD!!! OUCH!!!! (as a fist-powered brickbat comes crashing down on his head)
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Why don't they use body heat? (Score:4, Informative)
And, no I am not talking about the Matrix...ok...it crossed my mind.
I remember there was also a digital watch that worked on body heat. I could not find that one, but I found another, non-digital. http://www.roachman.com/thermic [roachman.com] .
Re:Why don't they use body heat? (Score:5, Insightful)
Why would you want one? We have watches working off the constant motion of our body/arm/wrist/whatever. Mine takes a few days before it winds down. I think that anyone that stays immobile for that long will not be doing so great in respect of body heat, either.
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The harvesting of heat energy always depends on the temperature differential between two materials. The temperature differential between your body and ambient air is so low that it can only be used to produce very, very, very little power. It just so happens that a watch can be designed to run on very, very, very little power--way less than required by a cell phone, you know with its little transmitter and all that kind of stuff ;-)
Physics might say otherwise (Score:5, Informative)
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"Won't need batteries" may be a bit of an exageration, but even if the new tech only increases time between required charges a bit, it seems like a win to me.
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Meh, if the new tech provides an additional source of power, the phone manufacturers will simply fit batteries of lower capacity.
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I imagine the issue would be not wanting shoes that compressed significantly as you put your foot down and then had cables running up your trowsers to connect to your phone.
For those occasions when you need a few minuites of extra talktime urgently a handcrank is probablly easier (and yes you CAN buy them)
Technology not for some married men (Score:5, Funny)
Yes, honey. Ok, honey. Will do, honey.
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Ya, I was thinking the same thing. It would only work for woman to woman calls were they are able to fully duplex the conversation without pause.
I don't think you can power any think on uh-hu, yes, maybe, ok, and goodbye.
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I don't know if this would work for me, because I usually just end up listening on my phone. Yes, honey. Ok, honey. Will do, honey.
Yeah, but you could sell the excess power your wife generates to the utility.
I think women talking on cell phones will solve our future energy needs.
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I was thinking the same thing, but the phone would have to be wired for efficient power transmission...either that or it would need a big battery to store all the juice and then return it once it's plugged in to the grid.
Texas (Score:3, Funny)
However Olivetti is working on a cellphone powered like a self-winding watch, by arm-motion.
Supply energy to the world! (Score:5, Funny)
Just hand these out to teenage girls and we'll have enough power to supply the entire world for all its needs.
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Nah, for that you need a tiny dynamo underneath each button...
Re:Supply energy to the world! (Score:5, Funny)
Nah, for that you need a tiny dynamo underneath each button...
Bad girls have that under their zipper.
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Just hand these out to teenage girls and we'll have enough power to supply the entire world for all its needs.
gt W d tyms! tlkN OTP S so lst wk. It's ll bout txt msgN now.
Translation: Get with the times! Talking on the phone is so last week. It's all about text messaging now.
One HUNDRED Per Cent?? (Score:4, Insightful)
Wow, that is amazing!!!
Now if someone could tell me what the baseline of this increase is, we might actually learn something...
(seriously, does anyone know what the efficiency of current nano-piezoelectric power generators are?)
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Well isn't it obvious? The baseline is about half of the efficiency of these new devices.
Try to pay attention next time.
bspower (Score:2)
New idea, meet old idea? (Score:3, Interesting)
Yet for some reason we don't all have those...
Of course, very few people do much typing on their laptops now, but there are some people who presumably could have found it quite useful.
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Might you be referring to the joke that went around about 15 years ago (at least that's when I heard it) for keystroke powered word processor. It goes on to extol the virtues of such a machine, providing direct output onto paper, and using only the power of your fingers to run the entire operation. It is, of course, the venerable manual typewriter. I googled but couldn't find the old text of the "Advertisement".
Music! (Score:2)
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Just hold one of the headphones up to it once in a while.
I'm not yelling.... (Score:4, Funny)
...I'm just charging my batteries.
"battery's almost dying, I need to talk some more, let me call AOL and try to cancel."
What are they "powering"? (Score:2)
The mW needed to transmit the cell signal? Or the power needed to illuminate the 2x2" full color screen with real-time GPS positioning, speakerphone, and fluid game play?
The former.. possible. The latter.. only if you put the phone in a paint mixer.
Won't they still need batteries? (Score:2, Insightful)
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it's still going to need some sort of power source to be running when you're not talking into it.
Depends. If the user is like my girlfriend it will never be on unless her mouth is running anyway.
Bullshit (Score:2, Insightful)
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Doesn't much matter. Sound carries *extremely* low power, until you get up into frequencies far, far beyond what people can produce (with their mouths, anyway. Give me a bean burrito, and I might produce watts at 400 kHz).
Uh oh. Piezo-electric butterflies? (Score:2)
Now every phone conversation can start a tornado or hurricane somewhere!
Vibrations == Energy???? (Score:2)
I'm filing my patent for my newly invented perpetual motion device.... in a dildo.
I think I'll call it the "Infinibrator"
Do the math, Barbie (Score:5, Insightful)
It does not matter if they improve the microphone efficiency to exactly 100% The amount of power in any reasonable voice is miniscule at best. And most of the power is in the lower part of the register, where the sound wavelengths are several meters long. And to get even a fraction of the power out of a wave, you need a microphone at least a quarter wavelength across.
So even if cell phone microphones were a foot in diameter, they'd only capture a few milliwatts on voice peaks. And cell phones need a couple watts of power full-time to output a watt or so to the antenna. No way, Jose, and by at least three zeros after the "1".
Re:Do the math, Barbie (Score:5, Informative)
A little help for those too lazy to do the math:
Power per area transmitted by a sound wave:
F = p^2 / (rho0 c)
where
p = rms pressure variations in the sound wave (.01-.05 Pa or so for human voice)
rho0 = density of air (1.3 kg/m3 typ.)
c = speed of sound in air (330 m/s)
I get 1 microwatt per square meter. So for a 20-cm2 cell phone, 2 nanowatts, ignoring the receiver-coupling issues mentioned by the parent post.
No way, Jose, and by at least three zeros after the "1".
Let's make that nine.
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thanks. As a real-world example an old crystal microphone could put out one volt peak-to-peak into one megohm if you talked close. So that's about .3 volts rms, p = e^2/r or 10^-7 watts.
So I get 100 nanowatts, close enough.
You'd get 100 x more power from a one square cm solar cell, even from moonlight.
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The whole thing makes me sceptical. Especially the author's personal notes he injects, like this gem:
Wang noted that millions of these fiber pairs, each about one centimeter long, would be have to be woven into about 9 square feet of fabric (which would make for a shirt the size of really big poncho)to power an iPod.
9 square feet is a really big poncho? That's a 3x3' square. Most adult sized rain ponchos are well over 3'. Here's one that comes in at 45x53" (over 16.5 square feet) and only covers to waist to elbo. 9 square feet is probably a lot closer to XL T-shirt size than it is poncho size.
If the guy has issues comprehending something as simple as the size of 9 square feet, how can we trust him with the more complex
Our energy shortage is over! (Score:2)
Some numbers (Score:2)
A little googling found that: a cell phone requires something on the order of 1W (while in use). Speaking in a normal voice produces on the order of 0.00001W of sound energy. I don't think cell phone power requirements could ever get that low (unless the cell towers were much closer together). Interesting idea, though.
I feel a great disturbance in the force (Score:5, Funny)
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As if millions of cellphone users cried out "bullshit!" and were suddenly silenced.
Look, it's not difficult to understand: the talk-powered phone does not require batteries. However, the thing you use to charge it with does.
Talk powered? (Score:2)
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yeah, if you force my law to use this technology as an implant in all teenage girls, you can basically eliminate the need for coal/fossil fuel/nuclear fuel/etc in power plans of north america as a whole.
That would be awesome.
Not enough energy (Score:4, Insightful)
Some back-of-the-envelope calculations: normal human speech is about 60dB. We know dB = 10 log(I/I0) where I0 is 10^-12 W/m^2. So 60dB works out to about 10^-6 W/m^2 -- that's a microwatt per square meter. With 100% efficiency and a mike of 1 cm^2 collecting area, that's around 10^-10 W -- 0.1 nano-watts.
Color me skeptical.
Other vibrations (Score:2)
I wonder if it'd work for other vibrations like those incurred while pushing keys to text. "Must Twitter faster... phone's dying!"
More details + working prototype ! (Score:2)
My id is a killing word (Score:2)
R U Listening? (Score:2)
This technology wouldn't work for me.
99% of my calls are from girlfriends who only want me to listen to them go on for hours about their problems. I never get a chance to say anything.
Not LOUDER! (Score:2)
Oh, great, so then we'll have to listen to idiots not only talking LOUDER but screaming into their cellphones in public places... or in offices with bad reception....
mark
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YEAH NO I AM AT THE MOVIES WHAT? NO, WE'RE IN THAT NEW FILM, YEAH IT'S GREAT (really shouting) HANG ON I CAN BARELY HEAR YOU YEAH THE GUY DIES AT THE END I'VE SEEN IT
please god no
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These could be wall panel in loud factories and make the electric meters run slower....someday, maybe even backwards...wait....that darn 2nd law of Thermodynamics, again! Okay, slower.
I'm sure you could come up with noise sources that don't draw from the grid to get the meter to run backwards without violating entropy. It all depends on not keeping the system closed.
One way would be to regularly feed humans to the machinery. They don't consume power off of your grid, but they sure do make a lot of noise, especially when inserted feet first.
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by typing on it?
No, by blowing heavily into a tube to run the generator. This has the added benefit of operating a built-in breathalyzer, to help prevent drunk typing.
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Behold, a new unit of power: Naggawatt
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We could power entire metropolises with my mother in law.