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Turning Heat Into Sound Into Electricity

ScuttleMonkey posted more than 6 years ago | from the sounds-like-a-hot-idea dept.

Power 257

WrongSizeGlass writes "Science Daily is reporting on work by physicists at the University of Utah who have developed small devices that turn heat into sound and then into electricity. 'We are converting waste heat to electricity in an efficient, simple way by using sound [...] It is a new source of renewable energy from waste heat.' They report that technology holds promise for changing waste heat into electricity, harnessing solar energy and cooling computers and radars."

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257 comments

First post!! (-1, Offtopic)

ShadowXOmega (808299) | more than 6 years ago | (#19384271)

My first, first post!

=D

wow, now thaw gives a new meaning for "power metal"

Re:First post!! (0)

Anonymous Coward | more than 6 years ago | (#19384351)

Took it away from the shock site troll...

I win (-1)

Anonymous Coward | more than 6 years ago | (#19384277)

I got the first post!

Linux Toaster? (0, Offtopic)

Maliron (1026708) | more than 6 years ago | (#19384287)

This new technology should bring us one step closer to the uber efficient linux toaster! "Anyone want more bread? I need more power to finish this compile!"

"University" of Utah (-1, Troll)

Anonymous Coward | more than 6 years ago | (#19384305)

Lol, Mormon science. Doesn't the Lord frown upon this kind of science?

"convert heat into electricity has to key steps" (0)

Anonymous Coward | more than 6 years ago | (#19384321)

Gee. I wonder what they are.

But.... (5, Funny)

a.phoenicis (1026040) | more than 6 years ago | (#19384345)

But does it change waste heat into electricity? I'm not quite sure based on that write-up...

Sound to electricity. (5, Funny)

snowraver1 (1052510) | more than 6 years ago | (#19384355)

Now they need to refine this to 100% effiecency and attach one to my wife.

Re:Sound to electricity. (2, Funny)

Simply Curious (1002051) | more than 6 years ago | (#19384571)

On the other hand, any inefficiency would show up as heat, allowing it to cycle through towards absolute zero.

Wait a minute...

Ack! Stupid Second Law of Thermodynamics.

YOU NEVER LISTEN TO ME! (0)

Anonymous Coward | more than 6 years ago | (#19384807)

/love you dear.

Heat to Sound to electricity. (5, Funny)

malvidin (951569) | more than 6 years ago | (#19384825)

Well, luckily my wife doesn't need to be loud. She's that hot.

Re:Heat to Sound to electricity. (0)

Anonymous Coward | more than 6 years ago | (#19384911)

SWEET

Re:Sound to electricity. (0)

Anonymous Coward | more than 6 years ago | (#19384993)

Funny, over on myhusbandisageek.com she said the exact same thing about you. The highest rated comment was how you'd take it apart and electrocute yourself.

Sound, you say... (1)

NeoTerra (986979) | more than 6 years ago | (#19384357)

Why bother turning the sound to electricity? Then I could just load up some music to the car, and play the sound as the engine warms up :) I suppose that's why it's not getting put into cars :)

Efficiency as opposed to thermoelectric? (5, Interesting)

Anonymous Coward | more than 6 years ago | (#19384359)

I just skimmed the article, but I didn't see mention of the efficiency of this process. What are the advantages to converting the heat to sound first, rather than directly to electricity via thermoelectric processes?

Re:Efficiency as opposed to thermoelectric? (1)

hwyengr (839340) | more than 6 years ago | (#19384569)

Is the efficiency really that important? The heat they're using was 100% wasted in the first place.

Re:Efficiency as opposed to thermoelectric? (4, Funny)

cosinezero (833532) | more than 6 years ago | (#19384727)

And from the looks of that giant glass pipe lit by a blowtorch, my money's on the researchers being 100% Wasted while thinking this one up, too.

Re:Efficiency as opposed to thermoelectric? (1)

oskay (932940) | more than 6 years ago | (#19384711)

On the other hand, thermoelectric devices with significant capacity are pretty expensive. This might be a much less expensive route to the same goal.

(On the third hand, this is military funded research, so I'd be a little bit surprised if that were the make-or-break feature.)

Re:Efficiency as opposed to thermoelectric? (2, Insightful)

LWATCDR (28044) | more than 6 years ago | (#19384761)

I think cost is more important the efficiency. If it was cheap enough and if you could say get 10% out of it it could be very useful.
Imagine replacing a car radiator with it?

Re:Efficiency as opposed to thermoelectric? (3, Informative)

dch24 (904899) | more than 6 years ago | (#19384833)

You want to read the Original Article [utah.edu] . Although the link above is almost an exact copy, there's some interesting stuff at the bottom of the original:

Physicist Orest Symko's graduate students will present their studies during an Acoustical Society of America technical session from 8 a.m. to 10:05 a.m. MDT Friday, June 8 in Parlor B of the Hilton Salt Lake City Center hotel, 255 S. West Temple.
It would be interesting to hear all the questions there. I imagine yours will be handled pretty well.

Obviously the conversion to sound can't beat Carnot's Theorem [wikipedia.org] , and it says in the article it doesn't start until there's a temperature gradient of at least 90 degrees F. In other words, it's not very efficient.

Re:Efficiency as opposed to thermoelectric? (1)

weszz (710261) | more than 6 years ago | (#19385079)

Once the second student stepped in, then it got better... the air pressure is the key... until you puncture it and it blows up...

She built cylindrical devices 1.5 inches long and a half-inch wide, and worked to improve how much heat was converted to sound rather than escaping. As little as a 90-degree Fahrenheit temperature difference between hot and cold heat exchangers produced sound. Some devices produced sound at 135 decibels -- as loud as a jackhammer.

-- Student Nick Webb showed that by pressurizing the air in a similar-sized resonator, it was able to produce more sound, and thus more electricity.

He also showed that by increasing air pressure, a smaller temperature difference between heat exchangers is needed for heat to begin converting into sound. That makes it practical to use the acoustic devices to cool laptop computers and other electronics that emit relatively small amounts of waste heat, Symko says.

Woot (-1, Redundant)

Anonymous Coward | more than 6 years ago | (#19384363)

Just think of all those screaming monkeys.

1. Do not feed monkeys for 10 days
2. Swing bananas from the ceiling where the monkeys reside
3. ???
4. Profit.

Can it really be this good? (3, Interesting)

Nom du Keyboard (633989) | more than 6 years ago | (#19384381)

This would seem to say that I can take waste heat from my A/C heat-exchangers making them more efficient, and create electricity to drive said system and fans in the process. Given that it's about 100 degrees outside at this moment, this would be sweet!

Re:Can it really be this good? (2, Informative)

Lumpy (12016) | more than 6 years ago | (#19385111)

you need a significant heat differential as well as the fact that AC needs fast dissipation to work.

Ac coils need to shed that heat fast, even faster when the ambient temperature is up there like 100degF (I hope you mean 100F and not 100C) This process relies on a wider temperature differential and not shedding it fast.

so it will not work in most places where waste heat energy recovery would be a benefit.

Re:Can it really be this good? (2, Interesting)

Steendor (917855) | more than 6 years ago | (#19385251)

Maybe it wouldn't work very well in the A/C, but I bet it could be used externally. For a while, my parents had a large thru-wall unit exhausting into an enclosed space, and that space got very warm.

dude (0)

Anonymous Coward | more than 6 years ago | (#19384383)

this sounds hot.

yeah, its monday, im retarded.

Massive /. potential (4, Funny)

u-bend (1095729) | more than 6 years ago | (#19384405)

There's so much waste heat here (Star Wars, Linux, browser, KDE/Gnome debates), that we could power a city and rock out at the same time.

Re:Massive /. potential (0, Offtopic)

u-bend (1095729) | more than 6 years ago | (#19384671)

Heh, you think that's funny? How come my 'funny' posts always start off life as 'Interesting?' I mean, sure, I actually have the secret formula for deriving energy from /. flame-wars. Why yes, that is indeed interesting!

Re:Massive /. potential (0, Offtopic)

u-bend (1095729) | more than 6 years ago | (#19384707)

OMG, now it's 'Insightful' after a brief stint at 'Funny!' This is cracking me up. OK, back to work.

No efficiency ratings (4, Insightful)

denis-The-menace (471988) | more than 6 years ago | (#19384419)

How efficient is it?

With double conversions it couldn't be much.

Why not convert heat into electricity DIRECTLY using a peltier device?
(aka Seebeck effect http://en.wikipedia.org/wiki/Thermoelectric_effect [wikipedia.org] )

Re:No efficiency ratings (4, Insightful)

drinkypoo (153816) | more than 6 years ago | (#19384589)

Why not convert heat into electricity DIRECTLY using a peltier device?

Because peltier junctions are themselves horribly inefficient?

Re:No efficiency ratings (1)

JavaBrain (920722) | more than 6 years ago | (#19385027)

that only works for temperature deltas

Re:No efficiency ratings (0)

Anonymous Coward | more than 6 years ago | (#19385303)

So does this - as stated in the article and any introductory thermodynamics text. You can't do any work without a temperature delta.

Re:No efficiency ratings (1)

TheSkyIsPurple (901118) | more than 6 years ago | (#19385307)

but if the device is giving off 150F heat, and ambient temperature is 90F, doesn't that give a temperature delta?

Re:No efficiency ratings (1)

CastrTroy (595695) | more than 6 years ago | (#19385143)

Well theoritically, this could be better. If the efficiency of converting from heat to sound was 80%, and the efficiency of converting from sound to electricity was 80%, then it would be more efficient than a thermoelectric device that was only %50 efficient. It doesn't matter how many processes you go through, it's how efficient those processes are. For instance, you can use solar panels to create electricity. And some have an efficiency of somewhere around %5. Now you could also use Coal power to create Hydrogen from water, and use hydrogen to generate electricity, and you'd end up way more efficient than many solar panels.

Re:No efficiency ratings (0)

Anonymous Coward | more than 6 years ago | (#19385427)

We're already doing that, Coppertop. Go back to sleep, have a steak.

I wonder (2, Interesting)

Normal Dan (1053064) | more than 6 years ago | (#19384421)

If it could be used to practically and economically extract the rest of the energy from nuclear waste, which still produces quite a bit of heat. 'Free' power for thousands of years.

does it have to (1)

c0ld4usion (1111281) | more than 6 years ago | (#19384425)

...come from Utah?

I have not RTFA, but a heat gradient is usually required for these devices. If you have a heat gradient, use a thermocouple.

Maxwell's Daemon Rides Again? (5, Informative)

overshoot (39700) | more than 6 years ago | (#19384441)

Unless they're claiming to have found a way around the Second Law, the efficiency of any such conversion is going to utterly suck. My CPUs run less than 10C above ambient, so the absolute Carnot limit on any converter recovering that heat is going to be about 3%.

Why bother?

[1] Thermodynamics, not Robotics

But this is from Utah (0, Troll)

shis-ka-bob (595298) | more than 6 years ago | (#19384549)

In the land of Cold Fusion, normal laws of physics don't seem to apply. This is only a problem when the rest of us try to replicate the results without access to divine intervention (e.g. from locations out of line of site of the Mormon Tabernacle)

Re:But this is from Utah (0)

Anonymous Coward | more than 6 years ago | (#19384709)

Nice bigot blast. BTW University of Utah isn't the Mormon school. That is where a lot of the people that don't like the Mormon Church go. BYU and Utah State are the heavily Mormon schools. Now U of U is the school of cold fusion fame but that has nothing to do with the Mormon Church.

Re:But this is from Utah (1)

CodeShark (17400) | more than 6 years ago | (#19384895)

Yabut...

I'm out of line of sight from Utah. Using a CRT based device. Transmits electrons using Wifi. Can do pictures. Even tunable video streams at set frequencies...

Ever hear of television? Invented in Utah -- see Philo Farnsworth in Wikipedia if you don't believe me.

So your statement about Mormon anything is nothing more than a bit of religious flamebait...

Re:But this is from Utah (1)

malvidin (951569) | more than 6 years ago | (#19384939)

The room that Pons (of Pons and Fleishman Cold Fusion fame) work in was far from the line of sight of anything. It was in the basement of the University of Utah chemistry building. The engineering building this research was done at is at least a half mile away.

Yes, I know you were joking, but Fleishman wasn't from Utah.

Re:Maxwell's Daemon Rides Again? (1)

swilver (617741) | more than 6 years ago | (#19384741)

Your CPU's run at less than 10C above ambient because it has a huge cooler sitting on top -- the CPU may be cool, but only bacause a lot of heat is extracted from it and pumped out of the system.

Re:Maxwell's Daemon Rides Again? (1)

overshoot (39700) | more than 6 years ago | (#19384907)

Your CPU's run at less than 10C above ambient because it has a huge cooler sitting on top -- the CPU may be cool, but only bacause a lot of heat is extracted from it and pumped out of the system.
That's kind of the idea, no?

I'm really not interested in running my CPU at 100C so that the heat recovery efficiency goes from 3% to 19%, thank you.

Re:Maxwell's Daemon Rides Again? (2, Informative)

byron036 (178130) | more than 6 years ago | (#19384999)

If the device extracts energy, then the temperature of your CPU will be lowered. Thus replacing the heatsink.

Re:Maxwell's Daemon Rides Again? (1)

spun (1352) | more than 6 years ago | (#19385017)

Yes, but you don't measure the heat difference AFTER the heat has been removed! The Carnot efficiency depends on the heat differential BEFORE the heat has been pumped, yes?

Re:Maxwell's Daemon Rides Again? (1)

overshoot (39700) | more than 6 years ago | (#19385315)

Yes, but you don't measure the heat difference AFTER the heat has been removed! The Carnot efficiency depends on the heat differential BEFORE the heat has been pumped, yes?
You measure the heat difference between the hot side and the cold side of the transfer. In the case of a CPU, between the CPU and ambient.

For more, you really need to understand the Second Law of Thermodynamics and Carnot engines. [wikipedia.org]

Re:Maxwell's Daemon Rides Again? (1)

indros13 (531405) | more than 6 years ago | (#19384759)

Even if the efficiency is low, it still might pay off to potentially eliminate the need for a fan, no? Your point is well taken, however. This isn't going to save us from our fossil fuel overlords, merely help reduce power use (or increase generation) on the margins.

Depends how you define waste (1)

Colin Smith (2679) | more than 6 years ago | (#19385097)

I believe the key point about the device is the lack of moving parts. A steam turbine for instance has a shit load of highly expensive moving parts to make it work.

 

Depends how much it costs. (0)

Anonymous Coward | more than 6 years ago | (#19385199)

It depends how much it costs. If the cost of implementing and using it is low enough, it doesn't matter if the efficiency is low. This is waste heat that is currently being completely discarded.

Good for comps (3, Insightful)

eebra82 (907996) | more than 6 years ago | (#19384457)

I realize this could be a great thing for computers - especially portable computers. However, I am more interested in how large portion of the heat that turns into sound and eventually into electricity. My stationary computer is fine without all that extra power. What I want is to know if this will kill the need for huge fans and actually remove some of the heat, or if it will just suck a small portion of it.

Use in autos? (3, Funny)

evildarkdeathclicheo (978593) | more than 6 years ago | (#19384467)

Since the internal combustion engine is really a noisy heat pump, wouldn't this be of use in hybrids, or perhaps as an alternative alternator? (alternatator? alternatatoe?) Perhaps in the cubicle farms of tomorrow, we'll all be sitting on these heat-powered piezo tubes and fed a diet of beans to power our own workstations.

to heck with "waste" heat... (1)

dAzED1 (33635) | more than 6 years ago | (#19384529)

if they can actually do this, then set up massive arrays of it on top of active volcanoes and other natural heat sources. As the claim is they end up with electricity, that means there is less heat, and we have this maybe/maybe not global warming thing going on. Seems we can reduce a lot of the natural warming of the earth's atmosphere with something that can do this, if it really can...

Re:to heck with "waste" heat... (2, Funny)

woolio (927141) | more than 6 years ago | (#19385283)

if they can actually do this, then set up massive arrays of it on top of active volcanoes and other natural heat sources. As the claim is they end up with electricity, that means there is less heat, and we have this maybe/maybe not global warming thing going on. Seems we can reduce a lot of the natural warming of the earth's atmosphere with something that can do this, if it really can...

Yes, but can you imagine the environmental effects caused by cooling a volcano at "Faster-Than-Nature-Indended" rate?

The environmentalists would raise hell!

Dog Whistle (4, Funny)

Apocalypse111 (597674) | more than 6 years ago | (#19384535)

Symko says the devices won't create noise pollution. First, as smaller devices are developed, they will convert heat to ultrasonic frequencies people cannot hear.
So now we've turned my car into a mobile dog-whistle, causing even the well-behaved dogs to bark at me.

Ooh, on the other hand, maybe we could get the sound into the frequency range at which various crystal wine glasses shatter... I've got some asshole neighbors who could do without those particular bits of glasswear.

Re:Dog Whistle (0)

Anonymous Coward | more than 6 years ago | (#19384627)

"Bits of glasswear"... sounds painful.

Diaphragms? (4, Interesting)

bigattichouse (527527) | more than 6 years ago | (#19384537)

would it be possible to do something with a speaker? (as an experiment). I understand TFA about the piezeo devices being compressed/released by the plates vibrating like a flute, but I started wondering about the image that immediately popped into my head, of tuned diaphragms responding to air pressure differences to vibrate a coil... I guess if you did the flute thing, you could just put a piezo crystal between a tuning fork and a solid surface... every note at that frequency, especially if sustained, would then make power.... So, how about making great huge "moaning towers" out in the middle of nowhere that do the same thing? I'll call it "BULLROAR"(tm) technology. Hell.. I wonder if the forces involved on a bullroar spinning aroud your head might generate power (say, with a couterweight like thos rechargable watches). This idea is kinda fun.

Rube Goldberg Rejoice !! (1)

Timtimes (730036) | more than 6 years ago | (#19384551)

Why not add a few other links in the conversion process just to sound even sexier? Efficiency is so pre 9-11. Enjoy.

It's a Vicious Cycle! (1)

mandark1967 (630856) | more than 6 years ago | (#19384573)

Waste heat converted into sound and then converted into electricity which, when used, creates more waste heat which has to be converted into sound and then electricity, which creates yet more waste heat that has to be converted into sound then back into electricity... When will the madness stop?!?!?!?!

cooling computers? (2, Insightful)

gEvil (beta) (945888) | more than 6 years ago | (#19384581)

I'm not sure about you, but when I spec parts for computer cooling, I'm looking for something that's cool AND quiet. I don't want whatever device to be creating extra sound in it's quest to cool more efficiently.

Finally! (0)

Anonymous Coward | more than 6 years ago | (#19384601)

We might finally get an answer to the age-old question:

"if a tree falls in the forest and nobody is there to hear it, does it make any noise?"

just hook this thing up to a little device that can text you once it's running.

use it to power my computer (0)

Anonymous Coward | more than 6 years ago | (#19384629)

It could be connected to the heat sink on the CPU, hard disk, and on the LCD backlight. The resultant energy could be fed back to the computer to recover the lost energy reducing energy consumption. If it could be made to be 100% efficient, the laptop could work forever on a single charge! Of course it could also draw energy from the lap on which the laptop is sitting (correlation in heat versus sites visited).

Wait, I didn't post that... oops.

Please see my patent for "A Method of Recovering Waste Energy and Extending the RunTime of Electronic Equipment".

Also the patent for "A Method of Continuously Powering a Computer Laptop from Waste Heat".

Re:use it to power my computer (2, Interesting)

ThosLives (686517) | more than 6 years ago | (#19384845)

I've always wanted to try using the thermal dissipation of the processor to power its own cooling system. That is, create a pressurized case, and have an intake compressor that brings in cool air, which is heated by the processor(s), which is then sent out through a power-tapping device (turbine or piston) to power the compressor and keep things going.

Basically a Brayton-cycle cooling system. You could actually move a lot of air with 300W power dissipation! (way more than you can with a little 15 W cooling fan).

(Too bad the drawbacks are that it requires some pretty slick machinery and a pressure chamber :p )

Interesting but low on power production? (1)

CodeShark (17400) | more than 6 years ago | (#19384677)

AFAICT the "power" production is related to the fact that they have created a way to get vibration from a temperature rise at a given "resonant" frequency in a tube. Cool but there still has to be a heat rise -- and the power out is limited by the Carnot law to 1-(Temp Low/Temp High) in absolute temp units. So with a 90 degree fahrenheit heat rise, for example, the maximum efficiency (using room temp as t low) of about 14% -- the actual output is probably lower. Or about the same as current generation not-very-expensive thin film PhotoVoltaic cells.

So as a solar source these devices are most likely a bust -- I just don't see a tube + device + piezo type of setup beating the think film. Leaving a question for the researchers -- how many devices over what area would be required to utilize these as a bottoming cycle for a small power plant?

Re:Interesting but low on power production? (1)

Overzeetop (214511) | more than 6 years ago | (#19385267)

Don't necessarily discount solar sources. Solar can produce quite a bit of heat, and being able to produce power from a 500-700F element could feasibly produce 30-40% efficient devices if the acoustic conversion is highly efficient. One poster mentioned poor output, with high voltages and small current, but a parallel set of such devices might deliver a net current that is into the useful range. Even 30% of 1200W/m is a nice return. I suppose it depends on the longevity of the components at higher temps and the cost to manufacture as to whether the net value is enough to make it commercially viable.

I know that solar farms have been built with a central heated tower (very cool looking, if not terribly efficient and subject to large fires stirling cycle?), but this might allow a bunch of independent modules and would tend to fail gracefully, since running a larger number of units in parallel would allow for individual units to fail without taking the whole system down (I would hope).

Slow down everyone (1)

scottennis (225462) | more than 6 years ago | (#19384697)

This is from the same institution that brought you cold fusion (not the markup language) a few years back.

I'm just sayin' . . .

In Related News... (1)

DaveWick79 (939388) | more than 6 years ago | (#19384739)

Sources in Washington DC claim to have found a way to power 73% of the nation's capitol while nearly completely reducing the greenhouse emissions from the capitol building. Within a few years, planners expect this new energy source to power the entire city as well as the capacity to sell energy to surrounding areas.

Re:In Related News... (0)

Anonymous Coward | more than 6 years ago | (#19385073)

Sources in Washington DC claim to have found a way to power 73% of the nation's capitol while nearly completely reducing the greenhouse emissions from the capitol building.
Converting the hot air coming from the politicians into sound? Sounds like a perpetual motion machine. And if production gets low just add some ethanol? Can't wait for the spin on this.

World's Largest Crack Pipe (0)

Anonymous Coward | more than 6 years ago | (#19384743)

I don't know about anyone else, but the photo accompanying the linked article looks like that guy is firing up the world's largest crack pipe!
Only we can't see who's toking on it.

Skunky

Cooling (1)

malvidin (951569) | more than 6 years ago | (#19384751)

I remember visiting a friend there who was working on this project. He mentioned that they were using tuned sound to cool devices. The inverse is what they are talking about here. Going either way there will be losses, but without looking at the data I can't make any observations about efficiency. I guess I could call and ask for more info...

Less heat is good... (2, Funny)

FlyByPC (841016) | more than 6 years ago | (#19384793)

...as long as the sound-conversion part doesn't leak too much. My workstation already sounds like a jet engine.

amount of electricity per heat unit? (1)

192939495969798999 (58312) | more than 6 years ago | (#19384859)

It doesn't indicate what amounts of electricity could be retrieved, from what I read, but it almost wouldn't matter if it was cheap enough to build. You could blanket death valley with these things, and at least on summer days generate enough electricity to offset grid saturation by excess a/c units in some large area (hopefully large enough to justify the cost).

Just a little prob with the numbers.... (5, Insightful)

Ancient_Hacker (751168) | more than 6 years ago | (#19384869)

Nothing to see here. It's just a Prof that's spent $2 million on a wild goose chase. Now with the great smell of fish! The rub is multi-fold:
  • Good old Carnot's law. The efficiency is limited by the temperature drop across the device compared to the absolute temperature. Now take two thermometers, stick one up your butt and fart. compute the temperature difference. Divide by 483. That's your efficiency in converting heated gas into sound. Prolly about 0.005% as a rough approx.
  • For a less gross example, pucker your lips and blow. Do this for five minutes or until you pass out. You probably feel warm-- that's the heat. How much acoustic power did you generate? Well a loud whistle is about 100dbA, about a hundredth of a watt. Efficiency, 0.004% at best.
  • Piezoelectic efficiency. Well, it's really high-- for an acoustic transducer. The Interwebs seem to reveal no figures for this, and in general a high level of coyness is a way of hiding embarrasing numbers. Let's assume a best-case number of say 40%.
  • The impedances. Crystals are very high impedance devices, putting out LOTS of volts at vanishingly small amps, which is bad news for us, as most of our power sinks are low impedance. Getting a few milliamps at 40KV is not very compatible with powering your laptop, which is about a million times lower in impedance. It's particularly inconcvenient converting tens of kilovolts downwards with economy and efficiency.
So sorry, probably much less than nothing to see here, just another bundle of our taxpayer's money spent on a totally pointless technical exercise.

Global Warming (0)

Anonymous Coward | more than 6 years ago | (#19384917)

So, global warming is a boon? We now have a renewable source of energy!

so what you're saying is... (0)

Anonymous Coward | more than 6 years ago | (#19384929)

I can hook this device up to my wife's ass and use it to power a small fridge for my beer? Even though that would be nice, I would much rather they spent valuable R&D time on something the average man could use. How about a mute button for afforementioned wife? MY KINGDOM FOR VOLUME CONTROL!

Wireless power! (0)

Anonymous Coward | more than 6 years ago | (#19385093)

1) Build giant amplifiers/speakers at power plants
2) Power remote villages without difficult constructions
3) ???? Profit !!!!

Even Better (1)

Orig_Club_Soda (983823) | more than 6 years ago | (#19385291)

Figure out how to turn sound from the inner city, construction sites, and freeways in to electricity. There is so much noise pollution out there, this would be practically free.

Could you image: singing to your flashlight to keep it lit!

This is the mechanism (1, Informative)

Anonymous Coward | more than 6 years ago | (#19385411)

This IS a stirling engine. Specifically, a modification of the thermoacoustic stirling engine [americanscientist.org] originally developed at LANL.

Are these the same guys that (1)

recharged95 (782975) | more than 6 years ago | (#19385441)

did the cold fusion "breakthroughs" back in the 90's.

Man, I need to goto that school, they must be smoking some good stuff.

In the end, more heat = more energy = more heat. Entropy r0cks!

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"ecode" can be used for code snippets, for example:

<ecode>    while(1) { do_something(); } </ecode>
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