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LED's Efficiency Exceeds 100%

Soulskill posted more than 2 years ago | from the that-makes-things-easy dept.

Science 502

New submitter Paul Fernhout writes "Physicists from MIT claim to have demonstrated that an LED can emit more optical power than the electrical power it consumes. Researchers suggest this LED acts like a heat pump somehow (abstract). Is it true that 230% efficient LEDs seem to violate first law of thermodynamics?"

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No (0)

Anonymous Coward | more than 2 years ago | (#39291037)

...

Maybe (5, Informative)

MyLongNickName (822545) | more than 2 years ago | (#39291157)

"30 picowatts and measured an output of 69 picowatts of light - an efficiency of 230%. The physical mechanisms worked the same as with any LED: when excited by the applied voltage, electrons and holes have a certain probability of generating photons. The researchers didn’t try to increase this probability, as some previous research has focused on, but instead took advantage of small amounts of excess heat to emit more power than consumed. This heat arises from vibrations in the device’s atomic lattice, which occur due to entropy."

They are not claiming more than 100% efficiency in total terms.

Re:Maybe (5, Funny)

Anonymous Coward | more than 2 years ago | (#39291209)

HOLY SHIT ITS A ZPM!!!!

Re:Maybe (0)

Anonymous Coward | more than 2 years ago | (#39291349)

When, for a moment there I thought I had jumped forward in time to April first.

Re:Maybe (0)

erick99 (743982) | more than 2 years ago | (#39291433)

Good explanation. Wish I could mod you up but you'll be at 5 in a few minutes anyway.

Re:No (5, Informative)

jdgeorge (18767) | more than 2 years ago | (#39291289)

According to TFA, they are actually taking advantage of other sources of energy in addition to the electricity provided by the wall plug. So it's not really the LED getting "greater than 100% efficiency", it's really "producing more light than you would get if you only took advantage of the electricity from the wall plug".

And they're talking in the range of 69 picowatts of light output, using only 30 picowatts of "wall plug" energy input. So it's quite believable.

Re:No (4, Informative)

MightyMartian (840721) | more than 2 years ago | (#39291317)

Yes, to say 230% efficient is really a false statement. There's no violation of thermodynamics, it's just that the LED has more energy sources than the electrons it's drawing down the wire.

Re:No (4, Funny)

Surt (22457) | more than 2 years ago | (#39291507)

The fun trick will be to point this at a 45% efficient photovoltaic panel to generate the electricity.

They must have used the wrong cable (5, Funny)

s_p_oneil (795792) | more than 2 years ago | (#39291047)

They must have used the wrong cable, causing the light to go faster than C and mess with their readings.

Re:They must have used the wrong cable (4, Funny)

masternerdguy (2468142) | more than 2 years ago | (#39291095)

They could have reversed the polarity of the diode causing a 100% change in efficiency.

Re:They must have used the wrong cable (4, Funny)

jd (1658) | more than 2 years ago | (#39291141)

They could have reversed the polarity of the neutron flow, causing the LED to be coupled to the singularity driving the Time Lords' TARDISes.

Re:They must have used the wrong cable (5, Funny)

ColdWetDog (752185) | more than 2 years ago | (#39291401)

I thought you had to reverse the tachyon polarity.

Now I'm all confused.

Re:They must have used the wrong cable (0)

Anonymous Coward | more than 2 years ago | (#39291153)

Clearly faulty GPS signalling!

Re:They must have used the wrong cable (5, Funny)

royallthefourth (1564389) | more than 2 years ago | (#39291191)

Ah! Monster cables are good for something after all.

Re:They must have used the wrong cable (5, Funny)

Alter_3d (948458) | more than 2 years ago | (#39291233)

They must have used the wrong cable, causing the light to go faster than C and mess with their readings.

It was obviously a Denon AKDL1 Dedicated Link Cable [amazon.com]

Re:They must have used the wrong cable (1)

hoggoth (414195) | more than 2 years ago | (#39291331)

Here's your problem, your using Monster Cables. They are known to exceed C.

No (-1)

the eric conspiracy (20178) | more than 2 years ago | (#39291049)

It isn't true.

Re:No (5, Informative)

ChronoReverse (858838) | more than 2 years ago | (#39291075)

Exceeds 100% ELECTRICAL efficiency is the key here. The conservation of energy is still intact because it supposedly uses heat energy to supplement.

Re:No (2)

mcgrew (92797) | more than 2 years ago | (#39291275)

Thank you for that, TFS made it look like they somehow managed to overcome the laws of thermodynamics. I was going to ask you to explain farther but RTFA instead.

As the researchers explain in their study, the key to achieving a power conversion efficiency above 100%, i.e., âoeunity efficiency,â is to greatly decrease the applied voltage. According to their calculations, as the voltage is halved, the input power is decreased by a factor of 4, while the emitted light power scales linearly with voltage so that itâ(TM)s also only halved. In other words, an LEDâ(TM)s efficiency increases as its output power decreases. (The inverse of this relationship - that LED efficiency decreases as its output power increases - is one of the biggest hurdles in designing bright, efficient LED lights.)

It seems to me that it's just fiddling with the numbers; it isn'r really ">100%", it's "better than 100% when compared to higher power levels."

I did expect a better article from Psysorg. I'm still not completely clear on it, but it seems to have no practical value, only an academic excersize.

Re:No (2)

next_ghost (1868792) | more than 2 years ago | (#39291493)

I can see a practical application right off the bat - completely silent cooling for computers and satellites. As I understand, particularly the latter is a huge pain in the ass for engineers.

Re:No (2)

mws1066 (1057218) | more than 2 years ago | (#39291211)

From the article: "In their experiments, the researchers reduced the LED’s input power to just 30 picowatts and measured an output of 69 picowatts of light - an efficiency of 230%." It only would violate the conservation of energy if it converted the electricity to more electricity than came in. It's just converting the electricity into light very efficiently with a great ratio.

Re:No (1)

gcnaddict (841664) | more than 2 years ago | (#39291319)

It's just converting the electricity into light very efficiently with a great ratio

No, it's not even using the electricity to generate light for the most part. The electricity is effectively reducing the remaining threshold needed for ambient heat to be converted to light. In terms of overall energy efficiency, one would find it would still be under 100% if the amount of ambient heat lost could be measured.

Re:No (1)

networkBoy (774728) | more than 2 years ago | (#39291379)

Then that means at some level they have made a solid state heat pump that rejects the waste heat as light. /cool
-nB
*chuckles*

No. (-1, Redundant)

Chris Mattern (191822) | more than 2 years ago | (#39291073)

Either a) they've made a mistake or b) the LED is consuming itself in some fashion to produce the additional light and will eventually burn out.

Re:No. (3, Informative)

nedlohs (1335013) | more than 2 years ago | (#39291111)

Or you could read the damn links and find out. But I guess easier to make guesses.

Re:No. (4, Funny)

a_nonamiss (743253) | more than 2 years ago | (#39291413)

You must be new here...

Re:No. (4, Informative)

Dynedain (141758) | more than 2 years ago | (#39291195)

It says in the summary (and in the article) that the LED at very low electrical input levels, acts as a heat pump. It absorbs local heat energy and converts into photons.

So you get more light out than electricity in, because you're stealing heat and converting it to light. It's not more than 100% efficient, it's multiple energy sources being used. No breaking the laws of thermodynamics.

Re:No. (1)

jomegat (706411) | more than 2 years ago | (#39291261)

So if you had enough of these, you could air condition your house with them?

Re:No. (4, Insightful)

tibit (1762298) | more than 2 years ago | (#39291351)

Yeah, but man, a it's a completely solid state heat pump that dumps waste heat as usable light - now that's something. Just imagine: every server, instead of needing cooling, can have this stuck to the heatsink and mounted on a tall pole. No more datacenter, we'll have datapoles, and our streets will be full of them :)

Re:No. (0, Troll)

Anonymous Coward | more than 2 years ago | (#39291215)

Why don't you just read the fucking article? I know its slashdot and everything, and nobody reads the damn articles, etc. You could at least give a try before spouting off with your reasons why it can't be so.

Fucking idiots.

Re:No. (5, Funny)

Enderandrew (866215) | more than 2 years ago | (#39291443)

Read the article? Heck, I didn't finish the headline. As soon as I realized it didn't mention iPads I went straight to the comments to argue we should instead discuss iPads.

Why don't we have iPad 4 speculation yet?

1. I for one welcome our new iPad 4 overlords and their app that allows you to put hot grits on Natalie Portman and disguise it in a bad car analogy.
2. Ask if it runs Linux, and then cite another failed year of Linux on the desktop.
3. ???
4. Profit.

What were we talking about again?

Re:No. (3, Insightful)

gregfortune (313889) | more than 2 years ago | (#39291219)

The LED is "consuming" external heat to produce the additional light. The article is pretty clear and an enjoyable read.

Re:No. (1)

fuzzyfuzzyfungus (1223518) | more than 2 years ago | (#39291345)

A new entrant into the solid-state heat pumps field would be rather nice... I wonder if they can get this thing to scale up a bit?

Re:No. (1)

ColdWetDog (752185) | more than 2 years ago | (#39291481)

How many orders of magnitude is 'a bit' in your world?

Yes. (1)

hannson (1369413) | more than 2 years ago | (#39291367)

Had you read TFA you'd realize that it's you who's mistaken.

In their experiments, the researchers reduced the LED’s input power to just 30 picowatts and measured an output of 69 picowatts of light - an efficiency of 230%. The physical mechanisms worked the same as with any LED: when excited by the applied voltage, electrons and holes have a certain probability of generating photons. The researchers didn’t try to increase this probability, as some previous research has focused on, but instead took advantage of small amounts of excess heat to emit more power than consumed. This heat arises from vibrations in the device’s atomic lattice, which occur due to entropy.

This light-emitting process cools the LED slightly, making it operate similar to a thermoelectric cooler. Although the cooling is insufficient to provide practical cooling at room temperature, it could potentially be used for designing lights that don’t generate heat. When used as a heat pump, the device might be useful for solid-state cooling applications or even power generation.

Well, it's clear that... (0)

Anonymous Coward | more than 2 years ago | (#39291083)

either the researchers are wrong, or physics is.

Well, it's clear that... (0)

Anonymous Coward | more than 2 years ago | (#39291339)

either I didn't read the article, or I read it before posting this crap.

FTFY.

Let's go out on a limb... (0)

Anonymous Coward | more than 2 years ago | (#39291089)

... and predict that they measured something the wrong way.

Combine with a greater than 80% solar cell (0)

Anonymous Coward | more than 2 years ago | (#39291097)

BAM, free energy!!!!

Or we will freeze the earth over cause we are eating heat....

Re:Combine with a greater than 80% solar cell (4, Funny)

masternerdguy (2468142) | more than 2 years ago | (#39291251)

Global warming to the rescue!

Re:Combine with a greater than 80% solar cell (2)

mbenzi (410594) | more than 2 years ago | (#39291311)

That was my first thought. Even the explanation of the extra energy coming from heat is nice and doesn't stop solar cell from working. Might actually work well together: the cell is going to leak heat, this will soak it up.

LED Cooling (5, Informative)

DarkXale (1771414) | more than 2 years ago | (#39291099)

So if I get the article right - LED cooling?

Really puts a whole new perspective on LED clad 'gaming'-machines, which as you know - should have blue LEDs for cooling, and red LEDs for superior overclocking.

There *is* someone who can read! (3, Insightful)

DeathToBill (601486) | more than 2 years ago | (#39291177)

11 comments down and finally someone has actually understood enough of the summary to know that they aren't claiming that conservation of energy is dead.

Re:There *is* someone who can read! (4, Funny)

X0563511 (793323) | more than 2 years ago | (#39291381)

Welcome to slashdot, "enjoy" your stay.

Re:LED Cooling (2)

RyuuzakiTetsuya (195424) | more than 2 years ago | (#39291259)

I want to see how this compares to cold cathodes. :)

Obligatory Simpsons Quote (5, Funny)

Jason Levine (196982) | more than 2 years ago | (#39291117)

"In this house we obey the laws of thermodynamics!"

Check the Cables (0)

Anonymous Coward | more than 2 years ago | (#39291123)

A loose connection may be skewing the results.

Re:Check the Cables (1)

X0563511 (793323) | more than 2 years ago | (#39291403)

Yea, I'm sure the research team didn't think to check their equipment after repeatedly getting totally off-the-wall results.

Or, you could try reading summary.

Not breaking any laws (5, Informative)

barlevg (2111272) | more than 2 years ago | (#39291125)

From the article: "The researchers didn’t try to increase this probability, as some previous research has focused on, but instead took advantage of small amounts of excess heat to emit more power than consumed. This heat arises from vibrations in the device’s atomic lattice, which occur due to entropy." The other thing to note is that these LEDs are being run at REALLY low power.

Re:Not breaking any laws (0)

afidel (530433) | more than 2 years ago | (#39291225)

Yes but taking advantage of entropic heat to generate coherent light would appear to violate the second law.

Re:Not breaking any laws (0)

Anonymous Coward | more than 2 years ago | (#39291343)

Yes, it's an electrical laser but in solid, not gaseous, form. Put simply, in deference to you, afidel, it's like lasing a stick of dynamite. As soon as we apply a field, we couple to a state that is radiatively coupled to the ground state. I figure we can extract at least ten to the twenty-first photons per cubic centimeter which will give one kilojoule per cubic centimeter at 600 nanometers, or, one megajoule per liter.

In other words, what you wrote went a little over my head.

Re:Not breaking any laws (4, Insightful)

X0563511 (793323) | more than 2 years ago | (#39291431)

Why? Entropic heat is energy, and so is light. What's so broken with converting one to the other?

Re:Not breaking any laws (4, Insightful)

systemeng (998953) | more than 2 years ago | (#39291453)

Why? It's conceptually equivalent to operate a thermoelectric module in reverse to get electrical energy and feed it into an LED to make light. In essence, you have made a heat pump with the LED.

Re:Not breaking any laws (5, Insightful)

snowgirl (978879) | more than 2 years ago | (#39291521)

Yes but taking advantage of entropic heat to generate coherent light would appear to violate the second law.

No, it doesn't, as long as the entropic heat being exploited costs more to organize than to disperse in the first place.

Namely: it would take more than the 39 picowatts of energy being generated to produce the heat to provide the additional 39 picowatts of energy.

The world is full of things that naively contradict the 2nd law of thermodynamics, because people misunderstand that you can have a localized violation of the 2nd law of thermodynamics, as long as the entire closed system that it is in counters that localized violation.

Why oh why oh why... (0)

Anonymous Coward | more than 2 years ago | (#39291149)

Does Slashdot keep jumping on the band wagon of snake oil and miracle cures to every problem on the planet?

What morons keep publishing this shit on /.? Better yet, what morons believe it?

Re:Why oh why oh why... (1)

Anonymous Coward | more than 2 years ago | (#39291497)

Even better yet, what morons made ignorant comments that were fully explained in the article?

Homer Simpson (-1, Redundant)

ender9441 (1358347) | more than 2 years ago | (#39291151)

In this house, we obey the laws of thermodynamics!

The Law (5, Informative)

Anonymous Coward | more than 2 years ago | (#39291155)

For those wondering about conservation of energy, it's intact. The extra energy comes from heat / vibration in the system.

For those concerned about the second law of thermodynamics, it's not specifically addressed in the article, but the smart money's on entropy increasing in this experiment. The second "law" is really just statistics though (law of large numbers anyone?), and as with most statistics people are still arguing about what it really means. See http://en.wikipedia.org/wiki/Second_law_of_thermodynamics#Controversies and http://en.wikipedia.org/wiki/Fluctuation_theorem

I wonder.... (0)

Anonymous Coward | more than 2 years ago | (#39291169)

Put the LED in a vacuum in chamber that doesn't let light back in... and then leave it on for as long as possible. How cool would the LED make itself before it breaks? Absolute zero? Probably not, but it would be a cool experiment to try.

Re:I wonder.... (2)

tibit (1762298) | more than 2 years ago | (#39291427)

Given that we can cool stuff down to less than a nanokelvin IIRC, and it took some ingenuity (Nobel prize for Bose-Einstein condensate), I doubt this LED will come anywhere close.

Sharc attack (1)

drainbramage (588291) | more than 2 years ago | (#39291179)

The lasers mounted on their 'Symmetric Hybrid Analogue Reflecting Chronometer' bounced back doubling the measured light output.

I don't think it violates any laws (0)

Anonymous Coward | more than 2 years ago | (#39291183)

As far as I can tell, this doesn't violate any laws if the LED is taking energy from the surrounding environment, in addition to the electrical energy, in order to produce optical energy.

Dare we consider... (0)

nani popoki (594111) | more than 2 years ago | (#39291185)

That we have yet another Cold Fusion experiment?

Nothing violates the first law in this universe (0)

Anonymous Coward | more than 2 years ago | (#39291193)

No, it is not. The linked article is quite clear: the LEDs are geting colder, so the extra power output comes from the environment.

Now, 230% efficiency suggests that it is operating as a >100% efficiency heat pump, and that's also impossible. It might be decomposing itself in an endothermic(sp?) chemical reaction, or something.

against known laws? (3, Funny)

alienzed (732782) | more than 2 years ago | (#39291197)

Definitely GPS timing error.

Can't break a fundamental law of physics (-1)

jweller13 (1148823) | more than 2 years ago | (#39291221)

Obviously it can't break a fundamental law of physics. Either the results are incorrect or they haven't accounted for some other mechanism in play.

Re:Can't break a fundamental law of physics (-1)

Anonymous Coward | more than 2 years ago | (#39291295)

You are an idiot.

Re:Can't break a fundamental law of physics (2, Informative)

Anonymous Coward | more than 2 years ago | (#39291405)

A third option is that you didn't read the article.

Re:Can't break a fundamental law of physics (0)

Anonymous Coward | more than 2 years ago | (#39291417)

herpa derp!!

What IS physics? (1)

Anonymous Coward | more than 2 years ago | (#39291235)

"Physicists from MIT claim to have demonstrated that an LED can emit more optical power than the electrical power it consumes. "

Bazinga!!

No it does not violate the first law (0)

ninjackn (1424235) | more than 2 years ago | (#39291247)

While my knowledge and understanding is limited I think that the extra power in the light output comes from heat. So light power out is greater than electrical power in but if you consider thermal power AND electrical power then total efficiency is under 100%. Thus the first law of thermal dynamics is safe.

Can I place my order... (1)

bwcbwc (601780) | more than 2 years ago | (#39291253)

for a glow-in-the-dark refrigerator now?

It sounds like it violates the 2nd and 3rd laws of thermodynamics if not the first.

Re:Can I place my order... (0)

Anonymous Coward | more than 2 years ago | (#39291503)

RTFA noob.

Kvothe did it first (4, Funny)

ShakaUVM (157947) | more than 2 years ago | (#39291267)

It's a good example. The hub of a wagon wheel will be warm to the touch. That heat comes from the motion of the wheel. A sympathist can make the energy go the other way, from heat into motion. I pointed to the lamp. Or from heat into light.

There was an art to choosing your projects in the Fishery. It didn't matter if you made the brightest sympathy lamp or the most efficient heat-funnel in the history of Artificing. Until someone bought it, you wouldn't make a bent penny of commission.

Article not as bold in its claim (2)

retroworks (652802) | more than 2 years ago | (#39291269)

I didn't follow through to the abstract, but the article didn't claim to be creating net energy. There could be other causes for more net energy emitted than applied, such as the device being on fire.

It draws it's energy from it's environment (0)

Anonymous Coward | more than 2 years ago | (#39291273)

It cannot violate the laws of thermodynamics, there must be an energy source that is unaccounted for. Some time ago, Prof. Claus Turtur made a straightforward calculation that the electric field emitted by a charge carrier, such as an electron, emits energy. This energy does not come out of nowhere, it is continuously converted by the charge from the zero-point field or whatever you may like to call it. I personally like to call it the aether.

See his article "Conversion of the Vacuum-energy of electromagnetic zero point oscillations into Classical Mechanical Energy" : http://www.wbabin.net/physics/turtur1e.pdf

In the chapter "A circulation of energy of the electrostatic field" (pages 10-14) he makes a straightforward calculation of the energy density of the static electric field surrounding a point charge using nothing more than Coulombs law and the known propagation speed of the electric field, the speed of light, and shows that there must be some kind of energy circulation between the vacuum and charge carriers:
-:-
        If electrostatic fields propagate with the speed of light, they transport energy, because they have a certain energy density. It should be possible to trace this transport of energy if is really existing. That this is really the case can be seen even with a simple example regarding a point charge, as will be done on the following pages. When we trace this energy, we come to situation, which looks paradox at the very first glance, but the paradox can be dissolved, introducing a circulation of energy. This is also demonstrated on the following pages.

        The first aspect of the mentioned paradox regards the emission of energy at all. If a point charge (for instance an elementary charge) exists since a given moment in time, it emits electric field and field’s energy from the time of its birth without any alteration of its mass. The volume of the space filled with this field increases permanently during time and with it the total energy of the field. But from where does this “new energy” originate? For the charged particle does not alter its mass (and thus its energy), the “new energy” can not originate from the particle itself. This means: The charged particle has to be permanently supplied with energy from somewhere. The situation is also possible for particles, which are in contact with nothing else but only with the vacuum. The consequence is obvious: The particle can be supplied with energy only from the vacuum. This sounds paradox, so it can be regarded as the first aspect of the mentioned paradox. But it is logically consequent, and so we will have to solve it later.

[...]

        Important is the conclusion, which can be found with logical consequence:
        On the one hand the vacuum (= the space) permanently supplies the charge with energy (first paradox aspect), which the charge (as the field source) converts into field energy and emits it in the shape of a field. On the other hand the vacuum (= the space) permanently takes energy away from the propagating field, this means, that space gets back its energy from field during the propagation of the field. This indicates that there should be some energy inside the “empty” space, which we now can understand as a part of the vacuum-energy. In section 3, we will understand this energy more detailed.

        But even now, we can come to the statement:
        During time, the field of every electric charge (field source) increases. Nevertheless the space (in the present work the expressions “space” and “vacuum” are use as synonyms) causes a permanent circulation of energy, supplying charges with energy and taking back this energy during the propagation of the fields. This is the circulation of energy, which gave the title for present section 2.2.

        This leads us to a new aspect of vacuum-energy:
        The circulating energy (of the electric field) is at least a part of the vacuum-energy. We found its existence and its conversion as well as its flow. On the basis of this understanding it should be possible to extract at least a part of this circulating energy from the vacuum – in section 4 a description is given of a possible method how to extract such energy from the vacuum.
-:-

Also see: http://peswiki.com/index.php/Article:Free_Electric_Energy_in_Theory_and_Practice

Its not wrong, its stupid. (1)

norteo (779244) | more than 2 years ago | (#39291281)

From the Article: "When the LED gets more than 100% electrically efficient, it starts to cool itself down, which is another way of saying that it's stealing energy (in the form of heat) from its environment and converting that heat into those over-unity photons." The article doesnt say what happens when the led finishes cooling down. is it still above 100% efficient?

Re:Its not wrong, its stupid. (1)

Oswald McWeany (2428506) | more than 2 years ago | (#39291501)

I presume it will hit an equilibrium where the heat it is turning into photons matches the same rate as heat in the surrounding area conduct with the LED to warm it up.

Thus- it will give off light just as quick as it can conduct heat from the surrounding environment.

A misleading and hyperbolic Slashdot story? (2)

tylersoze (789256) | more than 2 years ago | (#39291287)

Wow I'm totally shocked, what's the world coming to? :) All you have to do is actually read the linked article to see there's no sort of thermodynamic violation of any sort implied, not that most of the people posting here will bother to RTFA.

No (0)

Iniamyen (2440798) | more than 2 years ago | (#39291291)

They obviously need to take a look at what their "closed system" is. Once they do, they will find that the first law of thermodynamics is in no danger of being violated.

There is some confusion here (5, Funny)

circletimessquare (444983) | more than 2 years ago | (#39291297)

as most people think Light Emitting Diode when they hear LED.

But in this experiment they are referring to a Large Entropic Dilemma.

So the results make perfect sense.

The answer to global warming? (0)

Anonymous Coward | more than 2 years ago | (#39291299)

Seems to break the laws of entropy, but take a trillion of these and point them at a solar power plant? Pulls the heat out of its surroundings, creates enough electricity to power the LEDs *AND* to provide a modest amount of power also. Now how the hell do we make a trillion of these? lol

Pooooof (2)

geogob (569250) | more than 2 years ago | (#39291305)

Now, all we need is a solar cell with 100% efficiency and we're in business.

Just imagine... (0)

Anonymous Coward | more than 2 years ago | (#39291309)

A Beowulf cluster of 20 picowatt LEDs!

Sorry, it had to be said.

Heat Energy... (3, Interesting)

Oswald McWeany (2428506) | more than 2 years ago | (#39291313)

Surely if this is true the "light" is not the big story.

If you can take "heat" and convert it into another form of energy that is HUUUUUUUGE NEWS- yes I know, steam engines, etc, but they require a large difference in temperature.

Imagine if your fridge/freezer- GENERATED power- by taking heat energy and converted it into electricity?

Re:Heat Energy... (1)

Oswald McWeany (2428506) | more than 2 years ago | (#39291459)

And by the way- I know the energy gained is miniscule... but imagine what kind of cultural revolution it could inspire if we could convert heat energy into power efficiently.

All the air conditioning we apply- all the heat exchanges to cool down equipment- all the residual energy lost as heat in so many applications that we could potentially trap and turn into something usefull.

"Heat" is how energy is "lost" or "wasted" in most appliances.

Good time to RFTA (5, Informative)

mykepredko (40154) | more than 2 years ago | (#39291325)

Interesting to see the number of posts saying that this is absolutely not possible - reading through the article, it seems possible and maybe there is enough here to study the phenomena enough to warrant more investigations.

The LED seems to be emitting 69 picowatts (pico = 10^-12) when only 30 picowatts of electricity is being pumped in with a measurable decrease in the temperature of the LED. This implies that the LED is acting as a heat pump, converting heat energy into light. If you've ever seen a Peltier cooler in action (or worked through the operation), it seems like to me this is possible.

Note that the power level this phenomenon is observed at is extremely low - the result is maybe good enough for cooling a few molecules of beer - but I think there is something here that should be investigated to see if any usable applications could come out of it.

myke

Glowing metal (1)

z4ce (67861) | more than 2 years ago | (#39291357)

Is this effect they are explaining similar to how a piece of metal will glow when hot? I've always wondered how glowing metal aligns with the second law of thermodynamics. It seems to directly convert heat (lower order energy) to light.

When metal glows when hot is it consuming anything or utilizing the difference in temperature in some way?

Or said another way, if you put a piece of metal in a perfectly insulated hot box would it still glow forever?

Assuming they didn't screw it up.... (1)

gurps_npc (621217) | more than 2 years ago | (#39291359)

Then we need to go looking for possible other sources of power.

For example, is the LED getting colder? Could it be converting heat to electricity? Are magnetic fields near them weaker? Is the LED losing a minute amount of mass?

Can we try it again with 100 LED set at low power?

Can we set up a closed loop of a series of low power LED's illuminating a photovoltaic board?

Obligatory (1)

rastos1 (601318) | more than 2 years ago | (#39291361)

Obligatory wanna bet [xkcd.com] ?

Can someone please explain ? (0)

Anonymous Coward | more than 2 years ago | (#39291385)

Does this mean that one can use an array of such LED's to cool the ambient temperature while producing light at the same time ? It sounds extra-ordinary. Can we say goodbye to overheating cabinets ?

Lucky I am in grad school... (1)

some1001 (2489796) | more than 2 years ago | (#39291463)

To achieve this "above unity" efficiency, they are running these LEDs at 135 degrees C with a "light power" of 10^-10 watts.

So essentially, from my not-very-good understanding, they are able to exploit the motion of particles in the lattice due to heat (Kb*T) to overcome the energy gap in the diode. Hence the high temperature. I assume the wattage input must be kept low enough to not completely overpower this phenomena.

I would thusly conclude that the only reason why it can keep going with this >1 efficiency is because of the heat being supplied to the chamber in addition to the energy through electricity. Take away the heat, and it would slowly cool itself down.

FkAILZORS!? (-1)

Anonymous Coward | more than 2 years ago | (#39291471)

are a 7ew ggod a losing battle; insisted that When I stood for

In terms of a car... (0)

skrimp (790524) | more than 2 years ago | (#39291473)

It's like the alternator. It requires electrical excitement before it will produce electricity. But, once excited, and using the energy from the engine, it will produce more electricity than what was required to excite it.

So... (1)

Quiet_Desperation (858215) | more than 2 years ago | (#39291491)

When used as a heat pump, the device might be useful for solid-state cooling applications...

The logical conclusion is, of course, a glowing refrigerator.

I support this line of inquiry.

Didn't David Brin use this idea with lasers to keep his sun skimming ship cool, or did I dream that?

Re:So... (1)

Quiet_Desperation (858215) | more than 2 years ago | (#39291505)

When quote tags fail. Oh, for an "Edit" button on Slashdot, but I guess that's too hip or something.

Thermodynamics question (1)

Anon-Admin (443764) | more than 2 years ago | (#39291495)

I did RTFA but do have a thermodynamics question.

Thermodynamics is based on the idea that energy can be changed from one form to another, but it cannot be created or destroyed. It also supposes that the total amount of energy and matter in the Universe remains constant, merely changing from one form to another.

The second half of that appears to be wrong the total amount of energy and matter in the universe does not remain constant by my limited understanding of quantum mechanics and membrane theory. Potential particles are converted to particles of matter as they emerge from the plank level as a wave form.

Did I miss something?

This is why I love Slashdot- really BRIGHT news (1)

G3ckoG33k (647276) | more than 2 years ago | (#39291513)

This is why I love Slashdot- really BRIGHT news.

So shiny, and if these LEDs work, splendidly brilliant!

Cold? (3, Interesting)

wisnoskij (1206448) | more than 2 years ago | (#39291519)

So the lights sucking the heat out of the air and feel physically cold to the touch?
Does this 230% conversion ration only work in really high heat location or is this in room temperature?
Would this technology not really work in -40 degree winter environments?

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