Solar's had a pretty rough time breaking the ~40% efficiency level over the years, but Idaho National Laboratory researchers have apparently developed a nano-antenna array capable of collecting power not from photonic energy as is done today, but from infrared energy that could be harvested in any weather (or even at night). The cell production process is even supposed to be ridiculously cheap compared to making standard silicon photovoltaic cells, but, as always, there's a rub. The grid collects its oscillating IR energy at ten thousand billion times per second, which is proving to be a challenge to the nerds behind the tech, who are working on a way to convert that to the 50-60Hz power that the world uses. So yeah, it might be a few more years before this one pans out (if it does pan out).
[Via
EcoGeek]
posted Feb 2nd 2008 6:31PM
I really hope they can get this to work. All the advantages of solar with hardly the disadvantages. Kudos to the scientists for discovering it!
Hm... Alternating current at 60Hz changes polarity 60 times a second. AC oscillating at a billion (?) times per second changes polarity at a billion (?) times per second.
They have one thing in common: They change polarity on a specified interval.
Hey, researchers, if you are reading this, why not make a network of electrical diodes which allow current to only flow in one direction? Oh, wait, I just remembered, why don't you make a rectifier? That way you would be dealing with + and - like a battery. Then an inverter shall kick it back to 60Hz AC! Sparkling!
http://en.wikipedia.org/wiki/Rectifier
P.S: I know the idea is far fetched, but give it a try? What's to lose?
PS2: I accidentally figured out how to coax the commenting system. Click on the date of the post and click reply.
FTA:
One potential candidate is high-speed rectifiers, special diodes that would sit at the center of each spiral antenna and convert the electricity from AC to DC. The team has a patent pending on a variety of potential energy conversion methods. They anticipate they are only a few years away from creating the next generation of solar energy collectors.
@aguilz:
I'm not sure if you're aware how diodes work, but the problem is that they have a finite recovery time which limits their operating frequency. Commercial ultrafast diodes top out at a few GHz at best; I'm not sure where the latest research is at, but I don't think we're anywhere near the 10 THz (=10,000 GHz) speeds these guys are after.
@TreeTrunk
I know they do let current flow in one direction, but yes, I thought there should be some diode fast enough to deal with it. Factor in the recovery time and the current output will be a little seedy.
Out of curiosity, would an LED work? I know it can go AC and DC.
Yeah... (10^13) Hz could pose a problem to our power grid. ^^;;;
But, nonetheless, this seems crazy, efficient and awesome at the same time.
Not photonic?
What exactly is the particle of an IR beam i wonder...
Oh, right.
Not visible spectrum, and thus usable in more circumstances for a longer time, sure. But let's not make up science here.
Hopefully they can embed some kind of tiny uber-transformer or something and make this reality.
Then again the people at engadget have about as much scientific background as people who claim we are "destroying" energy by using it up so fast. Physics doesn't matter, nor does conservation of Energy.
Hey did you know you have less KG on the moon? It's true!
/Sarcasm
A bit Problematic I must admit.
Spell check "ridiculously"
Few more years? Can't they find a solution by the end of the week jeez. Especially the night usage makes this very intresting for being able to recharge at any given time.
Also, you could probably use it to recoup some lost energy from machines that bleed off a lot of heat.
Ermm ... IR radiation is "photonic", in that the IR band is part of the EM spectrum, which last time I looked was all about the photons .... the original article is here: http://www.inl.gov/featurestories/2007-12-17.shtml, without the misinterpretation.
Is that Mitt Romney?
No.
woops, i'd remove that one if i could figure out how
IR and the visible spectrum are all part of the electromagnetic spectrum, which is photonic under the particle view of EM. There is no fundamental difference between IR and the visible spectrum other than frequency and wavelength.
I don't really get why the article claims energy conversion is a problem. Converting to 50-60Hz AC is one of the last steps on an energy production process before transmission onto the AC grid. If the device captures energy, there's an endless number of ways to convert it to energy we can use, so what's holding this up? Just because the energy captured by the solar cells is AC, doesn't mean they have to convert everything electrically. There are plenty of energy production methods that are not done electronically. Nuclear power plants for example use the energy produced by the nuclear reaction to heat up water, which produces steam to turn the turbines that produce AC electricity. As long as energy is produced, it can be converted to AC. It makes me wonder why they are putting so much emphasis on the energy conversion hurdle of this device. Perhaps it's because the efficiency of these new solar cells are so low that they are looking for a really high efficiency conversion tool.
Storing energy removes some efficiency. Even something like a battery is finite. I would imagine that something like this is in its very early stages and cannot afford any losses.
Energy storage is a problem of modern solar cells. They absorb energy only part-time (in visible sunlight) therefore they must store energy for night use or not be used during this time. One major advantage to this is direct energy 24/7. "Direct energya" straight from source to use is far more efficient than storage and should be sought after. cut out the middleman
***"direct energy"***
And why not use a battery as the rectifier/the way to smooth it out ?
It's a far easier option than having to build into the system even more complexity !
Then if you want to create AC again all you have to do is to add in a transvertor - and as someone else's said, you can use the heat created to create more electricity... though I doubt we've found perpetual energy JUST yet...
Love the idea but if these geeks can't figure out a rectifier after designing this i would be appalled but then again would it really be that odd?
-1 for the misleading title.
They are obviously outputting energy, it's just not something we can use right now.
There seems to be a whole bunch of mistakes in this post
Ya know, this might just revolutionize the energy industry. Think about the implications this has nuclear energy as well: there's probably a lot of energy lost to IR in the water heating cycle, and this could capture a lot of that back. Hell, that would work for any heat-producing power system. Also think about putting these around computer chips, not only does it absorb the heat, dropping the temperature of the chip but it recycles the lost energy!
Let us not forget that just as all the carbon may be sapped from the earth, so too may the space under the sun allowing for capture of its energy. Everything is finite and nothing will allow us to be as glutenous as we've been, so don't get your hopes up for such a greedy cause. Its about using less energy not gaining more or its back to sticks and stones we go.
Glutenous? I suppose we could plant more wheat or rice. Both have a lot of gluten. Mmmm... Mochi...
Gluttonous might be the word you are looking for.
if I were them I would be working (or have grad students working) day an night to get this on the market as quickly as possible! If they can make this in large quantities, cheaply, this could do so much good for the world. and hopefully make them lots of money without imposing excessive cost to the public.
Ten thousand billion... why not just say 10 trillion?
Sounds more scientific? More epic? who knows
Because American have a thousand billion as a trillion/ thousand million as a billion, where as most other places use a billion billion/ million million. TBH I'm not actually sure what they mean in the article as it's based in america, so they could mean either a thousand million million, or a thousand thousand milion, would be much easier to just put a number.
haha, that's the first thing i thought of when i read it...
haha, that's the first thing i thought of when i read it...
If only they would let Apple engineers work on it. It'd be ready by Christmas.
If they let Apple work on it, it'd be extremely light--lighter than Air, in fact--but would lack certain basic functions like an optical drive.
...wait, what were we talking about again?
Maybe,
But the cost may be too high to be a viable solution.
Though, If they make it pretty, despite it's efficiency, it will sell.
says "The cell production process is even supposed to be ridiculously cheap compared to making standard silicon photovoltaic cells, "
No, but it would be ready by MacWorld SF 2009.
A few things to note about the article. Photonic? All forms of light covering the EM spectrum are present as photons (and/or wave - see bragg experiments).
Thus IR 'light' is also photonic. The article suggests that there is a problem converting the frequency of light to the 50 - 60Hz range. Considering normal light (400 - 700nm) has a wavelength in the 10^13 range, why is converting IR radiation to this band so much more difficult than visible?
A key reason why they are having trouble harvesting energy from this is that it may violate thermodynamics. You cannot harvest energy from heat unless you have energy flowing from an area of greater temperature to one of lower. Since IR energy emitted at night is thermally generated with a blackbody spectrum that corresponds to the temperature of the environment and since the photovoltaic cells are at this same temperature, you cannot extract any energy. You'd need to cool the cells, which itself would require energy. Another way to look at it is that although the photovoltaics are receiving IR emitted by the environment, they are also emitting IR back to the environment.
These panels aren't absorbing the kinetic energy, they're reacting to IR light like normal Photovoltaic cells react to visible light. Therefore thermodynamics don't factor in.
Think of it as solar cells absorbing light we cant see.
- there's probably a lot of energy lost to IR in the water heating cycle [in nuclear reactors] -
Not to mention lining your car engine, your air conditioner, your gas furnace, your steel mill, your local volcanoe, your oven, your water heater, your computer, your incandescent light bulbs (who still has those?).
If it is 'ridiculously cheap to make', then you could put it in everything and, like regenerative braking, recapture a percentage of the heat 'waste' product of electricity doing work.
If I remember right, please no flames, light-emission is from electrons dropping excitation shells. Reverse is light/photon being absorbed and transitioning electrons to higher shells. So, fully reversible, and IR-in to electricity when drained away and IR-out when electricity is applied.
Heck, if it absorbs IR and frees an electron, can it be efficient at radiant heating in the reverse? Push electrons into it and the material might emit IR. Probably not 1 electron:1 photon, but with UV maxing at 1 electron:2.5 photons.
Heck, if it absorbs IR photons, I wonder if you could line your refrigerator with it, hook the fridge-grid up to a capacitor and for every electron the capacitor sucked up based on just how much it LOVES to soak-up charge, it would suck up an IR photon from the fridge cavity. Capturing that IR-photon before it collided and was absorbed by another atom would block kinetic energy transfers essentialy cooling the contents. Since you have to wait for atoms to randomly release kinetic energy and let that IR photon hit the wall, it probably wouldn't be rapid cooling, but it would be consistent.
But then again, if the capacitor is an ultracapacitor, it could pull so hard that any IR photons heading 'away' from the object would never return and thus the item would cool. After all, current refridgeration works by cycle of adding cold air molecules, which randomly absorb IR from food, then transfer that IR energy to cooling coils, which then carry it via compresor/condensor to exterior air and air molecule is cold enough again that it would be happy to absorb an IR photon.
In theory, you could use it to quickly cool stove-tops, hotplates and ovens to make them instantly safe to touch, just set the circuit that when heat is turned off, capacitor is turned on. You could even use the capacitor in reverse and release the energy back and quick-start the heating cycle.
Could you use these as better night-vision goggles? If they are this good at picking up IR, then could you put them in IR lenses and hook them up to visible OLEDs?
oh4real
Grade students already work day and night, trust me.
Many comments seem to suggest that these guys in Idaho just need to get off their duffs and convert this to electricity already, it's so easy! Just slap a rectifier on it. It's far from trivial, as the article indicates. Conventional photovoltaic solar cells convert photons into electrons, producing DC current. While not highly efficient, those electrons are easy to harness. The concept in this article literally uses tiny antennae, very small version of what would be used for radios, TVs, cell phones, etc. As such, they operate based on resonance and produce AC currents which need to be rectified or stepped down to usable line currents. Diodes and other electrical components are required to do this, and while available to support radio/TV/cell phone frequencies, finding (or making ) electrical components compatible with optical frequencies is fantastically difficult, much less dealing with the sensitivities of the overall circuit itself. Typically, you need discrete devices per each antenna, and since these antennae are nano-scale to be able to receive optical frequencies, you are talking about millions or billions of devices on a given sheet. Similarly, to reach usable signal levels, you need a lot of antennae at this size, and any antenna designers will tell you that grouping multiple antennae together makes the whole process very complex. Millions or billions of closely spaced antennae would be, literally, a nightmare. So, while this technology looks interesting, primarily in their ability to print large areas of nano-scale antenna, lots of long days and nights will be needed, over many years, to make this thing potentially viable as an energy capture device.
There are no rectifiers that work at Terahertz frequencies. These frequencies are orders of magnitudes higher than the microwave that we deal with today. Do you realize how difficult it is to design circuits that operate in the Ghz range?
That should be "grad" students. Maybe I was thinking of grade school students, who typically barely work day, and never work night.
Does this mean that I can soon use my remote control to power my house?
Or perhaps lazer tag arenas can be padded with these in order to capture energy from the wasted shots, or even padded around tv's in order to capture energy from the extra IR light. I know that the energy captured would not be significant, but it would still be better than nothing.
WTF? They discovered new way of getting energy but never heard of a rectifier?
dude, why the smartass 'but can't output energy' comment?
"Mile @ Feb 2nd 2008 8:32PM
If only they would let Apple engineers work on it. It'd be ready by Christmas."
How you managed to work Apple into this thread is impressive in a bad way.
Hey, not necessary to output the power.
If the array harvests on the IR - which is in effect *heat* - can we chill thing with it?
I mean, can it be used as additional layer of isulation?
what a great discovery.
DarkLightConnection:
Congratulations, dumbass. Who would have though that you would be able to come up with the idea of using a rectifier and the scientists who developed this technology just completely forgot about their basic electronic principles. Do you want to explain ohms law to them too, genius?
Or did you not stop to think that semiconductors don't react well to operating at extremely high frequencies?
Smoothing high frequency signals isn't easy. It's hard for conventional silicon chips (e.g. diodes and caps) to respond in time when the period of oscillation is that small.
Presumably the high-frequency wave could still be used for applications that don't depend on a DC current, like heaters or incandescent lights?
I do hope they figure it out.
It's not as simple as just "slapping" on a rectifier as many of you seem to be suggesting. Just like Matt said, semiconductors do not respond well to high frequencies. All sorts of weird things happen: the wires act as inductors and anything with resistance acts as a capacitor and you end up with almost all your energy lost if you try to put semiconductors between the source and the output.
A diode breaks down when submitted to that kind of load: we're talking about an electron rushing back and forwards through it 10 billion times in a second. And it has to decide, in 5 billionths of a second wether or not to let it through.
A great discovery, but it'll need another one in semiconductors to come to fruition.
I think the smartass comments are in part due to engadget blatantly aiming this post at them, in order to get more hits. Flippantly suggesting that they understand fully what these scientists/engineers are doing.
Over the years i've gotten more and more disgusted by the way engadget just writes for ads.
Try reading damninteresting.com . no ads, really good pieces of technology writing.
if the system is as cheap as its purported to be, rather than a rectifier couldnt you use just one diode for half the potential power, and allow the durability and application etc. of the material to be developed, ultimately allowing for the output to be doubled when high speed rectifiers are developed? i realize that the semiconducter in the diode still wouldnt be fast enough to switch, but if one applied even a small voltage in parallel simultaneously, the gate would stay open . . . actually, even apply that to the gate in the rectifier. Or, would the diode, once open, pass current in either direction? I wish I knew more but it would seem that a secondary current could easily resolve the issue of high speed switching.
I don't get it, how can they work but not output power?
-----------------------
http://www.xenu.net
"I don't get it, how can they work but not output power?"
The work because they are creating a signal, We just cant convert that to a usable form of power yet.
if the system is as cheap as its purported to be, rather than a rectifier couldnt you use just one diode for half the potential power, and allow the durability and application etc. of the material to be developed, ultimately allowing for the output to be doubled when high speed rectifiers are developed? i realize that the semiconducter in the diode still wouldnt be fast enough to switch, but if one applied even a small voltage in parallel simultaneously, the gate would stay open . . . actually, even apply that to the gate in the rectifier. Or, would the diode, once open, pass current in either direction? I wish I knew more but it would seem that a secondary current could easily resolve the issue of high speed switching.
if the system is as cheap as its purported to be, rather than a rectifier couldnt you use just one diode for half the potential power, and allow the durability and application etc. of the material to be developed, ultimately allowing for the output to be doubled when high speed rectifiers are developed? i realize that the semiconducter in the diode still wouldnt be fast enough to switch, but if one applied even a small voltage in parallel simultaneously, the gate would stay open . . . actually, even apply that to the gate in the rectifier. Or, would the diode, once open, pass current in either direction? I wish I knew more but it would seem that a secondary current could easily resolve the issue of high speed switching.
I'll explain this here again since the "reply" function to my original message isn't working. It's not possible to take infrared light emitted by the ambient environment, absorb these by photovoltaic cells at the same temperature as the ambient and produce usable power. This is a violation of thermodynamics. Imagine this were possible. You could then take the produced power and use it to heat your photovoltaic array. The ambient would grow cooler for having lost energy in the form of IR emissions and the array would grow warmer. The net result would be energy transferred from one object, which is growing cooler, to another, which is growing warmer. It's a basic principle of thermodynamics that this cannot happen.
Another way to view this is that the photons emitted from a warm object arise from some of the kinetic energy of the moving atoms in the object being converted to photons. Deriving net usable energy from this is therefore the same as extracting usable energy from the thermal motion of atoms. Indeed, you can take any resistor and measure a fluctuating voltage across it equal to an RMS value of sqrt(4*k*T*R*B), where T is the temperature, k is Boltzmann's constant, R is the resistance and B is the bandwidth over which you're measuring. This is very much like the oscillating signal being observed in the photovoltaic cells in the article. However, you cannot rectify this and extract net power because any element you add to do so also produces similar power in the opposite direction as long as everything's at the same temperature. If you could, we'd be able to extract energy any time we wanted from the thermal energy of any object. This is possible, but only if we have a thermal reservoir of cooler temperature at our disposal as well.
David
The temperature of the ground is slightly higher than that of the air. It's possible to extract work from this temperature difference- this is already done in ground-source heat pumps. This idea would do this in a different way, using electrical resonance at IR frequencies to obtain electricity directly.
p.s- reply works if you click the post date/time first.
David, I get what you're saying and I'm not even a physics person. From what I understand, however, infrared radiation is not the same thing as heat. This contraption here does not simply "absorb" the heat around it, but treats the infrared radiation like visible light and absorbs that, much like how infrared lenses on cameras work.
My other question, however, is this. Why wouldn't these scientists also be working on ways to absorb ultraviolet radiation as well? We might as well make use of all of the energy coming from the sun...
hmmm looks like Mitt Romney to me.. ;-)
Cool then...
Hooray, solar power which works when it's warm rather than when it's light!
Solves nothing of course, since a) There's a fairly strong correlation between natural light levels and external heat, and b) coldness, along with darkness, is one of the biggies in terms of domestic power requirements.
Roll on the days when everyone has a supercapacitor in their attic...