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Capturing Solar Power With Antennae
necro81 writes "Researchers at the University of Missouri and the Idaho National Laboratory have demonstrated a new method of capturing solar power. Rather than using semiconductors to capture photons of sunlight, they fabricated small coiled antennae (several um square) that resonate with the wave nature of light. The antennae are tuned towards midrange infrared light (5-10 um), which is abundant on our cozy-warm Earth — even at night. They also demonstrated a way to imprint these coils on a substrate, like how CDs or vinyl records are produced, but could be scaled to roll-to-roll mass production. The usual caveat applies: it may be 5-10 years until this could hit the market."
If these become commercialized it will be a disaster. These micro antennae will effectively absorb midrange IR light and reflect everything else back out as polarized light minus the IR. This is sure to cause skin cancer, retinal damage and other maladies.
Think about it this way: you require an across the board, nutritious meal of food as healthy fuel. Take away the IR light and you're eliminating full spectum light which is essential for health and nervous system maintainence. Make the remaining light polarized and *bam*: a public health disaster in the making. Subluxations Galore.
I was at a seminar in which suntanning booths ("Cancer Coffins") and their effects on spinal nerve health were discussed (hint: don't tan in those things!) The presenter is a well respected chiropractic doctor and researcher in Florida. In fact you can find his his videos on YouTube (look for "Maximized Living") with many thumbs up ratings.
At the break, we were chatting and he said he had seen an increase in the number of serious vertebral subluxations in people who went *TO 3D MOVIES*.
He went on to explain his theory. It seems that the 3D movies these people went to were all the type with strong polarized lighting being projected on the screen. *NONE* of his patients were at the red-blue type of 3D movie. Not one.
So these innocent people go sit in these movie houses as a treat and end up bathing themselves in dangerous polarized lighting. The worst bit is that so many kids movies are 3D now. Young spines and nervouse systems are being destroyed by this nonsense. No wonder we're seeing an increase in the number of parents bringing in their children for chipropractic care.
The public will never hear of this as big media and hollywood will silence critics..
Think about it: after a long movie, doesn't your back feel kind of stiff when you get up? That's caused by micro-subluxations. Moving around breaks those up without any long term damage, but go home and sit on the couch and they grow into full-bore, dangerous, health damaging subluxations. Those are, frankly, worse than cancer.
Think about that before you put up these solar cells.
Take care!
Bob
PS: I can only post once or twice a day (thanks, BP shills) so I may not be able to reply.
Chiropractic Saves Lives!
http://xkcd.com/899/
It will still be 5-10 years away.
SJW: Someone who has run out of real oppression, and has to fake it.
Antennae are for bugs.
Haida Manga
The summary fails to mention the most important advancement here: 90%+ efficiency. That's a game-changer for solar power.
"When information is power, privacy is freedom" - Jah-Wren Ryel
Currently, they can only make these these things work with a flying car as the substrate.
Rectifier? Just sayin'. Can't run your stuff off of THz electricity.
Greeks were way ahead of this with their "key pattern" motif. Who knew it would be useful in ways other than decorative when made microscopic and etched on a semiconductor substrate?
Anybody else read this and immediately think that it might potentially solve the problem of biologically powering medical implants that was mentioned in a story on Slashdot about a week ago?
Check out my sci-fi/humor trilogy at PatriotsBooks.
Beware the PDF link
... to etch an antenna at the wavelength of 0.000001 meter? Well, OK, it's not trivial. But we do have things like lasers that can etch chemicals at that size and smaller. Then we need a way to transfer that etch to conductive metal, add rectification to make it usable and collectible, and have our own little power sources. A flat panel might do if the current level doesn't burn up the collection tap point.
now we need to go OSS in diesel cars
so, does this mean they are making vibrators? i thought vibrators used electricity.
Having to work for a living is the root of all evil.
Phrenologically speaking, your entire post is really lumpy. From a cooking standpoint, your pot is cracked. And scientifically speaking... well, why bring science into it now?
I've fallen off your lawn, and I can't get up.
Did anyone else notice this paper was written in 2008? That means we are only 2-7 years away! I'll be powering my home with antennas that cover my roof in 2 short years!
If this is such big news, why did it take 3 years to make it to /.?
Don Lancaster described this process years ago. The trick is the tiny diode at the bottom of the antenna to turn the AC into DC. It has to handle 400 - 800 THz. Plausible, but difficult. 5-10 years really means they have no idea when they'd be able to produce this in industrial quantities.
All ideas^H^H^H^H^Hprocesses in this post are Patent Pending. (as well as the process of patenting all postings)
When Tesla was determining the resonant frequencies of the earth to potentially transmit unlimited electric power, he also recognized frequencies that acted as a damping field to nullify electric power. With the advent of the wireless and Tesla's unique investigations into broadcasting electricity, a dozen or more inventors thereafter announced their own means for transmitting electrical energy without wires. One British inventor, H. Grindell-Matthews, actually demonstrated his "mystery ray" apparatus in 1924 to a Popular Science Monthly writer in London (See: Pop. Sci. Monthly, Aug. 1924, P. 33). When his beam was directed toward the magneto system of a gasoline engine, it stopped the system. Afterwards, it ignited gun powder, lit an electric lamp bulb from a distance and killed a mouse in seconds! Grindell-Matthews said the secret was involved with the "carrier beam" he used to conduct a high-voltage, low-frequency electrical current. During 1936, Guglielmo Marconi experimented with extremely low frequency (ELF) waves and displayed their exceptional ability to penetrate metallic shielding. These waves could affect electrical devices, overload circuits and cause machines like generators, electric motors and automobiles to stall. Diesel engines, which do not rely on electrical ignition, were not affected. Mysteriously, Marconi's research on the subject was never found after the war.
Slashes Dot is turning to Shit.t.
Someone made a new break thru invention and they should quickly patent it!
Never mind, patents are useless because no one invents anything by themselves any more.
This is, of course, utterly useless for harvesting power from ambient thermal radiation. Even if you can make a diode that's remotely capable of rectifying current at high enough frequencies, the diode has to be kept colder than the source of the radiation. It's the electrical analog of a Brownian ratchet.
Picking up a bit of the IR tail that conventional photovoltaics don't catch? Maybe, but there isn't very much power down there even if you got the efficiency usefully high. Turning ambient heat into usable energy? Sorry, no.
http://personalpages.manchester.ac.uk/staff/A.Song/research/BallisticRectifier.htm this is the only link I could find , I saw this topic some time ago - the ability to build nano structures may solve the rectification - I am sure there was another paper with a different device configuration but I'll never find the thread now - doesn't make this tomorrow but it means a lead on both ends
The usual caveat applies: it may be 5-10 years until this could hit the market.
The solar constant caveat applies: it will always be 5-10 years until this could hit the market.
ALWAYS.
This is the problem with solar power, it's mostly home owners who are buying them and the systems cost so much it takes decades to break even (if purely doing it for cost reasons, not CO2).
So once a better technology comes along you have to junk the old tech and you may never break even.
What are they using to rectify the signal to convert to DC?
Unobtainum diodes. They don't actually know how to do that.
Terahertz diodes do exist. Low-cost, high-efficiency, integrated terahertz diodes, no. But as work proceeds on terahertz electronics, someone may solve that problem. Each nanoantenna needs its own nanodiode, so the diodes have to be fabricated on the substrate with the antenna, which complicates the fab problem. The enthusiasm about roll-to-roll low cost fabrication in the article is premature. We'll probably see this working first on a wafer, and it may not be cheap.
Even if it's expensive, there's an initial market for satellite power panels. The performance improvement would be worth it.
The individual nantennas can absorb close to 90 percent of the available in-band energy.
Which is good for communications, where you want to exclude all but the target band. It could even work for power, providing the light source is a laser. But resonance methods aren't very good for capturing energy from broad spectrum sources like the sun.
I predict that this technique will never gain traction for solar energy. However, it might replace photodiodes for fiber optic communications.
Yeah, I'm still waiting on the amazing solar innovations that were breathlessly announced five years ago to hit the market.
Proverbs 21:19
Is this 5-10 flying car years? Similar to dog years but in the other direction. 1 flying car year equals 1 normal human lifespan, apparently...
Is it possible that a widespread use of such antennas will lower the average temperature since it is tuned to mid range infra-red? They can sell it being super eco friendly :-)
Summary: They designed nano-scale devices that behave as antennas at infrared frequencies, meaning that infrared light induces a THz current in the antenna. They then proceeded to manufacture a few one-off test pieces that performed well and are now using a master pattern to roll/stamp the devices onto a film (though the full results of that weren't shown or aren't known yet).
We don't typically think of stuff like light as being susceptible to this sort of thing because we haven't been able to make the antennas small enough to work at those wavelengths. In theory the technique can be used to design antennas that capture any part of the electromagnetic spectrum.
The key piece they are missing is cheap efficient THz rectifiers that can convert the induced AC current into usable DC voltages. Not a small problem but not an impossible one either.
Natural != (nontoxic || beneficial)
Similar tech has been used on the last few generations of Keyhole birds. They solved the rectification problem by doing everything analog and analyzing the interference patterns (at a much more reasonable speed). Still used some pretty nasty GaAs circuits though...
I'd expect something useful (besides satellite imaging) could be done with a huge array of these.
AC for obvious reasons.
From the summary "The antennae are tuned towards midrange infrared light (5-10 um), which is abundant on our cozy-warm Earth â" even at night."
But you can't extract work from a system which is in thermal equilibrium. This can't work unless the 'solar panels' are colder than the ambient night time radiation, which seems unlikely.
I couldn't read TFA (slashdotted?), I skim read the fine paper, but didn't find any reference to this idea. So has someone incorrectly introduced this idea somewhere between the paper and the slashdot summary, or am I missing something?
Quattuor res in hoc mundo sanctae sunt: libri, liberi, libertas et liberalitas.
Darn near killed her!
Where is the news release? http://munews.missouri.edu/news-releases/2011/0516-new-solar-product-captures-up-to-95-percent-of-light-energy/
The newsworthiness is that instead of only 250 million nantennas on one small square like in that INL page, these guys replicated a design onto an "8 inch round silicon wafer" with 10 billion antenna elements. And they did it with high detail and little loss between the "master print" and the copy.
The newsworthiness would HAVE to be in the fabrication and design details. "Optical rectennas" as a form of solar cell have been discussed since AT LEAST the late 1980s (when I heard them described by other people in the L5 society.)
Bantam Dominique roosters crow a four-note song. Once you've heard it as "Happy BIRTHday" you can't NOT hear it that way
This is basically a reprisal of the optical rectenna, and it's already been pointed out that the hardest part isn't rectifying THz radiation, which requires only nanolithiography-sized antennae, but creating the diode fast enough to turn it into DC.
The above link details the status of optical rectennas as of roughly 2002; They managed to get an efficiency of 1% in the near-infrared (100THz) - the diode just didn't exhibit the asymmetry and nonlinearity needed. I'd bet that to make anything happen efficiently at optical speeds, they'll have to somehow create a diode that's based on atomic behavior rather than the bulk electron fluid.
Antennae are for bugs.
Funny you should mention that.
Apparently insects have similar antenna systems in their antennae to detect pheromones by their infrared signature. Also electret excitation structures attached other antenna structures to emit tuned infrared when pumped by grooming.
Here's one reference.
Bantam Dominique roosters crow a four-note song. Once you've heard it as "Happy BIRTHday" you can't NOT hear it that way
Collecting solar energy with antennas - LLL seems to have done this in 2007.
https://inlportal.inl.gov/portal/server.pt?open=514&objID=1269&mode=2&featurestory=DA_101047
I wonder if the non-coherent nature of the sunlight is going to be a problem as each antenna is going to be washed over by a superposition of out-of-phase waves.
Field emission vacuum diodes might get there. I seem to recollect that diamond can have a zero or negative work function.
... is mandatory, and the laws after the first are by no means optional.
He used the idea of using a kind of radio receiver to collect solar energy in several of his short stories, including The Roads Must Roll
http://michaelsmith.id.au
Could they use these miniature antennas to emit light? A 80% efficiency light bulb would be a game-changer.
"Optical rectennas" as a form of solar cell have been discussed since AT LEAST the late 1980s (when I heard them described by other people in the L5 society.
Apparently it was originally proposed in 1972 by Robert Baley.
Here's a link to a 2004 survey of previous work.
Bantam Dominique roosters crow a four-note song. Once you've heard it as "Happy BIRTHday" you can't NOT hear it that way
Invented in 1972: Link to survey of previous work
Make that "proposed in 1972".
As fabrication technologies improved since, various ways to actually do it, or do parts of it (of which this is the latest), have been invented.
This one seems to be a new family of antenna array and interconnect structures without any new work on the underlying rectification mechanism.
Bantam Dominique roosters crow a four-note song. Once you've heard it as "Happy BIRTHday" you can't NOT hear it that way