What is Digg?172 Comments
- MacEnvy, on 02/01/2008, -0/+104The article was very poorly written. Unlike silicon panels, these panels absorb both visible light AND infrared wavelengths.
- Shambla, on 02/01/2008, -2/+66"So while there are electrons pouring out of the nano-antennas when exposed to the sun, there is no way to capture those electrons. But don't worry, those geniuses in Idaho are working on that already."
Uh, why are they still talking then when there's science to be done? - Culero, on 02/01/2008, -2/+42 60% of the time it works, every time.
- wapee, on 02/01/2008, -9/+41I can't figure out how this is supposed to be 80% efficient if it only absorbs infrared light.
- TechyLah, on 02/01/2008, -0/+31You guys are a tough crowd! Yes a higher single frequency wave has more energy than a lower single frequency. We are talking here about swaths of spectrum, though. Say 40% of suns energy is in the visible spectrum, 750 and smaller wavelengths, say through 450 nm. That means that the other 60% (roughly because there is ultraviolet, etc...) falls from 750 through say even 2-3000 nm.
By using an electrical (antenna) method of energy absorption, made up of a whole mixture of nano antenna for different wavelengths, the majority of this 60% energy can be absorbed. Say half of the visible spectrum also gets absorbed and you have your 80%
This is indeed a very clever and unique way to use carbon nano fibers. Clearly productizing includes implementing the capacitor and capillary wiring scheme to get the electrical energy out. That's the next step. This is brilliant, however. If manufacturable for reasonable cost it could revolutionize house solar collecting, backpack based solar chargers, electric vehicle recharging, and perhaps the whole centralized national power grid system.
Enough sun energy falls on your house (and is currently lost) that if you could get 80% of it as electricity, your house could be a net supplier of energy to the grid! A lot of research and development went into this major first step. It amazes me how so many two bit scientists can dismiss it as a bunch of crap for half-baked reasons. A little knowledge is a dangerous thing. - menial, on 02/01/2008, -0/+30To the actual article skipping the blogspam - http://www.inl.gov/featurestories/2007-12-17.shtml
- noahhoward, on 02/01/2008, -0/+23Shmuck? He's a lead researcher for nano-technology at a national lab, who the hell are you?
- sotopheavy, on 02/01/2008, -2/+23The theoretical limit is 50% for photovoltaics. It must use other forms of capturing energy as well if it is even true.
- grodrigu, on 02/01/2008, -6/+27It just needs a flux-capacitor
- PhildoVT, on 02/01/2008, -5/+25actually, it doesn't work at night. it doesn't work at all (can't transmit the energy it collects). Read the WHOLE article next time
- AlbinoRaven, on 02/01/2008, -1/+14One of the comments in article brought up a couple of good points about the use of IR and how it works. While I'm all for a better tool it sounds like it needs some more research to make a marketable product. 80% efficient power production is staggering, I hoping the folks making it get a great package together for the public.
Other wise the rest ot the comments are the usual drivel of how we should be bringing electricity to mud huts so we can sell them tv's, dvd's, phones, computers and washing machines. - nbcaffeine, on 02/01/2008, -1/+13that was the joke. thank you.
- inactive, on 02/01/2008, -1/+13Buried for blogspam.
I would have dugg you up if you had just posted your response. - tinko, on 02/01/2008, -2/+13Lunar Panels!
- Nick22, on 02/01/2008, -2/+12Say it aint so, this particular invention didn't result from large sums of money! Impossible!
- TheMachine1, on 02/01/2008, -0/+9I read that 50% limit before to.
http://www.inl.gov/featurestories/2007-12-17.shtml
"The team estimates individual nanoantennas can absorb close to 80 percent of the available energy"
Absorption does not equal electrically output though.
"At this point, these antennas are good at capturing energy, but they're not very good at converting it," says INL engineer Dale Kotter - inactive, on 02/01/2008, -0/+9There is no such thing as %100 efficient.
- rotten777, on 02/01/2008, -1/+8I'll believe it when its on shelves in stores. Until then, it is just a promise that probably won't be fulfilled (unfortunately).
- TheStooge1, on 02/01/2008, -1/+8Yeah, and heavier than air vehicles will never fly either.
- karmabandit, on 02/02/2008, -0/+7This article was awful, and is really a disservice the real work the scientists did. Just for fun, let's dissect all the crap that's in it.
1) "But suddenly, from nowhere, comes Steven Novack of the Idaho National Laboratories with an inexpensive, foldable solar panel that may turn out to be up to 80% efficient." Nothing comes from nowhere-- science is an incremental process where lots of people take baby steps that slowly amount to things over time. This is no different. Also, the key word here is "may", since the writer has no reason to believe this will ever happen.
2) "The surface of the material is printed with miniscule nano-antennae that capture infra-red radiation, the kind that the sun puts out in abundance, and is even available at night." Yes, the sun puts out infrared radiation (here's the spectrum for those interested: http://nanopedia.case.edu/NWPage.php?page=nano.sun ... ). As you can see from that graph, most of the energy is in visible light, but there is still lots in infrared. Now this is "near-infrared" light (1-2 micron), which is not the infrared available at night from heat (~10 micron). Importantly, you cannot get power from the heat energy of the earth, since this violates thermodynamics, so the fact that this IR light exists at night is useless.
3) "But there is a bit of a hitch: There's currently no way to capture the energy being created." Bingo! There's tons and tons of materials in the world that absorb energy. Big ***** deal. The hard part is getting the energy out efficiently, which this article calls the "hitch". Black paint also absorbs infrared light, surely a solar cell made out of paint is just around the corner, right? Now, their materials are much more likely than paint to be made into a solar cell, but the article has given us no reason why.
4) "By putting a tiny capacitor, or AC/DC converter in the center of every tiny tiny antenna, they think they could make this new kind of solar panel export all that energy it's created without raising the price, or lowering the efficiency too much." *rolls eyes*
People really should learn not to digg crap like this up. There are well written science sites out there that are better than false, sensationalist crap like this. - cannonball, on 02/01/2008, -2/+9you're one of those "glass half-empty" kind of people, aren't you?
- aveyuen, on 02/01/2008, -0/+6I think they mean 80% quantum efficiency (at one wavelength). Stating external quantum efficiency is a good way to promote your results to the media without actually lying (the difference is something that most people, even those with degrees in engineering, do not understand).
- Bikechess, on 02/01/2008, -0/+6Obviously, if we want to use intermittent energy sources (wind/solar) for BASELOAD power, improved storage technologies are needed. Currently, however, peak electricity demand aligns well with peak power production from the sun (during the day when everyone is awake and when ACs are running during the summer). So there is huge potential for PV technology before storage becomes an issue.
- OneLess, on 02/01/2008, -0/+6Then hopefully it will be able to output at 1.21 jiggawatts.
- Linzee82, on 02/01/2008, -0/+6Good thing you're not a scientist.
- drmangrum, on 02/01/2008, -2/+8I really wish they would stop with all these pipe dream articles and report on it when it's FEASIBLE. They aren't certain of the current efficiency rating. They aren't certain how they can capture the energy. In essence they have a a theory. Report back to us when they have a working prototype.
- EricMiIIer, on 07/10/2009, -0/+6"It stings the nostrils, but in a good way."
- Timmmm, on 02/01/2008, -0/+6Solar Cells != Heat Engine
- aveyuen, on 02/01/2008, -0/+5I think the thermodynamic limit for full spectrum power conversion efficiency of a solar cell (one that is a pure blackbody - it absorbs across the entire spectrum) is actually in the 80% neighborhood. See: "The Physics of Solar Cells" by Jenny Nelson, first chapter (maybe second chapter). There is a relatively simple derivation. The stated 50% limit is likely referring to discrete bandgap III-V based multilayer heterostructures, which is obviously limited by absorption in addition to all the usual parameters in solar cell design.
- LetsGoHawks, on 02/01/2008, -0/+5There are a couple potential solutions. A wind farm in Iowa is going to use compressed air stored underground. I heard of a place in Texas(?) that is going to store the energy as heat in underground salt formations, and there was an interesting article about using flywheels, which can be an incredibly efficient (90%) way of storing energy, but of course there are some engineering obstacles to overcome.
- kaelyiesta, on 02/01/2008, -4/+9"there's science to be done"
I got flashbacks of dying at the same spot over and over in Portals when I read that. - FTLJohnson, on 02/01/2008, -0/+5From the Idaho National Laboratory's Website: http://www.inl.gov
Taking antennas to the atomic level
The miniscule circuits absorb energy just like the antenna on your television or in your cell phone. All antennas work by resonance, the same self-reinforcing physical phenomenon that allows a high note to shatter glass. Radio and television antennas must be large because of the wavelength of energy they need to pick up. In theory, making antennas that can absorb electromagnetic radiation closer to what we can see is simple: just engineer a smaller antenna.
An array of nanoantennas, printed in gold and imaged with a scanning electron microscope. The deposited wire is roughly a thousand atoms thick. A flexible panel of interconnected nanoantennas may one day replace heavy, expensive solar panels.
But finding an efficient way to stamp out arrays of atom-scale spirals took a number of years. "It's not that this concept is new," Novack says, "but the boom in nanotechnology is what has really made this possible." The INL team envisions the antennas might one day be produced like foil or plastic wrap on roll-to-roll machinery. So far, they have demonstrated the imprinting process with six-inch circular stamps, each holding more than 10 million antennas.
It wasn't immediately obvious the structures might be used for solar power. At first, the researchers considered pairing the antennas with conventional solar cells to make them more efficient. "Then we thought to start from scratch," Novack says. "We realized we could make the antennas into their own energy harvesters." - LetsGoHawks, on 02/01/2008, -0/+4A lot of energy is lost in the coversion of electric to hydrogen and back to electric. It's really not a very good method. Plus your dealing iwth a highly flammable compressed gas.... I'm not sure the general public can be trusted with monitoring and maintaing a machine that produces and stores a highly flammable compressed gas.
- Elliuotatar, on 02/01/2008, -0/+4When I look up there, it makes me glad I'm not you!
- forcedfx, on 02/01/2008, -1/+5But an AC/DC converter converts AC power to DC power. An inverter would convert the DC to AC.
- FTLJohnson, on 02/01/2008, -1/+5Soon, they'll have to change the state mascot to be a potato wrapped in gold foil baking from the power of the sun flowing into his all seeing eyes... SUPER SPUD... with his long flowing golden cape of justice (that also happens to be a solar cell) Huzzah!
- skankme, on 02/01/2008, -1/+5for the people that are
still alive - Bikechess, on 02/01/2008, -0/+4Current PV panels require ~1-2 years to 'payback' their energy cost for production and installation. They last for 20 years... The energy payback problem was true during the infancy of this technology, but the industry has grown up since then.
- FTLJohnson, on 02/01/2008, -0/+3People need to LINK Solar and Hydrogen together in their brains more often... I consider Hydrogen to be like a great battery. Hook up a bunch of solar cells to a tank of water and electrolytes... and poof, you've got a large output of storable fuel ready to be consumed at any time... Including at night when these cells would be outputting less...
Say these only work as well as regular solar cells... if they are cheaper to produce... We can start getting people off the grid NOW. The Grid needs to be decentralized...
Also, if cars have solar cells on their roofs... and generate hydrogen all day... Imagine the surface area of solar cells across every parking lot in the world... all generating and storing energy, rather than consuming it. The cars could be used to even add power to your house... - Jebral, on 02/02/2008, -0/+3He said approach, not achieve. Still, you're right.
- GreyICE, on 02/01/2008, -0/+3Yeah, breakthroughs tend to work like that. As opposed to innovation that takes millions upon millions.
Basically all those million dollars approached it from one angle (Photoelectric effect). This takes a completely different tack. The same way transistors (the work of a little-known physicist) rendered the millions spent in expensive vacuum tube research a complete waste. - azzy, on 02/02/2008, -0/+3Jiggawhat?
- davidrools, on 02/01/2008, -1/+4it's a different ballgame with things on the nano scale. but there will have to be a big drop in efficiency when energy comes from the nano-antennae to a usable power source. then things will probably drop closer to 40-50% efficiency.
but when it comes to solar power, thermodynamic efficiency is essentially meaningless except when comparing technologies for technology's sake. It comes down to PRICE per WATT. If it's cheaper to buy and operate five 10% efficient solar panels than a single 50% efficient panel, you'll go with the five lower efficiency ones. - BaDooer, on 02/01/2008, -3/+6Energy from the sun!?! What will hippies think of next. JK...This is Awesome.
- ThndrShk2k, on 02/01/2008, -1/+4One catch: They can't capture the electrons from the design.
- enivid, on 02/01/2008, -0/+3I think the real question would be to ask: Can 1 unit produce more energy during its lifecycle than during its construction/transportation/installation/disposal?
- BryanTheCrow, on 02/01/2008, -0/+3How much will they cost to manufacture?
- cannonball, on 02/01/2008, -0/+3A diode and capacitor is probably too inefficient for converting. I'm guessing they will need some kind of nano-converter.
- inactive, on 02/01/2008, -0/+3Actually most of it is reflected off your skin. More so considering the pale monitor tan your average Digg user has.
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