Slashdot Mirror
Cheap Paint-able Solar Cells Developed
Invisible Pink Unicorn writes "Researchers at New Jersey Institute of Technology have developed an inexpensive solar cell that can be painted or printed on flexible plastic sheets. According to the lead researcher, "Someday homeowners will even be able to print sheets of these solar cells with inexpensive home-based inkjet printers. Consumers can then slap the finished product on a wall, roof or billboard to create their own power stations." The team combined carbon nanotubes with tiny carbon buckyballs (fullerenes) to form snake-like structures. Add sunlight to excite the polymers, and the buckyballs will grab the electrons. The article abstract is available through the Journal of Materials Chemistry, with an illustration of the technology."
It will take a drop in price before solar panels finally hit the big time. But boy, when they do drop expect an explosion of uses.
See my journal for slashdot ID's by year. Mine created in 2005. http://slashdot.org/journal/289875/slashdot-ids-by-year
I knew that they would come up with cheap paintable solar cells. I'll pick them up in my flying car.
Take the cheese to sickbay, the doctor should see it as soon as possible - B'Elanna Torres, "Learning Curve"
are you going to do the right thing?
I suppose. It's so strange these days. You see people doing research, then posing for a photo and making a press release. Then.. nothing. The promises and predictions don't amount to actual products that people can buy. But I suppose they do get you more grant money.
How we know is more important than what we know.
It's time to surpass the nudists, green energy compliance, and all other consortiums. We shall paint our bodies with solar cells as we jog through the desert! Body painting party, anyone?
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Hmm, I wonder if I can paint my car with this and tell big oil to !$#@ off? Alternate fuel sorces anyone?
Are they paint-able in the same way that clothes are wear-able?
Hopefully this will make our tanks, planes and kill-bots better by reducing the mass/volume required for energy storage, thus increasing the space available for bullets, nukes and sharp sticks.
All those graffiti artists must be going nuts waiting for this to come out in spray cans.
"Someday homeowners will even be able to print sheets of these solar cells with inexpensive home-based inkjet printers."
"The team combined carbon nanotubes with tiny carbon buckyballs (fullerenes)
Whooboy! I wonder what that print cartridge is going to cost!
Dupe http://science.slashdot.org/article.pl?sid=05/01/1 0/1832253&tid=126
I'm going to hold out on commenting until Unicorn confirms that the story is legit and that he isn't going to post a retraction.
This reminds me of.... 2002.... http://www.berkeley.edu/news/media/releases/2002/0 3/28_solar.htmlsame idea, 2002
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Does it seem to anyone else like carbon nanotubes are modern snake oil? Seriously, is there anything they CAN'T do?
GreyPoopon
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Why is it I can write insightful comments but can't come up with a clever signature?
Steorn, paintable solar panels, fucking concurrent c++ compilers, walking robots. It's bullshit - never does this come to market. Like the rest, it will evaporate and take the energy with it. A good time for these stories is when they're available for purchase. I can't believe I'm saying this, but, it would be more gratifying to see an *advertisement* for solar paint, than this.
"Someday, I hope to see this process become an inexpensive energy alternative for households around the world."
Someday indeed.
I for one welcome our new inexpensive solar cells that can be painted or printed on flexible plastic sheets overlords.
What is conspicuously missing from that article is any kind of a figure for the conversion efficiency of the devices they're making. Lots of researchers have been working on fullerines. What efficiency are they achieving? 5 percent? 1 percent? A tenth of a percent? Lacking any kind of number for efficiency-- preferably an efficiency measurement verified by the National Renewable Energy Laboratory-- tends to make me think that this is theory with no actual devices manufactured at all.
http://www.geoffreylandis.com
I'm feeling bummed out. I've been reading story after story of cool-sounding research that never seems to hit the market. Anyone wanna bet when I can go out to wal-mart and get something like this? I'm not holding my breath.
The problem with the article is that it uses the words "have developed" as in "have developed an inexpensive solar cell that can be painted or printed on flexible plastic sheets" when in reality it sounds more like "have an idea for" or "have developed a concept for" pending the advancement of material science. I seems they haven't built or tested..I mean painted a prototype, so the article is getting ahead of itself a bit maybe.
Has some good new ideas on solar technologies, green architecture and info on paint like options in the USA. http://www.pbs.org/wgbh/nova/solar/
Domestic spying is now "Benign Information Gathering"
First, the article is the NJIT press release, with essentially the same text and pictures.
Second, this is yet another of those overhyped "minor advance in materials science" articles. The abstract for the technical article says only "The results indicate that C60 decorated SWCNTs are promising additives for performance enhancement of polymer photovoltaic cells." There's no mention of "paintable solar cells".
"Paintable solar cells" have been talked up before (they were mentioned on Slashdot two years ago) but nobody has actually made that work. There's this fantasy that you somehow spray something on your roof and get power out. But it's not likely to work.
Some guy at the University of Toronto has been hping this for several years now. He got quite a bit of press in 2005. But his actual cells were, according to Business Week, 3 orders of magnitude worse than existing technology, were more expensive to make, and had a limited lifetime.
I was much more impressed when I went to a talk by Mark Pinto, the VP of Applied Materials' solar unit. He spoke for an hour and a half, and never mentioned "eco" or "green". He's a manufacturing exec, and he sees this as a manufacturing cost problem. They know what to do; they just need to do it bigger, faster, and cheaper. Which is what Applied Materials does, very successfully, for ICs and flat panel displays. He has charts showing that in high-sun areas like southern Spain, solar power can now be cheaper than existing electricity sources. So they're building a big solar panel plant there. As the materials improve, they'll convert to new materials and processes, just like they do for ICs. And as with ICs and flat panel displays, they expect to follow the cost curve down.
Their existing generation of solar panel fab is derived from their flat panel display fab equipment, but they expect that, over time, those technologies will diverge. They'd like a roll-to-roll solar cell process, and bought a company with one that sort of works, but if it doesn't, they think they can do OK with something that works like a huge wafer fab, with each wafer covering five square meters.
One thing I've always been curious about (and it may seem obvious, though I don't know), is whether or not we could subsist off solar energy, if we could use it efficiently. Answer: oh yeah! (easily)
From wikipedia
4.26×10^20 J, the yearly energy consumption of the world as of 2001
5.5×10^ 24 J, the total energy from the Sun that strikes the face of the Earth each year
We only use about 1/10000 of the total solar energy (as of 2001).
Rhymes that keep their secrets will unfold behind the clouds.There upon the rainbow is the answer to a neverending story
Carbon nanotubes are cited in the article as having excellent electron transport properties. In organic photovoltaic devices, charge separation and efficient electron (and hole) transport are desirable properties. Perhaps if the nanotubes do have these properties then the researchers should investigate them?
So, once you paint your house or car with these nanotube-based organic solar cells, how do you get the electrons they produce into your car's electric motor or your home's appliances? In order to use the energy produced by paint-on solar cells, you need a surface that will conduct the electricity to a battery, motor, or conventional wiring. Your house, for example, would have to be paneled with circuit boards or some sort of wire mesh and then painted with the solar cells.
Glad to see photovoltaics doing well, while this is a welcome advancement. I'd personally love to see more juice per square CM of solar cells. So instead of painting my house with cells just to power my TV, I'd rather have a dense 1 foot square solar cell powerful enough to power my TV and computer.
Inexpensive photovoltaics should be renamed "Someday Technology", since every article written about solar seems to use the word "someday" in it somewhere.
I'm sick of seeing another "cheap solar cells!" article with no substance. The editors should stop approving these types of stories until they get an article that includes purchasing information.
According to all of these technological innovations I've been reading about for the past few years I should be printing blow-up dolls, replacement organs, a hot cup of coffee, and now solar cells... all from my home printer.
Sheesh!
Electric lighting is much more efficient in terms of lumens per BTU than a candle or kerosene lamp, so one would think that people who get electricity and electric lighting to replace their candles and lamps reduce their energy usage. In fact, what happens is that their usage goes up by an order of magnitude. When folks in third world countries use candles and oil lamps, they maximize their use of sunlight, only use light sources when necessary and often for task lighting, take advantage of full moons, and watch consumption closely. With electricity, they use bright area lights for task work, leave lights on in adjacent (or even unoccupied) rooms, and other things unimaginable to them just months before.
The reverse case, living on a battery bank and solar panel, follows a similar pattern. When living on battery, tracking your power levels becomes second nature. You become much more aware of what you are using and start to make trade-offs in your mind: do I really want to watch that movie and draw down the battery bank when I could just as easily read a book (or go to bed at dark and get up earlier, or actually talk to my wife, or...) It is not a matter of suffering or 'making do', but just finding you don't need as much as you thought you did. In the summer when the battery banks are overflowing, you splurge, like running the ice cream maker.
Having gone back and forth between these worlds a few times, I am very aware of the power I expend. Right now, my wife and I have one light bulb (a CFL) on in the entire house. There have been times and places that even burning a single light this long after dark would have been unusual.
So, yes, solar panels can provide enough power to run your life, particularly if you make the logical adjustments to living with a variable and finite source of power. We get so used to flipping a switch and not thinking about where the power comes from, that we expect the exact same out of renewable power sources. It also means that we are horrible at dealing with emergencies or changes of fortune. But we don't have to live that way.
This discovery builds on experiments using fullerenes and their derivatives as electron acceptors for organic semiconductors like polythiophene, and the use of a carbon nanotube a a molecular wire to cart away electrons may indeed represent significant improvement over the acceptors currently in use- not likely enough to bring it in range of good silicon photovoltaics, but since I can't read the full text of that article, I can't say for sure. The problem I see with this particular new idea is that in comparison to the organic photovolts out there now, it more than likely would strike a poor balance between increased performance and increased price- high purity single walled nanotubes are still in the hundreds of dollars per gram range, after all.
"FDA staff reviewers expressed concern about the number of patients who were left out of the study because they died."
This recent article mentions the efficiency factor is getting better and it has tried this method out:
http://www.technologyreview.com/Energy/19044/
Unlike the theoretical method mentioned by slash dot.
Disclaimer: I am a graduate of UCSB so I am biased.
i don't know how.. but some how greenie assholes will find a way to blame this failure on bush and the oil companys.
If you mod me down, I will become more powerful than you can imagine....
What are the specs for this material? How many W per m^2 can the paint generate under the 1KW:m^2 of "solar noon"? How many joules does it take to manufacture the coatings, how many joules to apply them from, say, a big "inkjet" printer? How long do they last?
Therefore, what is the total energy budget of this material?
If they have to be replaced frequently, produce low wattage, and cost a lot of energy to produce and deploy, then silicon PV cells that last 35+ years at 15-25% efficiency might still be better, even though the silicon cells cost a lot of energy to produce, deploy, maintain and recycle. Or maybe this tech is better.
I wish every journalist covering the accelerating solar power industry would always answer those basic questions. Otherwise, it's just science fiction dressed up as propaganda.
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make install -not war
The paper answers some of the questions that others have posed in this thread, particularly about the efficiency of the process achieved so far (0.57%). These are their conclusions:
It's clearly at a very early stage of research/development, but polymer photovoltaic cells have such enormous potential that it's an extremely valuable direction to pursue.
"The question of whether machines can think is no more interesting than [] whether submarines can swim" - Dijkstra
Most single storey houses have enough roof space to allow current silicon panels to both power the house (under net metering) and charge a plug-in hybrid. It does not take acres. If you have a taller house, you might need some yard space since you've got more floor per unit roof to power. Polymer panels may hit 10% efficiency befor to long. The current record is 6.5%http://www.technologyreview.com/Energy/19044/, so there is not all that far to go to catch up with
16-20% efficient silicon.s -selling-solar.html
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While this sounds cool, this seems to be yet another technology that we'll eventually be able to print with our inexpensive inkjet printers.
hopefully they'll release the "nanotube buckyball solar panel" cartridge to fit in the same printer as the OLED display cartridge... etc.
Can't wait to read some word documents written using solar panel nanotube ink, too.
"Someday homeowners will even be able to print sheets of these solar cells with inexpensive home-based inkjet printers." The printers themselves may be inexpensive but you can bet your last dollar the printer cartridge cost will need a NASA style budget!
What's more, much of the energy we consume is wasted because we use heat engines to convert it to more useful forms. So, using photovoltaics, we skip that step http://mdsolar.blogspot.com/2007/04/green-numbers. html so things actually look even better than your calculation suggests.
s -selling-solar.html
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Woo! For some reason when developments like this come out of a school you attend, a wave of pride just comes over you. They actually have an impressive solar array on top of the Student Center with a little terminal that reads out the power production. It's pretty nifty. I believe it's the biggest array in New Jersey. I'm glad they are making progress. Now all they need to do is develop a way for girls to attend the school.
622677120
And then those danm hippies will say we're overusing the Sun's light.
I'm not a republican, I'm just joking.
When you see this type of logic and it is meant, it's very revealing that they aren't listening to what you say, only what you sound like when you say it. "If you want me to do X, and I do X, you'll just say I should be doing Y because you complain and complain and that's all you do- I have therefore categorized you as an idiot or [member of disliked group] and so anything you say about X must not be true." Anyone who brings it up is automatically an idiot whose opinions can be disregarded. Similar thinking: "If you think X is a problem, you shouldn't be talking about it unless it has affected you personally, otherwise you've either got no idea whether X is really a problem, or you have an ulterior motive and secretly want to make it worse." If the person is affected by X, then aha, that's why. People who think like this drive me crazy. And there are so many of them. They especially fall for "bias"-type arguments. There is no messenger you cannot impeach with an attitude like that, and by impeaching the right messengers you're free to construct any sort of alternate paper-thin reality you want that can exclude any X you choose.
So if this takes off and ends up confusing the bees or something, I think they're pretty much screwed.
These guys should make a hydrophobic liquid that can be poured on top of a large water surface, like a swimming pool, and turn it into a big solar cell. That way you could just pour it on your pool to get a few kilowatts of free power and during an energy crisis we can just go to a large body of water and pour a big photovoltaic slick across the water. Yee hah wouldn't that piss off the hippies! Of course the drawback here is obvious: no swimming pool when the A/C is on.
"Someday homeowners will even be able to print sheets of these solar cells with inexpensive home-based inkjet printers."
No, they won't. As there's no real money to be made from free energy in this sense compared to the real energy industry, this discovery won't hit the store shelves. Ever. Just like anything else that benefits us as humans rather than our wallets. It's plain business to fight anything that can drop your revenue, and free energy in this sense is an enemy to the energy industry in the same sense that a true hydrogen car is an enemy to the oil industry.
In addition to painting these on...I would bet you'd also need to wire it into your house.
Upconvert the voltage. Change to AC. Find some way to store it or pipe it back into the grid.
All non-trivial stuff.
I think I read somewhere once that bucky balls were environmentally hazardous because they are hard to contain, don't break down, and tend to do things like get lodged in blood vessels and insect spiracles.
If so painting your house with this stuff would not be a good thing.
Is this correct at all? And if so, how significant is this danger?
Why is it that every SlashDot article having to do with technology includes the phrase "Nano-Tube", "Quantum", or "Bucky-Ball"?
Has anyone else noticed this?
A goal is a dream with a deadline
Buckyballs trap electrons, although they can't make electrons flow. Add sunlight to excite the polymers, and the buckyballs will grab the electrons. Nanotubes, behaving like copper wires, will then be able to make the electrons or current flow.
My GOD!...it's to simple!...Why didn't I think of that!
Seriously, can somebody point me to someting a little more detailed? That article sounds a little "vapor-ish". On the other hand, if such a thing will be coming to market, I'd like to know where I could buy it.
A goal is a dream with a deadline
On a sunny day, at noon, you get roughly 1KW per square meter.
I don't know if this agrees with what you said.
1 ft * 12 inches/foot * 0.0254 meters/inch = 0.3048 meters 0.3048 * 0.3048 = 0.0929 square meters 0.0929 * 1000 = 92.9 W I'd say the two numbers agree fairly well with one another.
<soapbox>My relatively new pet peeve is when people use the word "monkey" to mean "ape". That link you provide keeps talking about monkeys while showing pictures of apes (e.g., chimpanzees and orangutans). They even call us monkeys. We're apes, not monkeys. Both apes and monkeys (as well as lemurs) are primates, but apes are not monkeys any more than humans are orangutans.
Next on my list: to get them to call it the "Scopes Ape Trial". :)</soapbox>
Ben Hocking
Need a professional organizer?
Just to elaborate (for those not in the know), the objective of phase III of SBIR grants is "for the small business concern to pursue with non-SBIR/STTR funds the commercialization objectives resulting from the Phase I/II R/R&D activities." (emphasis mine)
Ben Hocking
Need a professional organizer?
(any argument that says (someone is stupid and shouldn't be listened to) is stupid and shouldn't be listened to)
That said, I do disagree with this statement, as it suggests that every time the "boy cries wolf", you should go check to see if there's actually a wolf. There are certain sites (e.g., junkscience.com) that I no longer bother trying to understand articles from because every time I have, it's turned out to be a waste of my time.
Ben Hocking
Need a professional organizer?
Who wrote that press release? A media undergrad? Look at this wonderful statement:
"Expensive, large-scale infrastructures such as wind mills or dams are necessary to drive renewable energy sources, such as wind or hydroelectric power plants."
Gee, really? I always thought we made windmills for hydroelectric power. Or how about this:
"When sunlight falls on an organic solar cell, the energy generates positive and negative charges. If the charges can be separated and sent to different electrodes, then a current flows. If not, the energy is wasted."
Ummm, ok, and where do you explain how these cells cause charge separation? Nowhere? Oh, ok. My fav though, is this one:
"carbon nanotubes complex, which by the way, is a molecular configuration of carbon in a cylindrical shape"
Carbon tubes are tubes of carbon? Wow! Thanks, Mr. Simply Pretends to Understand Anything with More Than One Sylable and Writes About It Anyway.
Maury
I work for a solar research company (private enterprise, for profit, looking to make solar as cheap as possible) and one thing that strikes me about this sort of news is that if it were true we could buy it already. The fact is that the solar market is enormous already, never mind how big it will get once the price comes down (and the price is coming down), so if someone had a technology that was even marginally cheaper than the current state of the art, that brought the price down even a little, then there are very few barriers to get that thing to the market. So when and article appears on slashdot which promises to change the world of solar energy, you can know that it is genuine if they are backing a product for sale. Because if they had a technology that worked VCs would be knocking down their doors. Otherwise, it's dismissible, for now.
It appears there is a misprint in this article. You cannot (as far as I know) collect electrons from the sun. You can however make a material that absorbs the suns PHOTONS. In Si (silicon) solar cells, certain photos from the sun are absorbed by an electron in the material. The photo transfers it's energy to the electron and the electron jump up to a higher band (think of the bands as rungs on a ladder). When the electron leaves the lower band it creates a hole where it used to be (a space for another electron to fill). If the electron is left in the solar cell, then it will spontaneously jump back down to a lower band, and emit another photon. The trick is to suck the electron out of the solar cell, and force it to run through an external circuit (your house). Hope this helps, KiWiCaNuCk
The best I can find is "bumper sticker wisdom", but I suspect it predates bumper stickers. I suspect, although I'm loathe to attribute anything good to him, that it might have been originated by that poster "Anonymous Coward". (I have yet to actually figure him out. Sometimes he seems like a bleeding-heart liberal, and yet at other times he comes off as a cold-hearted conservative.)
Ben Hocking
Need a professional organizer?
...you have { efficient, small, affordable } pick 2. It is easy to make a breakthrough in one of them if you ignore the other two. It is somewhat harder to make a breakthrough in 2 while ignoring one, and any article that doesn't mention all 3 when talking about a breakthrough is almost certainly hype.
I painted my solar cells, and now they aren't working as well. I demand a refund.
Evolution will get over it in a couple of generations, don't worry about it.
And on the plus side, it'll drastically reduce the problem of funding social security for the stupid baby boomers.
"Who is the Journal of Quantum Physics going to believe?" --Stephen Hawking
If it works, that is. If it doesn't, won't matter anyway. File this with the 80mpg carburetor and the Ark of the Covenant.
They say the first thing to go is your penis. Well, it's either that or your brain. I forget which...
Yeah, but, the replacement cartridge costs are astronomical!
"It's the height of ridiculousness to say for those 9 lines you get hundreds of millions."
I'm not a homeowner, although I am looking to be one in the next year or so. I would like to do solar paneling on the home I do end up in, and I'm wondering, has anyone done this and gotten a solid price range on what it will cost? I see figures thrown on here and there, but none really state what it is for in terms of panel size, average electricity generated, etc.
Librarian: Oook!
Justice is the sheep getting arrested while an impartial judge declares the vote void.
Aten Solar just reduced their price to $3.00/peak Watt. These are lower efficiency panels so you'd want some yard space: http://www.ecobusinesslinks.com/solar_panels.htm. s -selling-solar.html
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and then the public will lose all faith in science that they have left.
When scientists, as you say, scramble to win the public over, then fail again to deliver what the article worded not as interesting trivia but as a promise of a brighter future, they hurt their own credibility.
Here's an example of what we've been told should be possible by now: Here, take my flying car over to the wristwatch computer store and ave the robotic sales assistant help you pick out a model with a 4x8' screen projector on it that will last 20 years and be powered by a hydrogen fuel cell. Then hop on a commercial charter to Mars and deliver it to me in my office atop Olympus Mons.
Now, obviously, it's sometimes understandable to be overly optimistic about research, but when people consistently over-promise and under-deliver, you lose faith in them. Call it the Popular Science effect, if you like.
Actually, solar energy *is* nuclear since stars are big fusion reactors. :)
If you want to get all fancy about it, geothermal is nuclear too - radioisotopes keep the planet's core hot.
My God, it's Full of Source!
OUTSIDE_IP=$(dig +short my.ip @outsideip.net)
What would be really elegant is painting roads to collect solar power for cars. There is a whole lot of road out there!
Paving with solar cells would collect power from the sun that hits the roads. (Using solar panel sunshades would eliminate wear problems.) More power could be had by paving the median, pull-over lanes, and surrounding veggie area, to collect the sunpower that hits it. Yet you're still pretty light for powering the traffic.
But putting a row of windmills down the median could collect power from the sunlight hitting a FAR larger area. Windfarms the size of the interstate highway system would be in the right ballpark to power the traffic with a big surplus. Enough to make a big dent in powering the cars and trucks that are on the minor roads and the infrastructure they're commuting to/from.
Bantam Dominique roosters crow a four-note song. Once you've heard it as "Happy BIRTHday" you can't NOT hear it that way
We prefer our roads to have a coefficient of friction greater than that of paint. And as the paint wears, it would end up in the water.
On the other hand, there's also a lot of roofs and parking decks. Parking decks and WalMart-type buildings have found that the shade provided by solar cells is a substantial side-benefit, whether to shade cars or to reduce the building's cooling costs.
...they shorted out on the metal roof and the house burned down. Who do I sue?
Have gnu, will travel.
The high energy-conversion efficiency of the thin-film cells and the high throughput of the process make Ovshinsky's photovoltaic cells a revolutionary leap forward for solar energy. They have been installed at various sites around and above the globe, from Mexican mountain villages to the Mir space station. Ovshinsky's "Uni-Solar" roofing tiles, for residential buildings, have won Popular Science's "Best of What's New" Grand Award (1996) and Discover Magazine's Discover Award in the Environment category (1997). I keep wondering what the hell happens to the technology breakthroughs that I have been reading about since high school. Back then it was amorphous semiconductors, now apparently it's carbon nanotubes. It's fun stuff to read about on Slashdot, but will it ever be mass produced so people can actually use it?
because we only have 6.5 billion years of proper sunlight left.
Somewhere between a super nerd and a rock star...
Notice the energy conversion efficiency is 0.57% and the fabrication process is quite sophisticated, requirng exotic Fullerene chemicals and other sonatic lab gear.
Compare that to a classic Dye-sensitized cell one can make at home with titanium dioxide and rasberry juice... but delivers 0.45% energy efficiency.
The DIY solar cell recipe below achieves nano-level self-assembly with TiO2 instead of bucky balls and outputs 0.43 V and 1 mA/cm2. Titanium Dioxide is very inexpensive because it's most common ingredient used in white pigment. http://www.solideas.com/solrcell/english.html
How useful is this much power? Consider that a cheap Nokia phone requires 3.7 volts at 140, which equates to 0.518 watts of power needed to charge it. That means one of the cells above,no larger than a square foot, could do the job... on a sunny day. http://www.knowprose.com/node/8906
Interesting note that a 14 year old girl won a Discovery Channel Science Award testing one of these home-made TiO2 cells. http://school.discovery.com/sciencefaircentral/dys c/finalists/profiles/kumar_asmita.html
solar battery chargers are already here:)
http://www.steves-digicams.com/icp_solar.html
good for keeping your batteries on charge or topped up:)