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Nanopillar Solar May Cost 10x Less Than Silicon
Al writes "A team of researchers from the University of California, Berkeley, have developed a new kind of flexible solar cell that could be far cheaper to make than conventional silicon photovoltaics. The cells consist of an array of 500-nanometer-high cadmium sulfide pillars printed on top of an aluminum foil — the material surrounding the pillars absorbs light and releases electrons, while the pillars themselves transport the electrons to an electrical circuit. The closely packed pillars trap light between them, helping the surrounding material absorb more. This means the electrons also have a very short distance to travel through the pillars, so there are fewer chances of their getting trapped at defects and its possible to use low-quality, less expensive materials. '"You won't know the cost until you do this using a roll-to-roll process," says lead researchers Ali Javey. "But if you can do it, the cost could be 10 times less than what's used to make [crystalline] silicon panels."'"
"10x Less"? Is that like "twice as cold"?
for last 5 years same shit gets posted over and over again - Cheap solar panals
5 years later - in some cases panels went up in price
Look at the toxicity of cadmium and all the environmental regulations that come with it. It's regulated to 1/10th the level of mercury in the EU RoHS (Reduction of Hazardous Substances in Electronics) legislation.
"the material surrounding the pillars absorbs light and creates electrons."
Wow, creation Ex Nihilo or from other subatomic particles? That is powerful technology.
Don't tell me. It'll be ready for mass production in 3 to 5 years. Somehow, I seem to remember stories like this from more than five years ago, and still, nothing happens and the solar cells are more or less the same as always.
Rome taught me patience and assiduous application to detail. Virtues which temper the boldness of great, general views.
Once you install these on your roof you will only need to wear your tinfoil hat when you are outdoors.
"A person is smart. People are dumb, panicky dangerous animals and you know it." - K
I've got a nanopillar for you that costs... no wait, that sounded much better in my head. Um, nevermind.
Nanopillar Solar May Cost 10x Less Than Silicon
...and then, it may not.
http://www.geoffreylandis.com
This may have made it cheaper with this innovation, but what if no one wants it because power from coal is cheaper, more reliable, plentiful, and so on? Cap 'n Trade would change the market (not technology) to make this new technology (and others) more competitive in the marketplace. That's the idea anyway.
Just think one day we can grow massive "pillars" in the earth, and these "pillars" can sequester carbon and be powered by the sun as they grow. Then as they reach a certain height and are no longer as efficient as they once were, we can take them down and use them as fuel. We can then plant new pillars to grow and use the by products from old burnt "pillars" to help the new ones grow. Perhaps then if we properly manage these "pillar farms" and modify the "pillars" just right we can have them absorb more carbon from the air than they release when burned for fuel.
If it really was that good, then why would they talk about it after they prove the concept first...
You're absolutely right. From now on, all scientific research should be kept completely confidential until they have developed a product that is ready to ship. After all, there's no value to scientific knowledge; the only things worth talking about are consumer products.
Stupid git.
I don't care if it's 90,000 hectares. That lake was not my doing.
Just think one day we can grow massive "pillars" in the earth, and these "pillars" can sequester carbon and be powered by the sun as they grow. Then as they reach a certain height and are no longer as efficient as they once were, we can take them down and use them as fuel. We can then plant new pillars to grow and use the by products from old burnt "pillars" to help the new ones grow. Perhaps then if we properly manage these "pillar farms" and modify the "pillars" just right we can have them absorb more carbon from the air than they release when burned for fuel.
Perhaps, but is that technology "green"?
Thats right folks - for every time you see the words "May", "Might Somday", "Could eventually", you get to cover a number.
Bonus if you get to catch one or more instances of "In 5 years", "with continued funding", or "commercial quantities"
It seems the only people making flexibles these days are also selling them for a huge markup, and the technology is a lot less efficient than the monocrystal cells. But at least you can buy it. Today.
I used to actually follow up these articles by contacting the companies involved, and asking when they would be able to sell to me as a consumer. I still cant buy any of their products. Any of them.
Yes, I think they call them trees these days.
How plentiful is cadmium relative to silicon? Not so much, right? Isn't cadmium already pretty much spoken-for in other industrial and consumer electronics applications?
Leave it to engineers not to consider the ugly realities of supply-and-demand economics.
For those with access, here's the actual paper:
Fan, Zhiyong, Haleh Razavi, Jae-won Do, Aimee Moriwaki, Onur Ergen, Yu-Lun Chueh, Paul W. Leu, et al. "Three-dimensional nanopillar-array photovoltaics on low-cost and flexible substrates." Nature Materials advanced online publication (July 5, 2009). http://dx.doi.org/10.1038/nmat2493.
One of the cool things is that this new process results in a flexible photovoltaic. In the paper they show that efficiency is maintained even after repeated bending of the material. Even if the energy collection efficiency is lower than conventional silicon photovoltaics, there are tons of applications for flexible photovoltaics, like having tents coated in the material (both for things like camping, but could also be hugely useful for the military, for temporary tents for disaster relief, and so on...), clothing that generates power, and so on... (Maybe even fanciful things like kites that collect solar and wind power?)
It's not a commercial device yet (and oftentimes these kinds of lab devices just don't scale to mass production that well), but it's an encouraging step towards more robust solar cells, which would aid in the more widespread deployments of solar energy.
There is a massive world-wide technology complex driving the optimization of silicon based manufacturing technology. The amount of capital invested into silicon manufacturing process and tools is measured in tens of billions of dollars per year, if not hundreds of billions. If the conventional process improvements is able to achieve 20-25% cost improvement per year, in five years, the cost of panels based on conventional panels would be down to 25-30% of today's cost. A few hickups in the development of the new technology like yield or reliability issues can easily delay the mass deployment by a few years which will negate all cost benefits. Not to mention the possibility of cadmium prices going up if the volumes are picking up...
And don't forget the cost of capital investment, which is already funded due to other "useful" applications in the silicon case. Most other technologies that tried to compete against silicon lost so far, not because of fundamental technical issues but because of the economics involved.
I am not against developing new innovative technologies to achieve substantial improvements in the solar power area. However, it is best to keep the optimism about new and unproven technologies in control until they reach at least beta production stage...
Not really, surprisingly.
Growing plants for fuel is far, far more destructive and less efficient than just turning the solar energy directly to electricity and operating off of that.
All them years of priest training, taken out by one bounty hunter.
Just think one day we can grow massive "pillars" in the earth, and these "pillars" can sequester carbon and be powered by the sun as they grow. Then as they reach a certain height and are no longer as efficient as they once were, we can take them down and use them as fuel. We can then plant new pillars to grow and use the by products from old burnt "pillars" to help the new ones grow. Perhaps then if we properly manage these "pillar farms" and modify the "pillars" just right we can have them absorb more carbon from the air than they release when burned for fuel.
But then we'd have these "pillars" all over the place and would not be able to see the forest for them.
Kwisatz Haderach
Sell the spice to CHOAM
This Mahdi took Shaddam's Throne
No access here. I'm guessing the "pillars" are little quarter wave antennas, with a diode at the base, vaguely like a crystal radio but operating at light wavelengths instead of radio? A really old idea that has never been built (until now?)
In that case, why are the pillars so long? 500 nm quarter wavelength pillars work best with an optimum wavelength of 2000 nm.
Now, 2000 nm is way off in the invisible infrared.
http://en.wikipedia.org/wiki/Visible_spectrum
I'm guessing in true journalist fashion, they reinterpreted the story to be it works w/ wavelengths of 500 nm (vaguely greenish light) therefore pillar length around 125 nm tall? At least the journalists spelled it silicon instead of silicone...
"Science flies us to the moon. Religion flies us into buildings." - Victor Stenger
The cost of solars cell is low enough that infrastruture costs are a significant portion of the total installed cost. The quoted efficiency, 6%, implies that these cells would take up more area than silicon cells, and structiral support costs are proporional to area (I did see the text about possible doubling of efficiency). Another disadvantage to low efficiency cells is increased thermal loading.
Later in the paper they discuss the light-absorbing properties of these kinds of pillar arrays:
References 13,18 are:
L. Tsakalakos, J. Balch, J. Fronheiser, B. A. Korevaar, O. Sulima and J. Rand "Silicon nanowire solar cells". Appl. Phys. Lett. 91, 233117 (2007). doi 10.1063/1.2821113
Hu, L. and Chen, G. "Analysis of optical absorption in silicon nanowire arrays for photovoltaic applications". Nano Lett. 7, 3249-3252 (2007). doi 10.1021/nl071018b
Quoting from that second paper:
Essentially the nanowire arrays are acting as anti-reflection coatings and allowing the light to instead be absorbed.
For cooling look at evaporative cooling or simply pumping the heat into a local river or ocean... Most of California's cities are sited near the Pacific... Yet air conditioning is the single largest consumer of electricity, by far.
Well, yes, our cities are near the Pacific... but Downtown Los Angeles is some 15-20 miles from the ocean, and the LA River, while it is recovering its riparian habitat these days, is hardly up to taking on any significant amount of waste heat. You're talking about *maybe* being able to cool a few beach hotels this way... and that would probably have a detrimental effect on near-shore habitats.
Don't you wish your girlfriend was a geek like me?
Is it cheaper or not? Make up your mind.
If it's cheaper, it's more competitive. No communist-like government price controls needed.
Depends what you mean by "cheaper." The total costs of existing silicon-based solar panels are FAR lower than the costs of fossil fuel generation. However, the out-of-pocket costs are not, at least not in the short run. Those costs don't take into account the environmental damage of mining/drilling required to collect fossil fuels, the pollution they engender, or the eventual "cost" to society of being dependent on exhaustible resources.
Unfortunately, people (and the corporations that they make) are notoriously bad at accounting for these types of external costs. Cap & trade converts external costs to internal costs, and, unlike command and control regulation, it incentivizes exceeding standards. That way, one company can "go green" and reduce themselves well below the cap, then trade their credits to some other company that has no desire to change what they're doing. It gives people choice, creates competition, and captures external costs.
But I guess some people just HAVE to complain about them pesky humans who want to preserve their habitat. I mean, those environmentalists act like they own the world... or at least are responsible for it.
Don't you wish your girlfriend was a geek like me?
If you don't like cap and trade, then what would you suggest should replace it?
The problem is that even though unregulated free markets are good in many situations, there are some situations where they make things worse, not better. Situations such as the Tragedy of the Commons where individuals are sharing a limited resource. Some argue (correctly, I believe) that the reason free markets fail in these situations is that the cost of depleting the shared resource is not correctly accounted for. IMO the obvious solution is to tax the use of the shared resource in order to give it a realistic cost. But I suspect you would find taxation even more onerous than cap and trade.
So how do you propose we deal with the problem of limited shared resources? We will be facing more and more of these situations as long as we are stuck on this planet and if we simply ignore the problem and give free markets free rein then we will be no better than a bunch of lemmings rushing towards the cliff to their doom.
We don't see the world as it is, we see it as we are.
-- Anais Nin
"Times less" is marketing speak. It is used because "Ten times as efficient!" sounds better than "Uses 1/10th the energy!" It's a backwards way of describing a fraction. Sure it still works, but English would still work if I artedstay alkingtay ikelay isthay.
You can start ridding yourself of the marketing speak that's crept into the language by not using it.
Also, using your metric for validating language, 'I can haz' is now acceptable. 12.6 million results confirm it. http://www.google.com/#hl=en&q=I+can+haz
"When information is power, privacy is freedom" - Jah-Wren Ryel
Not dealing with the limited resources problem == suicide. If you don't want to intelligently deal with survival issues, fine. I have no problem with you taking your own life. But if you want to continue to deplete our limited resources at an insane rate don't be surprised if you run into severe conflicts with those of us who would prefer to have our species continue.
We don't see the world as it is, we see it as we are.
-- Anais Nin
Sure. Ridiculous.
Ridiculous, like covering 40% of your average city with ugly, black, heat-island-creating road tar? (Which, btw, could conceivably eliminate your "ugly solar farm" argument entirely)
You don't realize just how much of a city is parking lot until you see it from the air at low altitudes. Google maps helps, but it's just not close because you don't really get the sense of scale. So it's a double-benefit: Parking lots create power, and by putting solar panels above them, keep your car at a comfortable 80-90 instead of an energy-sapping 140.
I have no problem with your religion until you decide it's reason to deprive others of the truth.
Your selection of links suggests an assumption that such a fuel source needs to be fertilized and irrigated. I think most people recognize at this point that such feedstocks won't be economically attractive, and are looking towards things like algal biodiesel and cellulosic ethanol.
What sort of surplus of fertile farmland with ample rain do you think we have sitting around waiting to be farmed? And even algae biodiesel is dwarfed in terms of vehicle miles per acre by solar + EVs (plus, it's basically hydroponics on a massive scale -- i.e., expensive).
People (generally) don't plug their car into the wall (although that will certainly become more common)
That option was the point of my post.
All them years of priest training, taken out by one bounty hunter.