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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.
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.
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.
Don't be a universal cynic, inform yourself instead. Look up Nanosolar and First Solar on Wikipedia, and you'll see that they have been already mass-producing panels at one-third of the price of crystalline silicon panels for a year or two.
"Nothing happens" is only true if you close your eyes to all the things that actually do happen.
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.
Surprise, there are already companies that are producing thin-film solar panels for less than $1/watt.
The problem is that demand is so high for these inexpensive cells that at least for Nanosolar, you can't even buy them unless you are buying tons and tons of them. That leaves First Solar and those panels get significantly marked up because of the lack of competition at the low end of the market.
That said, wholesale prices of traditional silicon panels are around $3/watt and as an end user you can get them for slightly above that if you shop around.
But once the system is installed you're looking at a minimum of $6/watt currently. So while the panels are still the most expensive part of the system, pretty soon the other components (inverter, mounting hardware, wiring, labor) will exceed the cost of the panels.
We're getting very close to the point where solar systems make financial sense for just about everyone. It already makes sense for any high electricity users who pay a premium for electricity. We'll probably see solar system pricing continue to drop over the next couple years as manufacturing capacity continues to come online.
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.
How plentiful is cadmium relative to silicon?
Worldwide known reserves of Cadmium are about 490,000 metric tons, and production is about 20,000 metric tons/yr. Cadmium is generally recovered as a byproduct from zinc concentrates. Zinc-to-cadmium ratios in typical zinc ores range from 200:1 to 400:1. Estimated world identified resources of cadmium were about 6 million tons, based on identified zinc resources of 1.9 billion tons containing about 0.3% cadmium. The average annual New York dealer price of cadmium metal in 2007 was $7.61 per kilogram ($3.45 per pound).
The source of the silicon is silica in various natural forms, such as quartzite. Silicon is the second most abundant element (after oxygen) in the crust, making up 25.7% of the crust by mass. Word production of silicon is about 5.7 million metric tons/yr. The price for silicon ranges from $0.66 per pound for 75% ferrosilicon and $1.13 per pound for silicon metal.
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
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.