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New Solar Panel Technology Gaining Momentum
jessiej writes, "Even though copper indium gallium selenide (CIGS), a newer type of solar panel, is less efficient than its silicon counterpart, millions are being invested in manufacturing. From the article: 'CIGS panels use far less raw material than silicon solar panels and the factories themselves cost less to build,' $25 million compared to $230 million in one example. These types of panels could even be made into a t-shirt logo."
A debian logo on your shirt powering a small bewulf cluster of wearable computers computing Pi to many, many decimal places. What a talking point! How will the girls resist!
Think of the Children; Sleep with your Sister
It is. Unfortunatly, to build solar cells you need crystalline silicon. These crystals have to be carefully grown and are quite expensive to produce.
... http://www.howstuffworks.com/solar-cell.htm
There is more info at
- F1 NEWS
From Wikipedia:
Iam not sure about where Wiki got the figure from though.
Wincopy
- The land is already available
- An industry already exists for keeping it cleared
- Roads already extend to most places where people need power
- Electric cars could be charged, and "gas" stations could service them. Same for electric trains.
- Roads would become revenue producing
Make a difference: move to a swing state.
I think they intended those measurements to mean they are capable of manufacturing an aggregate number of solar panels capable of generating X megawatts in total annually. In other words, they're stating the total amount of power output they can output in a year. The confusion arises when the writer attempts to equate the annual output by a CIGS factory (measured in megawatts of power) with the annual output of a coal power plant (measured in megawatt-hours of work). My guess is that they are really stating that a coal power plant can produce 500 MW of power. Of course this indicates a deeper flaw in the discussion in that a coal power plant can continuously produce 500MW of power (presuming a constant supply of coal). Whereas a solar plant can only produce 500MW of power for half the day.
If you deploy too many solar panels in one place you could use up all the sunlight. This has already happened in nothern Scandinavia and during part of the winter they now are in total darkness.
I used to know one of the guys who went to work at Miasolé. He was a sharp guy with a lot of experience in CIGS and related materials.
Slashdot has had a habit of posting the "next big solar breakthrough" which, in the fine print, is not so big yet but will be RSN. CuInGaSe2, on the other hand, has a long track record and previous commercial attempts have produced some solar panels with usable efficiencies (not great, but usable).
CIGS has the advantage of being a direct band gap material, but there are some limits to how far you can push it in efficiency as a single layer device that have not been overcome. One serious advantage is that this material has a fairly wide tolerance on relative elemental composition - different ratios of material in the film will still produce a working cell within a fairly wide range. This is important because industrial process control has tolerances, and wider tolerances mean less expensive production. CuInSe2 and related compositions have some rather interesting electrical properties with respect to defect behavior that allow them to work in this fashion. Anyone with a real interest in this should look at some dense but extremely interesting work by Zunger at NREL.
The biggest problem with CIGS as a production material is probably that it can't "piggyback" on the industry built up for the computer industry. I know that sounds strange, since its lack of reliance on that source of material is also its advantage, but tools to work with CIGS have to be developed more or less from scratch. That's expensive, and the reason that these initial investments are important. The process must be bootstrapped.
CIGS of course doesn't address other problems with solar adoption, such as durability over time, public acceptance and investment, etc. But CIGS is a real material with real potential, and not simply IPO vaporware.
Also of longer term interest is the idea of multijunction solar cells, which use different wavelengths of light on each layer and thus can push efficiencies much higher. Unfortunately they are also an EXTREMELY difficult practical challenge for production. However, there is a lot that can still be done. We REALLY need more funding for solar research in this country, and more basic research in general, but that's another post.
Good luck to the Miasolé team!
"I object to doing things that computers can do." -- Olin Shivers, lispers.org
Yes. Si is the second most abundant element on the surface of the Earth, next to oxygen.
:-)
And that's the crux of the problem too. Silica (SiO2) is abundant (quartz sand), but SiO2 is a BITCH to break apart (the usual reaction is with carbon in an almost 2000 deg C arc furnace), you have to partially melt it or transform it into gaseous silanes (e.g., HSiCl3) to remove impurities, and then you have to grow the Si crystals in high temperature furnaces in very clean conditions. Some of the impurities have to be reduced to the parts per billion range for some applications. It is an energy-intensive and expensive process, and the demand for Si for computer chips cuts into supply for solar cells.
Here's some info on making polycrystalline silicon, and wafer production, including crystal growth. All of that happens before the solar cells or chips get made.
If we lived on a planet without any oxygen, maybe it would be easier
By using a resistor, of course.
Ask me about repetitive DNA
It is not the efficiency (W/m^2) that needs to go UP in order to make fixed solar generation facilities common, it is the cost ( $/W) that needs to come DOWN.
I'll argue that for a typical small house (1500 sq-Ft) there is more than enough roof area to generate all the electricity for the house, even with 6-7% efficient solar panels. Unfortunately, buying current solar panels, this much energy would cost you >$35,000 !! (And that doesn't include batteries, tracker, inverter.... etc)
If these guys can make lower efficiency panels that also have lower cost/Watt, it is a winning situation for everyone. Where do I buy their stock ?
You are partially right... I worked on a project where we were testing a new arc furnace design for smelting silicon (it was a DC furnace as opposed to AC). Wearing one of my hats on that project I wrote a computer model program of the mass and energy balances that took place in the furnace.
My application of the physical chemistry and calculus have passed the haven't used it/lost it point, but if I remember some of the basic things correctly... basically yes it is a real bitch to actually split the silicon (Si) from the oxygen (however, silanes are not involved). It takes a tremendous amount of energy to do so. One of the reasons silica (SiO2) is so abundant is that it is so stable. Being so stable means that it is hard, thermodynamically and every other way, to break it apart. So while Silicon (Si) in the form of Crystaline Silica (SiO2, e.g. quartz, silica sand) is VERY abundant, Si on its own is VERY VERY rare. SiO2 is so much more stable than Si.
-- I ignore anonymous replies to my comments and postings.
I've seen the Miasole production facility and had a chat with the CEO and one of the engineers at the end of the summer. There're a few interesting things that TFA doesn't mention. First, Miasole claims the low $25M price tag for a 200MW factory because they build all of their equipment from scratch. When I was on the floor, they were building a single 25MW line which they turned on for testing last month. That cost them a grand total of $4M (in parts) to build. E.g. they've already done one, so the pricing is reasonably accurate. Subsequent lines will be cheaper. This will give them a huge cost advantage over other similar companies.
Secondly, their production process is cheaper not only because material costs are lower, but also because they use a "reel-to-reel" process in which the semiconductor material is deposited on a sheet of steel which unrolls into the line, and then rolls back up on a reel on the other side. The steel sheets can then be cut and woven into a vinyl enclosure which can be rolled out on your roof like regular roofing shingles. Cool stuff. (They're probably going to attack industrial markets first though...)
Third, the management team comes from the disk drive industry, and built the Seagate facility that is responsible for ~30% of the world's hard drives (could have the percentage slightly wrong, but is in the ballpark). Hard drives use a similar thin film deposition process, and they have built several other manufacturing systems based on thin film processes. This is why the are able to get such a low cost on their equipment: they have the contacts and expertise to build from scratch.
For the record, I have not talked with their competitors, so I don't know the whole story, but Miasole seems very well positioned, and their facility is certainly real.