Silicon vs. CIGS in solar
CNET’s News.com has this informative piece that discusses the difference between silicon and CIGS (copper indium gallium selenide) in the production of solar PV cells. Most solar cells today are based on silicon, but a number of startups entering the market — NanoSolar, HelioVolt, and Miasole, to name a few — believe CIGS-based thin film cells are cheaper to make, easier to install and will catch up to silicon in terms of efficiency. Silicon has an edge right now because you can leverage existing research and a trillion-dollar infrastructure built around it, but there’s also a shortage of solar-grade silicon so this is limiting growth. Is CIGS the answer? Or will silicon continue to reign supreme?
Tyler Hamilton is editor-in-chief of Corporate Knights magazine and a business columnist for the Toronto Star, Canada's largest daily newspaper. In addition to this Clean Break blog, Tyler writes a weekly column of the same name that discusses trends, happenings and innovators in the clean technology and green energy market. This blog is a personal project started in April 2005. It is not an official blog of the newspaper.
October 3rd, 2006 at 7:25 am
BTW, I think that should be CIGS, not SIGS.
Anyway, I find it funny how in the last 12 months the US commentators are suddenly waking up to how “hot” PV solar is and focusing on for example Nanosolar and Miasole are the leaders. Uhh, this maybe has something to do with PR and the strings pulled by their new venture capital backers, because none of these companies are anywhere on the global scale. Germany alone deploys EIGHT times more PV per annum than the US.
Lastly, for all the talk of a 430 MWp plant, I have yet to see a peer-reviewed or internationally certified test of a normal production (not lab) module from Nanosolar. I think they’re printing 4% efficiency VC paper…
October 3rd, 2006 at 9:26 am
On the SIGS thing… oops! Sometime brain and fingers don’t cooperate. Thanks.
October 3rd, 2006 at 1:10 pm
The largest supplier of CIGS cells, Daystar Technologies, was not mentioned. They are currently shipping commercial quantities of CIGS cells. They have achieved 15.7 percent efficiency off of a pilot production line and expect to achieve 10% off a 10MW commercial production line by the end of the year and which they fully expect to eventually bring up to 15+%. They are planning to have production methods that are directly scalable to a gigawatt capacity demonstrated by 2008.
They have developed a roll to roll sputtering production process, which may not be as efficient a process as those proposed by Maisole and Nanosolar, but they still project costs that are in the $1/Wp range on the system level which is competitive with coal fired power plants.
Maisole and Nanosolar have also announced that they will have large scale production facilities in the same time frame, but I have not seen any public information as to what basis they are using for these plants. Their advantage is that they can “print” their cells on a non-metallic substrate, while Daystar requires a matellic substrate for their sputtering process.
Thin-film silicon technology, which uses much less silicon than conventional silicon cells, is also progressing rapidly and greatly minimizes the silicon supply problem. Sharp is projecting costs similar to that of Daystar by 2010. Silicon supply issues should be under control within 2 years.
What technology has the least cost and becomes the dominate supplier to me is rather mute-the prospects for low cost gigawatt supplies of PV solar (from one manufacturer) by 2012-2015 seems to be a fair bet. The real question is when will we have enough production to meet the demand for solar cells.
October 5th, 2006 at 1:06 am
http://www.photon-magazine.com/news_archiv/details.aspx?cat=News_PI&sub=worldwide&pub=4&parent=459
“But the question remains: are these alternatives just a short-term solution approach? The silicon crisis will end in a few years – if not through thinner wafers and other means of saving material, then with additional production capacities. Actually, the problem isn‘t one of a lack of raw materials – nearly 15 percent of the entire earth is made of silicon. However, while there are only vague estimates about the amount of indium, tellurium, and gallium, one thing is certain: their availability is more or less limited. “