Thin-films are being called 2nd generation solar PV cells, and it is a tradition nowadays to classify them by virtue of differences in the technologies involved in their manufacturing.  We will presently have a look at the 3 currently popular types of Thin-Film

1. The first to be established, selling under the brand of Uni-Solar, was amorphous silicon, pioneered by United Solar Ovonics.

This technique, now used by a few dozen manufacturers around the world, relies on a small amount of amorphous silicon alloy and accounts for about 60% of the thin film PVs made today. These systems have been sold for several years as building-integrated PV offering the advantage of nearly undetectable systems on rooftops for both commercial and residential buildings. United Solar sales amounted to 73 megawatts in 2008 and their sales pipeline is $1.8 billion.
India’s Moser Baer, on whom we had another blog yesterday,  seems like a potential challenge for the world’s Thin-Film manufacturers.

XsunX, (XSNX.OB) is also manufacturing thin-film modules using amorphous silicon and has taken aim at utility scale and grid-tied commercial installations. XsunX has developed proprietary techniques that have enabled it to achieve outstanding efficiency levels for amorphous silicon.

The company plans a production capacity of 25 MW in 2009 and is aiming for 100 MW in a few years. It has also recently contracted to supply 15 MW of its solar modules, worth over $37 million, over 2 years. XsunX and United Solar Ovonics are the only listed companies that are real investment plays on silicon based thin-film technology. Yes, Canon, Sharp and even Mitsubishi are in the game, but those companies are diversified into so many other products that investing in them wouldn’t be a play on solar.

Other companies manufacturing amorphous silicon thin film include Auria Solar in Taiwan, EPV in New Jersey, Free Energy Europe in France, Heliodomi in Greece, Polar PV in China, Shenzhen Topray in China, Sinonar in Taiwan, TerraSolar in New York and VHF-Technologies in Switzerland.

2. The next approach to thin film manufacturing uses cadmium telluride (CdTe) as the semi-conductor material. While CdTe modules are cheaper and faster to produce, so far they are much less efficient at around 10%. For utility scale installations, that seems not to be a critical factor however. The leader in this field is First Solar (FSLR) with over 1 gigawatt of production capacity, over 600 megawatts shipped so far, and over 3.8 gigawatts of contracted sales, worth $6.3 billion through 2013. According to their annual report, First Solar’s gross margins are 56%, which is twice that of most of their competitors’ costs. And they claim their cost per Watt to be $1.29, half to a third of their competitors. First Solar’s objective, though, is to be at $0.65-0.70 per Watt by 2012. After a tremendous run through 2007 up to May of 2008, when the stock went from about 28 to over 300, it tumbled to 85 for a brief while in November of 2008 only to rebound recently to around 130. One of the other CdTe developments was an Ohio company, Solar Fields, which was bought last year by Q-Cells, a German company. Ava Solar, in Colorado, has recently secured $104 million in funding and plans to large scale manufacturing in 2009.

3. Another group of companies is manufacturing cells with Copper Indium Gallium Di-Selenide (CIGS) as the semi-conductor. These include ICP Solar in Quebec, Solyndra in California, Global Solar in Arizona, MiaSole in California, Heliovolt in Texas, TerraSolar in New York and Nanosolar in California. All of these companies remain private. One of the biggest efforts currently is coming from Honda, who is a major player in crystalline silicon cells. CIGS systems have demonstrated efficiencies that approach 20%, which is significantly higher that CdTe modules and close to the efficiency of crystalline silicon modules. However, to date at least, the manufacturing processes are less tolerant to change.

Third-generation PV technologies includes approaches such as dye-sensitized solar cells, quantum dots, nano-antennaes, nanomodified materials and organic cells. These all offer the promise of higher efficiencies and lower costs than even second generation technology. But none is yet clearly established as a leader, and none of these technologies is yet available as an exchange traded investment.

Related posts:

1. Moser Baer, SunEnergy to Build 1 MW Thin Film Solar Plant @ Chandrapur
2. Zebasolar Gets approval for 36 MW thin-film PV plant in India
3. HHV Solar Makes New Thin Film Solar Cell Tech
4. 150 MW Thin-film Manufacturing Planned by KSK Surya
5. Ascent Solar, Kirloskar enter Strategic Alliance for India’s CIGS thin-film market