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Wednesday, July 20, 2011
Thin Film Solar: The Market That Isn't : Greentech Media
What are the common issues faced by thin film manufacturers?
And what will it take for the thin film industry to grow?
Thin film solar panels account for roughly 20 percent of the solar market and First Solar (Nasdaq: FSLR) makes up about half of the thin film market total. First Solar has a two-gigawatt capacity this year and an announced capacity of three gigawatts for next year.
Here are the 2010 thin film rankings:
But what really makes a market? Is it a common set of materials and processes and tools?
If that's the definition -- then there really isn't a PV thin film market according to a (very interesting) presentation by Dr. David Eaglesham, the CTO of First Solar.
Eaglesham made the point that even within the CdTe (cadmium telluride) materials systems, there's no standard process. First Solar uses a Vapor Transport Deposition (VTD) process, while Abound Solar and PrimeStar/GE use a Close Space Sublimation (CSS) process for their CdTe manufacturing. Solexant employs semiconducting nanoparticles in an ink.
And within the CIGS materials system, you'd be hard-pressed to find a pair of vendors using the exact same processing technologies. In the words of Frank Yang, Senior Director, Business Development at Stion -- "Saying CIGS is like saying cake." There are lots of different cake recipes.
Co-evaporation is used by Johanna, Solibro, and Wurth. Nanosolar uses a printing technique. SoloPower uses a process akin to electroplating while Avancis, Stion, and Solar Frontier use a sputtering technique. And each of those players has their own unique spin. Some firms work with cells like AQT, while others create a monolithic module like ISET or Stion.
Helfried Weinzerl, Manager Business Development, Solar PV, at CH2M Hill observed that CIGS could stand for Challenging Industrial and Global Standardization.
In a technology still in rapid growth mode, vendors, especially leading vendors, are going to stubbornly reject efforts to standardize. It's just not in their best interest to standardize -- at least not yet.
Ben Bierman, Executive VP, Operations & Engineering at Solyndra noted that the unique nature of their cylindrical solar product meant that they had to create their own in-situ test equipment. Until an outside vendor arrives with a better solution, Solyndra has no reason to join in a standardization effort, according to Bierman.
Bettina Weiss of SEMI noted that standards will eventually reach thin-film PV just as they have reached crystalline silicon.
Thin film solar technology boasts a superior carbon footprint compared to energy-intensive crystalline silicon solar modules. Eaglesham said that thin film can claim the shortest EPBT (energy payback time) by a large measure -- First Solar's EPBT is 0.8 years (EPBT includes manufacturing and installation).
It's not enough to base a common market on, but it's a shared thin film attribute --
and it's a start.
frpm the comments
more info on thin film technology;
Hi Eric, you did better research in your articles about CIGS before (or was it Micheal Kannelos?) Johanna was never using a coevaporation process, its a sequential process - depositing metal precursors by sputtering followed by a more or less rapid processing step in Selenium and/or Sulfur atmosphere - like Solar Frontier, Avancis, Stion, Centrotherm and Sulfurcell, because all have the same origin ARCO! By the way, Johanna was bought by Bosch and is now called Bosch CISTech, Sulfurcell was renamed to Soltecture and started CIGSe-module manufacturing using a coevaporation process. The other companies using coevaporation are Global Solar, Ascent, Solarion, Solyndra, Würth and Solibro. These companies are using processes simliar to the 3-stage co-evaporation process developed by NREL, which leads to world record efficiencies (20.3% by ZSW). Coming to some exotic processes and companies: Nanosolar - sequential process, but instead of sputtering the precursors are prepared by applying an ink (similar to ISET); Solopower - sequential process, but instead of sputtering the precursors are prepared by electrodeposition (similar to CIS Solartechnik, Odersun or NEXCIS); Miasole - reactive sputtering, simliar to coevaporation but insterad of thermal evaporation the metals are sputtered (companies using a simliar approach: AQT, XsunX).