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After a week away from the blog, I noticed a few items apart from the German feed-in tariff controversy that merited discussion. The first Solar Short Takes edition of the new year recognizes an emerging solar materials powerhouse region, ponders a Hong Kong company that seems to be in it for the long haul, and examines a recent CIS/CIGS conversion efficiency report.

Ain’t no place I’d rather be: A few years back, the idea of Tennessee becoming one of the hotbeds of solar materials manufacturing would have likely resulted in more than a few raised eyebrows. Not that the Volunteer State hasn’t played a small part in the photovoltaics industry, since Sharp has been assembling crystalline-silicon modules in Memphis for awhile.

But over the past year, Hemlock and Wacker have announced plans to invest a couple billion dollars in polysilicon production facilities in different parts of the state, and last week single-crystal silicon start-up Confluence Solar said it will spend a couple hundred million to build a plant in Clinton. The Feds also awarded advanced energy manufacturing tax credits to Sharp (to add another module line) and Wacker (to go toward building that billion-dollar poly plant). 

Although none of the factories has been completed and won’t be for a couple of years, by the mid-2010s, tens of thousands of polysilicon will be produced in the state that has historically played a key role in the public utility/energy biz as the home of the massive Tennessee Valley Authority….

Eye on GCL: Speaking of poly, Chinese solar materials producer GCL-Poly Energy has been a very prominent current in the newsflow this month. The company’s project development unit celebrated the activation of a 20MW PV power system in Xuzhou (one of the largest in China), its M&A arm augmented the firm’s portfolio with the acquisition of a controlling interest in wafer-maker Konka Solar, and the equipment purchasing folks announced they had spent more than $40 million on tools and services from GT Solar and another nearly $34 million on wire saws from Meyer Berger.

GCL’s aggressive capacity expansion plans for 2010—bringing another 21,000MT of poly online and reaching 2GW of wafer capability—combined with its move downstream into PV power generation (a sector it has a presence in with conventional and wind energy assets on the mainland) make the Hong Kong-based company one to watch in the coming year….

Efficiency consistency: In the competition to lay claim to the highest CIS/CIGS conversion efficiency on record, Avancis said NREL has verified that the company has reached aperture-area efficiencies of 15.1% on a fully encapsulated 30 x 30cm glass module. The company also claims that standard production efficiencies have reached 11% on its newly commissioned 20MW line in Torgau. Although the German firm’s pride in its accomplishments is duly noted, let’s take a closer look at those numbers. 

The NREL tests confirmed aperture-area efficiencies, not total-area efficiency, a number which is likely to be lower by at least a percentage point--and for some experts is a more compelling figure. The 30x30cm² CIS minimodule tested by the national lab is not a commercial-size device--the company’s PowerMax units are almost ten times larger, at 159.5 x 68.4cm. No one will be installing 900cm² panels on their rooftop or ground-mounted array.

Champion efficiencies may spur bragging rights, but the real proof comes in the production pudding. Avancis’ manufacturing-line efficiency numbers are vague and do not indicate whether they are representative of the median efficiencies coming off the line or only those found on the higher end of the distribution curve. But assuming 11% is what the company regularly sees, that’s on par with the leading CIS/CIGS companies 

Remember that the roots of Avancis go back nearly three decades to the old Shell and Siemens CIS/CIGS R&D and production facilities in Camarillo, CA. That historic line was producing fairly large-area 40W CIS modules in the early ‘90s with median efficiencies exceeding 10% on a regular basis, and champion panels pushing past 12% in NREL and TUV testing under standard conditions. Is a few percentage points improvement all the progress one should expect 15 (or more) years later? 

Flash forward to the present, and a host of CIS/CIGS companies have seen hit module efficiencies in the 10%-12% range over the past year, with certain glass and flex champion cells and minimodules reaching the mid-teens in tests, both internally and at NREL, Fraunhofer ISE, and other labs.

A sampling of companies claiming double-digit efficiencies includes Solibro, Nanosolar, Jenn Feng, Showa Shell, Global Solar, Ascent Solar, MiaSole, Solarion, Solyndra, Johanna Solar, and centrotherm’s turnkey system customers. In fact, the number of firms that have yet to achieve at least 10% average conversion efficiencies on their pilot or production lines (such as Sulfurcell and Odersun) seems to be less than those who have.

While Avancis’ latest achievements may warrant a polite round of applause, what the news really says is that the company is one among many in the CIS/CIGS scrum who are doing what they need to do if they have any hope of competing against cheap silicon or First Solar CdTe modules in the market. I wouldn’t pop the cork on any celebratory vintage champagne just yet.