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Sulfurcell delivers its first CIS modules

Sulfurcell Solartechnik GmbH introduces its first thin-film modules. The company's answer to the current silicon shortage is the use of copper indium sulfide (CIS) – not to be confused with the similar sounding abbreviation for the common copper indium diselenide technology from Shell or Würth.

	© Biohaus PV Handels GmbH
Sulfur, not silicon: A test system using eight Sulfurcell modules at German wholesaler Biohaus.

The type of sulfur hiding behind the term »sulfide« in this abbreviation is the most unusual of these absorbers. Its high reactivity allows the copper and indium to bind in just a few minutes during the vapor deposition of the glass substrate at temperatures of 500 °C. According to Sulfurcell, the use of sulfur vapor cuts the number of production steps by one-third, and the energy demand by two-thirds. This is why the company's goal is to produce its modules at half the costs of ordinary modules by 2010, says Sulfurcell managing director Nikolaus Meyer. It's no wonder that the modules are awaited with much anticipation – particularly from investors, who have put around €16 million ($19.4 million) into the project.

The module's construction is fairly conventional, with an aluminum frame, front glass, and EVA as embedding material. What is unusual, however, is the high voltage level (by comparably low current) that the HV series (HV = High Voltage) generates with its 80 serially connected PV cells. The company also manufacturers a series with 2 × 39 serially connected cells, which in turn reduces the voltage by half but doubles the current (LV series). These devices are specifically designed for stand-alone systems. All modules are suited for a maximum system voltage of 1,000 V.

Several of the first modules produced by the company were delivered last September to German integrator and wholesaler Biohaus PV Handels GmbH for the construction of a small test system. In the second quarter of 2006, additional modules will be delivered to select German pilot customers such as IBC Solar and Krannich Solar, which along with Biohaus make up Sulfurcell's sales partners. One shouldn't expect to see a significant number of cells on the market until the second half of the year, says Sulfurcell's other managing director Ilka Verena Luck.

The nearly 0.8 m² large modules manufactured in serial production have powers of 52 W (model SCG52-LV) and 55 W (model SCG55-T). Their power tolerance is +/- 5 percent and the power guarantee is 80 percent of the minimum power over the course of 20 years. Sulfurcell's modules enjoy efficiencies of between 6 and 7 percent. Nowadays, modules using copper indium diselenide, like devices from Würth Solar, reach efficiencies of between 10 and 11 percent.

Sulfurcell, founded in 2001, intends to manufacture around 1.5 MW of modules this year, but plans to increase production volume significantly next year.

datasheet

Sulfurcell Solartechnik GmbH
Barbara-McClintock-Strasse 11
12489 Berlin, Germany
phone +49/30/6392380-0, fax -1
info@sulfurcell.de
www.sulfurcell.de