SulfurCell

SulfurCell was a German company established in 2001 in Berlin, operating in the renewable energy sector with a focus on thin-film solar module manufacturing. The firm was a spin-off from the Hahn-Meitner Institute, now the Helmholtz Centre Berlin for Materials and Energy, which is noted as Europe's largest research center for thin-film photovoltaics. This origin provided the company with deep technical expertise, which it successfully transferred from research to industrial-scale production.

The company specialized in developing and producing solar cells based on copper indium sulfide (CIS) and later copper indium gallium selenide (CIGS/CIGSe) technology. Its business model centered on manufacturing these modules and supplying them for building-integrated photovoltaics (BIPV), as well as residential and commercial rooftop applications. The target clients included architects, property owners, and a network of system integrators and installers. Revenue was generated through the sale of these solar modules, which began in Europe in 2005 and later expanded to the U.S. in 2010.

SulfurCell's modules were distinguished by their use of a thin CIS layer, which absorbed as much sunlight as silicon layers a hundred times thicker, resulting in lower material and energy consumption during manufacturing. Key features included a sleek, black appearance popular with architects, high efficiency in hot temperatures, and a lower voltage that reduced system costs. The modules were IEC-certified, demonstrating durability by maintaining performance for over 2,000 hours at 85 degrees Celsius and 85 percent humidity. A significant milestone was achieved in 2008 when the company was ranked sixth on the inaugural Guardian/Library House "CleanTech 100" list. The firm attracted considerable venture capital, with investors like Intel Capital, Vattenfall Europe, and Gaz de France Suez contributing to funding rounds, including a notable €85 million raised in July 2008 and another €18.8 million in January 2011. In 2009, SulfurCell rebranded to Soltecture to better reflect its evolution towards integrated solar, technology, and architecture solutions. However, faced with intense market competition and rapidly falling prices for conventional solar modules, the company filed for insolvency in May 2012.

Keywords: thin-film solar, copper indium sulfide, CIS, photovoltaics, building-integrated photovoltaics, renewable energy, solar module manufacturer, Soltecture, cleantech, solar construction