LONDON Xunlight Corp. (Toledo, Ohio), a developer of lightweight, flexible thin-film silicon solar modules, has announced it has demonstrated wide-web, roll-to-roll photovoltaic manufacturing process for the production of thin-film silicon photovoltaic modules.
The roll-to-roll manufacturing process allows the company to produce triple-junction thin-film silicon solar cells on rolls of thin stainless steel substrates, three feet wide and up to one mile long.
The stainless steel web is guided through a series of vacuum chambers for the deposition of nine semiconductor layers using a plasma enhanced chemical vapor deposition process and back-reflector and top electrode layers using a sputtering process. The combined thickness of the layers for the triple-junction solar cell is approximately one hundredth of the thickness of a typical sheet of paper. It therefore uses only a small amount of silicon.
The design, development, engineering and construction of Xunlight's production equipment were made with its Series A and Series B private equity investments from four institutional investors: Emerald Technology Ventures, Trident Capital, NGP Energy Technology Partners, and Rabo Ventures, and with major grant awards from the State of Ohio's Third Frontier Project, the U.S. Department of Energy and the U.S. Department of Commerce.
Using its three-foot wide roll-to-roll manufacturing line, Xunlight has produced flexible PV modules measuring between 3-ft by 5-ft and 3-ft by 18-ft.
The 3-ft by 5-ft modules demonstrated 8.77 percent initial aperture-area efficiency, which, after extended light exposure, is expected to stabilize at 7.4 percent aperture-area module efficiency.
"This is a significant milestone for us," said Xunming Deng, president and CEO of Xunlight, in a statement. "Everyone at Xunlight, particularly those in the design, engineering, construction and production teams, have worked extremely hard to make this possible. We are very proud of our talented and hardworking team."
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