Xunlight has successfully demonstrated its high-throughput, wide-web, roll-to-roll photovoltaic manufacturing process for the fabrication of high-efficiency thin-film-silicon solar modules. The R2R process enbales the production of triple-junction thin-film silicon solar cells on three-feet-wide, mile-long rolls of thin stainless-steel substrates at its 122,000-sq-ft facility in Toledo, OH.
The stainless-steel web runs through a series of vacuum chambers for the deposition of nine semiconductor layers using a plasma-enhanced CVD process as well as back-reflector and top-electrode layers using a sputtering process. The combined thickness of the layers for the triple-junction cell is a few microns.
Using its three-foot wide roll-to-roll manufacturing line, Xunlight has produced large-area (3 × 5 ft and 3 × 18 ft) flexible PV modules. The 3 × 5 ft modules, measured with a Spire solar simulator, demonstrated 8.77% initial aperture-area efficiency, which, after extended light exposure, is expected to stabilize at 7.4% aperture-area module efficiency, the company said.
Xunlight says that its R2R manufacturing technology allows for much lower capital cost compared with the current state of the art, enabling the company to rapidly ramp up its production capacity in the near future.
"This is a significant milestone for us," said Xunming Deng, Xunlight's president/CEO. "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."
Xunlight designed, developed, engineered, and built its own manufacturing equipment with the assistance of its academic partner, the University of Toledo's Thin Film Silicon Photovoltaic Laboratory.
The design, development, engineering, and construction of the company's production equipment were funded with about $40 million in Series A and B private equity investments from four institutional investors--Emerald Technology Ventures, Trident Capital, NGP Energy Technology Partners, and Rabo Ventures--and with multimillion-dollar grant awards from the state of Ohio's Third Frontier Project, and the U.S. departments of Energy and Commerce.