Coating photovoltaic (PV) cells with liquid silicone could yield more robust, sustainable solar cells at a fraction of the cost of traditional ones. Solar panels deliver power without risk to the environment and climate, but their durability comes at a financial cost. For solar panels to exceed life spans of 25 years, scientists must investigate various types of protective coatings to shield the solar cells from harmful environmental influences. To help protect the fragile silicon solar cells within a panel, manufacturers have used expensive ethylene-vinyl acetate (EVA) coatings. Now, researchers at the Fraunhofer Center for Sustainable Energy Systems (CSE) and Dow Corning Corp. are investigating a cheaper alternative material to protect solar cells: silicone. Silicone is a promising material and has been used to encapsulate PV modules, but until now, it has not been widely used for laminating solar modules. In this mechanical test stand, the researcher examines the quality of silicone-encased solar modules. (Image: ©Fraunhofer CSE) Prototypes of silicone-laminated cells were prepared by Fraunhofer scientists and tested in a climate chamber at low temperatures under cyclic loads. The cells were then tested with a light flasher and electroluminescence imaging to detect microcracks. In comparison with traditional solar modules, the silicone-encased PV modules were more resistant to cyclic loading of the type panels experience in strong winds, in particular at extremely low temperatures of −40 °C. “The study results demonstrate that silicone lamination is well-suited for certain applications, because the silicone protects the fragile components on the inside well and, moreover, withstands severe temperature fluctuations,” said project manager Rafal Mickiewicz. The findings, which were published at the 26th European Photovoltaic Solar Energy Conference, could help improve understanding of material requirements for solar modules, particularly in regard to sustainability and output, said Andy Goodwin, global science and technology manager of Dow Corning Solar Solutions. For more information, visit: www.fraunhofer.de/en
Photosensitizers