"The Photovoltaic (PV) industry needs to find new approaches to make solar cells competitive. Crystalline silicon (c-Si) wafer-based technology has a real potential to achieve significant cost reduction if the R&D effort is made on the most critical issues. These issues are the reduction of silicon material consumption, the increase of solar cell efficiency and an improved integration into modules. In this context, silicon heterojunction solar cells, the active part of which is basically produced by a low temperature growth of ultra-thin layers of silicon onto both sides of a thin crystalline silicon wafer-base, represent clearly one of the most promising options. The HETSI project aims to design, develop and test novel aSi-cSi Heterojunction solar cell structure concepts with high efficiency. This project covers all aspects of the value chain, from upstream research of layer growth and deposition, to module process and cell interconnection, down to upscaling and cost assessment of heterojunction concept. The Consortium is a balanced team of 12 partners from 6 European countries with a wide range of expertise in the field of silicon for PV covering various aspects from the deposition of thin silicon films, passivation of interfaces, through characterization and modelling, down to technological implementation and industrial achievement capabilities. The cooperation of Europe’s leading research institutes in the field of heterojunction solar cells (HMI, ECN, CEA-INES, IMEC, UNINE, UU, ENEA and CNRS) will generate synergy effects that will help to provide the know-how needed to reach the optimum relation of cell efficiency and cost. The presence in the consortium of 3 industrial partners, Q-Cells, Photowatt and Solon, which are among the leading European solar cell and module producers, will insure a rapid and efficient economic exploitation of HETSI results."