The research activities of the SOLAR 2013 project covered the main stages of the concentrator photovoltaics technology chain, focusing on aspects specific to multi-junction cells, photovoltaic modules and direct solar radiation.
Based on an updated analysis of the international market context and the state of development of Concentrator Photovoltaic (CPV) technology, research and development activities were carried out to grow triple-junction cells with a conversion efficiency of over 36%, to optimize the associated post-growth processes required to produce the complete device, and to develop and optimize techniques and tools for characterizing them.
Optimization and development activities also included innovative multilayer and prototype coatings (nanostructured) to improve the optical transmission (anti-reflective coating) of solar radiation incident on the cells, with the aim of increasing their efficiency, and on the modules (anti-reflective and anti-dirt coating). A new test facility was created to characterize CPV modules and, in particular, an innovative algorithm was developed to efficiently find the point of maximum power of CPV modules. The activities carried out in the project were completed by the collection and systematization of data on direct normal irradiance (DNI) in Italy, provided by various sites belonging to an ad hoc consortium, and by the development of a methodology for the accurate estimation of DNI at national level, in anticipation of the development of models that allow reliable prediction of the electrical producibility of CPV systems.