This report briefly describes the research activities carried out in 2016 as part of the three-year “Concentrator photovoltaics” project (2015-2017).

The project aims to help reduce the cost of concentrator photovoltaic (CPV) technology, making it more competitive with other energy sources and overcoming the technological barriers that still limit its full market penetration.

RSE’s research is aimed at developing and implementing innovative technological solutions at all stages of the technological supply chain, from the growth of multi-junction solar cells and the optimization of the associated post-growth processes required to produce the complete device, through to photovoltaic modules, in order to solve some of the major problems present in CPV systems developed to date.

These technological solutions, also in collaboration with research institutes and national and international operators, aim to increase the efficiency and reliability of CPV systems, thereby reducing their construction and maintenance costs.

During 2016, the development and optimization of the production process continued for the growth of the “top” sub-cell of a triple junction cell (with InGaP grown at low temperature or with growth of InGaAsP) which can also be integrated into a quadruple junction cell, continued. The first creations of SiGeSn layers reticularly adapted to GaAs were carried out using innovative deposition processes that required modifications to the MOCVD for growth in the same chamber of “contaminating” elements. The development of post-growth processes for small MJ cells (2.4×2.4 mm2) with high concentration (up to 1000x) and the development of anti-reflective coatings were also carried out. At the same time, the development and characterization of a prototype of a compact, high performance concentrating photovoltaic module continued, as well as the validation of the innovative MPPT algorithm for inverters connected to CPV systems and the low-cost solar tracking sensor integrated into the CPV module.

Finally, the Helios database of direct solar radiation and spectral irradiance was regularly updated at different national sites in collaboration with the members of a specific consortium, and a procedure for calibrating the measured spectral data was developed.