Seven Years of Power Rating following IEC 62670-3

The IEC standard 62670-3 covering the power rating of CPV modules has been published in 2017. However, this rating procedure has already been applied for the first time at Fraunhofer ISE in Germany in the year 2014. Since then it has been used many times in Freiburg for several different CPV modules from various manufacturers. Amongst them are modules with different cell types (3J, 4J, 5J), various lens sizes (1x1 cm2 to 15x15 cm2), and lens types (PMMA, full glass, silicone on glass). In this paper some of the experiences which have been gathered in these 7 years since 2014 on the power rating of CPV modules are going to be presented. The measurement uncertainty of the IEC 62670-3 rating approach has been calculated exemplarily to 7 %rel. In this work we will present the main contributors to this measurement uncertainty and we will discuss the deviations which have been found for the VOC at 25 °C derived from dark vs light I-V curves. Furthermore, for several CPV modules of various technologies the nominal CSTC efficiency has been determined from indoor and outdoor light I-V measurements. The agreement between indoor and outdoor rating has been found with ±4 % in the worst case.