Results of the round robin calibration of reference solar cells within the PhotoClass project

An intercomparison of terrestrial photovoltaic (PV) calibrations was performed among a number of European calibration and testing laboratories that participated in the European Metrology Research Program (EMRP) project “PhotoClass”. The purpose of this intercomparison was to evaluate the comparability of calibration and testing services within the stated uncertainties of the individual laboratories. The calibration objects were two World Photovoltaic Scale (WPVS)-type reference solar cells, one made from crystalline silicon and one made from GaAs. The calibration value was the short circuit current under standard test conditions (ISTC). In conclusion, it was found that the calibration values are all consistent within the stated uncertainties. This result strengthens the reliance in the calibration chain and in the PV calibration infrastructure in Europe.