Performance characterisation of photovoltaic modules

A review of the performance characterization of photovoltaic modules is given, that charts the progress made in the European research project ‘PV-Performance’ as well as other work carried out in Europe. The aim is to illustrate the measurement and prediction accuracy of energy delivery. It is shown that direct inter-comparisons of PV modules may have as much as 6.5% uncertainty in the comparability between modules and that any difference much lower than this is not a meaningful conclusion. A significant contribution to this is the determination of the rated power of the modules chosen for the inter-comparison and the lack of statistical numbers. The rated power is also important in the context of modeling the performance and thus must be as accurately as somewhat possible. It is shown that the uncertainties of the calibration laboratories are not borne out by round robin inter-comparisons and further work is needed in this field. Uncertainties for wafer-based devices are shown to be in a range of ±3%, while different thin film technologies may have higher uncertainties. It is shown that even simple modeling approaches are good enough to predict PV performance to within the measurement accuracy of most datasets.