Performance analysis and reliability of grid-connected PV systems in IEA countries

This paper presents operational performance results of grid-connected PV systems, as collected and elaborated for the photovoltaic power systems programme of the International Energy Agency (IEA). Performance ratios (PR) obtained from 334 PV installations in 14 different countries are compared and discussed. In Germany, there is a significant rise of PR between early installations in the nineties and new installations. For Switzerland, BIPV and other types show high PR>0.80, but average PR values lower than expected were obtained. For Japan, lessons learnt from the current monitoring programmes are used to improve PV system performance showing constant performance at high level. As an outcome of this work, reliable and worldwide monitoring performance data and results are available for future developments of financing schemes (e.g. feed-in-tariffs) in order to stimulate the PV market.