Analysis of the performance of the Large Amorphous Silicon PV Façade in Ispra after 11 years of operation

We present the results of an analysis of the performance of a large facade-mounted amorphous silicon PV system at the Joint Research Centre, Ispra, Italy, after 11 years of operation. The results show that all 420 modules in the system are still operating. Detailed measurements of part of the system indicate that the nominal peak power remains at the design value of 21 kW (stabilized, after light soaking). The conversion efficiency of the a-Si modules have now stabilized at a value of around 3.2%, with some seasonal variation. Inverter efficiency is around 90%, the same as at the start of operations