From Bifaciality to Yield: Different Bifacial Cell Technologies May Differ Even More in Annual Outdoor Performance

A comparative outdoor test of different bifacial P-PERC and N-PERT PV modules was designed and operated in Freiburg, Germany. According to LG Electronic's specifications, the chosen mounting geometry and albedo deliver a high bifacial gain. While this is not comparable to typical commercial PV systems, it emphasizes differences in the bifaciality and the bifacial gain of the module samples. A greater bifacial gain was expected already for the N-PERT modules. However, the measurements revealed more differences in annual and in high resolution performance data. Laboratory measurements do confirm the observed outdoor behavior, given they are performed under bifacial conditions as well.