Comparison of electrical performance of bifacial silicon PV modules

The interest on the n-type crystalline silicon bifacial PV modules has increased in the last years since they can increase the performance in comparison to traditional PV modules. As the PV modules are generally sold according to the nominal power output and efficiency under standard test conditions STC, the lack of standards for bifacial modules leads each manufacturer to claim different amounts for the "added value" of the bifaciality that makes it difficult for customers to directly compare between bifacial manufacturers. In this work, we have compared the electrical performance of framed and frameless c-Si bifacial modules from 5 different manufacturers utilising rear covers of different reflectivity and different measurement methods such as a single-sweep flash simulator, the so-called multi-flash (MF) method, a largearea steady state sun simulator and under natural sunlight for the accurate measurement of the module parameters. It was observed that depending on the measuring method, some modules presented STC front power out of the tolerance range given by the