Bifacial Module Testing

Bifacial modules, capable of additional power generation from the rear side, are a promising technology for increased energy yield compared to standard PV (monofacial) modules and with a low added cost. In order to provide customers and end-users confidence in the bifacial products now available on the market a clear laboratory test is needed that is both accurate and feasible with the current characterization equipment. A draft bifacial standard test has been proposed and suggests options for both full laboratory testing and characterization for modules from a manufacturing line. The authors conducted a survey of various parties in the PV value chain including institutes, module manufacturers, and equipment suppliers, gathering more information about the advantages and disadvantages of different test protocols and to use as a guide for recommendation for best practices after future laboratory evaluation.