Bifacial PV modules

A bifacial PV module is a solar panel designed to use light reaching both its front and rear sides. The front-side rating is still read like an ordinary PV module rating, while rear-side contribution is an additional condition-dependent gain from reflected or diffuse light reaching the back of the module. Manufacturer datasheets may show bifaciality, bifacial gain or rear-side test cases, but those figures depend on the module, mounting height, tilt, row spacing, rear shading, soiling and the reflectivity of the surface beneath or behind the module. A bifacial module label is not a promise of a particular annual generation figure, a flat-roof design, a fire-rating verdict, MCS certification, DNO approval or proof that a roof or mounting system is suitable.