EPFL PV-lab developed lightweight colored PV modules in Neuchâtel

Researchers at the École Polytechnique Fédérale de Lausanne (EPFL), PV-lab in Neuchâtel, Switzerland, have developed lightweight colored photovoltaic modules under 6kg/m². The design uses transparent polymeric foil as both the front pane and encapsulant, which helps maintain optical coupling with incoming solar radiation. Structural rigidity is provided by a composite backsheet with a polypropylene-based honeycomb core sandwiched between fiber-reinforced skins. Two skin variants were tested with fiber densities of 820 and 660g/m². A colored interlayer foil has been added for aesthetic appeal. The modules were subjected to flexural bending, static load, UV, damp-heat, thermal cycling, and humidity-freeze tests. Additional tests included hail impact and fire ignition. Fiber density in backsheet skins has affected mechanical performance. The system is intended for retrofitting buildings not designed for heavy loads.