Organic photovoltaic modules integrated inside and outside a polytunnel roof

Abstract This paper investigates the differences electrical behavior and lifetime of organic photovoltaic (OPV) modules installed inside, on the outside of a polytunnel type greenhouse roof andon a fixed frame next to the polytunnel with the aim of finding an installation location that would reduce degradation and therefore prolong the lifetime OPV modules in a greenhouse application. The modules had different degradation rates, influenced by three factors: exposure to harsh weather conditions, mechanical stresses on the modules caused by the movement of the greenhouse plastic sheeting they were fixed to, and dust accumulation on the modules. Efficiency values of modules declined to 32%, 47% and 47% and fill factor values reduced by 33%, 21% and 21% for modules on top of the polytunnel, inside the polytunnel and on frames adjacent to the polytunnel respectively during the measurement period. Installing OPV modules inside a tunnel can increase module lifetimes and consequently increase the overall lifecycle output of the modules. Not fixing the OPV module directly to the polyethylene cover, thereby avoiding the stresses on the module due the film movement, could improve OPV lifetimes further.