Photovoltaic performance of amorphous silicon flexible solar modules under mechanical loading

The applications of photovoltaic devices can be significantly expanded by directly integrating them into structures. Solar cells integrated into structures can help to power a variety of devices such as structural monitoring sensors and unmanned aerial vehicles (UAVs). However, little work has been reported in the literature on the performance of solar cells under deformation. Thus, a thorough investigation on the photovoltaic behavior of solar modules under mechanical loading is necessary in order to provide the optimal integration conditions for practical applications. The photovoltaic performance of commercially available amorphous silicon solar modules was tested under applied mechanical stresses. The current density-voltage characteristics were measured at increasing stress levels during a uniaxial tensile test. As strain increased, the short circuit current density decreased, and at strains greater than 1.4%, the fill factor, and maximum power point degraded. The performance degradation is attributed to micro-structural changes in the form of cracking under applied stress. These results are required to determine the allowable loading conditions and failure mechanism in solar module integrated structural systems.