Experimental performance assessment of curved PV modules for vehicle-integrated photovoltaic systems

Flexible photovoltaic modules are vital for vehicle-integrated photovoltaics due to their lightweight and adaptability to aerodynamic curved surfaces. However, quantifying their performance losses under mechanical bending remains a critical challenge. This study experimentally quantifies how mechanical bending affects the electrical performance of flexible photovoltaic modules for such applications. An experimental setup provided single-axis curvature control from 0° to 20°, together with two pyranometers measuring global horizontal irradiance and plane-of-array irradiance, and a data logger for sampling power, irradiance, and ambient temperature. Collected data were filtered and analyzed through regression techniques to quantify the relationship between bending angle and photovoltaic power output. Regression modeling approaches showed strong explanatory power with R2 greater than 0.91, identifying the bending angle as the dominant driver of power loss. Notably, the results revealed that as the bending angle increased from 0° to 20°, the daily average power output decreased significantly, ranging from 11.6% to 47.6%. Additionally, the practical implications of these results were analyzed using curve correction factor calculations. The calculated curve correction factor differs notably from theoretical predictions reported in literature, revealing substantially higher power losses in real-world conditions. These outcomes provide critical insights for optimizing flexible module integration in vehicle-integrated photovoltaic applications.