Methodology for the Evaluation of Static Loads on Bifacial Modules Using a Test Bench
Abstract
The increasing incidence of low-energy glass fracture in modern photovoltaic modules, particularly in large-area bifacial designs, poses a significant threat to long-term reliability. This trend is associated with recent design changes, including increased module dimensions and the adoption of thinner, heat-strengthened glass. To investigate the underlying structural behavior, this study presents an integrated approach combining experimental static load testing, using strategically placed strain gauges, with Finite Element Method (FEM) simulations. The results conclusively demonstrate that under a uniform load, the highest mechanical strains do not occur at the geometric center but are instead concentrated along the module's lateral longerons. This behavior is governed by the aluminum frame, which redistributes the load and transforms the glass-frame interface at the edges into the most structurally critical zones. This mechanism elucidates the field-observed fracture patterns that initiate at the module's edges and highlights the limitations of current certification protocols.
Keywords
glass, strain gauges, stress, photovoltaic modules, solar