This study explores the effects and severity of microcracks within Solarge’s innovative lightweight polymer-based photovoltaic modules, aiming to recommend a grading criterion specific to the company’s product range. Unlike the traditional PV modules which predominantly employ a glass and aluminum frame, Solarge utilizes lightweight, fully recyclable polymers. The uniqueness of Solarge’s composition presents a novel landscape in terms of durability and degradation trajectories. A pivotal concern arises from the introduction of microcracks, which inherently diminish a PV module’s power output. Leveraging Solarge’s extensive database of current-voltage measurements and electroluminescence images, an initial analysis discerned the emergence of small diagonal and v-type cracks post-production, predominantly after the lamination process. Subsequent experimental methodologies, encompassing mechanical loading and temperature cycling on these modules, demonstrated the growth of these existing cracks into diverse and more complex formations. This evolution of stressors significantly compromised module performance. A categorization system classifying cracks into noncritical (Category 1), critical (Category 2), and very critical (Category 3) was developed, with associated power losses identified for each. Using linear regression, predictive models for crack progression in each category were established. The study culminated in the formulation of a grading criterion proposed to Solarge, aiming to refine their quality assurance.