Gabion with Photovoltaic Module Ballast: Ground Structure Constructed from the Reuse of the Aluminum Frame

A bibliographical and experimental exploration of the recycling streams for monocrystalline silicon photovoltaic modules unveils ongoing limitations. Mechanical grinding processes block the efficient differentiation of conductive and insulating materials; chemical processes engender the formation of solid and liquid effluents having an adverse environmental effect; and thermal processes are limited by the production of noxious gases and by their high-energy demand, thus limiting scale-up. Hybrid processes are typically used only for recovering a given material stream. Conventional recyclers accept items like cables, connections, and junction boxes; but frames, usually separated mechanically, become contaminated by glass and sealant, losing value. Because many components of newly manufactured (after 2020) modules cannot be accepted by collecting and recycling facilities, traditional recycling processes (mechanical, thermal, and chemical) have been practically tested and proved impractical in this study: grinding hinders material separation; thermal processes emit hazardous gases and consume large amounts of energy; and chemical processes produce toxic waste without efficient delamination. To overcome these issues, we conceptualized and experimentally tested an immobile ground structure built at the landfill site only from discarded modules: the frame forms the mechanical structure and glass/laminate provides ballast, supporting and fastening new modules. Such a structure is strong, simple, and long-lasting, needing no concrete, and reduces the use of transport and landfill space. Such a reuse route overcomes the practical and economic issues we spotted in available recycling processes.