Cost-Effective Approaches to Recycle Current and Future Waste Solar Modules
Authors: Bhattacharjee Jyoti , Roy Subhasis 
Published: December 2024

Recycling solar panels has been a revolutionary procedure that has affected sustainability practices in the renewable energy industry in the past, present, and future. With silicon photovoltaics contending for market share to reduce solar power costs, perovskite photovoltaics is becoming more popular. However, there is currently no practical means to manage dangerous lead Pb waste, which could spell the end of this technology. We offer a material management method for perovskite solar modules that addresses the end of their useful life. The goal is to recycle valuable transparent conductors and toxic lead to save the environment and promote the economy using recycled materials. An action plan for removing poisonous lead and precious glass substrates from perovskites-based solar panels. Organic solvents, such as dimethylformamide (DMF), dissolve lead in the perovskite layer during delamination of encapsulated perovskite solar panels. To entirely remove lead from organic solvents, an adsorbent adsorbs ions, eluted into a clean solvent for broth enrichment, and the precipitated PbI2 is collected for recycling. In this case, we used carboxylic acid cation exchange resin as an absorber to recycle lead from used perovskite modules. To reuse the used perovskite solar cells, a procedure must first be developed to unbind the encased modules and expose them to the perovskite layer. This section examined the composition of a perovskite module formed of indium tin oxide (ITO) glass and encapsulated by an additional piece of glass. Although silicon solar panels contain a large number of valuable materials, such as silicon, glass, silver, aluminum, etc., they still lack the cost-effective recycling technology that would allow them to be recovered. Silicon is incredibly diverse, but its high-value applications, such as semiconductors, require the same stringent purity requirements. However, employing it as an anode material in lithium batteries with less severe purity standards appears viable.

Furthermore, abandoned solar cells have been shown to include silicon anode impurities such as boron, phosphorus, and silver, which improve their stability. There are now two phases in PV recycling: dismantling and filtration. Although silicon PV panels vary greatly, they all share the same basic construction. The sandwich construction solar cells, comprised of aluminium, silicon, and silver, are joined to modules by copper wires soldered with lead and tin (Pb and Sn). The modules are then sandwiched between two EVA layers, creating a waterproof seal.

Alternative processes, like pyrolysis and chemical treatments, are used to gently peel off glass and solar cells to recycle Si and Ag by removing or extracting EVA. EVA is commonly used to coat and preserve solar cells and PV panels. This encapsulation makes it more difficult to separate the glass cover and back sheet and recycle the solar cells.

Morphology conversion must be considered throughout the upcycling process, which employs nano-metal catalysed hydrofluoric acid (HF) acid etching to recover porous Si/carbon anode materials after a brief purification step. Because of the properties of silicon, HF is always used to form silicon pores, which are not meant to last. As a result, HF can be replaced in purification and morphological modification, resulting in a more environmentally friendly and long-lasting recycling process. The silicon wafer can also be recycled in all-solid-state batteries (ASSBs). This method states that after removing the perovskite and carbon, the metal oxide layers (TiO2, ZrO2) produced on the FTO can be reused to remanufacture enclosed carbon-based perovskite cells. In a solar simulator based on xenon lamps, the power conversion efficiency of perovskite solar cells and solar modules was measured using current-voltage (JV) measurement. Based on the study and comparison of solar PV production and the avoided burden approach due to recycling, it is possible to infer that recycling in the total life cycle evaluation of solar PV can result in a significantly higher impact reduction throughout the solar PV recycling process.

Keywords

Solar module recycling, Chemical recycling, End-of-life management, Upcycling, Circular economy, Refurbishment.