Energetica India 89 - May 2020

crunch of these critical minerals threatens the future of these clean energy technologies. In this context, the end-of-life management and recycling of these products are crucial. It will ensure sustainability by ad- hering to the concept of circular economy, support new in- dustries, and create employment opportunities. The metals can be reused within the industry to locally manufacture more products in future that can bring down the cost of these tech- nologies. Further, as mining of these metals creates as much waste as land filling, material recycling will decrease the envi - ronmental impact at the manufacturing stage as well. Current recycling procedures PV modules A majority of the PV module mass comprises of aluminium frames and glass, followed by the metallic components in so- lar cells and wires.The main steps of recycling PV modules include dismantling, combustion, and etching. Dismantling involves removal of metal frames and terminal boxes from the modules. Combustion involves burning the modules to remove the or- ganic encapsulant. This process ensures recovery of glass and solar cells (silicon or thin-film) with minimal breakage. Etching involves treating the residual mixture of glass and met- als with acid or alkali for the separation of these two compo- nents. After recovering glass, the composition of acid or alkali solution is changed to recover the different metals. Lithium-ion batteries Depending of the application, lithium-ion batteries come in varying size and chemistries. The basic structure has a cath- ode, an anode, and an electrolyte. These components are packed in an aluminium or plastic case. Broadly, the battery recycling process involves dismantling, crushing, and pro- cessing. Dismantling refers to the removal of the externalities such as aluminium or plastic case encasing the cell. Crushing refers to the process of grounding the cell to powder. This is followed by sieving to remove the tailings and other waste from fine metal particles. Processing is a broad term for recovering the metal compo- nents. This is a multi-step process involving treatment with al- kali or acid, extraction and stripping. The metal ions recovered by treatment with acid and alkali are dissolved in organic sol- vents. As each metal has a different level of solubility in these solvents, we get a mixture of metal solutions. Then, the solution is brought in contact with solid metal or alloy, which reduces the ions present in the liquid phase. The resultant solution is heated at ambient temperature and pressure to remove the organic solvent and get metals. Owing to multiple steps, these methods are energy intensive and less efficient. So, the focus of the recycling processes should be to decrease the number of steps. Also, because of the presence of different metals, there is a strong possibility of metal contamination in the recovered mass. Therefore, module and battery recycling requires separate recycling processesto efficiently recover and reuse the materials. Way forward for India India is yet to have a dedicated PVwaste management and recycling policy. At present, solar module and battery waste is treated as general electronic waste and comes under the Ministry of Environment, Forest and Climate Change.However, given the distinct nature of this waste and the economic value of the components, it is necessary to have a separate regu- lation in place. At present, India’s PV module manufacturing industry is underdeveloped and majority of the modules are imported from countries like China. Having a module recy- cling policy in place can make India self-reliant by ensuring a sustainable supply of raw materials and creatingemployment opportunities. Unlike India, several countries are already working to address the impending waste disposal problem. Some noteworthy mentions are the European Union’s Waste Electrical and Elec- tronic Equipment (WEEE) Directive, the United States module manufacturer First Solar, and pilot projects by Japan’s New Energy and Industrial Technology Development Organisation (NEDO).India can learn a lot from these countries to frame a regulation for its rapidly developing clean energy market. Firstly, working on the lines of EU’s WEEE directive, India can revise its existing electronic waste management framework to include PV modules and batteries. The revised regulation, 37 energetica INDIA- May_2020 SOLAR POWER