Solar energy has long been advocated as being better for the environment than fossil fuels. However, amongst fears that solar cells production might release more hazardous gases than fossil fuels, Chinese authorities recently suspended production at a solar panel factory after protests by residents who blamed the plant for causing air and water pollution.
In India, the Ministry of Environment and Forests (MoEF), has exempted solar photovoltaic (PV) power projects from the ambit of environmental clearances.
Solar panel manufacturing generates a number of effluent gases contaminated with silane, trichlorosilane, dichlorosilane and hydrochloric acid (HCl), apart from chemicals like silicon, cadmium compounds, germane and polyvinyl fluoride-all of which are hazardous to the environment and people who are exposed to them. This manufacturing process also requires raw materials that have to be mined-quartz sand for silicon cells and metal ore for thin-film cells.
These materials are treated at different stages (in the case of silicon cells, these include purification, crystallisation and wafering). Finally, these upgraded materials are manufactured into solar cells and assembled into modules.