Photovoltaics (PV) should provide about 25% of the global electricity production by 2050, which will require large-scale manufacturing. PV is expected to be a clean technology that can reduce the carbon footprint of electricity production. To maximize carbon reduction and maximize the environmental benefit, we must reduce the environmental impact of the manufacturing stage. This work evaluates the life cycle environmental impact of manufacturing mature (silicon) and emerging (organic) PV and evaluates alternative processes.For organic PV, C60 is often used as an acceptor material in OPV. Existing C60 purification methods are energy-intensive and require a large quantity of hazardous solvents. Therefore, it is desirable to modify existing C60 purification methods before OPV large-scale production to mitigate the potential environmental, cost, and chemical hazards of the manufacturing process. We used life-cycle assessment (LCA) to identify the environmental hotspots of the purification process. In addition to LCA, green chemistry, toxicity assessment, and analytical chemistry were employed to identify greener replacements. The alternative C60 purification has lower environmental (59%), cost (85%), and chemical hazard (42%) impacts compared to the existing C60 purification process. For mature technologies such as silicon PV (Si PV), it is necessary to evaluate the amount of materials needed to meet the expected PV capacity additions. Si PV is 95% of the current PV market and is expected to remain the leading technology until 2040 (>50%). We estimated the amount of material necessary for Si PV manufacturing based on PV installation in the US and the rest of the world in the next ten years. A bottom-up approach was used to evaluate the required materials for each sub-Si PV technology (e.g., aluminum back surface field, PERC, heterojunction, mono facial, bifacial, and perovskite/silicon tandem). Solar glass with 74 million metric tons and metallurgical-grade silicon (MG-Si) with three million metric tons have the highest material demand in the next decade. MG-Si production requires silica sand extracted from high-quality quartz (>98% purity). This study identified the purity and availability of potential quartz deposits globally. The country-specific carbon footprint of silica sand production was evaluated for quartz with various purity. The carbon footprint of producing silica sand was about 36% higher for low-quality quartz (65% purity) than high-quality deposits. We also quantified the carbon footprint and the cumulative energy demand of silica sand production from legal and illegal mines. The lower cost of silica sand production from illegal mines could result in using illegal quartz in the Si PV supply chain. Therefore, it is essential to have third-party certifications to ensure that the PV supply chain is free from illegal quartz and PV consumers buy ethical products.
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