Solution and vapour deposited lead perovskite solar cells: Ecotoxicity from a life cycle assessment perspective
Abstract
We present a life cycle analysis (LCA) and an environmental impact analysis (EIA) of lead based perovskite solar cells prepared according to the two most successfully reported literature methods that comprise either vapour phase deposition or solution phase deposition. We have developed the inventory for all the components employed for the two different device architectures that resemble respectively a traditional dye sensitised solar cell (DSSC) and an inverted polymer solar cell (OPV). We analyse the impacts from generation of 1 kWh of electricity and assume a lifetime of 1 year in the analysis and further present a sensitivity analysis with the operational lifetime as a basis. We find that the major impact comes from the preparation of the perovskite absorber layer due to the electrical energy required in the manufacture and also make the striking observation that the impact of toxic lead(II)halides is very limited compared to methylammoniumhalides employed. This applies during the raw materials extraction, synthesis of the starting materials and manufacture of the perovskite solar cells and from these points of view the lead based perovskite solar cells do not pose extra concerns when compared to contending solar cell technologies in the cradle-to-gate scenario considered here. The environmental impact of the perovskite solar cells in the operational phase and the decommissioning phase representing a cradle-to-grave analysis is not currently possible and will have to await large scale outdoor demonstration where emission to the environment during the operation and decommissioning phase can be measured. The main conclusion is that in the cradle-to-gate analysis there are no compelling reasons to dismiss lead based perovskites as a solar cell technology.