Environmental Impacts of Perovskite Solar Cell Materials: Transparency and Reproducibility Gaps, and Reporting Recommendations.

As renewable energy deployment grows and silicon solar cells approach their efficiency limits, perovskite solar cells (PSCs) emerge as a promising next-generation photovoltaic technology. PSCs environmental impacts are assessed via life cycle assessment (LCA), which depends on the availability of high-quality life cycle inventories (LCIs). In this study, we systematically identified 101 LCIs related to PSC materials, aiming to recommend the most reliable among them. However, we found that all inventories rely on secondary data and frequently omit critical details such as production scale. We also reproduced reported inventories and found large discrepancies in environmental impacts-sometimes differing by several orders of magnitude across sources. These inconsistencies, coupled with poor documentation, prevented the identification of a single best inventory for any material. Instead, we recommend the use of the most detailed inventories characterized by the highest number of inventory flows as a basis to build more transparent inventories. Our findings demonstrate how gaps in transparency, documentation, and reproducibility in PSC materials inventories impede decision-making and erode confidence in LCA results. To address these issues, eleven steps are proposed when developing LCIs for emerging materials.