Scenario-based recycling strategies for perovskite-silicon tandem solar cells: a harmonized life cycle assessment study

Abstract

Tandem solar cells allow for the increase of the overall power conversion efficiency (PCE) beyond the single-junction limit. However, despite their high PCE, tandem cells can be responsible for relevant environmental impacts during their life cycle. This paper presents a harmonized scenario-based life cycle assessment of five perovskite-silicon tandem solar cells from the cradle to the grave. Based on the global warming potential (GWP) indicator, we quantified and compared the environmental performance of different recycling strategies that can be implemented for monolithic and mechanically stacked tandem cells. The recycling strategies address a wide range of possible solutions to address the lifetime gap between silicon and perovskite semi-cells of tandem devices, giving support to the development and evaluation of an optimum recycling strategy that could be a solution to the end-of-life management of tandem cells. Moreover, a sensitivity analysis was performed on the tandem cells' operational parameters. The results highlight the environmental impacts of the recycling strategies, with the most sustainable waste management option identified as the one with the least environmental impact. The sensitivity analysis allowed us to find the environmental breakeven point for the lifetime, stability of the perovskite layer and efficiency of tandem cells.