How do ecoinvent system models, recycled materials, and powertrain influence the ecodesign of an automotive component?

Road transport is crucial in modern society, but it is one of the most greenhouse gas intensive sectors due to its heavy reliance on fossil fuels. Lightweighting, electrification, and recycling offer promising pathways to reduce environmental impacts. The goal of this article is twofold: First, perform a life cycle assessment (LCA) to evaluate the impacts of a carrier frame used to provide mechanical support to the instrument cluster made of a lightweight polyphenylene sulfide (PPS) composite, comparing two ecoinvent attributional system models for the background data. Alternative materials to the PPS are compared: PPS composite with 30 % recycled PPS and aluminum with 70 % and 95 % aluminum scrap recycled. The influence of weight-induced energy consumption during the use phase is analyzed for both internal combustion engine vehicles (ICEVs) and battery electric vehicles (BEVs). Second, conduct a scenario analysis to evaluate the most influential parameters driving environmental trade-offs, integrated with stochastic multi-attribute analysis (SMAA) to support decision-making under uncertainty. The results show that the PPS composite with 30 % recycled PPS presents the lowest impacts in most categories, while aluminum alternatives are sensitive to the choice of the ecoinvent system model due to the allocation rules for treating waste by-products and recyclable materials. The weight-induced energy savings from lightweighting do not provide a significant impact reduction for BEVs, as they do in ICEVs, showing that cradle-to-gate impacts become relatively more critical as the impact of the use phase decreases. This article highlights the benefits of recycled materials as ecodesign strategies for automotive components. • LCA of an automotive component combining methodological and technological scenarios. • Weight-induced energy analysis savings from lightweighting in ICEVs and BEVs. • PPS composite with 30 % recycled content achieves the lowest environmental impact. • Lightweighting yields limited impact reduction for BEVs compared to ICEVs. • Ecoinvent system models significantly influence results for high-recycled aluminum.