The recently launched Ecodesign for Sustainable Products Directive from the European Commission requires that spare parts for consumer products like washing machines be available for up to 10 years. This requirement poses challenges to current spare part strategies, as it increases the need for storage and demands more sustainable practices in spare part production and management. While additive manufacturing (AM), particularly stereolithography (SLA) printing, is recognised for its potential to minimise stockkeeping, waste, and transportation, most life cycle assessments (LCAs) have primarily focused on the printing process. Consequently, overall impacts related to logistics and storage, when compared to traditional injection moulding (IM), remain underexplored.

A critical knowledge gap remains in understanding how technological and material improvements, production scale, storage duration, and recycling practices influence the overall environmental performance of these strategies. In this study, a prospective LCA was conducted on a plastic washing machine spare part to evaluate these parameters. The assessment indicated that under current conditions, the SLA printed spare part has approximately twice the environmental impact of the IM and its 10-year stored alternative. However, future advancements in energy efficiency, resin formulations, printer lifetime extension, and other improvements could significantly reduce the environmental impacts of SLA and potentially make it competitive with IM. It was also found that while storage and transport requirements do increase the impacts of IM, the material impacts play a more crucial role. The assessment also revealed a crossover point for impacts at production volumes of around 250–350 parts, below which SLA becomes preferable.

These findings provide critical insights into sustainable long-term spare part provisioning and offer guidance for manufacturers and policymakers on enhancing the environmental sustainability of spare part provision. They also emphasise key development areas for researchers and AM technology developers to advance the sustainability of AM. Future research should focus on enhancing resin inventory data, examining recycling impacts, accurately assessing per-part energy consumption, and comparing more recent AM technologies with traditional manufacturing to determine the conditions under which performance crossovers occur.