Towards suitable practices for the integration of social life cycle assessment into the ecodesign framework of hydrogen-related products

The hydrogen sector is envisaged as one of the key enablers of the energy transition that the European Union is facing to accomplish its decarbonization targets. However, regarding the technologies that enable the deployment of a hydrogen economy, a growing concern exists about potential burden-shifting across sustainabilitydimensions. In this sense, social life cycle assessment arises as a promising methodology to evaluate the social implications of hydrogen technologies along their supply chains. In the context of the European projects eGHOST and SH2E, this study seeks to advance on key methodological aspects of social life cycle assessment when itcomes to guiding the ecodesign of two relevant hydrogen-related products: a 5 kW solid oxide electrolysis cell stack for hydrogen production, and a 48 kW proton-exchange membrane fuel cell stack for mobility applications.Based on the social life cycle assessment results for both case studies under alternative approaches, the definition of a product-specific supply chain, making use of appropriate cut-off criteria, was found to be the preferable choice when addressing system boundaries definition. Moreover, performing calculations according to the activity variable approach was found to provide valuable results in terms of social hotspots identification to support subsequent decision-making processes on ecodesign, while the direct calculation approach is foreseen as a complement to ease the interpretation of social scores. It is concluded that advancements in the formalization ofsuch suitable practices could foster the integration of social metrics into the sustainable-by-design framework of hydrogen-related products.