Social life cycle hotspot analysis of future hydrogen use in the EU
Authors: Martín-Gamboa Mario , Mancini Lucia , Eynard Umberto , Arrigoni Alessandro , Valente Antonio , Weidner Eveline , Mathieux Fabrice 
Published: July 2024

Abstract
Purpose
The widespread use of hydrogen in the EU aimed at reducing greenhouse gas emissions may involve complex value chains (e.g. importation from third countries) with potential effects (positive or negative) on the different sectors of society. Achieving sustainable hydrogen deployment must be motivated not only by environmental and economic aspects but also by social responsibility and the search for human well-being. Given this, and the scarcity of studies currently available on prospective social impacts of hydrogen production, the present purpose of this article is to unveil and assess the main social impacts linked to the future hydrogen value chains.

Methods
The methodological approach adopted in this article encompasses the following steps: (i) analysis of two potential value chains for hydrogen use in EU: an on-site option, where hydrogen is produced and used in the same European country, and an off-site option, where hydrogen is produced in a European country different from its usage involving more unit processes, in terms of storage and transport activities, and working time to deliver the same quantity of hydrogen. This framework will include (i) scenario analysis and a forward-looking perspective taking into account the critical raw materials employed across the entire value chain, (ii) identification of a list of relevant social impact categories and indicators through a systematic procedure, (iii) social hotspot analysis using Product Social Impact Life Cycle Assessment (PSILCA) to assess the selected representative value chains, and (iv) conducting scenario analysis and subsequently interpreting of results.

Results and discussion
The off-site value chain shows a relatively worse social performance (6 to 72 times) than the on-site value chain across most selected indicators due to the more complex value chain. Although the identification of social hotspots depends on the specific social indicator under evaluation, the power source components (wind and solar PV) manufacturing processes and the relatively increased complexity of the off-site option highly conditioned the social performance of the hydrogen value chains in most of the indicators considered. A scenario analysis was carried out comparing both value chains with two additional locations for hydrogen production: Northern Africa and Western Asia. The findings indicate that the on-site value chain presents the lowest impact scores. For the off-site option, the production of hydrogen in a European country is the most preferable scenario in terms of the social indicators evaluated.

Conclusions
According to findings, producing hydrogen in a different location than where it is consumed increases the social impacts of its deployment. Measures at mid and long term should be considered for improving the social impact of hydrogen deployment in Europe. This includes increasing reuse and recycling, responsibly sourcing raw materials, and creating regulatory frameworks ensuring safe working conditions across global value chains. Furthermore, this article highlights the crucial role of the S-LCA methodology in evaluating social aspects as a support for targeted policy interventions, and the need to adapt this to the specific case study. At the same time, it acknowledges that other relevant social aspects that can influence the social sustainability of the hydrogen technology are not captured with this methodology (in particular social acceptance, affordability and energy security). Improvements in selecting indicators and refined geographical and temporal representations of the value chains to better represent hydrogen technologies and future size market are research gaps filled in the present scientific work.