Environmental and climate impacts of a large-scale deployment of green hydrogen in Europe

Green hydrogen is expected to play a vital role in decarbonizing the energy system in Europe. However, large-scale deployment of green hydrogen has associated potential trade-offs in terms of climate and other environmental impacts. This study aims to shed light on a comprehensive sustainability assessment of this large-scale green hydrogen deployment based on the EMPIRE energy system modeling, compared with other decarbonization paths. Process-based Life Cycle Assessment (LCA) is applied and connected with the output of the energy system model, revealing 45% extra climate impact caused by the dedicated 50% extra renewable infrastructure to deliver green hydrogen for the demand in the sectors of industry and transport in Europe towards 2050. Whereas, the analysis shows that green hydrogen eventually wins on the climate impact within four designed scenarios (with green hydrogen, with blue hydrogen, without green hydrogen, and baseline), mainly compensated by its clean usage and renewable electricity supply. On the other hand, green hydrogen has a lower performance in other environmental impacts including human toxicity, ecotoxicity, mineral use, land use, and water depletion. Furthermore, a monetary valuation of Life Cycle Impact (LCI) is estimated to aggregate 13 categories of environmental impacts between different technologies. Results indicate that the total monetized LCI cost of green hydrogen production is relatively lower than that of blue hydrogen. In overview, a large-scale green hydrogen deployment potentially shifts the environmental pressure from climate and fossil resource use to human health, mineral resource use, and ecosystem damage due to its higher material consumption of the infrastructure.