TY - JOUR A1 - Heberl, Michael A1 - Hofrichter, Andreas A1 - Rank, Daniel A1 - Bauer, Franz A1 - Sterner, Michael T1 - Influence of plant dimensioning and location on the ecology of PEM electrolysis JF - International Journal of Hydrogen Energy N2 - PV and wind systems with PEM electrolysis offer great potential for producing hydrogen with low emissions. Our research has identified the ecologically optimal size of PEM in relation to fixed PV/wind capacities. We calculate efficiencies and production volumes for PEM with 240 capacity and site variations. We analyse the global warming potential of all systems and draw conclusions about the optimal system design. The lowest GWP is achieved at the site with the highest full load hours with 1.32 kg CO2-eq/kg H2 (Wind, 28 MW electrolysis) and 4.24 kg CO2-eq/kg H2 (PV, 23 MW electrolysis). We have identified a clear trend: increasing PV/wind full load hours leads to higher ideal PEM capacities. However, there is a significant discrepancy between the ideal economic and ecological capacity. Furthermore, higher electrolysis capacities can achieve lower emissions as they increasingly operate at a more efficient partial load. KW - Electrolysis KW - Life cycle analysis KW - Global warming potential KW - Plant design KW - Renewable energy Y1 - 2025 U6 - https://doi.org/10.1016/j.ijhydene.2025.151039 SN - 0360-3199 VL - 167 PB - Elsevier ER -