The transition to a decarbonised energy system requires a cost-effective, reliable and sustainable supply of renewable hydrogen, particularly for industrial hubs like the Port of Rotterdam. Multiple supply pathways could potentially contribute to such an energy system, with each pathway characterised by different advantages and disadvantages. Therefore, it is crucial to consider the system-wide implications of various supply pathways in order to make balanced trade-offs. This study functions as an exploratory investigation into the relations between various system designs and their characteristics. It examines techno-economic trade-offs between local hydrogen production using offshore wind-powered electrolysis and cracking of imported ammonia. Key performance indicators for system affordability, security of supply and sustainability are defined in order to facilitate a comparison of the two supply pathways. Employing a quantitative system model, these indicators are evaluated across different system configurations and demand scenarios for the Port of Rotterdam.
This research highlights the complexity of the energy transition and the absence of a universally optimal hydrogen supply pathway. Local electrolysis offers lower operational costs and import independence but requires high capital investment. In contrast, ammonia imports ensure a stable supply with lower local capital expenditure but depend on a resilient supply chain and are highly sensitive to ammonia costs. Local production demands more space but has a lower carbon footprint, while imports require less space at the import site but result in higher emissions. Additionally, electrolysis competes with power demand in Rotterdam’s harbour-industrial complex and hinterland, adding strain to their decarbonisation efforts. Local production also requires multiple salt caverns for storage due to constrained extraction rates, along with significant overcapacity in wind power and electrolysis to ensure supply continuity. Conversely, import-dependent systems rely on large ammonia shipments, and as hydrogen demand increases, local production reaches clear supply limits, leading to greater import reliance.
Future research should expand model applicability to different locations and supply chains, enhance key performance indicator scope, and incorporate stakeholder-driven decision-making frameworks. Ultimately, an effective hydrogen strategy must balance affordability, security of supply and sustainability, navigating the trade-offs between supply pathways and their broader implications for the energy transition.