Adaptive infrastructure planning through fluid-dynamic simulations: A case study of Germany’s hydrogen core network

The development of large-scale hydrogen transmission networks requires infrastructure decisions under substantial uncertainty regarding future demand, supply locations, project maturity, and implementation timing. This study develops and applies a simulation-based adaptive infrastructure assessment framework for hydrogen transmission networks. Methodologically, it extends an established three-sphere gas network modeling approach by introducing an Adaptive Infrastructure Assessment Sphere, which operationalizes network agility by linking candidate eligibility assessment and investment-based prioritization with fluid-dynamic baseline characterization, cumulative topology modification, fluid-dynamic re-simulation, technical assessment, and economic interpretation. The framework is applied to Germany’s legally approved Hydrogen Core Network. Based on the most recent publicly available scenario data of the Hydrogen Core Network from July 2024, sectoral hydrogen demand and supply are spatially allocated to the reconstructed network topology. All six official network usage cases documented in the Hydrogen Core Network application and approval process are simulated under hydrogen-specific steady-state conditions, including real-gas thermodynamics, compressor modeling, pressure and velocity constraints, convergence behavior, and demand fulfillment criteria. The approved topology fulfills the transport tasks of this complete set of official network usage cases, with two localized screening-threshold exceedances in the Winter Load case. The eligibility assessment identifies 37 candidate subprojects. Following investment-based prioritization and cumulative re-simulation under the same prescribed NUC transport tasks, a modified topology excluding the sections associated with KLN042–01 and KLN098–01 continues to fulfill all transport tasks of the six official network usage cases under the assessed steady-state conditions. The modification reduces the planned network length by approximately 418 km and corresponds to an estimated investment reduction of €1.386 billion, equivalent to approximately 7.4% of total network investment. An illustrative sensitivity analysis additionally evaluates the associated compressor electricity demand and potential operating-cost implications. The results demonstrate how simulation-based adaptive infrastructure assessment can provide an additional technical evidence layer for adaptive, phased, and demand-aligned hydrogen infrastructure planning under uncertainty.