Process design and global sensitivity analysis of hydrogen fuel station with dual-operating modes for a sustainable H2 city: Iterative optimization-based simulation using generalized disjunctive programming

•IOS framework for deriving optimal design and operational strategies.•The demand fluctuations and size were investigated in four regional cases.•The H2 station design and operational strategies for each region were derived.•Global sensitivity analysis provides optimal distributed H2 fuel station. This study proposes a novel process involving dual-mode operation for an on-site hydrogen (H2) refueling station. In particular, two distinct H2 production technologies, steam methane reforming (SMR), and autothermal reforming (ATR), are simultaneously considered, which enables a flexible operational mode that responds to operational variability. By synergistically combining the technical advantages of these two technologies (i.e., the low cost of SMR and the short start-up and shut-down times of ATR), the proposed fuel station can reduce a H2 storage tank cost, which is needed to respond to demand fluctuations. To achieve our goal, we developed iterative optimization-based simulation (IOS) framework. The proposed framework determines the optimal design configuration (e.g., the storage facilities and the capacity of production) and the dual-mode operational strategy (e.g., on/off timing) under demand fluctuations and given CO2 emission targets. The case study showed that lower storage costs and offset the increased capital cost of the production facility, thereby leading to a low H2 supply cost of 3.60 USD/kg and a production capacity of 1.2 tons/day. We then performed a global sensitivity analysis to provide a comprehensive strategy and practices for the deployment of the proposed system over demand levels, regional demand fluctuation, and CO2 emission targets.