Integrated electrochemical modelling, spatial site selection, and multi-objective optimization of renewable-powered alkaline water electrolysis for green hydrogen production

Green hydrogen produced through renewable-powered alkaline water electrolysis represents a promising pathway toward decarbonization; however, large-scale deployment requires integrated optimization of site selection, electrolyzer operation, and energy system design. This study presents an integrated framework combining GIS-based multi-criteria decision analysis, an electrochemical alkaline electrolyzer model benchmarked against literature experimental data, and multi-objective optimization to evaluate off-grid, desalination-supported green hydrogen production systems. Eight coastal sites were identified based on solar irradiance, wind resources, ambient temperature, terrain characteristics, and proximity to export infrastructure. Hourly simulations of photovoltaic, wind, battery energy storage, and alkaline electrolysis systems were performed to simultaneously minimize the levelized cost of hydrogen (LCOH) and renewable energy curtailment while maximizing hydrogen production. The optimized systems achieved electrolyzer capacity factors of 45.1-77.1%, annual hydrogen production of up to 1165.3 tons/yr, and LCOH values of $ 6.19-16.35/kg. Hydrogen transportation and desalinated-water pipeline infrastructure contributed substantially to the lifecycle costs at several sites. Sensitivity analysis identified electrolyzer capital cost, transportation cost, and discount rate as the primary economic drivers of hydrogen production cost. The proposed framework provides a transferable approach for designing cost-effective renewable hydrogen systems in water-scarce coastal regions.