Techno-economic analysis of solar-powered green hydrogen production integrated with seawater desalination at coastal port facilities: A multi-configuration assessment for Italian ports

The global transition toward low-carbon energy has positioned green hydrogen as a key decarbonization carrier for coastal industries and maritime sectors facing simultaneous energy transition and freshwater scarcity pressures. However, comprehensive techno-economic studies that integrate seawater desalination, brine management, photovoltaic energy, and battery storage into unified green hydrogen production frameworks remain limited in the existing literature. This study develops a dynamic simulation model of a solar-powered Green Hydrogen Production System using TRNSYS and PVGIS platforms, assessing 36 configurations that combine three brine management designs, three photovoltaic capacities ranging from 5 to 10 MW, and four battery storage sizes at four Italian coastal port locations over a 20-year economic horizon. The Levelised Cost of Hydrogen ranges from 5 to 8 €/kg across all tested configurations, with the sea discharge design proving most cost-effective and Syracuse recording the minimum LCoH of 4.32 €/kg owing to abundant solar irradiance. Governmental subsidies between 7 and 12 M€ are required across all configurations to achieve the IEA competitiveness threshold of 1.5 €/kg. These outcomes establish geographic solar availability and brine management strategy as the primary economic determinants, confirming that coastal port infrastructure represents a strategically optimal platform for scalable green hydrogen deployment aligned with maritime decarbonization objectives.