Strategies for the decarbonization of a port industrial area: design and operation optimization of a hydrogen hub

The exploitation of hydrogen as energy carrier is addressed as one of the most promising alternatives to decarbonize the industrial and mobility sectors. Green hydrogen produced via electrolysis from renewable sources could be directly used in the so called “hard-to-abate” sectors or provided as fuel for terrestrial and maritime vehicles. This study aims to design and optimize a green hydrogen hub in a port industrial area in the North-East of Italy. Hydrogen is produced using a polymer electrolyte membrane electrolyzer powered by a grid-integrated PhotoVoltaic (PV) plant. In particular, hydrogen production is meant to provide hydrogen to a Hydrogen Refuelling Station (HRS) for a fleet of 20 vehicles and to satisfy the demand of the hydrogen batch annealing in a steel production plant. A compression station, a two-level compressed gas storage system, and the HRS components (dispenser and chiller) are also included in the model of hydrogen production and storage plant. A multi-objective approach has been adopted to optimize the design and operation of the proposed hydrogen hub, finding the levelized cost of hydrogen optimal in environmental and techno-economic terms. The analysis shows that for the hydrogen demand of both the annealing process and 20-car fleet, a 341 kWP PV plant coupled with an 89 kW electrolyzer is required, resulting in a hydrogen cost of 7.80 €/kgH2. The port area decarbonization through the development of such hydrogen hub could lead to a potential CO2,eq emission avoidance of about 153 tons/year, where 120 tons/year are avoided only by decarbonizing the annealing process. The approach used in the analysis could be further exploited for other industrial areas or other hydrogen uses.