Designing, sizing and economic feasibility of a green hydrogen supply chain for maritime transportation

Green hydrogen plays a strategic role in the decarbonization of the maritime transportation. A step useful to favor the use and the exploitation of the hydrogen is the development of hydrogen supply chains that, by including both the infrastructures and the end users, can simplify the economic issues and the authorization processes. This paper is focused on the designing, sizing and economic feasibility of a sustainable supply chain that consists of a solar-driven electrolysis system that generates hydrogen for powering a fuel cell-based propulsion system installed on board a small passenger ferry boat travelling on a short route. The sizing procedure is based on a numerical procedure that aims to find the optimal supply chain configuration, in terms of components’ sizes, able to satisfy the hydrogen demand and to sustain the electrical energy requirements by only using the renewable source. Results of this study highlight that a hydrogen production of 128.7 tons/year is produced by using an alkaline electrolysis unit of 1780 kW integrated with a 8.15 MWp photovoltaic power plant. The produced hydrogen allows to satisfy the specific requirements of the ferry boat with a total number of 314 roundtrips per year. From the economic point of view, by valorizing the electricity surplus and the by-product oxygen from the electrolysis process, the estimated profitability index and the discounted payback period are 2.03 and 9 years, respectively, making the investment attractive. The calculated levelized cost of the produced green hydrogen is equal to 5.61 €/kg. These results demonstrate the techno-economic feasibility of the proposed supply chain based on hydrogen technologies that, being already available on the market, can be effectively implemented to support the decarbonization of the maritime sector.