Techno-economic analysis of green hydrogen ferries with a floating photovoltaic based marine fueling station

Abstract The current study assesses the development of zero-carbon marine fuel production, storage and fueling for short-distance ferries from both technical and economic aspects. The solar driven integrated system is therefore designed in a stand-alone and carbon-free manner. The integrated system mainly consists of three parts: electricity production, hydrogen production and fueling, and hydrogen-driven propulsion systems. The land shortage of the urban environment is achieved by using a floating photovoltaic system, which is integrated with a proton-exchange membrane electrolyzer and a hydrogen tank to produce and store the hydrogen. A proton-exchange membrane fuel cell is used with auxiliary buffer batteries to power the propulsion system of ferries. A case study is carried out for the Toronto Island ferries urban transit system in Ontario, Canada. The current fossil fuel-driven ferry propulsion system is replaced with the proposed propulsion system with hydrogen fueling and production station. The developed system is thermodynamically and economically investigated where both energy and exergy approaches are used to carry out the thermodynamic analysis, and the cost comparison methods are deployed with various criteria, including internal rate of return, pay-back period and net present value. Also, additional maritime fuel comparison analysis is carried out for 2021 and 2030 cases at various hydrogen production capacities. A transient analysis is carried out to investigate the integrated system more deeply for each hour in a year to observe the vulnerabilities, provide more insightful details and maintain the decision-making process for component capacities. According to the case study, the proposed system's overall energy and exergy efficiencies in the grid-connected mode are calculated as 15.35% and 16.19%, respectively. The net present value of the proposed system is found to be 5.06 million Canadian dollars. The investment is paid back in 7.25 years with an 11.75% internal rate of return. The cost of hydrogen production, storage and fueling for the proposed system is found to be 6.47 Canadian dollars per kilogram at a 26.7 ton/year production rate.