Hydrogen-powered public transport: A sustainable future for Favignana Island

Abstract

The road transportation of the Islands depends heavily on fossil fuels imported from neighboring regions, adding extra cost to fuel prices. Using these fuels for transportation contributes to high greenhouse gas emissions, creating another significant challenge. Replacing fossil fuels with alternatives that are not only environmentally friendly but also ensure local availability is the solution. Unlike most existing studies that rely on generalized assumptions or hypothetical deployment scales, this paper utilizes actual operational transport data from Favignana Island. It employs the HOMER Pro tool to conduct a realistic techno-economic analysis of on-site hydrogen generation using renewable energy sources for fuel cell buses. A hybrid microgrid system with solar PV, wind turbines, battery storage, electrolyzer, and hydrogen storage tanks has been designed. Hydrogen load is modeled considering real bus schedules for both peak and off-peak seasons. Among the four optimized systems proposed by HOMER Pro, the most feasible configuration, which comprises solar PV, wind turbines, battery storage, an electrolyzer, and hydrogen tanks, achieves a 90% reduction in greenhouse gas emissions and 30.8% cost savings over 20 years compared to the conventional diesel bus system. The optimal system yields a net present cost of € 325,214 and a levelized cost of hydrogen of € 5.19 per kilogram. The study further highlights the critical role of battery storage in enhancing cost-effectiveness by reducing reliance on intermittent renewable energy sources.