Performance Evaluation of Hydrogen-Powered Internal Combustion Engine City Bus for the Urban Mobility of Bologna, Italy

Abstract

Abstract Due to its geographical features, northern Italy is particularly prone to poor urban air quality and air pollution. Vehicular emissions are one of the main sources of pollutants and greenhouse gases emissions. Reducing the number of vehicles and promoting collective urban sustainable mobility represent the best solution to cut-down emissions from the transport sector in urban contexts. Among the possible solutions, hydrogen-fuelled internal combustion engines are particularly attractive, due to the interesting compromise between low manufacturing cost and low emissions (CO2 is absent, while other pollutants can be easily kept under control). Despite the lack of a distribution network, the operational path of hydrogen urban buses is known a priori, allowing them to operate without relying extensively on distribution infrastructure. This study presents a performance evaluation of a hydrogen-powered internal combustion engine bus within the metropolitan area of Bologna, Italy, assessed on two distinct routes representing diverse typical operating conditions. Through a dedicated virtual vehicle model, the performance of the bus is assessed in terms of fuel efficiency and NOx emissions. Additionally, a sensitivity analysis is conducted to evaluate the impact of variations in both the bus weight and passenger load on its performance metrics. The findings of the present study provide valuable insights into the sustainability of hydrogen buses for urban contexts, paving the way for their adoption as a sustainable transport solution.