Evaluating Decarbonisation Pathways in Road Transportation via Life Cycle Assessment

Abstract

This study aimed to quantify the carbon footprint of different private cars and urban buses technologies. For private cars, the highest carbon intensities were associated to internal combustion engines propelled by gasoline. Moreover, when fueled by bioethanol both technologies displayed a competitive carbon footprint, associated to the low footprint of the vehicle. Fuel cell-based technologies were less competitive when compared to other technologies as their environmental performance was heavily influenced by the vehicle burden. Thus, if technical and financial hassles were resolved, the solid-oxide fuel-cell vehicle would represent a promising technology in order to tackle greenhouse gas emissions while providing an option for synergy between electrification and biofuels. Regarding urban busses, biodiesel was found to be an option for carbon mitigation; however, the environmental and health hazards of other emissions remain a concern, which makes the case for the solid-oxide fuel-cell bus and the electric bus. Moreover, the large uncertainties related to land use change of soybean biodiesel could seriously hamper the potential carbon mitigation of biodiesel. All-in-all, the strategies for climate change mitigation in the transport sector should be designed taking into account the local conditions and all the available options at a given time.