A sustainability assessment for public buses : A multi-criteria approach

Abstract: Many city planners, regional authorities and transport providers are tasked with the challenging job of selecting which type of public buses are suited to their location and priorities. The challenges of which are multidimensional in nature due to different policies to adhere to as well as economic, environmental and technical tradeoffs between options. The aim of this report was to provide decision support in the choice of powertrains and energy sources for buses in public transport systems. The methodology used was a multi-criteria analysis. The assessed transportation options include buses running on diesel, biogas, fatty acid methyl esters (FAME), hydro-treated vegetable oils (HVO), bioethanol as well as battery electric vehicles (BEVs) assessed separately as opportunity and overnight charging. Suitable bus solutions were broken into six key areas to be considered when selecting fleets. These involved economic, technical, reliability, infrastructure, environmental and social issues. The economic considerations highlighted: the cost of ownership and the market share of vehicles. Vehicle performance considerations included: the range/refuel time of a vehicle. Considerations involved in delivery reliability were: national energy security, whether there was a short-term backup fuel as well as current and future policy support. Another consideration regarding infrastructure was: the required level of change required. Regarding environment and energy, considerations of merit involved: well-to-wheel greenhouse gas reductions, air pollution in relation vehicle regulations, noise levels, nutrient recyclability as well as associated resource impacts. The social considerations were determined as: public opinion and job creation. From the compiled results assessing each criterion the grading matrix suggested it was biogas buses followed closely by HVO buses that scored the best. Weighted results were also conducted, emphasizing the most important criteria according to surveyed stakeholders which resulted in HVO and Biogas again performing the best.