Technical and economic comparison of different electric bus concepts based on actual demonstrations in European cities

Abstract

Battery-powered electric buses are increasingly being used around the globe. This work investigates four technological concepts for the rollout of electric buses from a technical and economic perspective: very fast and moderate opportunity charging, overnight charging and trolley hybrid buses (power supply via catenary/battery). The investigations fund on real demonstrations in four European cities. They were carried out in direct cooperation with the respective public transport operators to obtain realistic results. The focus of this work is on an economic comparison based on the total cost of ownership (TCO), including all investment and operating costs in the bus service. Thereby, the battery represents a major asset and is examined more closely, especially with regard to the expected service life. The TCO of corresponding electric and diesel buses, scaled up to a complete line, are directly compared. This includes penalty costs for the emissions of noise and pollutants. Sensitivity analyses on the most relevant variables are conducted to take into account risks and uncertainties. It shows that electric buses can nowadays already be economically competitive under favourable assumptions, regardless of the concept. Trolley hybrid buses turned out to be the most cost-effective variant in their respective country.