Effects of Low Noise Emissions of Electrical Vehicles for Pedestrian Accident Risks

Following the political discussion of global warming and the political objective to support green mobility, in particular electric mobility, there is a substantial discussion whether or not electrical vehicles are dangerous for pedestrians based on their low noise level. This paper aims at answering the question regarding the specific injury risk resulting from electrical vehicles. The study is based on two pillars. On the one hand there is the analysis of published accident data regarding the impact velocity dependent injury risk of pedestrians. On the other hand noise emissions of the same car with electrical propulsion system, gasoline propulsion system and diesel propulsion system in constant speed and acceleration are acquired. Car noise emissions are caused by the propulsion system but also by the tyres and aerodynamic effects. The study shows that significant differences in noise emissions only exist in high acceleration phases and low speed conditions. Based on the accident data analysis both situations do not appear to be important with respect to severe injuries (low speed) and accident risk (high acceleration). In total it is estimated that the number of killed or seriously injured pedestrians will not change with the largely introduction of electrical vehicles. Accidents that are felt not to be dangerous may occur more often with silent propulsions systems.