Shared mobility and vehicle lifetimes – implications for the carbon footprint

Abstract

Car sharing will likely increase the annual vehicle driving distance, which may accelerate passenger car retirement. We develop a semi-empirical lifetime-driving intensity model using statistics on Swedish vehicle retirement. We integrate our semi-empirical model with a carbon footprint model, which assesses future decarbonization of global, European Union, and Swedish energy systems. In this work, we show that the carbon footprint depends on both calendar age and cumulative driving distance of the vehicle. Higher driving intensities generally result in lower carbon footprints due to increased cumulative driving distance over the vehicle’s lifetime. Shared autonomous vehicles could decrease the carbon footprint by about 41% in 2050, if one shared vehicle replaces ten individually owned vehicles. However, empty travel by shared autonomous vehicles – the additional distance traveled to pick up passengers – may cause carbon footprints to increase. Hence, vehicles should be designed for durability to enhance the carbon footprint benefits of sharing.