Carsharing exemplifies a growing trend towards service provision displacing ownership of capital goods. We developed a model to quantify the impact of carsharing on greenhouse gas (GHG) emissions. The study took into account different types of households and their trip characteristics. The analysis considers five factors by which carsharing can impact GHG emissions: transportation mode change, fleet vintage, vehicle optimization, more efficient drive trains within each vehicle type, and trip aggregation.

Global emissions scenarios studies, such as those informing the Intergovernmental Panel on Climate Change (IPCC) 5th Assessment Report (AR5), highlight the importance of the transport sector for climate change mitigation—along with the difficulties of achieving deep reductions therein (1) [supplementary materials (SM)]. Transport is responsible for about 23% of total energy-related CO2 emissions worldwide (2). The sector is growing more rapidly than most others, with emissions projected to double by 2050.