A comparative analysis of the potential of carbon emission reductions from shared micro-mobility

Shared micro-mobility systems (SMSs) have recently experienced rapid growth, providing new green mobility options to reduce energy use. To better understand SMS's environmental impact, this paper comparatively examines the potential of carbon emission reductions from dockless shared bikes and e-bikes in three Chinese cities at different economic development stages (i.e., Binjiang, Wucheng and Xiangshan) using massive user-generated trips. Results show that shared bikes and e-bikes in the three cities reduced 41.51 and 31.84 tonnes of CO2 emissions over a week, respectively. The trip-level environmental benefit of shared e-bikes is 155.11 g of CO2, higher than that of shared bikes (132.03 g). Most of the reduced carbon emissions are from substituting driving trips, but shared e-bikes even generate extra carbon emissions by substituting public transit and walking. Patterns of carbon emission reductions show spatiotemporal heterogeneity. Spatially, reduced carbon emissions are concentrated in central areas of Wucheng/Xiangshan and more dispersedly distributed in Binjiang, which is a more economically vibrant city. From a temporal perspective, SMS's carbon reduction patterns are similar to typical temporal usage patterns. The Dining and Shopping trips contribute the most to SMS's carbon reductions in all cities. Binjiang has more carbon emissions reduced from the Transfer and Working trips, and shared bike trips with the Home and Schooling purposes reduced relatively more carbon emissions in Wucheng. Our analysis helps us better understand the environmental impact of SMSs across various urban contexts and inform relevant transport planning to achieve carbon neutrality in cities.