Estimating rebalancing activities and vehicle use for existing station-based bike share systems

Rebalancing is an important process in bike share system (BSS) operation. Due to the lack of data on the rebalancing operation, existing studies have to rely on strong assumptions for system sustainability evaluation and efficiency improvement. To address this gap, this study proposed a framework to estimate rebalancing activities and rebalancing vehicle-miles-traveled using public data. Applying the framework to BSSs in Chicago, Boston, and Los Angeles, this study estimated the real-world rebalancing operation and analyzed the efficiency. Our analysis shows that: (1) only a small proportion of stations were involved in daily rebalancing; (2) most rebalancings were conducted during daytime, with limited overnight rebalancing, showing that the common assumption of overnight rebalancing in related studies needs reconsideration; (3) we observed a correlation between system scale and rebalancing efficiency. Results can provide critically needed benchmarks of the real-world rebalancing operation to support studies in bike share sustainability evaluation and rebalancing optimization.