A Comparison of Carbon Dioxide Emissions between Battery Electric Buses and Conventional Diesel Buses

To prove the important role of battery electric buses (BEBs) in reducing carbon dioxide (CO2) emissions, we propose a framework to compare CO2 emissions between BEBs and conventional diesel buses (CDBs) based on low sampling frequency BEBs data at the city scale in Shenzhen. We applied the VT-Micro model to improve the estimation of CDBs' CO2 emissions. A modal-activity-based method was implemented to reconstruct the second-by-second trajectories from the dataset as the input of the VT-Micro model. We updated the data of the Guangdong power generation mix to improve the estimation of BEBs' CO2 emissions. The experiments showed that BEBs could reduce CO2 emissions by 18.0-23.9% in comparison with CDBs when the frequency of air-conditioning usage was low. In addition, BEBs tended to achieve more CO2 emission reduction benefits when the transit buses traveled at a low speed. Improving the traffic efficiency of road networks and promoting inter-provincial electricity trading are important to promote the adoption of BEBs.