Targeting carbon emissions mitigation in the transport sector – A case study in Urumqi, China

Promoting changes in the transport energy mix is critical to reducing carbon dioxide emissions from the transport sector. The development of zero-carbon energy or low-carbon energy has thus become an accelerating global trend. This work develops a systematic integrated framework to support carbon reduction for an urban transport system. Firstly, a transport metabolism model is proposed. Secondly, based on the Intergovernmental Panel on Climate Change (IPCC) carbon accounting approach, carbon emissions of passenger transport systems are calculated. According to carbon emissions reduction policies and the transport metabolism, four hypothetical scenarios are investigated. Under the constraints of carbon emissions targets and transport demands, the carbon emission pinch analysis (CEPA) method is used to determine the minimum demand for zero-carbon energy and optimize the energy mix of transport modes. Passenger transport in Urumqi, China is analyzed as an illustrative case study. For the optimal scenario, the zero-carbon energy (electricity) demand is 1.07×109 kWh. The optimal energy mix for private cars is that electricity, gasoline, and compressed natural gas usage accounting for 14.5%, 25.5%, and 60%, respectively. The unit emission reduction cost of policies is evaluated for the specific policies. The implementation priority of the policies is then determined. The potential transport mode shift is determined by a marginal cost diagram. The transport–energy nexus is also considered. Results show that the most effective measure of carbon emissions reduction in the transport sector is fuel switching. General policy implications of these results for other urban centers are then discussed. © 2020 Elsevier Lt