Comprehensive CO₂ emissions analysis and optimization of plug-in hybrid electric vehicles

Fuel and grid have different life-cycle carbon emission intensities, which makes plug-in hybrid electric vehicles (PHEVs) have great low-carbon potential. To reduce carbon emissions during PHEV driving, the energy allocation of PHEV based on carbon intensity is studied. The energy life cycle carbon emissions factors are collected and energy management strategies (EMS) are developed. A power-split PHEV model is established to analyze carbon dioxide (CO 2 ) emissions. Carbon emissions factors calculate the carbon emissions of each power flow. Simulation research is carried out using Tianjin and Yunnan’s energy structure as an example. The equivalent CO 2 emission minimum strategy (ECEMS) is established by optimizing the hybrid mode in the Rule-based strategy. Based on ECEMS, the improved particle swarm optimization (PSO) algorithm is used to optimize the rules of hybrid mode switching. As a comparison, the same method but a different goal is used to optimize energy consumption. The results show that the lowest energy consumption does not mean the lowest carbon emission. CO 2 emissions in different scenarios are reduced by 7.1%–31.7%, but the energy consumption is increased.