A novel state-of-charge-based method for plug-in hybrid vehicle electric distance analysis validated with actual driving data

Promoting Plug-In Hybrid Vehicles (PHEVs) is viewed as a promising strategy to mitigate the energy consumption and greenhouse gas (GHG) emissions in the transportation sector. The actual fuel and electricity energy consumption of PHEVs has recently attracted increasing attention. Distance-based average electricity or fuel consumption is commonly adopted to evaluate the energy efficiency of a vehicle. However, previous studies have predominantly focused on the ratio of electric drive distance to fuel drive distance and did not consider the difference between the electricity generated from onboard engine and offboard grid charging. This study proposes a grid electric driving ratio (grid-EDR) based on the battery energy variation under real road operation conditions for a more accurate calculation of the PHEV electric distance ratio. The method is validated by the actual vehicle driving data of 49 PHEVs in Shanghai and compared with other methods. To evaluate its application, the fuel substitution was calculated using grid-EDR combined with the new European driving cycle fuel consumption calculation method. PHEVs with higher grid-EDRs demonstrate better fuel economy. More than half the PHEVs in this study saved 50–80% of their onboard fuel. By improving the charging frequency, such as constructing more charging infrastructure, grid-EDR can be increased to 0.88 to reduce fuel consumption and greenhouse gas emissions from the transportation sector.