Study On Fuel Cycle Energy Consumption And Emissions Of Plug-in Hybrid Electric Vehicle

In recent years, Plug-in Hybrid Vehicle (PHEV) caused widespread concern in China,because of high fuel economy, low or zero-emission exhaust emissions, and the ability toreplace oil with coal, and the China’s "poor in oil, less in gas, rich in coal" energy structure.This paper reviewed the research and development progress of PHEV, and established aPHEV fuel cycle energy consumption and environmental emissions analysis model suitablefor China, with the use of life cycle assessment (LCA) method. The functional unit is pervehicle travel mileage of PHEV. The fuel consumption and environmental emission factors isacessed from the NEDC test and related documents. Based on this, we got the PHEV fuelcycle energy consumption, regulated air emissions (VOC, CO, NOx, PM10, SO2) andgreenhouse gas emissions (GHG). Then we evaluated effects of the power structure on theseindicators, and compared the fuel cycle of PHEV with conventional gasoline internalcombustion engine vehicle (ICEV) and compressed natural gas vehicle (CNGV). Theconclusions are as follows:(1) Compared with the state-of-the-art technology ICEV, PHEV in road trafficbackground can reduce40.7%fuel consumption, and reduce the emissions of VOC, NOx,SO2and GHG31.5%,15.2%,66.7%and55.8%respectively, which has a great significancein alleviating the increasingly serious urban air pollution.(2) Compared with the ICEV, the advantage of PHEV is not only in the energyconsumption and emissions of vehicle stage, but also in the entire fuel cycle energyconsumption and greenhouse gas emissions. From an energy perspective, the PHEV fuelcycle total energy consumption is56.3%lower than ICEV, among which the PHEV fuelcycle crude oil consumption is56.4%lower than ICEV. Due to more than50%ofdependence on imported crude oil, the scale applications of the PHEV can play the role of"power (or coal) instead of oil" to ease the pressure of China’s oil shortage, and is conduciveto solve the China’s energy security problems. From the perspective of environmentalemissions, the regulated air emissions of PHEV are reduced significantly compared with the ICEV. Emissions of VOC, NOx, SO2, PM10and CO for PHEV were reduced by41.5%,49.5%,56.0%,20.7%and7.9%respectively.Among the greenhouse gases, the N2O, CH4and CO2emissions of PHEV is6.5%,55.9%, and56.3%lower than ICEV’s. Meanwhileenvironmental emissions of PHEV have a trend to focus on the upstream stages, which isconducive to centralized treatment of pollutants.(3) Compared with the CNGV, PHEV has obvious advantages in total energyconsumption and greenhouse gas emissions. The fuel cycle energy consumption and GHG ofPHEV is54.0%and46.7%lower than the CNG’s.(4) The key of the optimization of the PHEV’s indicators is improving the energyconversion efficiency of power plants and reducing greenhouse gas emissions power plants.At the same time, reducing the proportion of coal-fired electricity can help to reduce theenergy consumption and greenhouse gas emissions. This method is more obvious for thePHEV than the ICEV.In summary, the PHEV fuel-cycle analysis showed that the phev can not only improveurban air pollution, and can significantly reduce oil consumption. The advantages andpotentials of PHEV is worthy of recognition, the government should formulate policies andmeasures to give great support.