Research On The Life Cycle Environmental Impact Of New Energy Vehicles Under The New Technology Revolution

At present,mankind is faced with a series of serious global environmental problems such as global warming,energy crisis and ecological destruction.The contribution of new energy vehicles in saving energy and reducing pollution emissions can improve and alleviate such problems,so we have given great attention to new energy vehicles.This study is based on the development of new energy vehicles in China’s local conditions.In order to explore the impact trend of new technology revolution on the environmental load of new energy vehicles in their full life cycle,basic scenario construction and dynamic life cycle analysis are carried out for new energy vehicles equipped with different battery technologies.Firstly,in order to compare and analyze the emission reduction degree of new energy vehicles in their life cycle,the GREET 2020 model is adopted in this paper to construct the life cycle evaluation model for new energy vehicles with common characteristics.Four models of traditional fuel vehicle ICEV,hybrid vehicle HEV,plug-in hybrid vehicle PHEV and electric vehicle BEV are analyzed.Among them,the power battery of HEV is nickel-metal hydride battery（Ni-MH）,the power battery of PHEV is ternary lithium battery（NMC）,and the power battery of BEV is lithium iron phosphate（LFP）,ternary lithium battery（NMC）and lithium manganese ate（LMO）.A total of six models are discussed and analyzed.After determining the purpose and scope of the research,the fuel cycle and vehicle cycle of the life cycle of new energy vehicles are modeled and analyzed,and the results of the life cycle evaluation list of the six types of vehicles are as follows:The total energy consumption reduction degree of new energy vehicles on ICEV is 25.4%for HEV,27.9%for PHEV and 38.3%～42.9%for BEV,respectively.Among them,the secondary energy power production in the WTP stage consumes more energy,but in the PTW stage,because of the improvement of fuel economy of new energy vehicles,the energy consumption in this stage is less.Environmental pollution emissions,especially greenhouse gas emissions,the emission reduction degree of new energy vehicles on ICEV was 25.7%for HEV,22.7%for PHEV and 34.3%～35.0%for BEV.New energy vehicles have increased emissions of SO_X and particulate pollution.Through the characteristic analysis of the end point type,normalization processing and importance ranking and weighting processing of the list data results,it is obtained that the environmental impact of new energy vehicles has different reduction potential in the environmental load of GWP,ADP,HTP and POCP.It can alleviate environmental problems such as global warming,resource and energy depletion,human biological toxicity,photochemical smog and so on.The comprehensive environmental impact of new energy vehicles on the whole life cycle is smaller than that of ICEV.The life cycle assessment results of new energy vehicles can be used as the environmental benefit evaluation index in the comprehensive benefit analysis of battery technology,and can also be used as the basis of dynamic life cycle assessment when exploring the environmental impact of life cycle of new energy vehicles in the future scientific and technological environment.Secondly,in order to put forward the development direction of the technological innovation of power battery technology,this study evaluated the comprehensive benefits of battery technology application from four aspects:economic benefits,social benefits,product efficiency and environmental benefits.Through the method of hierarchy analysis,the 28 indexes of four aspects were sorted,and it was found that the indexes of quality efficiency and consistency had the greatest influence on the comprehensive benefit,and it was proposed to strengthen the battery production link to improve the performance as an effective means to improve the comprehensive benefit of the battery.It is also identified that the index weights of global warming potential and fossil resource consumption potential are relatively large,so it is necessary to improve the environmental pollution in production,use,scrap recycling and other links,and enhance the comprehensive benefits.Finally,in order to explore the impact trend of new technology revolution on the environmental load of new energy vehicles’life cycle,this paper analyzes the future technological environment of two key parameters,electric power structure and production materials,and makes dynamic analysis of new energy vehicles’life cycle model through three scenario assumptions and predictions.To support the data of carbon peak,this paper focuses on the study of GHGs equivalent to greenhouse gas emissions.The power structure adjusts the ratio of thermal power by 10%in the basic scene.The calculation results show that the influence of this key parameter change on ICEV and HEV is little,while the influence degree of BEV is greater than that of PHEV,and the influence degree S_BEV=0.8580>S_PHEV=0.5081.In terms of production materials,the research on the upgrading of production materials and the lightening of materials is carried out.By adjusting the proportion of vehicle body mass by 5%respectively,it is calculated that the influence of material reduction on GHGS emission is closely related to the mass base,and the degree of lightening emission reduction is large in the case of large mass.However,the scenario hypothesis also needs to consider the actual use situation,and the lightweight degree of the vehicle is limited,so it should be discussed within a reasonable range.