Research On Environmental Benefit Of Electric Vehicle Based On Coal-fired Electricity's Life Cycle

The promotion of electric vehicles is regarded as the main way to solve the current emission problems in the field of transportation,and the electric vehicle industry has been strongly supported by the government.In the background of energy structure based on coal-fired electricity in China,the use of electricity instead of fuel in electric vehicles is essentially the emission transferring from the consumption to the production.Therefore,it is necessary to study the emission of the use phase of electric vehicles.The environmental benefits of electric vehicles replacing traditional fuel vehicles are compared in order to clarify the practical significance of electric vehicles to the sustainable development of traffic field.A full life cycle analysis of the production,transportation and combustion for power generation was conducted based on the angle of coal-fired electricity chain.The hybrid life cycle assessment method was used to measure the energy consumption and emissions of all sectors,so as to obtain the life cycle emission inventory of coal-fired electricity chain and analyze the contribution of each phase to emissions.According to the life cycle emission inventory of fuel,the battery electric vehicle and plug-in hybrid electric vehicle were taken as the research object.The emission reduction effect of two kinds of electric vehicles instead of traditional fuel vehicles was analyzed,and the environmental impact and environmental cost of the emissions were quantified.Combined with the regional power structure,the field environmental benefits of electric vehicles were weighted and analyzed.The research found:(1)Under the current power structure,the two electric vehicles can reduce carbon emissions and partial pollutants emissions except for nitrogen oxides in the use phase.(2)The environmental cost of battery electric vehicle mileage is the least,followed by plug-in hybrid electric vehicle,and electric vehicle instead of traditional fuel vehicle driving had a positive impact on the ecological environment.(3)With the gradual improvement of the energy structure and the gradual improvement of the power cleanliness,the environmental benefits of electric vehicles have great potential for upgrading.(4)The environmental benefits of electric vehicles vary significantly across the country.The best environmental benefits can be achieved in the south China grid area,while the worst environmental benefits can be obtained in the northeast power grid area.In this thesis,it was proved that the environmental benefit of the electric vehicle was better than that of the traditional fuel vehicle by establishing a life cycle assessment model of coal-fired electricity which meets the national conditions.The optimization measures,such as improving the energy structure,upgrading the power generation technology and the transmission efficiency of the power grid,were also proposed to increase the environmental benefits of electric vehicles.Finally,the research results of the weighted analysis of the regional empirical power cleanliness can provide reference and suggestions for the formulation of the subsidy policy for electric vehicles.