考虑车型差异影响的乘用车车身生命周期评价

Life cycle assessment of passenger car body considering vehicle model variations

尽管汽车轻量化能够有效降低使用阶段的环境影响,但在全生命周期包括原材料获取、制造及装配、运输、运行使用以及回收的考虑下,轻量化并不一定能达到节能减排的效果.针对此问题,本文建立了包含乘用车各个阶段生命周期评价模型,在考虑车型差异的基础上,采集奇瑞公司的4款微型车及市面上销量较大的4款紧凑型和4款中大型车车身,分别进行了生命周期评价,分析其化石能源消耗、矿产资源消耗及环境排放.清单分析结果表明:①在当前我国电力结构下,铝制车身在全生命周期内具有较大的优势,主要体现在制造装配及运行使用阶段,而钢制车身在原材料获取阶段表现出较低的能耗和环境排放;②对于采用不同的动力系统的车身而言,在设定的功能单位行驶里程内,纯电动汽车仅在化石能源消耗方面优于内燃机汽车.在上述结果的基础上,重点讨论了在未来电力结构的变化、行驶里程增加及回收处理过程优化的3种情境下12种车身的环境影响变化,铝制车身和电动汽车在环境影响方面的优势会更加凸显.本研究有助于为我国汽车生产企业及其上下游产业链条面向碳中和的产品绿色设计及碳足迹降低提供借鉴.

It is well known that lightweight vehicles can effectively reduce the environmental impact in the use phase,but they may not achieve energy saving and emission reduction under the consideration of the whole life cycle.To address this issue,this paper established a life cycle assessment model for passenger cars,and the fossil energy consumption,mineral resource consumption,and environmental emissions were analyzed.The phases of raw material acquisition,manufacturing and assembly,transportation,use,and recycling were considered in a whole life cycle.The assessment selected and compared four micro cars from Chery Company,four compact,and four medium-large cars with large market shares.Results of inventory analysis show that:①Under the current power structure in China,the aluminum body has a significant advantage in the whole life cycle,while the steel body has lower energy consumption and environmental emissions in the raw material acquisition stage.②For car bodies with different power systems,electric vehicles only have an advantage over fuel vehicles in terms of fossil energy consumption within the set functional unit mileage.Moreover,the environmental impact changes of the abovementioned 12 types of bodies under three scenarios of future power structure change,mileage increase and recycling process optimization were discussed.The advantages of aluminum bodies and electric vehicles in terms of environmental impacts will become more prominent.This study assists in providing a reference for green design and carbon footprint reduction for China's automobile manufacturers.