近年来，在中国政府的支持下，电动汽车产业发展迅速，渗透率保持着逐年上升的趋势。因此有越来越多的学者开始关注电动汽车的普及会给社会带来的影响，主要的评估方向为电动汽车相对内燃机汽车的全生命周期成本和碳排放差距，但大部分研究都有模型边界或地区差异上的局限性。本研究在这些成果的基础上做了更多创新改进：一方面本研究扩大了评估边界并建立了中国的电动汽车全生命周期评估数据库，将电动汽车和内燃机汽车大多相关的环节都纳入了框架，比如基础设施建设、动力电池梯次利用及回收工艺分析等；另一方面本研究同时在中国多情景下评估了全生命周期成本和碳排放两个维度，从而可以进行成本有效性分析，不同情景也可以体现变化趋势。本研究的最终目的是要提供一个完整可靠的电动汽车成本和碳排放差距的评估结果，从而指出未来的优化路径。本研究首先针对中国电动汽车建立了一个成本和碳排放两个维度，制造、使用和回收三个阶段，正常行驶里程和低行驶里程两类情景，北京市驾驶循环和新标欧洲驾驶循环两类驾驶循环的全生命周期评估模型。然后在模型的基础上建立了中国电动汽车的全生命周期评估数据库，涵盖了大多数材料开采及生产加工工艺、驾驶循环参数、充电基础设施参数、动力电池梯次利用模式、回收再生工艺以及能源和物料的全生命周期碳排放系数等。最后，本研究对结果进行了成本有效性计算和未来提升路径分析。评估结果指出：第一，内燃机汽车的全生命周期成本一般比电动汽车低7%到25%之间，主要原因是目前动力电池生产成本过高，未来随着制造工艺成本的降低或者动力电池梯次利用的大规模应用可以有效改善这一情况，但也需要关注充电基础设施的成本上升问题；第二，内燃机汽车的全生命周期碳排放一般比电动汽车高26%到41%之间，电动汽车的这一优势主要依托于其在驾驶环节碳排放较低，但随着电力碳排放系数下降和内燃机汽车燃油经济性提升，这一优势会受到影响，因此未来更需要关注制造环节的碳排放，而电动汽车回收可以有效扩大这一优势；第三，电动汽车相对内燃机汽车的碳排放减免成本有效性一般低于1kg-CO2eq/元，也就是说通过电动汽车实现碳排放减免并不具备明显的成本有效性，电动汽车的价值实际上还应该从许多其他维度来评估，比如降低有害排放、提高能源安全度等，这可能是后续研究扩展的重点。
In recent years, electric vehicle industry has developed rapidly in China with the support of government, and the penetration rate has been increasing year by year. Many scholars begin to pay attention to the impacts of the popularity of electric vehicles. A series of life cycle assessments have been conducted on cost and Greenhouse Gas emissions of electric vehicles and internal combustion engine vehicles. However, most of the studies have limitations on model boundaries or regional differences. Based on existing results, this study has made more innovative improvements. First, this study has expanded the evaluation boundary and established the full life cycle evaluation database for electric vehicles in China, including most relevant issues such as infrastructure construction, traction battery pilot use and recycling technology analysis. Secondly, this study has evaluated the life cycle cost and Greenhouse Gas emissions under the same boundary for both electric vehicles and internal combustion engine vehicles in different scenarios of driving cycles and mileages. This study has deeply analyzed the cost effectiveness and trends by scenarios. The ultimate purpose is to provide complete, reliable and comparative evaluation results of the life cycle cost and Greenhouse Gas emissions between electric vehicles and internal combustion engine vehicles, and then point out the future path for improvement.In this study, a two-dimension (cost and Greenhouse Gas emission), three-stage (manufacturing, usage and recycling), two-mileage (general and low mileage), two-driving cycle (Beijing driving cycle and New European Driving Cycle) life cycle assessment model for electric vehicles was established. Then, the whole life cycle database of electric vehicles in China is established, including material mining and production processing technologies, driving cycles, charging infrastructures, traction battery pilot use, recycling and recovery technologies, and the life cycle Greenhouse Gas emission factors of energy and materials. Finally, this study has calculated the cost effectiveness and analyzed the potentials.The results show that the life cycle cost of an internal combustion engine vehicle is 7% to 25% lower than that of an electric vehicle, which is mainly due to the additional cost of traction battery. This situation can be effectively improved by the reduction of manufacturing cost or large-scale application of traction battery pilot use. It is also necessary to pay attention to the rising cost of charging infrastructures. On the other hand, the life cycle Greenhouse Gas emissions of an internal combustion engine vehicle are 26% to 41% higher than those of an electric vehicle. This advantage mainly depends on the lower emissions of electric vehicles in driving stage. However, although the Greenhouse Gas emission factor of electricity is decreasing, this advantage is still becoming smaller due to the fuel economy improvement of internal combustion engine vehicles. Therefore, more attention should be paid to the emissions of vehicle manufacturing in the future, and electric vehicle recycling can be an effective solution. The cost effectiveness of Greenhouse Gas emission reduction by electric vehicle is generally lower than 1kg-CO2eq/yuan. Therefore, there is no cost advantage to get Greenhouse Gas emission reduction through electric vehicles. In fact, the value of electric vehicles comes from many other dimensions as well, such as reducing harmful emissions and improving energy source security, which may be the focus of future researches.
