How much are electric vehicles driven?

The prospect for electric vehicles as a climate change solution hinges on their ability to reduce gasoline consumption. But this depends on how many miles electric vehicles are driven and on how many miles would have otherwise been driven in gasoline-powered vehicles. Using newly-available U.S. nationally representative data, this paper finds that electric vehicles are driven considerably fewer miles per year on average than gasoline-powered vehicles. The difference is highly statistically significant and holds for both all-electric and plug-in hybrid vehicles, for both single- and multiple-vehicle households, and both inside and outside California. The paper discusses potential explanations and policy implications. Overall, the evidence suggests that today’s electric vehicles imply smaller environmental benefits than previously believed.     

重载交通柔性路面结构设计研究与应用

车辆超载是一个普遍存在的问题,对道路路面的正常使用具有很大影响,是道路路面使用初期产生严重破坏的主要原因.结合深南路的路面修缮工程,分析重载交通柔性路面结构修缮所面临的实际问题.     

Dually sustainable urban mobility option: Shared-taxi operations with electric vehicles

Electric vehicles (EVs) are energy efficient and often presented as a zero-emission transport mode to achieve long-term decarbonization visions in the transport sector. The implementation of a sustainable transportation environment through EV utilization, however, requires the addressing of certain cost and environmental concerns such as limited driving range and battery-charging issues before its full potential can be realized. Nevertheless, a specific type of use of EVs, namely in taxi services, may elicit positive public opinion, as it promises a commitment toward sustainability in urban life. In light of this, this study proposes an integrated approach that combines EV operation with a conceptual design for shared-ride taxi services. As some productivity loss may be naturally expected due to the time spent in charging, it is important to look at whether such performance loss from the passenger and system standpoints can be offset with ingenuity in operational design. In this study, an EV taxi charge-replenishing scheme that can be coupled with a real-time taxi-dispatch algorithm is designed. The proposed EV charging schemes for taxi services are studied via simulations and the effects of the limited driving range and battery-charging details are examined from a system performance viewpoint. The simulation study also reveals illustrative results on the impact of the EV taxi fleet's operation on the charging system. Next, a real-time shared-taxi operation scheme that allows ride sharing with other passengers is proposed to maximize the operational efficiency. The simulation results suggest that the shared-taxi concept can be a viable option to improve on the limitations caused by EV operation. In addition, the importance of projected charging demands and queue delays at different charging locations are also addressed. Some limitations and a future research agenda are also discussed.     

Business strategies and the transition to low‐carbon cities

Cities are key drivers of global climate change, with the majority of greenhouse gas (GHG) emissions being tied to urban life. Local actions to mitigate and adapt to climate change are essential for stabilization of the global climate and can also help to address other urban ecological problems such as pollution, decreasing biodiversity, etc. Companies are important urban actors in the development of low‐carbon cities because they provide a multitude of goods and services to city populations and directly influence urban carbon dioxide (CO₂) emissions. This is a new area of research. While studies on corporate sustainability are numerous, there is little, if any, existing research that examines the role of companies in climate change adaptation and mitigation within specific urban areas. Urban ecologists also have not examined how corporate activity affects urban systems. Taking a multi‐disciplinary systems approach, we present a conceptual model of the role of companies in managing urban interactions with the climate system. We also present empirical findings illustrating how one company ‘partners’ with the city of Rotterdam to test electric vehicles as a pilot project for urban climate adaptation and mitigation. Copyright © 2010 John Wiley & Sons, Ltd and ERP Environment.     

A heuristic approach for the green vehicle routing problem with multiple technologies and partial recharges

This paper presents several heuristics for a variation of the vehicle routing problem in which the transportation fleet is composed of electric vehicles with limited autonomy in need for recharge during their duties. In addition to the routing plan, the amount of energy recharged and the technology used must also be determined. Constructive and local search heuristics are proposed, which are exploited within a non deterministic Simulated Annealing framework. Extensive computational results on varying instances are reported, evaluating the performance of the proposed algorithms and analyzing the distinctive elements of the problem (size, geographical configuration, recharge stations, autonomy, technologies, etc.).     

道路车辆电器及电子设备供电环境条件标准的抛负载试验剖析

新版ISO标准已将车载电器及电子设备的抛负载瞬间脉冲试验归人道路车辆电器电子的供电环境条件和试验范畴。本文通过介绍一些标准起草中的技术背景和标准文字中的未尽之言，以及一些试验实践中应予把握的要点，从而对于国家标准的制定、相关榆测部门的检测能力提升，以及车辆电器及电子设备品质的监控质量的提升有所帮助。     

油田压裂施工车辆的安全管理

施工车辆是油田压裂施工中不可或缺的一部分,特别是主体泵车、混砂车、仪表车等车辆更是压裂作业中重要的配套设备,车辆安全管理的效果能够直接影响油田井下作业的效率和安全。因此对油田压裂施工车辆的安全管理是井下公司势在必行的措施。     

道路运输行业面向节能减排的I/M制度检测方法研究

I/M制度是保证汽车处于良好的技术状况,投资最少、最有效、最根本的途径。文章介绍了适用于我国道路运输行业现状的I/M制度在实施时所能采用的检测方法。并且对这些检测方法进行了详细的分析及比较。     

低碳经济视野下的新能源汽车发展战略

低碳经济的核心是能源技术和减排技术创新、产业结构和制度创新以及人类生存发展观念的根本性转变。石油能源供给与汽车产业发展的矛盾将日益凸显,新能源汽车发展是涉及国家能源战略的重大问题。我国应创新商业模式,建立产业联盟,加强创新网络组织和消费者导向的盈利模式的构建,加大对新能源汽车行业的政策扶持。     

新能源汽车价格补贴政策的绩效分析和改善建议--以J新能源汽车公司为例

新能源汽车是我国汽车行业重要的发展方向,笔者通过研究我国新能源汽车的发展历程、价格补贴政策存在的问题,提出完善新能源汽车价格补贴政策的对策,以期为我国新能源产业的科学发展和我国汽车产业的转型升级提供参考。