Today both the economic growth and expansion of urbanization have increased community access to private cars. Thus, the urban transportation has become a critical part of energy consumption and greenhouse gas emissions. The excessive dependence of urban transportation on high-emission fuels is the main obstacle to develop a low-carbon transport. Meanwhile, natural gas is a bridge fuel to develop a low-emission transport. To the best of our knowledge, there has been little attention towards the association between the development of natural gas-fueled vehicles and the CO2 emission. Therefore, the problem we studied is the role of compressed natural gas (CNG) vehicles in replacing high-emission fuels. In this study, we aimed to study this association by selecting the system dynamics approach due to the complexities of the social-economic system of transportation. In this modeling, different subsystems of the transport fleet were employed including CNG vehicles and urban transportation subsystems. Iran has used CNG as an alternative fuel in the transportation sector, making it one of the three leading countries in the use of natural gas in the urban transportation system. Our case study is focused on Tehran, which is the capital and the largest city of Iran.

中文翻译：

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开发用于低碳城市交通的CNG车辆的系统动力学方法：案例研究

今天，经济增长和城市化的扩大都增加了社区使用私家车的机会。因此，城市交通已成为能源消耗和温室气体排放的关键部分。城市交通对高排放燃料的过度依赖是发展低碳交通的主要障碍。同时，天然气是发展低排放运输的桥梁燃料。据我们所知，很少有人关注天然气燃料汽车的发展与二氧化碳排放之间的关系。因此，我们研究的问题是压缩天然气（CNG）车辆在替代高排放燃料方面的作用。在这项研究中，由于运输的社会经济系统的复杂性，我们旨在通过选择系统动力学方法来研究这种关联。在此模型中，使用了运输车队的不同子系统，包括CNG车辆和城市运输子系统。伊朗已在交通运输部门使用压缩天然气作为替代燃料，使其成为城市交通运输系统中天然气使用的三个领先国家之一。我们的案例研究的重点是德黑兰，它是伊朗的首都和最大的城市。使其成为城市交通系统中使用天然气的三个领先国家之一。我们的案例研究的重点是德黑兰，它是伊朗的首都和最大的城市。使其成为城市交通系统中使用天然气的三个领先国家之一。我们的案例研究的重点是德黑兰，它是伊朗的首都和最大的城市。