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1.
In many cities, diesel buses are being replaced by electric buses with the aim of reducing local emissions and thus improving air quality. The protection of the environment and the health of the population is the highest priority of our society. For the transport companies that operate these buses, not only ecological issues but also economic issues are of great importance. Due to the high purchase costs of electric buses compared to conventional buses, operators are forced to use electric vehicles in a targeted manner in order to ensure amortization over the service life of the vehicles. A compromise between ecology and economy must be found in order to both protect the environment and ensure economical operation of the buses.In this study, we present a new methodology for optimizing the vehicles’ charging time as a function of the parameters CO2eq emissions and electricity costs. Based on recorded driving profiles in daily bus operation, the energy demands of conventional and electric buses are calculated for the passenger transportation in the city of Aachen in 2017. Different charging scenarios are defined to analyze the influence of the temporal variability of CO2eq intensity and electricity price on the environmental impact and economy of the bus. For every individual day of a year, charging periods with the lowest and highest costs and emissions are identified and recommendations for daily bus operation are made. To enable both the ecological and economical operation of the bus, the parameters of electricity price and CO2 are weighted differently, and several charging periods are proposed, taking into account the priorities previously set. A sensitivity analysis is carried out to evaluate the influence of selected parameters and to derive recommendations for improving the ecological and economic balance of the battery-powered electric vehicle.In all scenarios, the optimization of the charging period results in energy cost savings of a maximum of 13.6% compared to charging at a fixed electricity price. The savings potential of CO2eq emissions is similar, at 14.9%. From an economic point of view, charging between 2 a.m. and 4 a.m. results in the lowest energy costs on average. The CO2eq intensity is also low in this period, but midday charging leads to the largest savings in CO2eq emissions. From a life cycle perspective, the electric bus is not economically competitive with the conventional bus. However, from an ecological point of view, the electric bus saves on average 37.5% CO2eq emissions over its service life compared to the diesel bus. The reduction potential is maximized if the electric vehicle exclusively consumes electricity from solar and wind power. 相似文献
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不同水文组合对长江口南港流场的影响 总被引:3,自引:0,他引:3
长江口南港河段流场受径流、潮流、地形及风浪的影响,相当复杂。现场资料耗资巨大,且水文条件差别较大,模型进行了12种不同水文组合的试验,以弥补现场资料的不足。根据试验结果对南港河段水位、流量、流速的变化规律进行了研究,同时分析了南港的流场特征。 相似文献
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讨论了北部湾边际油田-WZ11-1N油田开发的工程策略,通过技术和经济上的综合分析,WZ11-1N油田采用了“三一”模式依托开发的成果,在应用涠洲地区成熟的、较先进的工程技术和开发经验的基础上,对依托平台/管线的处理工艺和寿命进行了详细的优化和校核,同时采用了电力组网新技术,达到了降低工程投资,提高油田收益的目的。另外在总体布置上为未来油田的依托开发预留了空间。 相似文献
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梁湘湘 《电力机车与城轨车辆》2004,27(5):48-50
变压器线圈制造过程中经常出现换位(组合)导线有股间短路现象,如何查找短路点并且有效地排除故障显得很重要。本文介绍目前常用的几种短路点的查找和排除方法。 相似文献
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江苏太仓杨林塘大桥为鱼腹式单肋拱梁组合桥,其造型美观,受力复杂,对其进行稳定分析十分必要。采用midas程序,建立了有限元计算模型,并对其进行了稳定性分析,对计算结果进行分析,得到一些重要理论。对该类桥梁的建设具有一定的借鉴作用。 相似文献
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在分析双电感半桥电路的基础上,提出了一种基于改进半桥拓扑结构的新型有源电力滤波器,它消除了传统有源滤波器拓扑的桥臂直通故障隐患,且具有可高频、高效率运行的优点。文章详细分析了其工作原理,给出了相应的控制策略。仿真和实验结果验证了这种新型有源滤波器的可行性。 相似文献