The Application Of Transport Energy Consumption In Green Urban Traffic Planning

With the process of rapid urbanization and motorization in China, the energy demand of urban transport system is corresponding increasing. Due to limited non-renewable energy sources, the conflict between urban population growth and the reduction of transport energy has been held back the sustainable development of urban transport system. In view of this, the energy saving in urban transport system has become the aim of "low-carbon city" planning. In this paper, influencing factors, energy demand forcast, urban spatial structure, urban traffic planning and the policies on energy saving are chose to research the relationship between urban trasport system and transport energy consumption, and the main of this paper includes the following aspects:(1) From the system point of view, the influencing factors of urban transport energy consumption could be classified by the macro-level (whole city), the meso-level (road network or community) and the micro-level (vehicle). In terms of the macro-level, urban spatial structure, city size and urban traffic structure are the main factors, in which urban spatial structure is the primary factor, city size is the important factor and urban traffic structure is the key factor. All the interrelated macro-level factors together determine the total energy consumption of urban transport traffic. Urban road network, accessibility and city micro-transportation circulation are the meso-level factors to urban transport energy consumption. With respect to the micro-level, the energy consumption of monomer vehicle is the leading factor.(2) Based on the existing forecasting models of transport energy demand, Gompertz model and Spread Sheet model are made up to forecast urban transport energy demand, and this associated model is applied to Chengdu city. In addition, for analyzing the impact of various factors upon transport energy demand in Chengdu city, the decomposable model is created. The results showed that in the past decade, the process of urbanization is the primary factor to the increase in transport energy consumption, and in the next decade, traffic structure and trip rate of mobility will affect the change of passenger transport energy demand in Chengdu city mainly.(3) In terms of single-center and multi-center, the impacts of urban spatial structure on resident trips and transport energy consumption are studied. Through a simple numerical example, the fact is that multi-central city is superior to single-center city in transport energy saving. Besides, the researches on complex land use and "compact city" show that the intensive development of urban land could help reduce transport energy consumption. Be based upon these concepts, the optimization model of urban land use is constructed. In the model, the objective function is to minimize the total travel time among communities, and the main restrictive condition is urban transport energy consumption. The result of the model is the proportion of various land functions under the guidance of mixed urban land use and reasonable transport energy consumption.(4) Sustainable transportation develpment, green transport system, low-carbon transport system and other related concepts are discussed. On the basis of this, transport energy consumption is introduced into urban traffic planning for creating the minimum energy consumption model of urban trasport system. Considering the capacity constraint of urban road network, the aim of this model is to solve the problem on the appropriate scale of conventional buses and cars. In addition, to encourage more residents travel by public transportation, the optimization model of urban traffic structure is established under the restrictive conditions of transport energy consumption, network resources, environment capacity and other constraints. This model is applied to analyze the reasonable urban traffic structure of Chongqing city in 2020.(5) In view of the characteristics, the classification and the development process of traffic policy, the dynamic modeling method is applied to evaluate urban transport energy saving policies. Firstly, the model forecasts transport energy consumption and CO2 emissions of Shanghai city in 2020. The forecasting results are set up as the base scenario, and the other three scenarios are got by three different groups of energy saving policies. After the scenarios are analyzed and compared, the results show that single energy saving policy will be difficult to achieve energy saving and emissions-reduction targets, and the different combined polices can be help to meet goals.This paper offers new ideas and methods for studing sustainable urban transport development under the energy constraints. In conclusion, to achieve the goal of green urban transport system, urban public transport should only be chosen as the leading traffic mode, the strategy of public transport first and the complex land use should be implemented in China. Only urban energy-saving traffic system could reduce the consumption of fuels and meet the demands of sustainable urban transport development.