Energy Flow Analysis Of Infrastructure Ecosystem

Rapid urbanization brings about economic development and social progress,as well as many bad effects,such as massive energy consumption.To maintain the stable operation of the city and meet people's needs,it is necessary to vigorously promote new urbanization and cities' healthy and sustainable development.Infrastructure system is the basic structure of city,and society cannot work well without it.Sustainable urban infrastructure design must be based on a good understanding of the interaction among urban infrastructures.Therefore,it is vital to explore the internal links of urban infrastructure systems.In this study,the composition of infrastructure ecosystem is determined by collecting and sorting out relevant academic materials,and the calculation methods of embodied energy and exergy of infrastructure system are established.Beijing is chosen as a case study to contrast the two methods.The results show that embodied energy and exergy of infrastructure ecosystem in Beijing are 823.15 PJ and4662.PJ,respectively.Eleven kinds of infrastructure can be divided into three categories.They play different roles in the energy transfer network of infrastructure ecosystem.Power facilities,oil and gas production facilities and water supply and drainage facilities are producers of urban infrastructure ecosystems.Transportation facilities and information and communication facilities are the energy transmission media in urban infrastructure system.Financial facilities,environmental protection facilities,educational facilities,health and social work facilities,recreational facilities and public management facilities are consumers.Energy flow ecological network of Beijing infrastructure ecosystem is a highly competitive network,and all infrastructures are related with each other,at least indirectly.However,different energy calculation methods will greatly affect the utility relationship between specific infrastructures.Through application,it is found that embodied energy calculation method is suitable for the calculation of energy flow in smaller scale,because of data accessibility and calculation simplicity.Although exergy calculation method extends the definition of "energy",it is not suitable for the analysis of energy flow on a smaller scale because of complicated calculation.