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• The improved ecological network analysis emphasizes both upstream and downstream of urban energy metabolic system. • Environ analysis and Ascendency analysis are integrated to analyze the processes and stability of urban energy metabolic system. • Beijing's 2007–2016 energy statistics are applied to reflect the transformation of Beijing's energy metabolic pattern. • Beijing's energy system has been improved through optimization both in supply and demand sides, with stability and risk resistance increased. In this paper, the improved ecological network analysis framework is applied to study the internal metabolic process and external stability of the urban energy metabolism system. Firstly, based on the analysis of ecological network, the sectors are selected from the three stages of urban energy production, transformation and consumption to build an ecological network model. Then, according to the metabolic process and stability characteristics of urban energy system, the Network Environ Analysis and Ascendency are integrated, and the time dimension is expanded. Finally, the data of Beijing from 2007 to 2016 are selected for empirical study. The results show that: (1) the cumulative consumption of raw coal and coal products and natural gas has changed significantly, the former has decreased from 3448×104 tce to 1283×104 tce, and the latter has increased from 560 ×104 tce to 3699×104 tce; (2) the electricity, heat and water production and supply sector consumed the most energy; (3) the energy transfer pathways between sectors has changed significantly. The results of stability analysis show that the overall stability of Beijing's energy metabolism system is increasing year by year, but there is still space for further improvement. This provides an important reference for optimizing the energy utilization structure of Beijing in the future and further promoting clean energy initiatives. [ABSTRACT FROM AUTHOR]

The resource shortages and environmental problems that cities face can be attributed to their increasing metabolic throughflow and their metabolic inefficiency. To support urban ecological management, it is necessary to identify the main metabolic actors responsible for these problems and analyze the characteristics of their metabolic structure. In this paper, we divide a typical urban metabolic system into seven components. Using material-flow analysis, we accounted for the amounts of resources and wastes transferred among the system''s components and between the system and its environment, using Beijing from 1998 to 2007 as a case study. We used four indicators (metabolic scale, intensity, efficiency, and impact) to represent the inner structural characteristics of the urban metabolic system and analyzed the system based on the proposed indicators. The results provide scientific support for identifying the key metabolic actors responsible for urban metabolic disorders by accurately characterizing the city''s metabolic status. [Copyright &y& Elsevier]