Hybrid Emergy-LCA (HEML) based metabolic evaluation of urban residential areas: The case of Beijing, China

In this paper, metabolic evaluation has been employed for better understanding the trends in urban environmental changes. Due to the urban activities cause impacts not only on local level but also a broader scale, Hybrid Emergy-LCA (HEML), a combining approach of Emergy Analysis (EMA) and Life Cycle Assessment (LCA) is structured to quantitatively investigate the mechanism. For the similarity across many emerging cities in China, a large-scale sub-urban residential area named Tian Tongyuan (TTY) in Beijing was chosen for testing the HEML. Objective indicators of live quality and negative impacts are both considered. Analysis indicates that the household Emergy input of TTY is 1.76E+16 sej/yr, while the prominent environmental impact is induced by Photochemical Oxidant Creation Potentials (POCP), 4.58E+05 g ethane eq./yr. The sustainable performance constructed by its live quality and environmental impacts of TTY is found as 98.80% as that of Beijing average. Mitigation polices on the building sector should be proposed because of its dominating impacts among various consuming ends of energy and materials.