A Coupled Coordination Model to Evaluate "Energy-Economy-Carbon Emission" Synergistic Development in Tianjin

Energy consumption is the driving force of urban economic development, but the carbon emissions brought by its combustion seriously limit the green and low-carbon transformation of cities. In this paper, a new coupled coordination model is proposed to evaluate the energy-economy-carbon emission synergistic development in the city. The model consists of two sub-models: the coupled degree evaluation model and the coordination degree evaluation model. The coupled degree evaluation model quantitatively describes the relationship between energy, economy, and carbon emission. The coordination degree evaluation model is used to evaluate the status or level of coordination of energy, economy, and carbon emission in developing a low-carbon city. Taking Tianjin as an example, a case study is conducted to demonstrate the effectiveness of the proposed model. The results show that the energy-economy-carbon synergy in Tianjin has gradually improved from a severe imbalance in the early 2000s to a moderate imbalance recently. Tianjin has achieved remarkable results in constructing a low-carbon city.