Optimization of Low-Carbon Scheduling for Integrated Energy Systems Considering Green Certificates and Carbon Trading Mechanisms

This paper presents a bi-level optimal scheduling method for the integrated energy system (IES). The upper level addresses the economic dispatch of the power grid and gas network, while the lower level focuses on the low-carbon economic dispatch of IES, incorporating demand response. By analyzing the operational mechanisms of the carbon emission trading (CET) and green certificate trading (GCT) markets, separate CET and GCT models are developed. Additionally, a CET-GCT coordination mechanism is designed to minimize the carbon trading costs for the IES. To avoid local optimization in the model's solution process, a two-dimensional sigmoid function is introduced to smooth the variables. Simulation results demonstrate that the proposed method effectively reduces carbon emissions, mitigates curtailment of renewable energy, and enables the low-carbon economic operation of the integrated energy system.