Optimizing flexibility and low-carbon emissions in integrated energy systems: A two-stage robust optimization model incorporating hydrogen and carbon trading

Abstract

Source-load output uncertainty poses significant risks to the stable operation of Integrated Energy Systems (IESs). To ensure safe and stable system operation while optimizing the balance among robustness, economic viability, and low-carbon emissions, this paper presents a two-stage robust optimal scheduling model for IESs. This model is supported by hydrogen-containing electric dual-energy conversion characteristics under source-load uncertainty. Additionally, to promote the low-carbon characteristics of the system, a ladder carbon trading mechanism is introduced on the source side of the carbon source equipment. Furthermore, the integration of hydrogen energy enhances the clean characteristics of source-side multi-energy coupling. The proposed utilization mode, Power-to-Hydrogen, Hydrogen-to-Power, Hydrogen Energy Storage, and Hydrogen Load (P2H-H2P-HES-HL), allows for bidirectional conversion, thereby increasing the flexibility and responsiveness of overall system scheduling. Finally, to ensure that the model closely reflects actual operational and scheduling conditions, a two-phase robust approach is employed to address source-load uncertainties. This approach is solved iteratively using the linear transformation of the Karush-Kuhn-Tucker (KKT) conditions and the Column-and-Constraint Generation (C&CG) algorithm. The results demonstrate that the proposed model significantly enhances the scheduling capability of the system in coping with uncertainty, thereby effectively ensuring its flexibility and security.