TY - EJOU AU - Sun, Yansen AU - Ding, Yi AU - Cui, Hualei AU - Hui, Yuanchao AU - He, Yupeng TI - Optimal Scheduling of Integrated Energy Systems with P2G-CCS Coupling and Hydrogen-Blended Natural Gas under Tiered Carbon Trading T2 - Energy Engineering PY - VL - IS - SN - 1546-0118 AB - Integrated energy systems (IES) are pivotal for achieving low-carbon transitions, yet their optimization under carbon constraints remains challenging. This paper proposes an optimal scheduling model for IES that synergistically combines power-to-gas coupled with carbon capture systems (P2G-CCS) and hydrogen-blended natural gas under a tiered carbon trading mechanism. The model innovatively refines the P2G process into two stages (electrolysis and methanation), utilizing methanation reaction heat to enhance efficiency. It further incorporates hydrogen blending into gas turbines and boilers and implements a tiered carbon trading mechanism to constrain emissions. The objective is to minimize total costs, including carbon trading, fuel procurement, carbon capture, unit cycling, and wind curtailment penalties. The model is linearized and solved using MATLAB/YALMIP with the CPLEX solver. Comparative simulation results demonstrate the significant advantages of the proposed strategy: it reduces the total operating cost by 7.69%, cuts carbon emissions by 7.3%, and lowers wind curtailment costs by 20.16% compared to a uniform carbon trading benchmark. Furthermore, analysis of hydrogen blending ratios reveals that a dynamic blending strategy can reduce gas turbine output and electrolysis power consumption by 6.88% and 20.93%, respectively, compared to a fixed-ratio approach. The study confirms that the deep coupling of P2G-CCS, flexible hydrogen utilization, and the tiered carbon market collectively enhance the low-carbon economic performance of IES. KW - Integrated energy system; P2G-CCS; hydrogen blending in natural gas; tiered carbon trading DO - 10.32604/ee.2025.072860