In the Context of Staircase Carbon Trading, Integrated Energy Optimization Scheduling Considering Two-Stage P2G-CCS

Under the dual-carbon background, optimization of integrated energy systems is chiefly concerned with the two-stage power-to-gas (P2G) process as well as the blending of hydrogen with gases. By breaking down P2G into electrolysis hydrogen production (P2H) and methanation stages, and combining carbon capture and storage (CCS) with hydrogen blending in gas equipment, a coordinated operation framework is constructed. The two-stage P2G achieves multi-level utilization of hydrogen and recovery of reaction heat. CCS captures CO<inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</inf> for methanation to form a carbon cycle, and hydrogen blending in gas turbines and boilers reduces combustion carbon emissions. Case studies show that the coupling of two-stage P2G-CCS reduces carbon emissions, and flexible hydrogen blending costs less than fixed modes. Step carbon trading, through base price thresholds and price growth rates, promotes stable system carbon emissions. Base prices that are too high or too low will weaken sensitivity. The research confirms that multi-energy complementarity, carbon cycles, and policy incentives can enhance energy utilization, balance emission reduction costs, and provide theoretical and technical support for low-carbon transformation of parks and virtual power plants.