Low-Carbon Economic Scheduling of Hydrogen-Integrated Energy Systems with Enhanced Bilateral Supply–Demand Response Considering Vehicle to Grid Under Power-to-Gas–Carbon Capture System Coupling

Hydrogen-Integrated energy systems (HIESs) are pivotal in driving the transition to a low-carbon energy structure in China. This paper proposes a low-carbon economic scheduling strategy to improve the operational efficiency and reduce the carbon emissions of HIESs. The approach begins with the implementation of a stepwise carbon trading framework to limit the carbon output of the system. This is followed by the development of a joint operational model that combines hydrogen energy use and carbon capture. To improve the energy supply flexibility of HIESs, modifications to the conventional combined heat and power (CHP) unit are made by incorporating a waste heat boiler and an organic Rankine cycle. This results in a flexible CHP response model capable of adjusting both electricity and heat outputs. Furthermore, a comprehensive demand response model is designed to optimize the flexible capacities of electric and thermal loads, thereby enhancing demand-side responsiveness. The integration of electric vehicles (EVs) into the system is analyzed with respect to their energy consumption patterns and dispatch capabilities, which improves their potential for flexible scheduling and enables an optimized synergy between the demand-side flexibility and system operations. Finally, a low-carbon economic scheduling model for the HIES is developed with the objective of minimizing system costs. The results show that the proposed scheduling method effectively enhances the economy, low-carbon performance, and flexibility of HIES operation while promoting clean energy consumption, deep decarbonization of the system, and the synergistic complementarity of flexible supply–demand resources. In the broader context of expanding clean energy and growing EV adoption, this study demonstrates the potential of energy-saving, emissionreduction systems and vehicle-to-grid (V2G) strategies to contribute to the sustainable and green development of the energy sector.