Optimised Scheduling of Integrated Energy System Considering Hybrid Electrolyser Hydrogen Production and Refined Hydrogen Utilisation

Addressing climate change, resource depletion and environmental degradation driven by fossil fuel dependence requires urgent development of sustainable energy systems. Virtual power plant (VPP) enhance economic performance and grid flexibility by aggregating distributed resources and flexible loads. Building on this concept, this study proposes a hydrogen park-level integrated energy system (H-PIES) under the VPP framework, incorporating user-side demand response (DR) and a tiered carbon trading mechanism for low-carbon, efficient energy management. First, a hybrid strategy combining alkaline electrolyzers (AEL) and proton exchange membrane electrolyzers (PEMEL) is proposed for power-to-gas (P2G) applications, considering hot/cold starts and load range limitations to maximise renewable energy utilisation. Second, a multi-dimensional flexible load response model is also introduced to enhance operational flexibility. Last, the tiered carbon trading mechanism is embedded into the objective function to incentivise low-carbon transitions. Simulation results indicate that the refined hydrogen utilisation strategy and hybrid electrolyser operation mode effectively accommodate renewable energy output, reducing total costs by 0.28% and 0.65%, respectively, compared to using only AEL or PEMEL. The tiered carbon trading mechanism effectively curbs emissions, whereas DR reduces system costs and emissions by 4.15% and 9.50%, respectively, and smooths load profiles, promoting overall system sustainability.