A bi-level optimization operation method for hydrogen-enriched integrated energy systems incorporating dynamic carbon emission factors

To address low-carbon economic dispatch challenges in integrated energy systems (IES) under dynamic carbon emission factors (CEFs), this study proposes a hierarchical bi-level optimization framework for hydrogen-enriched IES (H2-IES). The core innovation establishes an upper-level dynamic CEFs calculation framework based on carbon emission flow theory, enabling node-and-time-resolved carbon tracing to guide real-time energy pricing and market clearing. This framework dynamically quantifies carbon intensity in electricity/hydrogen procurement, reflecting temporal grid decarbonization variability and spatial energy conversion differences. The lower-level model employs a Stackelberg game with four stakeholders (producers, storage providers, users, retailers) to align energy activities with CEF-driven price signals. Two technical innovations enhance applicability: (1) a two-stage power-to-gas (P2G) process with adaptive hydrogen blending (5 %–20 %) for fuel flexibility, leveraging hydrogen/methane byproducts; (2) a P2G–CCS–CHP coupled system closing carbon loops via waste heat recovery, improving energy efficiency by 18.7 %. A dual-participant ladder carbon trading mechanism incentivizes collaboration by sharing carbon costs across consumption tiers, bridging technical optimization and behavioral adjustment. The multi-strategy enhanced dung beetle optimization algorithm (IDBOA) achieves 40 % faster computation than conventional methods. Case studies show the framework reduces total carbon emissions from 12.72 to 7.06 tons (22.1 % reduction vs. static CEF models), cuts operational costs by 6.8 %, and lowers carbon trading costs by 5.1 % through synergized carbon pricing, flexible hydrogen utilization, and collaborative cost-sharing. Results highlight how macro-level carbon accounting, meso-level energy technology, and micro-level stakeholder incentives form a self-reinforcing low-carbon dispatch mechanism, demonstrating systemic innovation for carbon responsibility allocation and economic-environmental synergy.