Optimal Planning of Electric–Hydrogen Coupled Integrated Energy System: A Comprehensive Review

Against the backdrop of climate change, the volatility of energy supply and demand in integrated energy systems (IESs) has intensified, resulting in heightened scheduling challenges. Electric–hydrogen coupling has emerged as a pivotal approach to fostering multi-energy complementarity while enhancing the flexibility and stability of IES. Rational planning of an electric–hydrogen coupled integrated energy system (EH-IES) can further strengthen energy interconnection and mutual support. First, the architecture and diverse coupling modes of the EH-IES are outlined based on key technologies and coupling mechanisms. Accurate modeling serves as the “cornerstone” of planning, with electric power and hydrogen energy equipment acting as the foundational “carriers” and electric–hydrogen coupling devices as the critical “link.” By examining application scenarios across the transportation, building, and industrial sectors, the study analyzes EH-IES planning scenarios, objectives, and modeling methodologies. Sector-specific planning primarily focuses on equipment configuration and layout, evaluated from economic and/or environmental perspectives. Finally, future research directions for EH-IES planning are proposed, addressing multiple uncertainties, energy demand dynamics, and market mechanisms. These insights aim to provide a reference for subsequent studies.