Hydrogen-electricity-heat sector Coupling: Review of integrated models, control strategies, challenges, and future research directions

The integration of hydrogen, electrical, and thermal energy systems represents a crucial direction for deep decarbonization by enhancing energy flexibility, maximizing the use of renewable resources, and facilitating inter-sectoral energy exchanges aligned with consistent climate and energy availability objectives. This review consolidates recent developments in the integrated modeling and control of hydrogen-electricity-heat (HEH) coupling, emphasizing optimization, real-time operational strategies, and data-driven methodologies that enhance resource efficiency and system robustness. Empirical data from simulations and pilot investigations indicate that synchronized HEH operations can reduce renewable energy cutting, increase overall system and decrease CO₂ emissions compared to uncoupled systems. We scrutinize deterministic, stochastic, dynamic, and hybrid physics-artificial intelligence (AI) frameworks, including novel AutoML-assisted methodologies, alongside hierarchical and predictive control strategies. Outstanding challenges in scalability, multi-time-scale coordination, uncertainty mitigation, interoperability, and market structuring are identified, and a strategic framework is proposed for hybrid physics-ML modeling, decentralized multi-agent control, and digital-twin-enabled optimization to encourage equitable, cost-effective, and climate-resilient HEH energy ecosystems across varied geographical and socio-economic contexts globally.