Sustainable DCs from an integrated energy systems perspective: System characteristics, operational mechanisms and coordinated frameworks

DCs are evolving from electricity-intensive computing facilities into flexible nodes within integrated energy systems, driven by the rapid growth of cloud services, artificial intelligence workloads, and decarbonization requirements. This review examines DCs from an integrated energy systems perspective, focusing on the coupled interactions among electricity consumption, computational workloads, and heat generation. The energy characteristics of key DC subsystems are analyzed to identify fundamental electrical thermal computational coupling mechanisms and sources of operational flexibility. Representative coordination frameworks are reviewed and classified according to economic, low-carbon, and resilience-oriented objectives, highlighting how workload elasticity, thermal inertia, energy storage, and communication infrastructure have been leveraged for coordinated operation. In addition, critical technical challenges limiting large-scale deployment are synthesized, including electricity-centric infrastructure planning, fragmented modeling and forecasting of energy data interactions, insufficient exploration of cross-sector energy reuse, and evaluation frameworks that fail to capture dynamic flexibility and system-level value. Based on these insights, future research directions are outlined to support coordinated electricity and heat computation operation and the development of sustainable and resilient DC infrastructures.