Overview of DC Distribution System in Low-Carbon Building–Part I: Configuration, Architectures and Applications

The building sector consumes approximately 32% of global energy and generates 34% of carbon dioxide emissions. Consequently, advancing energy conservation and emission reduction within this sector plays a critical role in mitigating the global climate crisis. Integrating photovoltaic (PV) generation, combined electrical and thermal energy storage systems, direct current (DC) distribution, and flexible load management technologies within buildings, synergistically optimized across the power source, energy conversion, and demand sides, creates pathways for decarbonizing the building sector. This review begins by elucidating the system's key configuration: building PV, energy storage systems (ESS), DC distribution systems and flexible loads, elaborating on their specific configurations and applications within the building environment. Subsequently, the paper reviews and analyzes low-voltage direct current (LVDC) voltage levels from the perspectives of existing standards and DC load demands. Focusing on DC distribution network topologies, this paper introduces unipolar and bipolar DC systems along with relevant studies, and reviews typical network configurations applicable to single buildings and building clusters. Following this, twelve global application case studies are presented and discussed, along with their key operational parameters. Finally, this paper discusses directions for technical standardization and future development trends.