The development of the international shipping industry, along with the rise of unmanned ships and their charging needs, has increased the number of docked vessels. Environmental pollution is exacerbated by the diesel generators on these ships, making shore power a crucial solution for developing green ports. Currently, a lack of unified technical principles exists to guide the development of shore power due to the different practical situations of each port. The overall principles and technical principles model for shore power system planning, along with a comparative analysis of planning technical principles and load forecasting, are discussed and illustrated in this paper. A hierarchical technical principles model is proposed to guide the design and optimization of the shore power system. Based on these principles, technical guidance and operational norms for the application of shore power to ships can be provided.