Optimal Planning of Gird-connected Regional Microgrid for Energy-intensive Areas Considering Interface Flow Contracts

The imperative installation of distributed energy resources to mitigate greenhouse gas emissions in the power sector has introduced operational challenges. In response, microgrids are emerging as a solution, signifying a transition from conventional centralized systems to regional self-sufficient decentralized energy systems. Within the context, this study proposes four contract types governing interface flows between main grid and microgrids to enhance system benefits through proactive operational integration with the primary system. Additionally, the study presents a methodological framework for optimal planning and cost estimation, incorporating mathematical optimization theory and the unique characteristics of each contract type. A case study, utilizing diverse datasets such as authentic load profiles, meteorological observations, and technical and cost parameters, reveals that optimal investments vary based on contract types on interface flows. Notably, it highlights that effectively managing volatility in the lower-level system, necessitates increased investments in flexibility resources. Furthermore, an analysis of facility investment changes based on the target energy self-sufficiency rate indicates a gradual increase in the allocation of flexibility resources as the self-sufficiency rate increases.