Two-Stage Co-Optimization of a Park-Level Integrated Energy System Considering Grid Interaction

Park-level integrated energy system has the potential to improve system efficiency and facilitate friendly interaction with the power grid. This paper proposes an integrated energy system for parks that harnesses wind, solar, and geothermal energy sources, alongside three types of energy storage: cold, heat, and electricity. A two-stage coordinated optimization method is proposed that considers both long-term system operation and short-term operation scheduling. The effectiveness of this method is compared with an actual case in Tianjin, and the results demonstrate that the capacity configuration optimized by the two-stage optimization method yields economic and energy-saving benefits under long-term operation. It also satisfies the requirement of near-zero external power load fluctuation or participates in peak shaving and valley filling on the grid side during operation. The proposed two-stage optimization method achieves optimal capacity under long-term operation and favorable interaction with the power grid during daytime scheduling, thereby reducing decision-making difficulties.