Optimal dispatch of integrated energy systems incorporating diversified energy storage under a long- and short-term synergistic strategy

Abstract

To enhance power adequacy in low-carbon power systems across a multi-timescale and improve the utilization of renewable energy, this work proposes a coordinated strategy for short-term power dispatch and long-term energy shifting in a hybrid integrated energy system (IES) supported by diversified energy storage. A time-period averaging method is employed to analyze the annual net power sequence, taking into account seasonal variations in renewable generation and load demand, thereby revealing supply–demand adequacy across different seasons. Based on the source–load matching characteristics, a long-term operational strategy for seasonal energy storage modules is explored to realize inter-seasonal energy shifting. Subsequently, a collaborative scheduling model for short- and long-term energy storage is developed, aiming to balance power regulation and energy adequacy, with a particular focus on the role of seasonal storage in alleviating seasonal power shortages and enhancing system economic and environmental performance. The results demonstrate that the coordinated operation of diversified energy storage systems significantly improves the energy efficiency, reduces energy losses, and lowers dependence on external energy supply in the hybrid IES. Under the proposed joint long–short-term storage strategy, the system independence reaches 85%. In terms of operational cost, energy costs and carbon emission costs are reduced by 8.56% and 11.35%, respectively, compared to short-term-only and long-term-only strategies. Although the inclusion of seasonal storage modules, such as electrolyzers and fuel cells, leads to a 4.31% increase in maintenance costs within a certain capacity range, it results in a 6.92% reduction in both energy and carbon emission costs. The proposed long–short-term coupled scheduling strategy for the hybrid IES effectively enhances system operational efficiency and adaptability.