Dual-level collaborative optimization model of integrated energy systems with electricity-thermal-hydrogen hybrid energy storage

Integrated energy systems (IES) that incorporate multiple energy storage technologies, such as electricity, thermal, and hydrogen storage, can significantly enhance system flexibility. However, challenges remain due to the high investment costs and low conversion efficiency associated with these storage technologies, which complicate the planning and operation of IES. Therefore, in this paper, a novel dual-level collaborative optimization model for an electricity-thermal-hydrogen IES (ETHIES) is proposed to address these challenges. In ETHIES, the electricity thermal hydrogen hybrid energy storage is considered to improve the flexibility and energy utilization efficiency, while this enables ETHIES to achieve coordinated multi-energy regulation across temporal scales and cascaded energy utilization. Then, a novel dual-level collaborative optimization model is developed to achieve dynamic coordination between planning and operation stages. The upper level determines the capacity configuration of the energy storage system to minimize annual total costs, and the lower level obtains the optimized system operation scheme by minimizing operational costs. This optimization model enables the proposed ETHIES to address short-term fluctuations while adapting to long-term energy structure transitions. Moreover, a hybrid solving method combining the whale optimization algorithm and CPLEX solver is used to solve the upper-level and lower-level problems, respectively. Finally, the simulation experiment results demonstrate that the proposed ETHIES can significantly reduce energy storage investment costs and dependence on natural gas. Besides, the proposed dual-level optimization model can improve the economy and efficiency of the ETHIES, providing valuable strategies for optimizing both energy storage configuration and operational dispatch.