Coordinated Planning of Hybrid Energy Storage and Transmission Infrastructure for High Renewable Energy Penetration

Against the backdrop of increasing renewable energy penetration, distribution networks face the dual challenges of spatiotemporal mismatch between sources and loads, as well as the surging costs of physical capacity expansion. To address these issues, this paper proposes a joint planning method for distribution network expansion and hybrid energy storage (electrical, thermal, and cooling) in green power parks, aimed at enhancing renewable energy accommodation. With the objective of minimizing the total life-cycle cost, a comprehensive optimization model integrating network topology upgrades and hybrid storage capacity configuration is established, which is then formulated and solved as a Mixed-Integer Linear Programming (MILP) problem. The effectiveness of the proposed strategy is validated through simulation comparisons with traditional solely line-based expansion schemes on the standard IEEE 33-bus system. The results indicate that substituting network expansion with energy storage can significantly alleviate the hardware investment burden on the grid. Moreover, leveraging the spatiotemporal “buffer” effect of multi-energy hybrid storage and the operation mechanism of cooling-heating-power substitution, surplus photovoltaic generation is efficiently absorbed locally, maintaining a renewable energy accommodation rate consistently above 50%. Economic evaluation further confirms that this joint planning framework reduces the total life-cycle cost by 21.2% compared to conventional transmission expansion approaches. It significantly enhances the system’s flexible bidirectional regulation capabilities, providing a solid theoretical foundation for the coordinated development of networks and storage in green power parks with high renewable energy penetration.