Evaluation of the short- and long-duration energy storage requirements in solar-wind hybrid systems

Renewable energy generation systems typically exhibit variable output. The integration of short- and long-duration energy storage systems is the strategy to reconcile the discrepancy between renewable energy generation and load demand. This investigation aims to evaluate the feasibility of utilizing combinations of short- and long-duration energy storage under diverse conditions. The study involves energy generation systems incorporating photovoltaic arrays, wind turbines, batteries, hydrogen storage, thermal energy storage, and concentrated solar power components. The analysis covers 12 distinct regions within China, each paired with two distinctive demand profiles. The optimal capacity for each system's components was determined to minimize the levelized cost of energy (LCOE) while maintaining a loss of power supply probability (LPSP) of 1 %. Subsequently, the energy waste and environmental performance of the optimized system were examined. Additionally, the impact of maximum component capacity limitations on the optimal system configuration was investigated. Results indicate that systems equipped with both batteries and thermal energy storage outperform those paired with batteries and hydrogen storage in terms of economic performance under the LPSP of 1 % constraint. Moreover, the inclusion of a concentrated solar field proves to be economical in regions with ample solar resources. When calibrated to capacities that yield minimal LCOE while ensuring exceptional power supply reliability, the benefits of reducing energy waste with a battery and hydrogen storage configuration become pronounced. For installations where the capacity of generation components does not exceed 600 MW, a system integrating battery and hydrogen storage demonstrates superior economic performance in regions with abundant wind resources.