Coordination Operation Strategy and Capacity Optimization of Off-grid Wind-solar Hybrid Hydrogen Production System

Hydrogen production from off-grid wind and solar power generation is an important route to reduce the fluctuating impact of wind and solar power generation on the power grid, which also promotes the consumption of renewable energy. While the unstable wind and solar resources also exert negative influence on the efficient and stable operation of the hydrogen production system. Therefore, this study develops an off-grid wind-solar hybrid hydrogen production system, which consists of wind/photovoltaic power generation, alkaline electrolytic (AE) cell and battery energy storage; a mode allocation method and a day-ahead planning of hydrogen strategy coupled with energy storage equipment are proposed. Considering the unit hydrogen production cost and the rate of abandoning wind/solar power, the improved non-dominated sorting genetic algorithm II (NSGA-II) is adopted to optimize the capacity configuration. The case analysis indicates that energy storage strategy improves system economy and hydrogen production efficiency. Compared with the single electrolyzer allocation strategy, the unit hydrogen production cost and the wind-solar energy abandon ratio are reduced by 11.9% and 55.6%, respectively. In addition, the operation strategy effectively exerts the advantages of battery regulation and buffering to suppress the frequent fluctuations of the electrolytic cell, and thus the number of start-stop times reduces by 44.3%. The research results will provide a reference for the development of efficient off-grid renewable hydrogen production. © 2024 Chin.Soc.for Elec.Eng.