A case study on the dynamic characteristics of a hydrogen and electricity co-production system driven by hybrid wind and photovoltaic power

Abstract Alkaline water electrolysis (AWE) is a technologically mature and economically viable method for hydrogen production, though its operational flexibility is limited by a narrow load range. Efficiently integrating renewable energy with AWE systems has become an important research focus. This study proposes a wind-photovoltaic-alkaline water electrolysis (W-PV-AWE) hydrogen production and power generation system, with nuclear energy incorporated as a backup power source to ensure continuous operation during periods of low wind and solar availability. An operational strategy based on power distribution and coordinated use of energy storage is introduced to avoid low-load conditions in the AWE system. A dynamic simulation model was developed and analyzed under typical daily renewable generation profiles. Key operational parameters-including current density, operating voltage, temperature, power consumption, and hydrogen production rate were systematically investigated throughout daytime operation. The results show that the AWE system maintains a minimum operating load above 30% at all times, achieves a specific energy consumption for hydrogen production as low as 4.17 kWh/Nm 3 , and reaches a peak energy storage capacity of 7.33 kW.