[Objective] To accelerate the realization of the “dual carbon” goals and improve both the economic viability and hydrogen supply stability of green hydrogen systems

this study designs an off-grid hydrogen production system utilizing a multi-type electrolyzer cluster. [Methods] First

the start-stop operational characteristics of the multi-type electrolyzer cluster were modeled. Considering the constraints of stable hydrogen supply for downstream chemical production

a capacity configuration optimization model for the off-grid green hydrogen system was established with the objective of maximizing net revenue. Second

the uncertainty of wind and solar power output was analyzed. The k-means clustering algorithm was utilized to obtain multiple joint windsolar output scenarios. Latin hypercube sampling(LHS) was employed to describe the intraday randomness of wind and solar output

while a Markov Chain(MC) was adopted to simulate the inter-day correlation

thereby generating the required long-term stochastic scenarios. Finally

a case study was conducted based on a specific green hydrogen project in Xinjiang for simulation analysis. [Results] The proposed long-term stochastic scenario generation method can effectively simulate the uncertainty and correlation of continuous wind and solar power output. Compared with single-type electrolyzer configuration schemes

the multi-type electrolyzer scheme can significantly improve system economics. [Conclusion] The combination of a multi-type electrolyzer cluster and the long-term stochastic scenario generation method enhances the economic performance and operational reliability of off-grid green hydrogen systems

providing a reference for the planning of high-proportion renewable energy hydrogen production systems.