Collaborative Operation of Renewable Energy Hydrogen Production Systems Considering Balanced Utilization and Extended Lifespan of Multi-Electrolyzers

To address the challenges of low efficiency, poor economic performance, and limited adaptability in renewable energy-coupled alkaline water electrolysis (AWE) systems, this study proposes a power-state rolling optimization strategy (PSROS) based on a two-stage optimization framework. First, the large-scale AWE system is divided into multiple modules to reduce the variable dimension of the optimization problem. Then, a simplified module-level optimal efficiency model is developed based on the efficiency characteristics of AWE units. Subsequently, multi-objective optimization models are constructed at the module and unit levels, comprehensively considering hydrogen production volume, lifespan degradation, and utilization balancing. Finally, a finite-horizon rolling optimization mechanism is introduced to solve the two-stage optimization problem, improving the continuity and rationality of scheduling decisions at the end of each optimization horizon. Annual case study results demonstrate that, under the non-battery scenario, PSROS improves system efficiency by 9.92%, 11.12%, and 3.81%, and reduces the levelized cost of hydrogen (LCOH) by 4.14, 5.43, and 2.35 CNY/kg compared with the simple start-stop strategy (SSSS), array rotation strategy (ARS), and rolling optimization strategy (ROS), respectively. With battery integration, the system efficiency is further improved by 0.77%, and the LCOH is further reduced by 0.49 CNY/kg.