Dynamic Operation and Optimization of Green Hydrogen Production Systems

This thesis investigates the dynamic operation and control of green hydrogen production systems based on water electrolysis, particularly under variable power input from renewable energy sources. The study begins with a comprehensive literature review of electrolysis technologies, with emphasis on proton exchange membrane (PEM) and alkaline electrolyzers, their integration with renewable energy, and the role of auxiliary components and balance of plant (BoP). A dynamic model of an alkaline electrolyzer system was developed and used to design and evaluate control strategies—specifically feedback, feedforward, and cascade control—to manage key process variables such as temperature and pressure during fluctuating operating conditions. Based on a representative case study, these strategies were compared to assess their effectiveness in ensuring stable operation. In the second phase, an optimization problem was formulated and solved to evaluate the trade-offs between the number of electrolyzer stacks, BoP sizing, capital expenditure (CAPEX), operational expenditure (OPEX), and overall system efficiency. This multi-disciplinary approach combined process modeling, control system design, and techno-economic analysis to support the development of scalable, cost-effective hydrogen production systems powered by renewable energy. The findings contribute to a better understanding of how control and design choices influence the performance and viability of electrolysis-based hydrogen technologies under dynamic real-world conditions.