Operation strategy optimization of an integrated proton exchange membrane water electrolyzer and batch reverse osmosis desalination system powered by offgrid wind energy

Abstract

Operation strategy of the integrated wind-hydrogen system is the key to ameliorate the negative impacts of the fluctuated wind power on the hydrogen production capacity and durability of electrolyzer. However, the desalination system supplying pure water to electrolyzers was neglected previously, with which the practical operation strategy of the hybrid wind-hydrogen-desalination system has yet to be investigated. In this work, we proposed a novel control strategy named step-by-step start for wind-hydrogen-desalination system consisting of wind turbine, proton exchange membrane water electrolyzer (PEMWE), battery and batch reverse osmosis (BRO) desalination system, which can produce hydrogen and fresh water. Real-time wind data from Shenzhen, China were used as input to the integrated system. The results demonstrate the wind-hydrogen-desalination system with the proposed strategy can improve the hydrogen production by 17.55 %, the energy efficiency by 17.68 % in August, and increase hydrogen production by 10.29 %, the energy utilization efficiency by 10.44 % in December compared with traditional strategies. At low wind speeds, the switching times of PEMWE for this strategy is higher than the other strategies, while at high wind speeds, the switching times of PEMWE is significantly decreased. This work provides insights into the practical operation strategy for wind-hydrogen-desalination system depending on the real-time wind speed.

Keywords

• Wind-hydrogen-desalination system
• Step-by-step start
• Hydrogen production
• Fresh water
• Switching times