Capacity optimization and energy dispatch strategy of hybrid energy storage system based on proton exchange membrane electrolyzer cell

The introduction of proton exchange membrane electrolyzer cells into microgrids allows renewable energy to be stored in a more stable form of hydrogen energy, which can reduce the redundancy of battery energy storage system and the abandonment of wind and photovoltaic energy. However, most studies of energy dispatch strategies for microgrids only focus on the costs without considering the long-life operation. Therefore, in this study, the proposed capacity optimization method first ensures that the optimized distributed energy capacity can meet the user demand even in the most impoverished meteorological conditions. Moreover, the optimal efficiency and operating conditions of the electrolyzer corresponding to the reference power are determined through the artificial neural network, thereby realizing efficient hydrogen production. Subsequently, the multi -objective energy dispatch strategy is analyzed and designed, considering both low-cost and long-life operations. Compared with the economical energy dispatching strategy, the multi-objective energy dispatching strategy only increases the average daily dispatching cost by 0.055 $, however, reduces the volatility indicator of the elec-trolyzer by 49 %, which is beneficial to the sustainable operation of the electrolyzer. Furthermore, the required electrolyzer capacity is also reduced by 17.5 % by suppressing the power fluctuation of the electrolyzer. This study can provide useful information for understanding the energy dispatch strategy in hydrogen-electric coupling microgrids.

Automated summary

This study introduces proton exchange membrane electrolyzer cells into microgrids for storing renewable energy in a more stable form of hydrogen energy. It proposes a capacity optimization method to ensure that the distributed energy capacity meets user demands, even under impoverished meteorological conditions. An artificial neural network is used to determine the optimal efficiency and operating conditions of the electrolyzer for efficient hydrogen production. A multi-objective energy dispatch strategy is designed considering both low-cost and long-life operations. The study shows that this strategy reduces the volatility and required capacity of the electrolyzer while increasing the average daily dispatching cost by a small amount.