An integrated energy storage system based on hydrogen storage: Process configuration and case studies with wind power

The interconnection between a renewable power generation facility and a power grid poses challenges because of volatility and intermittent characteristics. Energy storage is one of the best solutions for this problem. This paper presents an integrated energy storage system (ESS) based on hydrogen storage, and hydrogen-oxygen combined cycle, wherein energy efficiency in the range of 49%-55% can be achieved. The proposed integrated ESS and other means of energy storage are compared. The results show that the proposed integrated system cannot be constrained by geological conditions and availability of materials, and appears to be an appropriate tool for the development of renewable power. Moreover, a case study is conducted for a special wind power plant with a nominal power of 100 MW and that generates electricity of 225 GWh/y. The integrated system is designed based on the daily wind load. Energy efficiency and preliminary economic comparison studies for the integrated system operated in two modes show that up to 50% average net efficiency of the integrated ESS can be achieved and that the integrated ESS can stabilize the intermittent wind power. Therefore, the integrated ESS can be useful to mitigate the bottleneck of renewable power development.