Review on onshore and offshore large-scale seasonal hydrogen storage for electricity generation: Focusing on improving compression, storage, and roundtrip efficiency.

This article presents a comprehensive review of the current landscape and prospects of large-scale hydrogen storage technologies, with a focus on both onshore and offshore applications, and flexibility. Highlighting the evolving technological advancements, it explores storage and compression techniques, identifying potential research directions and avenues for innovation. Underwater hydrogen storage and hybrid metal hydride compressed gas tanks have been identified for offshore buffer storage, as well as exploration of using metal hydride slurries to transport hydrogen to/from offshore wind farms, coupled with low pressure, high flexibility electrolyser banks. Additionally, it explores the role of metal hydride hydrogen compressors and the integration of oxyfuel processes to enhance roundtrip efficiency. With insights into cost-effectiveness, environmental and technology considerations, and geographical factors, this review offers insights for policymakers, researchers, and industry stakeholders aiming to advance the deployment of large-scale hydrogen storage systems in the transition towards sustainable energy. [Display omitted] • Underwater H 2 buffer storage is proposed for deepwater floating wind installations. • Hybrid metal hydride – H 2 gas buffer stores are attractive for offshore locations. • Potential of thermal compression recognised for large-scale H 2 storage (LSHS). • Explore use of oxyfuel processes to improve roundtrip efficiency of LSHS. [ABSTRACT FROM AUTHOR]