Integrated energy storage and transmission solutions: Evaluating hydrogen, ammonia, and compressed air for offshore wind power delivery

This paper introduces a novel dual-purpose transmission system that integrates power transmission and energy storage using hydrogen, ammonia, and compressed air—an area largely unexplored in the literature. Unlike conventional cable transmission, which requires separate storage infrastructure, the proposed approach leverages the transmission medium itself as an energy storage solution, enhancing system efficiency and reducing costs. By incorporating a defined storage allocation factor, this study examines the delivery of offshore-generated power to onshore locations, calculating the necessary media flow rates and evaluating the required transportation infrastructure, including tunnels and pipelines. A comparative cost-effectiveness analysis is conducted to determine optimal conditions under which storage-integrated transmission outperforms conventional cable transmission. Various transmission powers, storage fractions, pressures, and distances are analysed to assess feasibility and economic viability. The findings indicate that for a 75 % storage allocation factor, compressed air can transmit up to 450 MW over 300 km more cost-effectively than cables, while hydrogen enables 230 MW transmission beyond 310 km. Ammonia proves to be the most efficient, facilitating the transmission of over 2000 MW across distances exceeding 140 km at a lower cost than cables, all without requiring onshore storage. Moreover, for a 500-km transmission line, compressed air, hydrogen, and ammonia can store the equivalent of 62, 58, and 152 h of wind farm output, respectively, significantly reducing the need for additional onshore storage. This study fills a critical research gap by optimizing offshore wind power delivery through an innovative, cost-effective, and scalable transmission and storage approach. • Proposes a novel dual-purpose pipeline system for simultaneous power transmission and energy storage. • Explores hydrogen, ammonia, and compressed air as alternative power transmission media, filling a research gap. • Identifies optimal cost-effective conditions for offshore wind power transmission and storage integration. • Demonstrates ammonia's feasibility for transmitting 2000 MW over 140 km more economically than cables. • Shows compressed air can store 62 h of wind power, enabling up to 450 MW transmission over 300 km.