Techno-economic analysis of large-scale hydrogen storage in salt caverns for renewable energy integration and energy market optimisation

This study presents a techno-economic analysis of large-scale hydrogen storage using salt caverns in Ireland to mitigate wind energy curtailment and optimise energy market integration. The research explores the feasibility of converting surplus wind energy into hydrogen during off-peak periods and utilising it— in the electricity day-ahead market (DAM) and other sectors such as transportation and heating — when demanded. A modelling framework incorporating geological, operational, and economic constraints was developed to assess hydrogen storage costs and overall system’s profitability for the presented case. The findings indicate that while seasonal hydrogen storage for the supply in electricity market alone is economically challenging (37.6€/kg hydrogen), integrating hydrogen into multiple energy sectors significantly enhances viability (2-3€/kg hydrogen). Sensitivity analysis highlights the critical impact of electrolyser capital costs and operational expenses on economic feasibility. The study concludes that a multi-sectoral hydrogen strategy can improve renewable energy utilization, support grid stability, and advance decarbonization objectives.