Assessment and outlook of large-scale underground hydrogen storage in Western Australia

Achieving deep decarbonization in Western Australia (WA) requires not only low-cost renewable hydrogen production but also high-capacity storage to buffer weather variability and shipping logistics. While underground hydrogen storage (UHS) is recognized globally, existing reviews lack a quantitative, region-specific framework integrating WA’s unique geology, infrastructure constraints, and export-oriented duty cycles. This study critically evaluates three UHS archetypes—depleted gas reservoirs (DGR), salt caverns (SC), and lined rock caverns (LRC)—by coupling international operational data with WA-specific techno-economic models. Unlike prior generic assessments, this work quantifies the levelized cost of hydrogen storage (LCOHS) adjusted for Australian labor and material markets, revealing that while DGR offers the lowest capital expenditure, LRC becomes cost-competitive at high cycling frequencies (>5 cycles/year) typical of export hubs. A novel, region-differentiated deployment strategy is proposed: (1) port-proximate LRC clusters for the South Coast to match high-frequency shipping cadences; (2) a two-tier system coupling near-port LRC with inland SC in the Canning Basin for the Pilbara; and (3) DGR as the primary baseload for the Mid-West, complemented by small-scale LRC for peak shaving. Furthermore, we identify critical gaps in materials compatibility, microbial geochemistry, and regulatory standards specific to WA’s sedimentary basins. By synthesizing geological suitability with economic viability, this review provides an actionable roadmap for selecting optimal storage technologies across WA’s diverse hydrogen hubs, transitioning UHS from a theoretical option to a bankable component of the export supply chain.