Multi-criteria framework for ranking geological sites in underground hydrogen storage

Abstract

Underground hydrogen storage (UHS) is central to enabling a sustainable energy transition, providing a means to balance renewable intermittency through large-scale, long-duration storage. The success of such systems depends critically on site selection, which must integrate technical, economic, and environmental considerations. Here we apply seven multi-criteria decision-making methods to evaluate five storage options, salt caverns, lined rock caverns (LRCs), depleted oil reservoirs, depleted gas reservoirs, and saline aquifers, using 34 parameters. Across all methods, salt caverns emerge as the most suitable sites, followed by LRCs, while porous reservoirs and saline aquifers rank consistently lower. Analysis of parameter influence shows that 16 factors contribute positively to site suitability and 18 exert negative effects, underscoring the complexity of decision frameworks. This comparative assessment provides a transparent basis for risk evaluation and cost optimization, offering practical guidance for research, policy, and deployment of UHS.