As energy systems transition toward low-carbon alternatives, hydrogen storage has become critical infrastructure for supporting clean energy production and distribution. While aboveground storage tanks remain costly and constrained by safety and capacity limits, underground storage in depleted hydrocarbon reservoirs offers a scalable solution that repurposes existing oil and gas infrastructure.
Qatar's North Field—one of the world's largest natural gas reserves—presents an opportunity to develop underground hydrogen storage (UHS) systems to support future blue ammonia production facilities. Researchers used QASR simulation software to assess the technical feasibility of injecting and storing hydrogen in a partially depleted reservoir at the North Field.
The study examined three injection scenarios: operation without cushion gas, and operations using either nitrogen or carbon dioxide as buffer gas injected before hydrogen. Cushion gas serves a critical function by maintaining reservoir pressure and stabilizing flow conditions during hydrogen injection and withdrawal cycles.
Results demonstrated that storing hydrogen without cushion gas yielded the lowest recovery factor at 69.6%, meaning nearly 30% of injected hydrogen would remain trapped in the reservoir. By contrast, both nitrogen and carbon dioxide cushion gas scenarios achieved recovery factors exceeding 75%, significantly improving the economics of the storage system.
This work differs from most prior research by focusing on partially depleted reservoirs rather than fully depleted fields, and by providing insights specific to Qatar's geological and operational conditions. The findings underscore the importance of optimizing cushion gas selection and composition for maximizing hydrogen recovery efficiency.
For power and energy professionals, these results validate the technical feasibility of large-scale hydrogen storage in existing hydrocarbon reservoirs, removing a key barrier to integrating hydrogen into regional energy systems. As countries develop hydrogen economies, deploying UHS infrastructure in existing gas fields could accelerate the transition to lower-carbon energy carriers while utilizing proven geological containment.
