Assessment of feasible strategies for seasonal underground hydrogen storage in a saline aquifer

• Published in: International journal of hydrogen energy Vol. 42; no. 26; pp. 16657 - 16666
• Main Authors: Sainz-Garcia, A., Abarca, E., Rubi, V., Grandia, F.
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 29.06.2017
• Subjects: Geological energy storage; Power-to-gas; Renewable hydrogen; Saline aquifer; Underground hydrogen storage; Renewable hydrogen; Saline aquifer; Underground hydrogen storage; Power-to-gas; Geological energy storage
• ISSN: 0360-3199; 1879-3487
• DOI: 10.1016/j.ijhydene.2017.05.076

Renewable energies fluctuate, resulting in temporary mismatches between demand and supply. The conversion of surplus energy to hydrogen and its storage in geological formations is one option to counteract this energy imbalance. This study evaluates the feasibility of seasonal storage of hydrogen produced from wind power in Castilla-León region (northern Spain). A 3D multiphase numerical model is used to test different extraction well configurations during three annual injection-production cycles in a saline aquifer. Results demonstrate that underground hydrogen storage in saline aquifers can be operated with reasonable recovery ratios. A maximum hydrogen recovery ratio of 78%, which represents a global energy efficiency of 30%, has been estimated. Hydrogen upconing emerges as the major risk on saline aquifer storage without using other cushion gases. However, shallow extraction wells can minimize its effects. Steeply dipping geological structures are key for an efficient hydrogen storage. [Display omitted] •Hydrogen storage in a saline aquifer is simulated by a 3D multiphase flow model.•Upconing emerges as the major risk on saline aquifer storage without cushion gas.•Steeply dipping structures are key for efficient hydrogen storage.•Seasonal hydrogen storage can be operated with reasonable recovery ratios.