Underground Hydrogen Storage: A Critical Review in the Context of Climate Change Mitigation

Increasing population and anthropogenic activities are leading to a rise in global temperatures called global warming and climate change. To tackle this crisis, substantial efforts have been made such as renewable energy expansion and implementation of carbon capture and storage (CCS) projects. The Paris Agreement's goal is to limit the increase in global temperature and climate change mitigation strategies are adopted to achieve it. Decarbonization, negative emissions, and radiative forcing geoengineering are important technologies for this purpose because they decrease potential risks. Hydrogen has great potential in clean combustion and reduction of carbon emissions in different sectors like steel production. The cost trends indicate that green hydrogen could become a comparatively more efficient technology as compared to hydrogen generated from fossil fuels in the coming years. There is a need for hydrogen storage to support grid balancing and renewable energy systems. This study highlights the limitations and benefits of underground hydrogen storage mechanisms, including salt caverns, porous rock formations, and depleted hydrocarbon reservoirs. These are sustainable methods because they offer economic feasibility and large-scale storage, but it is important to consider geological suitability, hydrogen embrittlement, and environmental concerns. According to the literature, underground hydrogen storage is a better option than above-ground storage. The future outlook predicts that there will be increased investments in underground hydrogen storage technologies in the global transition to a greener energy paradigm.