A review of barriers towards underground hydrogen storage

Hydrogen is considered as a clean and renewable energy carrier that can potentially replace fossil fuels in many applications, such as transportation and power generation. However, the widespread deployment of hydrogen technologies is hindered by the difficulty in storing and transporting this highly flammable gas. One potential solution to this problem is underground hydrogen storage, which involves storing hydrogen in geological formations such as depleted gas fields, salt caverns, and aquifers. While underground hydrogen storage has several benefits, including large storage capacity and reduced land use, it also faces several barriers that need to be addressed. In this review, we will discuss some of the major barriers to underground hydrogen storage.

1. Technical Challenges: The first and foremost challenge is to ensure the safe and reliable storage of hydrogen underground. This requires the development of reliable and cost-effective storage technologies that can prevent leakage and ensure the integrity of the storage site. Additionally, hydrogen storage requires high-pressure tanks, which can be expensive and challenging to install in geological formations.
2. Regulatory Barriers: The regulatory framework for underground hydrogen storage is still in its early stages of development, which can create barriers to deployment. Regulations are required to ensure the safety of the storage site, and to address potential environmental impacts, such as the risk of groundwater contamination. Currently, there is a lack of consistency in regulatory requirements across different jurisdictions, which can create uncertainty for investors and project developers.
3. Economic Viability: Underground hydrogen storage can be an expensive technology to develop and deploy. The cost of drilling, developing and retrofitting storage sites, and installing infrastructure to transport hydrogen to and from the storage site can be high. Furthermore, the economic viability of underground hydrogen storage is dependent on the availability of low-cost hydrogen production, which is still limited in many regions.
4. Public Acceptance: The public's perception of hydrogen storage and the associated risks is critical to the deployment of underground hydrogen storage. Public acceptance can be influenced by several factors, including the perceived risks associated with hydrogen storage and transport, the visual impact of storage infrastructure, and concerns over potential environmental impacts.
5. Technical Knowledge and Expertise: Finally, the development and deployment of underground hydrogen storage require significant technical expertise and knowledge. The lack of skilled workers and specialized equipment can be a significant barrier to the deployment of underground hydrogen storage.

In conclusion, underground hydrogen storage has the potential to play a crucial role in the decarbonization of energy systems. However, the deployment of this technology is hindered by several barriers, including technical challenges, regulatory barriers, economic viability, public acceptance, and the lack of technical knowledge and expertise. Addressing these barriers will require a coordinated effort from policymakers, regulators, investors, and industry stakeholders.