Hydrogen salt cavern storage (H2SaltCavern)
Joint industry project
Challenge
Storing hydrogen in salt caverns can play an important role in helping deliver the energy transition while meeting the targets of the Paris Agreement. Hydrogen storage at scale will be used for various purposes such as energy security, decarbonizing industrial processes, balancing supply and demand, and maximizing recovery of variable electricity from wind and solar. There are four commercial hydrogen salt caverns and several pilot projects in operation globally. As the energy transition accelerates, the number of caverns storing hydrogen is expected to increase significantly. The underlying question is whether existing standards for natural gas salt cavern storage can be applied to hydrogen and, if not, how they need to be changed.
The storage of hydrogen in salt caverns requires good design, based around safety. DNV has contacted nearly 50 companies and gathered extensive feedback on the top industry challenges. Following studies by the Dutch Minister of Economic Affairs (KEM-28) and German Federal Ministry Economic Affairs (DVGW Roadmap for Standardization of Hydrogen) on development areas, DNV has identified the risk of fire & explosion as a knowledge gap, and proposes to develop guidelines to support industry in how demonstrating acceptable levels of safety should be approached around:
- Subsurface failure consequences
- Surface failure consequences
- Pipeline connection failure consequences
- Risk mitigation methods
Objective
DNV would bring together stakeholders on a 1.5 to 2 year JIP to develop a European focused and rationalized safety approach for development and operation of salt caverns for storage of hydrogen. The JIP would review the applicability of existing natural gas storage guidance for hydrogen with a focus on fire and explosion failure consequences and risk mitigation methods, e.g. surface effects of a blowout, fire plume behavior, explosion behavior, exclusion zones, separation distances and so on.
Approach
The scope would consist of phase 1 and phase 1 extension. Phase 1 (base case) would focus on data gathering, assessment of state-of-the-art practices, scenario development, threat assessment, identification of uncertainties and a gap analysis of standards and practices. This would be followed by consequence impact assessment, development of risk mitigation methods, mitigation consequence impact assessment, suggestions for extra requirements for hydrogen storage to cover the gaps and development of a guideline. The extension of phase 1 (subject to additional funding) would either address analysis and potential testing or address entirely different topics based on project member needs.
Project details
The project would aim to kick-off in April 2025, subject to funding and partners. The project outcomes will be to enhance confidence in hydrogen salt caverns, fire and explosion understanding and safety demonstration, facilitate certification and give participants the opportunity to influence best practice. Companies are requested to express intent to participate (subject to scope and contract) for receipt of a formal proposal.