Abandoned mines could become energy storage for a fossil-free industry

As the industry transitions to fossil-free production, the need for efficient energy storage is increasing. A new research project at Luleå University of Technology will investigate the potential for using abandoned mines for large-scale underground hydrogen storage (UHS).

The project, called SUV, is being conducted in collaboration with LKAB and Vattenfall and aims to contribute to the green transition and the achievement of carbon neutrality in the steel industry in Norrbotten. The project is funded by the Swedish Agency for Economic and Regional Growth through the Just Transition Fund.

“Developing safe and efficient underground hydrogen storage is crucial for the industry’s transition to fossil-free production. By using former mining areas, we can both reduce environmental impact and create a sustainable energy infrastructure. The SUV project is an important step towards realising this vision,” says Ping Zhang, Professor of Mining and Geotechnical Engineering at Luleå University of Technology.

There are a large number of abandoned mines in Sweden, many of them located in mountainous regions that were once a key part of the country’s mining industry. These abandoned mines could now play an important role in the transition to a fossil-free future by becoming potential sites for hydrogen storage.

The European Union aims to phase out fossil fuels by 2050, which means the mining, energy, and steel industries must develop new technologies to meet future demands. An important aspect of this transition is the storage of hydrogen, which can be used to produce fossil-free steel. The SUV project focuses on developing technical guidelines for the use of lined rock caverns (LRC) for safe and effective hydrogen storage in former mining areas.

Technical, economic, and legal challenges

The project involves a comprehensive investigation of the technical, economic, legal, and regulatory aspects related to underground hydrogen storage. One of the major challenges is adapting LRC technology, which is currently used for natural gas storage, to the specific properties of hydrogen. Among other issues, the project will address problems such as permeability of the liner, cyclic loading, and temperature fluctuations.

“To succeed with large-scale hydrogen storage, a combination of expertise in rock mechanics, materials science, and energy systems is required. We must understand how hydrogen affects the bedrock and the materials used in the storage construction,” says Ping Zhang.

In addition to the technical aspects, there are economic and legal hurdles to overcome. The scalability and profitability of the storage method must be evaluated, as well as how regulations and permits for underground storage can be adapted to facilitate large-scale implementation.

Promoting research and industrial competitiveness

The SUV project is expected to provide important research results that could strengthen Swedish industry in its transition to climate neutrality. The results will support the development of hydrogen-based energy systems and create new business opportunities for the mining, energy, and steel industries. The research will also contribute to education and skills development at Luleå University of Technology by producing new knowledge on energy storage, rock engineering, material science, and the economic and legal aspects of resource management in former mining areas.

“By repurposing former mining areas, we can create a sustainable energy infrastructure while strengthening Sweden’s position in hydrogen technology. This is an initiative that could bring long-term benefits for both industry and society,” says Ping Zhang.