Subsea caverns in the pipeline for H2 storage

UK Oil & Gas Plc (UKOG) is planning to build a hydrogen storage facility at Portland Harbour in the UK county of Dorset, creating man-made salt caverns.

The port was used during the reign of Henry VIII before expanding to become one of the Royal Navy’s largest bases. It was being shut down in 1995.

The caverns, which energy firm ENGIE says can be as much as three times the size of the Arc de Triomphe in Paris, are created by drilling into geological salt deposits that are already there, and in Dorset these are plentiful.

Water is then injected into the salt to dissolve it, and the resulting brine is extracted, leaving a cavern where hydrogen can be stored under pressure.

The project has been several years in planning, with Dorset County Council granting Portland Gas Storage Ltd planning consent in 2008 – but it was never realised.

Now, after various twists and turns, the project has received a letter of support (LOS) from gas distribution operator SGN, which is planning an H2 Connect link from the storage site ultimately to a new UK-wide hydrogen grid.

“This project has the potential to store 3TWh of hydrogen in subsurface constructed salt caverns and is essential to decarbonising the Solent Cluster and Southern England,” said SGN regional development manager Graham Cox. “This hydrogen storage will provide inter-seasonal capacity, security of supply and pipeline stability for our proposed development of hydrogen pipelines in the region.

“It will enable the end use of hydrogen across industry, heating and transport, help meet growing regional energy demand, and support the transition to net zero emissions.”

At the time of writing, UKOG had not responded to Maritime Journal’s requests for details of the engineering scope of the project.

“Whilst UKOG’s proposed Project is at an early engineering design stage and there can be no certainty it will receive government Revenue Support, the company is committed to furthering this and its other essential strategic UK hydrogen storage projects which will remain as the focus of the company’s overall future strategy,” says UKOG. “The company expects to receive further LOS in due course,” a statement said.