EnergyPathways has formally accepted a gas storage development license for the East Irish Sea and has initiated the work program for its MESH offshore energy storage project.

The company plans to conduct site surveys in the third quarter of 2026 to gather environmental, geological, and seabed data. This information will support engineering, regulatory, and subsurface studies as the project progresses to its next development phase.

The licensed area has the capacity to accommodate up to 60 subsea salt caverns for large-scale energy storage. These caverns could support compressed air energy storage, the transition from natural gas to hydrogen storage, and hydrogen production, subject to regulatory approvals and financing.

EnergyPathways stated that the MESH project, formally named the Marram Energy Storage Hub, has been designated by the UK government as a nationally significant infrastructure project. It is targeted for operational start-up in 2031 and is expected to become the UK's largest integrated energy storage facility.

The company also welcomed the decision by the UK's Office of Gas and Electricity Markets to open a second application window for the Long Duration Electricity Storage cap and floor mechanism. EnergyPathways indicated it plans to submit the compressed air energy storage component of the MESH project for consideration under this scheme.