Infrastructure solutions company Costain has been appointed by EnergyPathways PLC (EPP) to carry out a strategic site study for the onshore elements of the Marram Energy Storage Hub (MESH).

MESH, located approximately 15km off the coast of Blackpool, will play a key role in the UK government's clean energy strategy by providing long-duration energy storage using a combination of natural gas, hydrogen, and compressed air technologies. The hub is designed to enhance energy resilience while supporting the country’s transition to net-zero emissions.

Costain's front-end engineering and design team will compare potential locations for the onshore process facilities and related infrastructure. The study will examine factors such as connectivity to gas and electricity networks, construction costs and timelines, and reuse of existing infrastructure to determine the most effective site for development.


Once built, the onshore facilities will support:

• Natural gas storage and production

• Compressed air Long Duration Energy Storage (LDES)

• Hydrogen storage

• Clean hydrogen, ammonia, and graphite production

• Flexible clean power generation

Grant Johnson, Technical Director at Costain, said: "MESH is an ambitious, exciting project that will enhance the UK’s energy resilience, and enable more clean energy generation through large-scale energy storage.

"We know just how important it is to make robust choices at the early stages of a project, and we are looking forward to helping EPP with site selection, using our experience in delivering energy storage infrastructure to inform decision-making on aspects such as constructability and sustainability."

The Marram Energy Storage Hub will utilise the depleted Marram gas reservoir for natural gas storage. As the project progresses, it will incorporate Hybrid Compressed Air Energy Storage (H-CAES) technology to store surplus energy generated by offshore wind by compressing air into adjacent salt caverns. These caverns will also serve as a storage solution for green hydrogen, either produced through the H-CAES system or delivered via Project Union, a National Gas initiative repurposing the UK's gas transmission network to link hydrogen production, storage, and end users.