IN Brief:
- Jacobs will support MESH planning, consenting, environmental, grid-connection, and regulatory work.
- EnergyPathways describes the development as a 300MW, 55GWh, 100-hour-plus long-duration storage project.
- The immediate programme includes Ofgem cap-and-floor work and a parallel Development Consent Order process.
EnergyPathways has appointed Jacobs as engineering and regulatory partner for the proposed MESH long-duration energy storage project, adding dedicated planning, consenting, environmental, and grid-connection work to the 300MW development.
Jacobs will support EnergyPathways’ submission to Ofgem’s forthcoming long-duration electricity storage cap-and-floor round and lead work required for the parallel Development Consent Order process. Its scope also includes stakeholder engagement, regulatory planning, and environmental services for the project in the Irish Sea and at Barrow-in-Furness.
EnergyPathways describes MESH as a 300MW, approximately 55GWh storage system with more than 100 hours of duration. The company is developing it around compressed-air energy storage using purpose-built offshore salt caverns, with surplus electricity used to compress air for later discharge through generation equipment.
The Jacobs appointment is not a final investment decision or construction award. Its importance lies in moving the project further into the approvals sequence that will determine whether the engineering concept can secure consent, a grid connection, and a revenue framework capable of supporting finance.
Jacobs is expected to develop a stakeholder engagement plan covering local councils and regional government, support the grid-connection application, and lead workstreams needed for both the Ofgem process and the DCO submission. The company will also contribute to statutory engagement and assessments covering socio-economic effects, regional employment, and supply-chain impacts.
Those tasks sit at the point where storage technology becomes infrastructure delivery. MESH requires suitable geological formations, large compression and generation machinery, high-voltage electrical equipment, grid access in both charging and generating modes, and consenting for offshore and onshore works that cross several regulatory interfaces.
The revenue model is equally important. Ofgem’s cap-and-floor mechanism is intended to give approved long-duration storage projects a minimum revenue level while limiting returns above an agreed ceiling, reducing exposure to merchant-market volatility and making capital-intensive assets easier to finance.
EnergyPathways says successful eligibility would underpin the project’s final investment decision and support debt and equity financing. Jacobs’ regulatory scope therefore sits directly between engineering development and bankability rather than functioning as an administrative exercise detached from project delivery.
The project has already moved through front-end engineering and financing activity. Earlier company updates set out a design of around 300MW and 55GWh, using four large offshore salt caverns, with operation targeted for the end of 2031 subject to approvals. The latest appointment concentrates on converting that concept into the evidence required for planning, grid, and revenue decisions.
Long-duration storage addresses a different system problem from conventional four-hour batteries. Shorter-duration assets can shift electricity across daily peaks and provide fast-response services, while a 100-hour-plus system is intended to carry surplus energy across several days of changing weather and demand.
Compressed-air storage also brings different operating characteristics. Large rotating machinery can contribute synchronous inertia and reserve capability alongside energy shifting, while geological storage separates energy capacity from the electrochemical cell volumes used in batteries. Actual system value will still depend on efficiency, plant availability, operating flexibility, and the costs of the compression, storage, and generation cycle.
Unlike a short-duration battery, the energy reservoir is not the expensive electrochemical component, but that does not make the plant simple. Compressors, turbines, heat-management equipment, cavern integrity, valves, piping, and electrical auxiliaries all have to operate through long charge and discharge cycles without undermining availability.
The grid connection remains a substantial engineering package in its own right. Charging creates a large controllable demand, while discharge turns the same asset into a 300MW generator, requiring protection, metering, system studies, control coordination, and connection arrangements that function in both directions.
Planning is similarly broad. Offshore caverns, marine and onshore interfaces, generation equipment, electrical connections, construction logistics, and environmental effects can fall under different approval regimes. Running the DCO, grid, environmental, and Ofgem workstreams in parallel is intended to reduce the risk of one unresolved issue holding back the rest of the project.
EnergyPathways says the next key milestone after its Ofgem submission will be formal confirmation of MESH’s eligibility for the cap-and-floor scheme. That makes Jacobs’ immediate task measurable: produce the planning, environmental, grid, and regulatory evidence needed to move a large storage concept closer to a financeable infrastructure decision.
If MESH reaches that point, attention will shift towards procurement, detailed engineering, construction, and commissioning. For now, the appointment marks the less visible stage on which those later milestones depend — proving that the project can be consented, connected, and supported by a revenue structure before anyone starts celebrating 55GWh of storage on a slide deck.
