EirGrid is pioneering the use of deep‑micro‑tunnelling to install high‑voltage electricity cables across central Dublin as part of its Powering Up Dublin project. Surveys showed that conventional trenching was not feasible on the congested urban route between the Inchicore and Poolbeg substations due to dense underground utilities.

The planned micro‑tunnel will run 10.5 km with a three‑metre diameter, at depths between 15 and 60 metres. It will carry two 220 kV circuits, upgradeable to 400 kV, reducing the cable route for both circuits from 30 km to just 10.5 km. The approach minimises disruption to surface traffic and daily urban life while avoiding conflicts with existing infrastructure.

Strategic planning is prioritising minimal public impact. The tunnel is set to pass beneath the Grand Canal and other green spaces, while access shafts will be sited to limit disturbance. Routes for the Finglas to Poolbeg and Carrickmines to Poolbeg sections have been finalised and are progressing through regulatory approvals, with construction expected to begin in 2026. Offshore cable sections are pending maritime and planning consents.

The micro‑tunnelling solution represents both technical innovation and operational efficiency. It allows a more direct cable alignment, reduces environmental and social disruption, and sets a precedent for urban power upgrades in Ireland. The project addresses the urgent need to modernise Dublin’s ageing electricity infrastructure, expand capacity for a growing population, and accommodate increasing electricity demand driven by economic growth and electrification initiatives.

EirGrid continues to consult stakeholders and refine the final route for the Inchicore to Poolbeg tunnel, with updates expected in 2026.

Discover the full article of Dublin’s grid transformation and the innovative tunnelling technology in action.