Morlais tidal energy scheme, North Wales

Published 8th December 2022

The major Morlais tidal project off Anglesey has received £31m of funding from the EU’s regional funding programme and will provide future developers with an offshore platform to harness tidal energy generation. The zone consists of a seabed area of 35 sq km to the west of Holy Island and will have a generating capacity of up to 240MW, making it one of the largest tidal stream-energy sites in the world.

This development will provide renewable energy to generate clean, zero carbon electricity, to power more than 180,000 homes once fully operational.

Our client, Stockton Drilling Ltd, was appointed by Mentor Mor to undertake the installation of five 600 metre-long, 450mm diameter horizontal directional drills (HDD) with associated HDPE ducts to provide the conduits for the future power export cables. Each HDD will have an onshore entry point and extend out to sea, passing below 30-metre-high costal cliffs and the intertidal zone to an exit point located offshore.

Our geotechnical team in Scotland designed the bores for the scheme undertaking a range of surveys and investigations for their implementation. The scenic site is exposed to the full force of the Irish Sea, constraining the potential to undertake offshore intrusive geotechnical investigations. To provide information on ground conditions along the length of the drills, a trial HDD pilot bore was completed and aerial supplemented topographical survey data was captured using a LiDAR-equipped drone. The team also carried out a series of seismic surveys, seeing our experts gather bathymetrical and sediment data.