SSEN Transmission has reached a key milestone in its Spittal to Peterhead subsea cable link project, with onshore and offshore enabling works now underway.
The 203km, 2GW High Voltage Direct Current (HVDC) link will connect the Banniskirk Hub substation development in Caithness to the Netherton Hub in Aberdeenshire, with 166km of cable running subsea from Sinclair’s Bay in Caithness through the Moray Firth to Rattray Head near Peterhead.
Once complete, the subsea link will provide a secure and efficient route for renewable energy to flow to demand centres across the country – supporting national clean power and energy security ambitions, while unlocking significant opportunities for local businesses and supply chains across the north of Scotland.
Global cable manufacturer NKT, which has been contracted to deliver the cable, has appointed Aberdeen‑based civil engineering specialists Nicol of Skene and Caithness‑based John Gunn & Sons to construct the onshore cable sections at Peterhead and Spittal, respectively.
One of the key onshore activities now underway is horizontal directional drilling (HDD) at the Rattray Estate north of Peterhead. This marks the first HDD operation for the project, with additional HDD activity planned at both onshore cable sections in the months ahead. The trenchless method will create bores beneath the U37B Rattray Road, allowing the 525kV HVDC cables to be installed safely while minimising disruption for road users and protecting the surrounding environment. Work on this initial HDD activity is expected to be completed by spring.
Meanwhile, offshore activity is progressing, with marine survey specialists Fugro commencing nearshore investigations to inform the final subsea cable route.
Fugro’s jack-up barge, WaveWalker1, set up for site investigation activities, is preparing to carry out geotechnical borehole investigations at Rattray Head to gather detailed information on seabed composition and nearshore geology, before it moves on to Sinclair’s Bay.
These operations have been planned to be as minimally invasive as possible. Borehole locations have been carefully selected – with support from geophysical data – to avoid unnecessary drilling.
This approach will help ensure the subsea route is designed and delivered safely and efficiently, with full consideration for the marine environment.
Niall MacLeod, Project Director for the Spittal to Peterhead project, said:
“The start of HDD works by NKT and their sub-contractor Nicol of Skene, and the mobilisation of Fugro’s WaveWalker1 jack-up barge contracted directly to SSEN Transmission for nearshore marine surveys, mark an exciting milestone for the Spittal to Peterhead project.
“These early activities lay the groundwork for a resilient, future-ready HVDC link that will help deliver the clean power and energy security the UK needs, while supporting jobs and local supply chains across the north of Scotland.
“We will continue to work closely with landowners, local communities, marine users and other stakeholders as activity continues onshore and offshore in the months ahead.”