Supplier Agreement Signals Major Step Forward for Subsea HVDC Projects

SSEN Transmission has signed supplier agreements with cable supplier NKT to deliver two HVDC transmission connection projects.

The agreements will help NKT to proceed with the initial works on projects connecting Lewis on the Western Isles to Beauly on the Scottish mainland and Spittal in Caithness to Peterhead in Aberdeenshire.

The Western Isles connection project will include installation of 81 km of subsea cable and a further 80 km of underground cable between the HVDC site on Lewis and the corresponding HVDC site at Fanellan on the mainland, while the Spittal to Peterhead connection comprises of a 150 km subsea cable.

The projects will also require land cable sections and new associated HVDC convertor stations. Both connection projects will utilize 525kv HVDC cable with Bi Pole design due to the long conductor lengths. An additional DMR (dedicated metallic return) cable will be installed on the Spittal to Peterhead connection.

The projects are part of SSEN Transmission’s infrastructure development program, a $25.95 billion investment to deliver major upgrades to the electricity transmission network in the north of Scotland for connection and transportation of renewable energy around Great Britain.