Italy-headquartered Prysmian has concluded the installation of submarine and land power cables to connect the 450 MW Neart na Gaoithe offshore wind farm to the Scottish mainland power grid.
The offshore wind project is now in the testing and commissioning phase and the system is scheduled to go live during 2024.
Prysmian designed, supplied, and installed two HVAC 220 kV three-core extruded export submarine cables with single-wire armoring which reach land at Thorntonloch beach in East Lothian.
The company also provided two 220 kV extruded land cable circuits that link the landfall area to the substation at Crystal Rig and two 400 kV extruded land cable circuits to link the Crystal Rig substation to a Scottish Power substation.
“Prysmian managed complex scopes such as the sea-land cable landing, the laying and burial of the cables, the pulling of the cables onto the offshore platform and the termination of the cables all within its scope. This required major effort spent on interfacing with other packages working on the project,” said Lubna Gemey , Project Manager for the offshore activities.
The submarine cables were manufactured at Prysmian’s center of excellence in Pikkala, Finland, while the land cables were produced in Gron, France.
The marine cable laying work was performed by the company’s Cable Enterprise vessel, while the burial campaign was carried out by the Normand Pacific .
The Cable Enterprise also managed the pulling of the cables on the platform.
“We are proud to have delivered the project matching the required quality but most of all reaching the heaviest possible health and safety results, with 0 LTI (lost time injury) registered in over 600,000 worked manhours,” said Massimo Galleta , Project Director.
Among the challenges Prysmian encountered during the project was the need to coordinate with many other companies involved, the firm said.
The wind turbines for Neart na Gaoithe are produced by Siemens Gamesa , the foundations are by Saipem , and the substations are supplied by GE.
“ On the offshore platforms, we were working in a confined space with the other contractors, making sure that things were going smoothly, also considering the simultaneous operations that were being performed. This required strong planning to collaborate efficiently and meet time requirements, a good attitude, and close cooperation ,” said Gemey.
“Another technical challenge faced by Prysmian during the project was related to the sea-land horizontal directional drilling (HDD), a 600 meter pipe installed on the sea-land transition area that allowed the cable to pass from offshore to the land ,” said Galleta.
“ Prysmian employed a new method for installing the pipe, which was pushed from the shore instead of being pulled from offshore, in order to limit the engagement of the offshore spread always subjected to weather constraints. “
Cable burial activities at the inter-array routes within the Neart na Gaoithe offshore wind farm were done in March 2024, following the completion of cable installation works in January.
Located 15 kilometers off the coast of Fife in Scotland, the 450 MW Neart na Gaoithe offshore wind farm will feature 54 Siemens Gamesa 8 MW wind turbines.
The project, owned by the joint venture between EDF Renewables and ESB, is expected to produce its first power this year.