The Rampion Offshore Wind Farm (ROWF) is located in the English Channel, approximately 13km offshore Sussex coast. The wind farm consists of 116 wind turbines, installed at water depths between 19m and 40m. The maximum total output is 400MW and the electrical power is collected in one offshore substation and transmitted to the landing site near Worthing via two (2) 150kV 3-core HVAC export submarine power cables, approximately 16.5 km long. The aforementioned export cables were installed in 2016

Due to faults found in both these original export cables shortly after installation, the Owner decided to replace these by two (2) new cables along the same route.

Assodivers Group was awarded the installation and protection, by means of post-lay jetting and trenching, of the 4th export cable (2nd replacement cable, or Cable No.4) which installed on the west of the initial cable routes.


Vessel / Equipment used

  • Atalanti
  • Artemis
  • Astrea
  • Venom 3k – 6000T
  • AssoTrencher IV Mk6
  • Atom ROV

Project Specifications

Rampion OWF - Export Cable 4

Assodivers Group
Cable Type:
150kV HVAC 3-core Al
Cable Weight:
Weigh in air: 81.7 kg/m Weigh in water: 55.8 kg/m
Cable Diameter:
230 mm
Service Provided:
Cable Transportation – Landing – Pull-in on platform – Installation – Protection
Rampion Offshore Wind Ltd
Trenching Length & Burial Depth:
12,530 m @ 1.0 m
Jetting Length & Burial Depth:
1,090 m @ 1.0 m
Alternative Protection:
Pre-excavation and reinstatement: 1,800m @ 2.0m
English Channel
Max Water Depth:
25 m