Cobra

On behalf of Prysmian Group, De Romein Group undertook work for the installation of the COBRA cable along the Waddenweg in Eemshaven and successfully completed the project.

In this project, De Romein Group was responsible for the work involved in bringing the COBRA cable from offshore to onshore: an electric cable running from Denmark to Eemshaven. This cable serves as the final connection between a wind farm located off the coast of Denmark and the TenneT Station in Eemshaven. The installation of this cable garnered national news coverage.

Our Expertise

We executed cable works in a tidal area. We installed the cable through a primary dike, using an open excavation method.

For this project, we performed the following tasks:

• Excavation for 2 320 kV HVDC cables with a length of 2600 meters
• Installation of 2 320 kV HVDC cables, each 2600 meters long
• Excavation and preparation of a jointing pit between the sea cables and land cables
• Conducting 3 HDD (Horizontal Directional Drilling) bores Ø225 mm over a length of 210 meters
• Excavation and restoration of a primary dike to its original state
• Removal and reinstallation of riprap and basalt blocks from the primary dike
• Removal and installation of penetrated breakstone for the final covering of a primary dike
• Establishment and maintenance of temporary dike protection using a sheet pile construction
• Supply, mirror welding, and installation of 2 casing pipes Ø450 mm for the passage of 2 320 kV HVDC cables through the primary dike
• Supply, mirror welding, and installation of 1 casing pipe Ø140 mm for the passage of fiber optic cable through the primary dike
• Breaking up asphalt pavements from roads and primary dike coverings
• Supply and installation of asphalt pavements for road structures and primary dike coverings

Sustainability

Through this project, we contributed to the realization of a sustainable energy source.