Tennet advances Dutch wind farm project as bulker collision causes limited damage to platform foundation

Transmission grid operator TenneT has determined that there was no major damage to the platform jacket foundation of the 1.5 GW Hollandse Kust Zuid offshore wind farm that was struck by the adrift 37,200 dwt bulker Julietta D earlier this year.

“The investigation shows that the damage to the jacket is limited. The damaged parts of the jacket can be repaired at a later stage after topside installation,” TenneT said in a statement, adding that it expects the topside to be installed at the end of March or early April.

The Maltese-flagged ship, which initially collided with a product tanker, Pechora Star, off the Dutch coast near Ijmuiden port after its anchor failed to hold, was abandoned by its crew and drifted in the storm-ravaged North Sea before hitting the jacket. No one was working on the platform at that time.

Tennet said the incident was limited to paint damage and a few dents on one of the legs of the platform, and damage to one of the four landing platforms for working vessels. In addition to the inspection of visible damage above water, underwater investigations were also carried out to determine any damage to the substructure.

Joris Engelen, TenneT’s platform project lead, added: “When designing and building our jackets, scenarios are taken into account that a ship of limited size may collide with the jacket. After the initial fright of the collision, we set up and implemented an extensive investigation plan in cooperation with the parties involved. The jacket is expected to be in operation for many years. We are therefore relieved that the inspections and the investigations show that we can install the top side of the transformer platform on the jacket safely and as scheduled.”