Theo de Lange, Commercial Manager, Van Oord Offshore Wind Projects, says that despite some delayed projects, Europe’s Offshore Wind cable-laying demand is expected to grow rapidly. “UK Round 3 projects, but also German and probably also Dutch projects, are moving farther away from shore, into deeper waters. That means those vessels doing the cable-laying need to be suitable for rougher conditions.”

To meet these challenges, contractors are placing orders for new cable-laying vessels or ship conversion projects. Van Oord, which has relied on its own adapted side-stone dumpers or on chartered vessels, decided to invest in its own purpose-built cable-laying vessel – part of Van Oord’s business model as offshore wind EPC contractor – “building the complete balance of plant of wind farms, and at the same time doing that with our own equipment.” Van Oord had a clear set of requirements for its new cable-laying vessel, including accommodation, dynamic positioning capabilities and the ship’s dimensions, but also faced a relatively short timeframe before mobilizing her for Gemini. The team looked at vessel conversion options and existing Offshore Support Vessel designs, but found these too limiting. When presented with the Damen Offshore Carrier 8500 concept, Van Oord quickly decided to order Nexus, the first in class for Damen’s new multipurpose design.

“Damen’s concept was probably originally made for transportation and installation purposes,” Theo De Lange says. “So the start was different from, for example, a dedicated offshore vessel with all kinds of capabilities that probably we don’t need for cable-laying. The Damen concept was kind of a basic design with flat deck, enough accommodation and enough deck space. That was the perfect basis for making it a cable-laying vessel.” Because the engineering for the basic design was close to completion, it was possible for Damen to build the vessel in what De Lange says is a very short timeframe. “They also offered a reasonable price/performance balance. And of course Damen has a good track record. That gave us enough confidence that this project would also be delivered in time,” De Lange said.

Despite the demanding deadline, Damen undertook additional engineering to fit Van Oord’s specifications. The main challenge was extending the accommodation without losing too much deck space, while maintaining low noise and vibrations and certified comfort class for up to 90 persons. “A high accommodation standard is very important,” says De Lange. “Not only for Van Oord personnel, but there will be suppliers on board like cable companies and testing teams. So you have all kind of requirements from clients and suppliers that we also had to comply with. I think this vessel at the moment is perfectly suitable for the majority of Round 3 projects. It’s definitely capable of installing the export cables, but without any problems we could also do the infield cables. Most probably it will also do some infield cable-laying for Gemini,” De Lange added.