Mammoet wins big wind farm transport contract

Self propelled modular transporter (SPMT) is indispensable for offshore wind component marshalling. Photo: Mammoet

A major contract win for Mammoet will see it marshall giant tubular steel foundations for RWE’s Nordseecluster A and Thor offshore wind farms. They are two of the largest in Europe.

Thor is off the coast of Denmark and the other off the coast of Germany, both in the North Sea.

Mammoet will lift and move and otherwise handle more than 100 XL monopile foundations for the offshore wind turbines. The job will last around a year.

The Netherlands-headquartered global heavy lift and transport specialist’s contract is with Hamburg, Germany-based Buss Ports, owner of Buss Terminal Eemshaven.

Nordseecluster has a planned capacity of 1.6 gigawatts. It will be constructed in two phases (A & B). Thor’s capacity of more than 1 GW will be enough to power more than a million homes. It will be Denmark’s biggest.

Scope of work

Largest of the foundations that will be moved on SPMT will be 96 metres long and weigh 1,700 tonnes. Photo: Mammoet

Work for Mammoet begins with managing the load-in, storage and load-out of a total of 116 XL monopiles for both wind farm projects at Buss Terminal Eemshaven in the Netherlands. XL monopiles are 6 to 8 metres in diameter. Largest of these foundations on this job will weigh 1,700 tonnes and be 96 metres long.

For the Thor wind farm there are 72 foundations, each weighing up to 1,500 tonnes and 100 metres long.

For this part of the operation the monopiles will be lying horizontally. They are offloaded from a delivery ship onto the quay using a roll on, roll off (ro-ro) linkspan ramp. Transport is on self propelled modular transporter (SPMT) on which the round monopiles will sit in specially shaped saddles.

For transporting XXL monopiles (8 to 13 metres in diameter) Mammoet has developed a special jacking cradle but it won’t be needed for these smaller XL monopiles on this job. Smaller still are regular monopiles – these are “only” 5 or 6 metres in diameter.

From the quay the XL monopiles will be transported to a storage area where they will wait to be called off for later shipping to the offshore wind farm construction sites. Thor is 22 km west off the coast of Jutland.

Commenting on the project Wouter Santen, Mammoet project manager, said, “This is a complex marshalling operation, with large components for both farms needing to be moved and managed on a single site.

“Combining our specialist heavy transport equipment with our engineering experience of monopile handling, we are delighted to support the development of these significant offshore wind projects concurrently.”

For his part Marc Wegman, Buss Terminal Eemshaven managing director, said, “Mammoet has a proven track record for managing the movement of monopiles safely and efficiently. Having them by our side during the planning stage has been invaluable. We look forward to working with them as we move into the assembly phase.”

In 2025 the foundations will be loaded out and shipped to site for installation.

Mammoet will transport 116 monopile foundations for the Nordseecluster A and Thor offshore wind farms. Photo: Mammoet