Heerema Marine Contractors has installed, together with its client Delft Offshore Turbine (DOT) and their subcontractor CAPE Holland, the DOT monopile at the Eneco Amalia windpark.
During the installation of the monopile a relatively new driving technology was used by CAPE Holland in combination with a new installation operation by Heerema's offshore lift vessel Aegir. The monopile was vibrated into the soil with a Vibro Lifting Tool which is a hybrid of a vibro hammer and lifting tool. Because of this no other tools were needed for picking up, upending and driving the pile to final penetration. By measuring the verticality during driving, the vessel and crane were able to control the verticality while operating in DP mode.
The installation by Heerema's Aegir was performed in floating mode on DP and with the monopile free hanging from the hook of the crane. No motion compensation frame from the vessel was used during the installation of the monopile. As a result of this operation the monopile is installed within the target box of 0.5m and has an inclination of 0.3 degrees with less required hardware.