The Belgium-based company, DEME Offshore, installed the last of Parkwind’s Arcadis Ost 1 offshore wind farm’s 28 monopiles. This was the Orion floating installation vessel’s first project. These XXL monopiles are the largest monopile foundations ever installed.

The Arcadis Ost 1 offshore wind farm is located off the coast of Rügen, Germany’s largest island in the Baltic sea. It is being developed by the Belgian company, Parkwind, in collaboration with PMV and OstseeWindEnergie. The 257 MW wind farm is Parkwind’s first offshore wind farm outside Belgium and should supply enough renewable energy to power 290,000 households, once it begins operations in 2023.

Due to the size of the XXL monopiles, weighing over 2,000 tonnes, and measuring 9.5 metres in diameter and 110 metres in length, and the difficult conditions, due to water depths of up to 45 m and challenging soil conditions, a new set of specialist tools were put to use during this project.

The Offshore Heavy Lift DP3 Installation Vessel, Orion, built in 2019,  has a length of 216.50 metres, a 49.00-metre beam, and a depth of 16.80 metres. During this installation campaign, the ship ran on Liquefied natural gas (LNG). Its crane has a main capacity of 5,000-tonne and an auxiliary capacity of 1,500 tonnes.

The Orion’s tailor-made, motion compensated pile gripper system allowed the ship’s crew to handle the monopiles, transported on deck horizontally. The motion compensated gripper and the vessel’s DP3 capability were used to keep the monopiles stable despite waves. Other tools used in the installation process include an adjustable monopile sea fastening system, an automated monopile lifting spreader beam for horizontal lifting, automated quick-lift tools to avoid manual handling, and noise mitigation systems.

Now that the monopiles are in place, the secondary steel structures will be installed next, to complete the Arcadis Ost 1 offshore wind farm foundations. Later this year, the 27 Vestas V 174 – 9,5 MW wind turbines will also be installed.