Van Oord’s offshore installation vessel Aeolus is ready to start the installation of the first of 62 jacket foundations for the French Saint-Brieuc offshore wind farm project. The vessel underwent an upgrade and an extensive spread of project-specific installation equipment was placed on deck to make it suitable for the installation campaign which is to be executed in 2021 and 2022.
The Saint-Brieuc project, owned by Ailes Marine (100 % Iberdrola) is located 16,3 kilometres off the coast of Brittany and has a total capacity of 496 MW. The wind farm will feature 62 Siemens Gamesa 8 MW wind turbines. Van Oord was awarded the contract last year to transport and install the 62 jacket foundations for the wind turbines (3 pin piles each) and the 4 foundation pin piles for the offshore substation. A total of 190 pin piles will be installed. Before the start of the operations in France, equipment was engineered, constructed and extensively tested.
The Aeolus (2014) has a lifting capacity of more than 1,600 tonnes. Its jacking system with its four giant legs, each measuring 85 metres and weighing 1,280 tonnes, allow Aeolus to be jacked up and to work in waters of up to 45 metres deep.
Modifications
Due to the geotechnical circumstances in the Bay of Saint-Brieuc, harsh weather conditions combined with extremely strong currents, heavy Atlantic swell and very high waves, offshore operations are possible only between March and October.
To ensure that the Aeolus can be safely jacked up above sea level the lifting spuds were modified with a flex-pin construction. For the drilling operations, new hydraulic drills were engineered and built to handle all types of soil and rock conditions. A newly designed and created state-of-the-art drilling template will function as a positioning and holding-tool to ensure the precise placement of the pin-piles.
Van Oord will use the port of Cherbourg as the pin pile marshalling port. The pin piles, coming from Navantia-Windar in Spain, will be stored in France before installation offshore. The company will also be deploying several other vessels on the project in the next months for the removal of boulders, installation of scour protection, transport of pin piles, etc. The installation campaign for the pin piles will be executed in 2021 and 2022. In 2022 the jackets will also be installed. Source: Van Oord
