Installation of foundations

Belgian construction company DEME and the Port of Thyboron have signed a contract regarding the installation of foundations for Vattenfall’s Vesterhav Nord and Syd offshore wind farms. Installation of the 41 foundations, to support the 8.4 MW Siemens Gamesa offshore wind turbines, will therefore be handled from the Port of Thyboron.

The foundations that DEME will be installing are the large steel structures of 41 monopiles and TPs. The 77 m long monopiles, each weighing around 622 tonnes, will be produced by EEW in Rostock, Germany. The associated transition pieces (TPs) between the monopiles and the turbines will be produced in Aalborg by Bladt Industries A/S. Each TP will be 22.5 m high and weigh 275 tonnes. The large foundations will be shipped in sets to the Port of Thyboron on barges during spring. DEME’s large installation vessel, Innovation – which is 147.5 m long and 42 m wide – will regularly sail into the Port of Thyboron to load foundations, and then out to the offshore wind farms in the North Sea to install them.

Ample space for the work

DEME’s project manager, Jan Van de Velde, sees great opportunities in the project quay at the Port of Thyboron, with solid heavy-lift facilities and lots of quayside space. He notes: “There are clear advantages in the fact that we can work undisturbed at the quay in Thyboron throughout the installation project, and without disturbing others as we work at the port.”

The installation vessel works 24/7 when weather conditions allow, handling the large, heavy foundations during an installation project. It is therefore an advantage that the Port of Thyboron’s project quay facilities are located in a closed harbour area, far from the city centre.

The safe navigation in any weather due to the port’s naturally protected location inside the Liim Fiord, and a fairway with absolutely no queues, were equally key factors in choosing the Port of Thyboron for installation of the foundations. Installation vessels are very cost-intensive. It is therefore crucial that the project can be run without disruption throughout the installation. Installation vessels do not wait, except in cases of force majeure.

Enthusiastic captains

The captains of the installation vessel are also enthusiastic about the Port of Thyboron having been chosen as the marshalling port. They feel very comfortable about the harbour entrance, and see it as an advantage that they do not have to sail across currents to call at port at the project quay in the Port of Thyboron. The project quay lies parallel to the currents in the Liim Fiord.

Good North Sea location

The port’s close proximity to the offshore wind farms clearly maximises project efficiency. Vesterhav Nord will be installed 5.5-8.4 km offshore, slightly south of Thyboron, and Vesterhav Syd will be installed north of Hvide Sande, 9-10 km offshore. Being able to ship the foundations to a port that is near at hand reduces the distance the installation vessel has to sail, to the benefit of the project timetable and budget, and not least the environment.

DEME pushes port towards the future

This is the first time such a large offshore wind farm installation project will be serviced from the Port of Thyboron. By choosing the Port of Thyboron for the installation, DEME and Vattenfall AB are actively contributing to the expansion of port capacity near the North Sea, in relation to the future need for large quayside areas and deep water in the offshore wind energy sector. There has been close dialogue and trustful and open cooperation between DEME and the Port of Thyboron on the project for a long time.

It is part of the Port of Thyboron’s strategy to develop the port in close cooperation with its users. The close cooperation with DEME during this project has given the Port of Thyboron a valuable foundation for yet another expansion that supports the sector. This has resulted in the establishment of a new 11 m deep fairway from the North Sea all the way to the offshore project quay facilities at the port.

“As a port, we have found DEME to be a very professional and serious partner who has helped push us the last mile. In all modesty, we have also shown that a port like Thyboron can deliver the conditions we have promised. We are proud of this,” says Director Jesper Holt Jensen from the Port of Thyboron. “When Innovation arrives probable on 18 February to pick up the first 4 foundations for Vesterhav Nord and Syd, it will be a day of celebration at the Port of Thyboron.”

Jan Van de Velde, from DEME reports: “At Vattenfall´s business-to-business meeting with potential local suppliers in Thyboron, we perceived a potential to optimise the installation project using the good project quay facilities we saw with our own eyes during our visit. The Port of Thyboron has some unique port facilities for offshore installation. The open dialogue we have been able to have with the Port of Thyboron about the project preparations has also been outstanding. Our engineers have prepared everything down to the smallest detail. We are fully at ease about being the first to operate on such a large scale at the Port of Thyboron, and are pleased to be able to advance development through our choice of port and contribute to greater port capacity for the many projects being planned for the North Sea in the future.”

The Port of Thyboron currently offers 300,000 m2 of quayside land for storing primary components, a quay with a load bearing capacity of up to 23 tonnes per square metre, and now also a channel up to 11 m deep from the North Sea to the project quay facilities in Sydhavnen. Given the port’s location as a natural harbour inside the Liim Fiord, it has further potential for greater capacity in the form of port expansions that add more quayside land and quays in the long term.

Three major new records for the Port of Thyboron

This installation project moves the Port of Thyboron into another league. The first offshore wind farm, Nissum Bredning, has already been installed from the Port of Thyboron, and several large onshore wind turbines have also been handled at the port. The heavy transformer lifts have been efficiently executed. The offshore wind energy segment has been generally stable at the port every year since 2017, with all kinds of seabed surveys and various offshore vessel mobilisations and demobilisations. Several offshore shipping companies use Thyboron as their home port, including Offshore Windservice A/S with Fob Swath vessels, underwater construction specialist JD-Contractor A/S, which has home ports in Kalundborg and Thyboron, and Northern Survey A/S uses the port on a regular basis for their vessels and has qualified maritime service done here in the winter season. But this is the first time in the port’s more than 100-year history that an installation vessel as large as Innovation has called at port, that such heavy lifts have to be performed via jack up (where the ship rises up on four pillars as the crane loads the vessel), and that such a large scale offshore wind farm will be installed from the Port of Thyboron.

“It is a major project, in full production scale, which we have fully enjoyed preparing for and look forward to delivering on,” says Tine Jensen Le Breton, from the Port of Thyboron, who has run the entire project in close collaboration with DEME’s project team. “Good service and our flexible and service-minded approach in Thyboron have been key for the project. Not a single task has arisen that could not be handled in Thyboron during the preparations. The more than 100 local companies have a solution-oriented focus and are extremely service-minded. It was even possible to provide COVID-19 tests (at a time when Denmark has reduced testing to virtually nil) through a joint effort in Thyboron, where cooperation is an art that dates back to the port’s establishment in 1914, more than one hundred years ago. It lies in the DNA of the whole town to pull together, and it is a real pleasure to be part of it.”

At the start of the installation project, the Port of Thyboron, Vattenfall AB and DEME will invite people to tour the project quay in buses while the installation vessel is in port. DEME will be on hand to talk about the large installation project. Follow the Port of Thyboron on Facebook, Linked In and Instagram regarding this and the tour dates and times.