The installation of the first foundations for 277 wind turbines at Dogger Bank Wind Farm in the North Sea has commenced this week.

The windfarm, which will be located more than 130km off the North East coast of England, will be the largest offshore windfarm and when operational will generate 3.6GW of energy – enough to power 6M UK homes annually on completion.

Dogger Bank Wind Farm, a joint venture between SSE Renewables (40%), Equinor (40%) and Eni Plenitude (20%), is made up of three offshore windfarm sites in the North Sea. SSE Renewables is lead operator for the development and construction of Dogger Bank Wind Farm, while Equinor will be lead operator of the windfarm on completion for its expected operational life of around 35 years.

The installation of the first monopile and transition piece at Dogger Bank A marks a significant milestone in the project.

The foundations, designed by UK-based designers from Wood Thilsted, are up to 72m in length, weigh on average 1,057t and include the world’s largest 8m offshore wind flange. The design includes the world’s first split-level transition piece for safe installation and operation, with installation works being led by Seaway supported by Deme.

Installation of GE Renewable Energy’s ground-breaking Haliade-X turbines onto each of the installed turbine foundations will commence from spring 2023.

"Today we are delighted to announce that we’ve installed the first turbine foundation monopile and transition piece at our flagship Dogger Bank offshore wind project in the North Sea. This is a really important milestone for the project as it marks the commencement of our campaign to install 277 turbine foundations across the three phases of what will be the world’s largest offshore windfarm.

SSE Renewables director of offshore wind Paul Cooley said: “At SSE Renewables, we’re already building more offshore wind energy than any other company in the world. As lead operator during the construction phase of Dogger Bank Wind Farm, we’re working with our development and supply chain partners to install some of the world’s largest turbine foundations on this world-class project.”

The foundations have been optimised to tackle challenging wave loads in the Dogger Bank area of the North Sea, with installation in water depths of up to 32m and at a distance of 130km from shore.

Over the three-year installation programme for the three phases of Dogger Bank Wind Farm, a total of 277 monopiles and transition pieces will be loaded onto installation vessels in Rotterdam ahead of transfer out to the offshore windfarm site deep into the North Sea. Using dynamic positioning technology, the vessels will pinpoint the installation site in the seabed at which point a monopile measuring up to 72m will be upended and transferred to a pile gripper, before being lowered into the seabed.

A hammer will be used to drive the monopile to the design depth in the seabed before a guidance system aligns the installation of the record-breaking 8m flanges which act as a connection for the transition piece which is then installed onto the monopile. The foundations require 152 giant M80 bolts to secure them before a cover is inserted onto the top of the transition piece to leave it watertight.

Seaway 7 was awarded the tier one contract for foundation installation on all three phases of Dogger Bank Wind Farm, with sub-contractor Deme deploying its Innovation vessel for installation of the first foundations on Dogger Bank A.

Like what you've read? To receive New Civil Engineer's daily and weekly newsletters click here.

Tagged with: Dogger Bank SSE

Sign in or Register a new account to join the discussion.