Monopile Installation on Dogger Bank B Delayed by Six Months

Wind Farm Update

January 18, 2024, by Adrijana Buljan

NOTE: The article was amended on 23 January to include the parts of Dogger Bank Wind Farm’s Supporting Statement filed to the Marine Management Organisation (MMO) that concern the reasons for the delay of the monopile installation on Dogger Bank B.

The installation of foundations on two UK offshore wind projects, the 1.4 GW Sofia and the 1.2 GW Dogger Bank B, the second phase of the 3.6 GW Dogger Bank Wind Farm, is scheduled to start soon.

On the first 1.2 GW phase of the Dogger Bank Wind Farm, Dogger Bank A, all 95 monopile foundations have been installed with wind turbine installation well underway. The wind farm produced first power in October 2023.

Monopile installation on the 1.2 GW Dogger Bank B was scheduled to start in September 2023, but the campaign was delayed and is now expected to start in March, according to filings available on the UK government’s website, submitted by the Dogger Bank Wind Farm consortium (SSE Renewables, Equinor and Vårgrønn) in November 2023.

Namely, Dogger Bank Wind Farm requested a variation in the underwater noise (UWN) monitoring plan from the UK’s Marine Management Organisation (MMO) as the installation of the monopiles that were meant to be subject to UWN monitoring will now coincide with the same work on the nearby Sofia offshore wind farm, which could contaminate the results.

“The DBB monopile foundation installation campaign (and the UWN monitoring of the foundations that would accompany this) was originally scheduled to commence in September 2023. However, due to various reasons, the DBB campaign will now commence in March 2024. Unavoidable piling delays were incurred after a mechanical fault in the monopile lifting tool was discovered following the Dogger Bank A (DBA) foundation installation campaign. As a result, the campaign will now coincide with the installation of foundations at the nearby Sofia Offshore Wind Farm (SOWF), which is scheduled to commence piling in January 2024,” Dogger Bank Wind Farm said in the Supporting Statement filed with the request.

“Furthermore, the piling vessel Strashnov has demobilised for essential planned maintenance, after which she is contracted for a separate job in Angola over the winter period. It may be that the either of these activities are delayed, in which case she will be coming onto site at a later date, a scenario over which the Project has no control and, as such, will require more detailed coordination with SOWF.”

MMO approved Dogger Bank Wind Farm’s request on 17 January, allowing for some flexibility in selecting which foundations will be monitored for underwater noise.

As already mentioned, the monopile installation work on the Sofia project site, also being built on Dogger Bank in the central North Sea, is expected to start this month. The monopiles are being produced by EEW and will be installed by Van Oord, the project’s EPCI contractor for the inter-array cables and monopile foundations.

The 1.4 GW Sofia offshore wind farm, owned and developed by RWE, will feature 100 Siemens Gamesa SG 14-222 DD wind turbines, 44 of which will be equipped with 108-metre-long recyclable blades. The offshore wind farm is scheduled to be fully commissioned in 2026.

For Dogger Bank B, the foundations are being delivered by the consortium of Sif Netherlands and Smulders Projects Belgium, under a contract signed in 2020 for the first two phases of the Dogger Bank Wind Farm.

The foundation installation at Dogger Bank A & B is being carried out by Seaway 7, supported by DEME as a subcontractor.

The first two 1.2 GW phases of the 3.6 GW Dogger Bank Wind Farm, Dogger Bank A and Dogger Bank B, will comprise 95 Haliade-X 13 MW turbines each. The third phase, Dogger Bank C, will feature 87 Haliade-X 14 MW turbines.

Once completed in 2026, the project will generate enough electricity to power up to 6 million households in the UK.