Pre-Construction Surveys Starting at 2.4 GW Hornsea Four Offshore Wind Farm Site

March 10, 2025, by Adrijana Buljan

As part of the pre-construction works at the Hornsea Four offshore wind farm site in the UK, Ørsted will carry out a geophysical survey campaign, starting in late March/early April, to investigate the physical characteristics of the seabed.

The data acquired from the campaign will be used for detailed foundation design and installation activities, jack-up vessel and cable installation assessments.

The geophysical surveys will be conducted by the survey vessels Ocean Endeavour, Titan Endeavour, and Ocean Researcher as well as the support vessel GV Jacoba.

The survey equipment will include a multibeam echosounder (MBES)/ Backscatter, side scan sonar (SSS), magnetometer, Innomar sub-bottom profilers (SBPs) and an ultra-short baseline (USBL) acoustic positioning system to calculate the position of underwater targets.

The mobilisation of the first geophysical survey vessel will start on 14 March and the work at the offshore site will start around 1 April. The campaign is expected to last approximately 180 days, including weather downtime, according to a Notice to Mariners from the project.

Geophysical survey work at the Hornsea Four site is coming up after geotechnical surveys started last month.

Geotechnical Surveys to Start at Hornsea Four Site in February

Project Updates

Located 69 kilometres off the Yorkshire coast, the Hornsea Four offshore wind farm is planned to have an installed capacity of 2.4 GW.

The project was granted consent by the Secretary of State for the Department of Energy Security and Net Zero in July 2023 and Ørsted secured a Contract for Difference (CfD) for the offshore wind farm from the UK government in September 2024.

In September last year, Ørsted said the company expected to take the final investment decision on Hornsea Four within 18 months and was targeting the commissioning of the project before the end of 2030.