Fraunhofer IWES and Fugro have completed the geophysical site characterisation of the N-9.5 offshore wind area in the German North Sea, a zone planned to host up to 1 gigawatt (GW) of capacity, the partners said.
The work was carried out for Germany’s Federal Maritime and Hydrographic Agency (BSH) and included the acquisition of both sub-bottom profiler data and ultra-high-resolution multichannel seismic measurements to assess different depth ranges beneath the seabed.
The partners said the sub-bottom profiler provided high-resolution images of sediments and geological structures down to about 15 metres, while the seismic dataset mapped larger sediment bodies and subsurface structures to depths of roughly 200 metres. After integrating the datasets, a preliminary interpretation of subsurface conditions was produced.
“As part of the central preliminary site investigation, the preliminary interpretation provides us with a valuable planning basis for the preliminary geotechnical investigation and forms the starting point for the development of an engineering geological model,” said Marcel Ruhnau, coordinator of geophysical site investigation at BSH.
Ruhnau added that the data will also support later geotechnical work and help reduce construction risks for the planned offshore wind farm.
“It is vital that OWF developers and their engineers are provided with precise geological information to enable them to make informed decisions and plan accordingly,” Fugro project manager Manfred Stender said. “This will ultimately reduce costly project delays and contribute to the development of the wind farm.”
Under Germany’s site development plan dated Jan. 30, 2025, the 146-square-kilometre N-9.5 area is slated to add 1 GW of capacity to the country’s offshore grid.
Fugro acted as main contractor, providing the survey vessel Fugro Discovery and managing the acquisition, processing and interpretation of the sub-bottom profiler data. Fraunhofer IWES, as subcontractor, acquired, processed and interpreted the seismic dataset with personnel support from Jesley Geoservices.
“The successful completion of this project marks our eight consecutive years of conducting an UHR MCS campaign for the BSH in the German North Sea,” said Tim Burmeister, project manager at Fraunhofer IWES.
“We have been working with Fugro on preliminary geophysical site investigations of offshore wind farm planning areas for six years now. Thanks to our long-standing partnership with Fugro, we have a deep understanding of our shared goals and processes,” he added, saying the institute’s work supports Germany’s energy transition.
