About the East Anglia ONE offshore windfarm
Located off the coast of Norfolk and Suffolk, UK, the East Anglia offshore wind area has been earmarked for future development. The first area, developed by ScottishPower Renewables, was awarded a license as part of the Round 3 category, and is referred to as “East Anglia ONE”, covers an area of approximately 200km2, and is located towards the south of the development area.
At present, the £2.5bn East Anglia ONE will consist of 102 Siemens Gamesa 7MW wind turbines, giving an overall generating capacity of up to 714 megawatts, which is enough for over half a million homes. An offshore substation platform and its foundations are being built to collect the electricity from the turbines and transform it to a form suitable for transfer to shore for connection to the National Grid.
Two seabed export cables, each around 73 km in length, will transfer the electricity to a landfall site at Bawdsey, Suffolk.
“The work carried out by Bibby HydroMap was of key importance for the progress of the EAONE installation campaign. The quality and efficiency of the works was reflected not only during the fieldwork stages, when the different vessels worked under demanding conditions and to very high standards of HSE and technical specifications, but also during the data processing stages, enabling the management and processing of the large amounts of acquired data subsequently delivered as requested and responding efficiently to the project’s demands and priorities.”
Luis Costa, Lead Geotechnical Engineer
Scottish Power Renewables
2017/18 Marine Survey
In December 2017, Bibby HydroMap were commissioned by ScottishPower Renewables to undertake a geophysical and UXO survey across the proposed site to ensure items which could pose a risk to construction operations were identified.
The objectives of the survey were to provide detailed information on:
Seabed bathymetry, morphology and features across the site
Man-made or geological hazards that could impair the installation phase
Seabed conditions or hazards to the installation
Any objects that model as potential UXO
The survey was carried out by Bibby HydroMap’s own survey vessels Bibby Athena, Bibby Tethra and Lia. FeliX, a dedicated survey vessel owned and operated by iXblue, also carried out survey operations across the site.
With challenging seabed morphology and significant tidal currents across the site, ScottishPower Renewables approached Bibby HydroMap to ensure survey data was acquired, processed and delivered as soon as possible.
To complete the survey within the short timeframe, four specialist survey vessels were mobilised to site, each of which were mobilised with dual-head multibeam echosounder systems, high resolution side scan sonar towfish and a multiple magnetometer array. All sensors were acquired simultaneously to ensure maximum coverage.
The main challenge came in the form of how to obtain full, accurate UXO data coverage across the site, given the difficult site conditions. Equipping Bibby Tethra, Bibby Athena and FeliX with multiple EIVA ScanFish Katria ROTV systems enabled multiple magnetometers to be flown at a fixed height above the seabed. The terrain following mode of the ScanFish, coupled with the unique deployment and towing configuration, enabled high quality data to be collected with limited need for infill, despite the difficult environmental conditions.
Following successful acquisition, all data was processed and interpreted in-house using Geosoft’s Oasis Montaj UX Detect. With a long track record in UXO survey data handling, Bibby HydroMap have worked closely with Geosoft to develop a number of specialist algorithms to ensure the highest quality UXO data processing and delivery. All data was appraised and processed in conjunction with ScottishPower Renewables dedicated UXO consultant, RPS Energy, to ensure that all data met the high quality required for UXO detection.
Rather than moving whole heartedly towards automated target picking, we are certain that our manual technique using highly trained processing geophysicists has reduced the number of false positives, reducing valuable inspection time and offering a high success rate of detection.