German grid operator, Transpower Stromübertragungs GmbH has awarded subsea cable specialist, Offshore Marine Management (OMM) the contract to install the HVAC cables connecting the Bard Offshore 1 and BorWin alpha platforms for the BorWin1 project.
BorWin1 is the world's largest offshore wind farm cluster, located off the coast of Germany, OMM's role will be to install the two infield HVAC cables between the principle platforms. From the BorWin alpha platform the export cables continue to the Island of Norderney and onward to Diele where power will enter the German grid.
This is a major installation project award for OMM encompassing key facets of the company's subsea portfolio and capabilities. OMM will manage the complete process, from the expansive preparatory works and installation through to the post cable burial survey and final client deliverables.
Operations will be conducted from a state-of-the-art, multiple support DP2 vessel manned with OMM survey and cable teams. Hallin Marine and Modus have been selected as sub-contractors, supplying specialised vessels and equipment. The scope of work will include inspections of the J-tubes, visual route and platform inspections with OMM's specially-designed software package, pre-lay grapnel runs and full topside preparatory works on both platforms for the J-tube pull in operations.
OMM will supply two topside teams for the pull in works, including all required equipment, and will then lay and monitor the two (208mm OD) 1.1km HVAC cables along the proposed routes between the platforms at a water depth of approximately 40m.
Rob Grimmond, OMM Managing Director, said the work was won from the company's European office in Bremen, Germany, but will primarily be directed from its operational office in Cambridge, England. The Bremen office will be used for operations during key phases.
"This contract is a major success for OMM, as it will enable us to further secure our position in the cable installation market, which is where we see much of our future work. Our ability to bring together equipment and project-specific vessels that are not just ‘off the shelf' and provide individual project-based solutions is one of our main strengths," he said.
The operations will include the post-lay burial of the HVAC cables, ensuring adequate burial depth has been achieved to provide satisfactory protection from potential third party subsea damage.
OMM will undertake a post-lay burial survey to ascertain that the required depth has achieved and conduct a second pass burial operation as needed before completing a final survey. Final reporting and charting, digital video and GIS deliverables will also be carried out.