Canyon Offshore to Trench Hornsea One Inter-Array Cable Routes

Siem Offshore Contractors (SOC) has awarded Canyon Offshore Limited, an Aberdeen-based trenching solutions provider, a contract for the provision of trenching services on DONG Energy’s Hornsea Project One offshore wind farm.

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Canyon Offshore’s award will require the trenching of approximately 140km at the wind farm site for the inter-array grid cables that will be laid onto the seabed by Siem Offshore Contractors, which was contracted for the installation of the project’s inter-array grid cable system by DONG Energy in November 2016. SOC’s scope of work includes the installation of 81 submarine composite cables as well as the associated post-lay trenching works.

Canyon Offshore said it will use both jetting and cutting methodology with its Jet Trencher, T1200 and its hard ground trencher, i-Trencher. Both systems, together with two work class remotely operated vehicles, will be deployed from a single support vessel, the chartered Grand Canyon I.

Operations are scheduled to commence in the last quarter of 2018. Management of the operations will be provided from Canyon Offshore Limited’s Aberdeen base.

Duncan Clark, Hornsea Project One Director, said: “We are delighted that Siem Offshore Contractors have chosen to work with another UK based company, as a strong and competitive UK supply chain providing the specialist capabilities needed to serve this growing industry will ultimately help to reduce the cost of electricity.”

The Hornsea Project One offshore wind farm is located approximately 120km off the Yorkshire coast within the central North Sea sector, and will comprise 174 Siemens 7MW wind turbines, which will be interconnected by 33kV medium voltage alternating current submarine composite cables.

In 2016, DONG Energy awarded JDR and Nexans with contracts for the inter-array cables. JDR will deliver 242km of cables, covering two thirds of the total wind farm capacity. Nexans will supply and install 139km of cables, inter-linking a total of 58 wind turbines, and will also install the internal cabling of all three transformer stations for Hornsea Project One in their building yards.

On completion in 2020, Hornsea Project One will be the world’s first offshore wind farm to exceed 1,000MW in capacity.