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Successful Replacement of parts of the Anholt Export cable

JD-Contractor successfully replaced two sections of the Anholt Export cable. The two sections were the shore end section including shore end landing operation and the section at the platform including pull up on the platform. The work was carried out during difficult weather conditions with focus on minimizing power distribution loss.
In February, there was a fault in the submarine cable that connects the Anholt offshore wind farm to the grid on land. The error was corrected with assistance of JD-Contractor, and after four weeks of outage the turbines could again provide power through the cable.
Since then, Energinet.dk in cooperation with the supplier of the cable (NKT Cables) and with the help of an external test laboratory analyzed the error on the cable. The results indicate that there is a risk of cable faults in the first 400 meters of the submarine cable from Grenå and the last 4 km before the substation due to non-conformities in production of the cable.
To minimize the risk of breakdowns, Energinet.dk decided to replace the parts of the submarine cable, were analyzes indicated there was a risk that faults may occur. Energinet.dk contracted JD-Contractor A/S to assist with replacement of two sections of the Anholt Export cable from.
The work included pre-tenching of approx. 4.4 km trenches, two pull-in/pull-up operations, laying of two cable sections, recovery of 4.4 km. scrap cable and insertion of two offshore joints. The work was very dependent on the weather and estimated to last 5-6 weeks. However, despite several periods with bad weather the work was completed within schedule. As a result of a strong focus on minimizing power distribution loss, the downtime on the Anholt Offshore Windfarm was limited to the period between 26th of October and 23rd of November - less than four weeks.
The scope of work was successfully completed in accordance with the developed RAMS, resulting in a fast and efficient cable repair operation with focus on minimizing power distribution loss and costs for Energinet.dk, as well as high focus on safety during the operations.
Good cooperation between Energinet.dk, JD-Contractor, nkt cables and the MWS proofed to be a successfully combination for the completion of the cable repair operation in record time.