Dutch and German transmission system operator TenneT has signed an agreement with Jan De Nul Group to conduct repairs for high voltage offshore cables in the German Bright.

Jan De Nul

Image: Jan De Nul to provide offshore cable repairs for TenneT. Photo: Courtesy of Jan De Nul Group.

In the event of faults or failures to the high-voltage cable system, Jan De Nul will mobilize within the contractual period with the European electricity transmission system operator. Currently, the contract is for 24 months, with two optional extensions of 12 months each.

As per the contract, Jan De Nul will conduct repairs to all of TenneT’s existing HVAC cable systems that connect individual wind farms to the offshore convertor stations or directly to the onshore grid, along with repairs of all its HVDC cable systems connecting the offshore convertor stations to the onshore grid.

The scope of the contract will also include future connections commissioned within the duration of the agreement.

To fulfill this contract, Jan De Nul stated that it will deploy its cable laying vessels Isaac Newton and Willem de Vlamingh. It also claims that preparatory engineering works required to perform the cable repairs have already been started. If a HV cable fails, Jan De Nul will immediately deploy one of its offshore cable laying vessels.

Jan De Nul Group offshore cables manager Wouter Vermeersch said: “We are delighted for Jan De Nul Group to be selected as the cable repair contractor for TenneT’s HV cable system. This agreement continues our trusted relationship with TenneT and furthers Jan De Nul’s position as a reliable and experienced cable installation contractor.”

The company stated that last year, its Willem de Vlamingh had installed cables to connect the Trianel Windpark Borkum and Borkum Riffgrund II wind farms to TenneT’s DolWin Gamma and Alpha offshore convertor stations. These cables will also be covered under the present agreement.

Jan De Nul claims that it has executed several cable installation projects in Belgium, the UK, Germany, Iceland, Egypt, Canada, Mexico, Russia, Taiwan and in the Middle East. In 2017, the company carried out the cable joints for an urgent cable repair in Iceland by means of the Isaac Newton.