Seaway7 has installed the first inter-array cable at Ørsted's Hornsea 3 offshore wind farm in the UK North Sea, marking the commencement of a significant cable installation campaign, MarineLink Maritime News reported on 13 November 2026.
The newly laid cable is the opening phase of what Seaway7 describes as a large-scale programme of intra-farm electrical infrastructure works. The company will transport and install more than 536 kilometres of 66 kilovolt inter-array cable as part of the contract for Hornsea 3, a 2.9 gigawatt project.
The cable installation marks a tangible progression of seabed works at Hornsea 3. Seaway7's campaign will deliver the interconnections required to gather generation across the wind farm array.
The work will be carried out in the UK sector of the North Sea, where Hornsea 3 is being developed. Ørsted remains the project's developer and owner as it advances toward completion of the generation and electrical collection systems.
The scale of the cabling requirement reflects Hornsea 3's capacity. At 2.9 gigawatts the project is one of the larger UK offshore wind farms and requires extensive internal electrical routing to collect and transmit power from individual turbines to the export system.
Scope of the cabling campaign
Seaway7 will move and lay in excess of 536 kilometres of 66kV inter-array cable for Hornsea 3. The figure supplied by MarineLink sets out the physical extent of the contractor's assignment within the wind farm's wider balance of plant works.
The inter-array cables specified are rated at 66 kilovolts, the voltage level noted for the internal electrical network within the wind farm. The installation of the first cable represents the start of that multi-hundred-kilometre operation.
Project context
Hornsea 3 is identified as a 2.9GW development off the UK coast in the North Sea. The campaign of cable works is one discrete element of the overall project delivery process for Ørsted's scheme.
Seaway7's contract for cable transport and installation forms part of the necessary steps to assemble the wind farm's internal electrical architecture ahead of final commissioning.
MarineLink's report places the first cable installation on 13 November 2026 and frames it as the beginning of the main cable campaign by Seaway7. The company will continue to mobilise resources to fulfil the stated scope of work.
The arrival of the first inter-array cable on the project is likely to be followed by a sustained period of laying and testing across the wind farm's planned cable routes. The delivered length cited indicates the logistical scale of the operation for the contractor.
Further milestones for Hornsea 3 will depend on the completion of the inter-array network alongside other construction and commissioning activities. The timing and sequencing of those activities were not detailed in the MarineLink account.
The installation of the first inter-array cable at Hornsea 3 therefore represents a clear development on site and the opening of a major phase in the wind farm's electrical works, as reported by MarineLink on 13 November 2026.