Norway's Aibel has won a contract to build two HVDC converter platforms for Ørsted's Hornsea 3 offshore wind farm in the UK. Dutch offshore installation firm Heerema Marine Contractors will transport and install the two units in the UK North Sea, once completed. Hitachi Energy will supply two HVDC Light converter systems.
The Hornsea 3 offshore wind farm will be capable of generating up to 2.852 GW of electricity, enough to meet the average daily needs of over 3 million UK households. With this capacity, the wind farm will be the world's single biggest offshore wind farm.
Hornsea 3 will be located in the North Sea, approximately 120 km off the Norfolk coast and 160 km off the Yorkshire coast. The project will include up to 231 offshore wind turbines.
The contract for the construction and installation come following the Hornsea 3 wind farm developer Ørsted being allocated a Contract for Difference on July 7, 2022.
Aibel is responsible for engineering, procurement, construction, and installation in the delivery of two HVDC converter platforms. Hornsea 3 is Ørsted’s third project in the Hornsea Zone, where Hornsea 1 is operational, and Hornsea 2 currently is nearing operation. Heerema previously completed the installation of Ørsted’s Hornsea 2 offshore substations in 2021.
According to Aibel, the two platforms, Hornsea 3 Link 1 and 2, will have a lean design, with a steel jacket structure. The unmanned platforms will be operated from shore and accessed for maintenance by SOV (Service Operations Vessel) or helicopter.
The two platforms will have a combined capacity of up to 2.852 GW to serve the offshore wind turbines in the Hornsea 3 project.
Aibel’s currently has four platforms under construction – one for the Dolwin 5 project off the German coast, and three platforms for the Dogger Bank offshore wind farm in the UK part of the North Sea.
"With this latest addition to Aibel’s offshore wind portfolio, green energy projects make up a substantial part of the company’s order backlog," Aibel said.
“With the award of Hornsea 3, we accelerate our transformation towards renewables and low carbon solutions. Our order backlog now holds approx. 60% related to offshore wind and electrification of energy infrastructure. We are of course excited about this, and we look forward to work with Ørsted and deliver on our lean HVDC concept,” says Aibel’s President and CEO, Mads Andersen.
The construction of the two platform topsides will take place at Aibel's yard in Thailand. They will then be transported to Haugesund, where they will be outfitted with Hitachi Energy's latest generation HVDC converter valve technology prior to final completion and commissioning.
The platform topside for the Hornsea 3 Link 1 is scheduled to arrive in Haugesund in Q1 of 2025. Forecast sailaway to the Hornsea field is in 2026.
Aibel said that each platform represented a major contract for the company. Aibel uses the term "major" on contracts where the value of Aibel is over NOK 2.5 billion ($244,3 million).
Offshore Installation
For Heerema Marine Contractors, the work, of an undisclosed value, will include transporting and installing the two OCS jackets, eight skirt piles, and the two OCS topsides. Heerema will perform offshore lifting of the jackets onto the seabed before installing the piles to ensure fixation to the seabed. After executing the jacket installation, the OCS will be completed by installing the topsides onto the jackets. The company did not say which crane vessel it would use for the operation.
Heerema’s Chief Commercial Officer, Jeroen van Oosten: "We are very pleased to be awarded this contract by Aibel for the Hornsea 3 project. We have established a good working relationship throughout various successful projects together, which we will now extend to the transport and installation of these two substations."