Cerulean chooses vessel provider for gigawatt Scottish floating wind farm as attention turns to turbines

Cerulean Winds has selected marine construction and operations contractor Ocean Installer as it puts together the pieces for the future development of the 1GW Aspen floating offshore wind farms in Scotland.

The London-headquartered company has set about choosing its preferred suppliers for an "alliance" of companies intended to reproduce the EPCI contractual model widely used in the oil and gas sector.

“Ocean Installer’s addition to the alliance is vital to driving down cost of installation, a critical component within (floating offshore wind) FLOW development,” Cerulean stated in its announcement.

“The company’s existing fleet of vessels and a highly skilled workforce, developed over decades working in subsea oil and gas construction, can be transferred to the FLOW sector without significant adaptation”.

Cerulean has already entered into a preferred vendor arrangement with Haventus, owners of the Port of Ardersier, on dry storage of the structures, batched installation and quick connect/disconnect systems.

Assuming a final investment decision is reached, Cerulean said Ocean Installer will provide proven engineering expertise and installation services for the mooring system installation, inter-array cables system and marshalling of the floating units during the fabrication phase, tow-out and hook up.

“For FLOW to be successful in the North Sea we’ve got to use expertise and experience from the oil and gas sector to turbo-charge the speed of cost reduction – that is what Ocean Installer are bringing to our project,” said Dan Jackson, founding director of Cerulean Winds.

“Using OI’s capabilities, we believe we can develop a standardised process to cut installation costs and make FLOW’s Levelized Cost of Energy (LCOE) comparable to fixed offshore wind.”

The offshore contractor’s track record includes a history of supporting floating oil and gas developments, including dynamic flexible product procurement and mooring system installation, Cerulean noted.

Up to 6GW

The 1GW Aspen site is one of three wind farm leases acquired under Crown Estate Scotland’s Innovation and Targeted Oil & Gas (INTOG) leasing round in 2023.

While all three sites were chosen for their proximity to oil and gas producing assets, development plans show Aspen advancing first with an early development phase targeted for 2028/29 and full commercial operation in 2030.

Under the INTOG framework, each of the three areas was nominated with 1GW of capacity, geared toward decarbonising offshore oil and gas production but Cerulean has since advanced plans for potentially doubling capacity on all three areas. This would be achieved by making adjustments in turbine capacity and the density of distribution.

If Aspen and the areas known as Beech and Cedar are all fully developed, up to 300 turbines could be deployed, according to the developer.

Decision time

Offshore surveys for the planned Aspen floating offshore wind farm were concluded in January, when the developer stated that it was on course to take FID in 2026.

Other preferred supplier agreements already signed by Cerulean include the selection of NOV for floating foundations, using the US engineering company's semi-submersible design.

Siemens Energy has been selected for electrical transmission and Worley will be systems engineer and interface manager.

Cerulean has also selected industrial contractor Bilfinger as its preferred choice to provide operations and maintenance (O&M) service for the future development.