Offshore Projects News Roundup | December 1 – Cable-lay and survey works in the Netherlands, Taiwanese wind farm installation works and more

Cable-laying activities are ongoing at two Dutch offshore wind farms while newly awarded contracts include those for turbine installation in Taiwan, site investigations in the Netherlands, and completion of a subsea connector link between Ireland and France.

Jan De Nul completes first phase of cable-lay works for TenneT

The Jan De Nul Group recently completed the first part of the cable installation works that will connect the Hollandse Kust Noord and West Alpha offshore wind farms to the Dutch mainland.

Under the same project, the 220kV high-voltage tests of both sea and land cables for Hollandse Kust Noord were successfully completed, from the onshore substation to the substation located 18 kilometres offshore.

The cable installation vessel Isaac Newton installed the cables on the seabed. In addition, Jan De Nul used several remote-controlled underwater trenchers and amphibious cranes in the surf zone to bury and protect the cable in the seabed.

The cables were manufactured in South Korea and transported to the site by Isaac Newton.

The cables connecting Hollandse Kust Noord to the mainland have been successfully installed, buried, and tested. The cables connecting Hollandse Kust West Apha will be installed in the spring of 2023.

In total, Jan De Nul is installing four sea cables in three installation campaigns. These sea cables will connect the transformer stations of the two wind farms to the mainland.

Each transformer station will receive two cables, altogether accounting for a total cable length of 235 kilometres.

Nexans secures work for subsea connector link between Irish and French grids

Nexans has been awarded the contract for the Celtic Interconnector developed jointly by the Irish and French transmission system operators EirGrid and Reseau de Transport d’Electricite (RTE).

This 700MW capacity project will deliver the first subsea link for direct electricity exchange between France and Ireland, supplying power for approximately 450,000 homes.

The interconnection between France and Ireland will use HVDC 320kV technology. It includes a 500-kilometre subsea cable route, a 40-kilometre underground route in Brittany, and a 35-kilometre underground route in Cork County.

The 400kV HVAC 10km connection to the Irish grid is also part of the project awarded to Nexans.

DEME, CSBC Corporation awarded transport and installation contract in support of Taiwan’s Hai Long wind farm

CSBC-DEME Wind engineering (CDWE), a joint venture between DEME and Taiwanese shipbuilder CSBC Corporation, has been selected to execute the transport and installation of the foundations, turbines, and offshore substation at the Hai Long offshore wind farm in Taiwanese waters.

A total of 73 wind turbines generating a combined 1,044 MW will be installed. Pre-piling works are scheduled to start in 2024.

CDWE will utilise the installation vessel Green Jade, which will be equipped with a DP3 system and a 4,000-tonne heavy duty crane.

Fugro tapped for two Dutch offshore wind site investigations

Fugro has been awarded two geotechnical investigation contracts for the development of the Dutch IJmuiden Ver Site V-VI, Nederwiek (zuid) Site I and Hollandse Kust (west) Site VIII offshore wind zones.

The comprehensive data gathered will be used by windfarm developers as input for preliminary engineering design studies and future tenders, and will also be available for power cable design, archaeology and marine biology investigations.

Specialist geotechnical vessels from the Fugro fleet will commence the surveys in March 2023 and continue into the fourth quarter of 2023. The company said further processing, laboratory testing and reporting of results will take well into 2024.