Asso.subsea Secures Nearshore Cable Installation Scope

29 July 2025

(Image credit: Asso.subsea)

Asso.subsea has been awarded the nearshore cable installation scope for three key projects under TenneT’s 2 GW Program: BalWin4, LanWin1, and LanWin5. These projects are located off the northwestern coast of Baltrum Island, in northern Germany, and mark the beginning of a new collaboration with Jan De Nul, acting as the main contractor, with TenneT as the end client.

Each project involves the transportation and nearshore installation of a complex cable bundle comprising 2x HVDC power cables, 1x metallic return cable, and 1x fiber optic cable. Installation will be executed in 2027 (BalWin4), 2028 (LanWin1), and 2029 (LanWin5), respectively.

The scope of work includes:

Cable transpooling from load-out ports in the Netherlands or Germany
Nearshore installation operations using the CLV Atalanti, which will be specially modified to accommodate the 4-cable bundle configuration.
Precision cable landing via beaching operations with spud cans
Cable free-lay in intertidal zones and wet storage of cable ends
These nearshore operations are highly sensitive to tidal conditions, requiring detailed planning and precise execution. Our in-house capabilities, vessel adaptability, and commitment to engineered solutions ensure that we’re ready to meet the unique demands of these technically challenging works.

This award underscores Asso.subsea’s continued role in Europe’s offshore energy expansion and highlights our evolving partnership network as we continue to support the energy transition.