Function

Buoyancy and ballast modules are required to maintain certain cable shapes in the water column to reduce cable fatigue from the movement of the substructure. An example is the “lazy wave”.

What it costs

About £2.5 million for a 450 MW floating offshore wind farm.

Who supplies them

Balmoral, CRP Subsea, DeepWater Buoyancy, SBT Energy and Tekmar.

Buoyancy modules stored on a vessel prior to installation.
Buoyancy modules stored on a vessel prior to installation. Image courtesy of Balmoral. All rights reserved.

Key facts

Buoyancy and ballast modules hold the dynamic cable in its designed shape, to reduce cable fatigue. Buoyancy modules are attached to points of the subsea cable to provide uplift, which reduces tension in the cables and maintains wave configurations. Ballast modules provide weight to points of the subsea cable for damping stability.

Buoyancy and ballast modules are both typically clamped to the outside of the cable during installation (see I.2. for further information).

What’s in it

Guide to a Floating Offshore Wind Farm