Floating turbines have the same upper structure as bottom-fixed turbines. Instead of sitting on a fixed structure, the turbine is attached to a ‘floater’ – a movable structure that provides the turbine with buoyancy and stability, to keep it upright at all times. This floater is secured to the seabed using mooring lines and anchors.
In comparison, bottom-fixed designs are generally built directly on, or into, the seabed, using either a steel or concrete monopile or a legged ‘jacket’ which resembles a huge 3- or 4-legged stool attached to the seabed. The turbine and its tower sit on top of this monopile or jacket.