D.1 Floating offshore wind turbine decommissioning


Disconnection of floating offshore wind turbine from moorings and cables at the wind farm site and tow back-to-port. It includes disassembly into smaller assemblies or components for reuse, recycling, or disposal.

What it costs

About £3 million for a 450 MW floating offshore wind farm.

Who supplies them

Expected to be the same as the floating offshore wind turbine installers.

Key facts

The floating offshore wind turbine decommissioning process is the reverse, at a high-level, of the installation process. The floating offshore wind turbine is disconnected from mooring lines and cables at the site. It is then towed back to the port using AHVs and smaller support vessels, for wind turbine and floating substructure disassembly.

Where it is determined that the remaining life is sufficient, there will be a market for reuse of second-hand components, either as spares or re-installation elsewhere, for example yaw motors or anemometers.

In general, the removal process will be quicker than for installation because minor damage to components will be less critical. If components are to be recycled rather than reused, then less care needs to be taken to preserve the delicate aerodynamic surfaces and the condition of components. This may enable the use of different equipment or operations in a wider range of operating conditions.

Guide to a Floating Offshore Wind Farm