The aim of this guide is to help companies develop a greater understanding of the components and processes involved in the development of floating offshore wind farms in the UK.

The floating offshore wind industry is early in its development, with only a small number of pre-commercial projects installed globally. It is expected to grow significantly, with between 6 and 10 GW of capacity operational by the end of 2030.

There are many challenges still to address, including:

  • Development: how to mitigate the impact of floating offshore wind farms on the sea bed and other marine users, as the impact is different from fixed offshore wind farms
  • Design: how to accelerate the feedback loop between designing, testing and learning, especially for the floating substructure, mooring system and dynamic cable system, and establish design standards optimised for floating offshore wind
  • Manufacture: how to achieve economies of simplification, standardisation and scale, given the current industry maturity
  • Offshore operations: how to establish new, efficient and effective ways of working for offshore installation, operations and maintenance (O&M), as there are significant differences from fixed offshore wind farms, and
  • Financing: how to give confidence to investors, lenders and insurers regarding performance and level of risk to reduce the financing costs of projects.

The example from fixed offshore wind is that significant progress across similar challenges has been successfully achieved and there is no reason to doubt that the floating offshore wind industry will address its challenges too.

To keep things simple, this guide uses a single reference design of floating substructure to provide a narrative that can be followed easily. This is a three-column, steel, semi-submersible substructure. It is selected because it has already been demonstrated at two pre-commercial floating offshore wind farms and could be used widely elsewhere. It was not selected to represent the best future solution.

The guide also uses a set of reference parameters to ground some of the narrative and the cost estimates. These include turbine rating, wind farm rating, final investment decision (FID) date and commercial operations date. These are fully described in Floating technology.

Where relevant, for each element in the wind farm we cover:

  • Function. What the component or service does
  • What it costs. We provide typical prices for a project with parameters described in further sections. We recognise that there can be a range in prices of any element, due to specific timing or local issues, exchange rates, competition and contracting conditions. Prices for large components include delivery to nearest port to supplier and warranty costs. Developer costs (including internal project- and construction management, insurance, typically spent contingency and overheads) are included in the highest-level boxes but are not itemised. The sum of costs in lower-level boxes therefore is often lower than in the highest-level box. Costs, when combined with project life of 25 to 30 years, capacity factor of just over 50% and weighted average cost of capital equate to the bid prices bid prices expected by developers of floating projects.
  • Who supplies them (examples only). The list of suppliers is indicative rather than exhaustive. We have focused on suppliers with proven capability and generally have not listed suppliers with likely future capability or located distant from the UK (for example in US or China). Nevertheless any omission does not reflect any judgement of a company‚Äôs capabilities.
  • Key facts. Description including dimensions / materials where relevant or what is involved in delivering the service / how it relates to other elements and other relevant information.
  • What’s in it. We list the sub-components / services described elsewhere in the guide, or standard components / materials / processes used across a range of industries.

A glossary is provided, recognising that there are many industry-specific or technical terms and abbreviations used in the descriptions.

Guide to a Floating Offshore Wind Farm