Front-end engineering and design (FEED) studies address areas of floating offshore wind farm system design and develop the concept of the floating offshore wind farm in advance of procurement, contracting and construction.

What it costs

About £4 million for a 450 MW floating offshore wind farm.

Who supplies them

Arup, DNV, Gavin & Doherty Geosolutions, Kent, Mott MacDonald, ODE, OWC, Ramboll, Wood and Worley.

Key facts

Earlier on in the process, concept and pre-FEED studies are used to develop an outline concept of the project for the purposes for defining the consent envelope and to inform environmental surveys.

The FEED study is continually refined through the development process and is ultimately used to inform substantial engineering and procurement decisions.

Key parameters such as turbine size, substructure type, mooring system design, wind farm layout, substation design, electrical system, and grid connection are considered in order to minimise project LCOE. Some projects consider integrating floating offshore wind turbines with co-located batteries, green hydrogen generation or the powering of oil and gas production facilities.

FEED studies also include the planning of onshore and offshore operations, port and vessel strategies, determining contracting methodologies and the development of key risk management and health and safety procedures.

The FEED study seeks to understand the total wind farm system in an integrated way and to consider the impact of engineering decisions on the LCOE, and to ensure that engineering decisions take full cognisance of environmental and consenting risks and impacts.

The FEED study is a multi-disciplinary process that requires extensive communication and coordination, often across multiple teams and organisations.

Engineers normally use industry-specific standards to guide the design process for components including, but not limited to, the floating substructure. The most complete standards for floating offshore wind are IEC 61400‐3‐2 and DNV‐ST‐0119. Other standards used on current floating offshore wind projects include ABS 195/206, NKRE-GL-FOWT01 and BV NI572.

The outputs of FEED studies are used to procure and construct the floating offshore wind farm.

The move to auction-based systems such as CfD in the UK has placed a greater emphasis on FEED studies as developers require greater cost certainty earlier in the development process.

Developers of early floating offshore wind projects are likely to conduct more detailed FEED studies, and hence incur higher FEED costs, because floating offshore wind project norms have not yet been established. The detail and cost of FEED studies will decrease as developers gain more experience and designs and operational practices become more established.

Project certification is an independent process used to give confidence to parties such as the developer’s senior management, lenders or insurers, that the design, manufacture and installation of the whole project has been carried out to appropriate standards. It is not a regulatory requirement in the UK but is normally used for offshore wind projects. Certification schemes applicable to floating offshore wind include IECRE OD‐502, DNV‐SE‐0190 and DNV‐SE‐0422.

What’s in it

Guide to a Floating Offshore Wind Farm