The aim of this guide is to help develop a greater understanding of the components and processes involved in the development of UK offshore wind farms that will be built up to 2025.
More explanation of content is provided in Interactive guide.
To supplement what is in the guide in PDF format, we have added photographs and a range of other information relevant to the UK industry.
BVG Associates is grateful to the following companies for their help in compiling the PDF guide:
DEME Group, GE Renewable Energy, Fugro, Generating Better, Innogy, JDR Cable Systems, MHI Vestas Offshore Wind, Natural Power (Fred. Olsen), Oldbaum Services, Ørsted, Senvion, Siemens Gamesa Renewable Energy, Siemens Power Transmission and Distribution, SNC-Lavalin - Atkins, Vattenfall
Bird and marine mammal survey aircraft provide a platform for surveying to take place.
Resource and metocean assessment is carried out to provide atmospheric and oceanographic datasets to inform the engineering design of a wind farm, the potential future energy production, and to fully describe the likely operating conditions at the proposed wind farm location.
Sea bed surveys analyse the sub sea bed environment of the proposed wind farm site and export cable route to assess its geological condition and engineering characteristics. The data collected is utilised in a wide range of engineering and environmental studies through the design and development phase.
Resource and metocean assessment is carried out to provide atmospheric and oceanographic datasets to inform the engineering design of a wind farm, the potential future energy production, and to fully describe the likely operating conditions at the proposed wind farm location.
Weather forecasts are needed for short-term planning of offshore activities (for example vessel transfers andlifts) and the closer the forecast is to the activity, the more reliable it gets. Metocean data recordings are used to provide real time data to support offshore activity, to verify forecast tools and to resolve disputes regarding weather downtime. Key metocean parameters that impact installation and commissioning activities are wind speed, wave height and current.
The turbine installation vessel transports the turbine componentsto site and supports the erection of the turbine on the foundation. Similar jack-up vessels are used to those for foundation installation.
The foundation installation vessel transports the foundations from the quayside fabrication facility or construction port to the site and secures them to the sea bed. Heavy lift vessels, floating sheerleg vessels and self-propelled jack-up vessels are all used.
The installation of the offshore substation consists of the transfer of the substation from its quayside fabrication site and the installation on the foundation.
The primary function of a monopile is to support the static and dynamic loads of the wind turbine through anchoring it firmly to the sea bed using the embedded part of the monopile.
The cable-laying vessel lays the cables between the wind turbines and offshore substation and between the offshore and onshore substation.
A trenching ROV forms a trench in which to bury the cable. This tool is generally used in post-lay burial but can be used during simultaneous lay.
Weather forecasts are needed for short-term planning of offshore activities (for example vessel transfers andlifts) and the closer the forecast is to the activity, the more reliable it gets. Metocean data recordings are used to provide real time data to support offshore activity and to verify forecast tools.
Effective turbine maintenance and service ensures the long-term productivity of the turbines.
The turbine converts kinetic energy from the wind into three-phase AC electrical energy
SOVs provide an offshore OMS base, with staff working from the vessel for periods of two to four weeks at sea. SOVs are the preferred way to maintain and service wind farms located far from shore.
The primary function of a jacket is to support the static and dynamic loads of the wind turbine by anchoring it firmly to the sea bed using a set of pin piles.
CTVs provide access for technicians and contractors to the wind turbines from the onshore OMS base to turbine locations and substation. CTVs are the preferred access solution for projects closer to shore.
Ensures there is no interruption to transmission from electrical failures or structural problems with the offshore platform.
Decommissioning plans typically are required as part of gaining approval to construct. These may define specific requirements for removal of components below the mud line which in turn may drive the choice or design of substation foundations and installation methods.
Removal and shipment to shore or cut-off at sea bed level and making safe.
Bird and marine mammal survey aircraft provide a platform for surveying to take place.
Resource and metocean assessment is carried out to provide atmospheric and oceanographic datasets to inform the engineering design of a wind farm, the potential future energy production, and to fully describe the likely operating conditions at the proposed wind farm location.
Sea bed surveys analyse the sub sea bed environment of the proposed wind farm site and export cable route to assess its geological condition and engineering characteristics. The data collected is utilised in a wide range of engineering and environmental studies through the design and development phase.
Weather forecasts are needed for short-term planning of offshore activities (for example vessel transfers andlifts) and the closer the forecast is to the activity, the more reliable it gets. Metocean data recordings are used to provide real time data to support offshore activity, to verify forecast tools and to resolve disputes regarding weather downtime. Key metocean parameters that impact installation and commissioning activities are wind speed, wave height and current.
The turbine installation vessel transports the turbine componentsto site and supports the erection of the turbine on the foundation. Similar jack-up vessels are used to those for foundation installation.
The foundation installation vessel transports the foundations from the quayside fabrication facility or construction port to the site and secures them to the sea bed. Heavy lift vessels, floating sheerleg vessels and self-propelled jack-up vessels are all used.
The primary function of a jacket is to support the static and dynamic loads of the wind turbine by anchoring it firmly to the sea bed using a set of pin piles.
Offshore substations are used to reduce electrical losses before export of power to shore.
The installation of the offshore substation consists of the transfer of the substation from its quayside fabrication site and the installation on the foundation.
The array cable creates loops or individual strings connecting all wind turbines to the offshore substation.
The primary function of a monopile is to support the static and dynamic loads of the wind turbine through anchoring it firmly to the sea bed using the embedded part of the monopile.
The cable-laying vessel lays the cables between the wind turbines and offshore substation and between the offshore and onshore substation.
Effective turbine maintenance and service ensures the long-term productivity of the turbines.
The turbine converts kinetic energy from the wind into three-phase AC electrical energy
SOVs provide an offshore OMS base, with staff working from the vessel for periods of two to four weeks at sea. SOVs are the preferred way to maintain and service wind farms located far from shore.
CTVs provide access for technicians and contractors to the wind turbines from the onshore OMS base to turbine locations and substation. CTVs are the preferred access solution for projects closer to shore.
Foundation inspection and repair identifies and addresses corrosion and structural problems above and below the water line.
Ensures there is no interruption to transmission from electrical failures or structural problems with the offshore platform.
Main component refurbishment, replacement and repair consists of the replacement of large components such as gearboxes, blades, transformers and generators in a timely and cost effective manner.
Decommissioning plans typically are required as part of gaining approval to construct. These may define specific requirements for removal of components below the mud line which in turn may drive the choice or design of substation foundations and installation methods.
Removal and shipment to shore or cut-off at sea bed level and making safe.
Complete removal and shipment to shore of turbine rotor, nacelle and tower.