Extended Operational and Trade Vocabulary

Offshore Wind Installation and Cable Lay glossary

The offshore-wind installation vocabulary: jack-up installation vessels (Aeolus), AC export cables, transition-piece access platforms, the installation contractors and named vessels, and the monopile and turbine-erection terms. Grounds each term in the installation campaign or the cable-lay operation it belongs to.

632 defined terms.

Showing 250 on this page (page 1 of 3).

A

A2SEA: Former Danish offshore wind installation contractor whose fleet, including Sea Installer and Sea Challenger, was acquired by DEME Offshore in 2017.
Aberdeen Bay: Site of the European Offshore Wind Deployment Centre operated by Vattenfall off the Scottish coast.
AC export cable: High-voltage alternating current submarine cable used to transmit offshore wind power to shore over moderate distances.
Access platform: Secondary steel structure welded to the transition piece allowing crew transfer vessel boat landing access.
Aeolus: Jack-up installation vessel owned by Van Oord, used widely for monopile and turbine installation across European offshore wind farms.
Aibel: Norwegian topside fabricator that has delivered HVDC converter platforms for Dogger Bank and DolWin projects.
Air gap: Vertical distance from the fuel surface to the top of the tank, used in ullage measurement.
Airborne Lidar: Laser scanning from aircraft used in coastal topography.
Allision: contact between a moving vessel and a fixed object such as a wharf or bridge.
Alpha Ventus: First German commercial offshore wind farm, commissioned in the North Sea in 2010.
Aluminum sacrificial anode: Block of aluminum alloy bolted to monopiles and jackets to provide galvanic corrosion protection.
Anchor handling tug supply: Vessel class used to position spread moorings for cable-lay barges and floating accommodation units.
Anchor Pattern: Geometric layout of mooring legs around a moored unit.
Anode cage: Steel framework securing sacrificial anodes around the splash zone of a monopile foundation.
Apollo: Heavy lift jack-up vessel operated by Maersk Supply Service, contracted on US East Coast offshore wind work including Empire Wind.
Approach corridor: Designated marine traffic lane preserved through an offshore wind lease area to maintain navigational safety.
Aqua Ventus: Floating offshore wind demonstration project off Maine developed by the University of Maine consortium.
Aquaterra: Geotechnical and geophysical site investigation contractor active in offshore wind pre-FEED studies.
Aramis: Dutch offshore CO2 transport and storage project sharing North Sea seabed corridors with offshore wind cable routes.
Aran Islands: Reference geographic marker for proposed Irish offshore wind lease areas in the Atlantic.
Archimedes screw: Not used in offshore wind; term retained here to distinguish from helical pile installation methods.
Area development plan: Comprehensive site layout document submitted to a regulator covering turbine positions, cable routes, and offshore substation siting.
Argyll Array: Cancelled ScottishPower Renewables offshore wind project once proposed off Tiree.
Arklow Bank: Irish Sea offshore wind farm, the first commercial offshore wind project in Ireland.
Armor wire: Helical layer of galvanized steel wires providing tensile strength and mechanical protection to submarine power cables.
Array cable: Inter-array submarine cable connecting wind turbine generators to the offshore substation.
Articulated boat landing: Hinged ladder and fender arrangement on transition pieces that pivots to absorb crew transfer vessel impact.
As built drawing: Final fabrication or installation drawing reflecting the actual configuration following any deviations from design.
Atlantic Shores: US offshore wind lease area off New Jersey developed by Shell and EDF Renewables.
Auction: Competitive tender process used by Crown Estate, BOEM, and European regulators to award offshore wind seabed rights.
Avangrid: US renewable energy developer, partner with Copenhagen Infrastructure Partners on Vineyard Wind 1.
Avedore: Danish port site for offshore wind component logistics adjacent to Copenhagen.
Average annual energy production: Long term mean electricity output of a wind farm used in financial modeling.
Azimuth Thruster: Propulsion unit rotating 360 degrees about a vertical axis to direct thrust in any horizontal direction.

B

Backfill: Granular or rock material placed in a trench above a buried subsea cable to restore the seabed profile.
Ballast pump: Centrifugal or self priming pump moving ballast water, increasingly replaced by submersible types.
Ballast water management: Regulatory regime under the IMO BWM Convention applicable to offshore wind support vessels.
Balsa core: Lightweight wood core material historically used in early onshore turbine blade construction.
Bare conductor: Uninsulated copper or aluminum conductor used in onshore overhead lines connecting onshore substations to the grid.
Barge mounted floating wind: Concept floating wind foundation using a shallow draft barge hull such as the Ideol Damping Pool design.
Bathymetry: Measurement and mapping of seafloor depth.
BCTC: Boskalis cable trenching contractor unit specializing in mass flow excavation.
Beach manhole: Onshore termination chamber where the submarine cable joints to the land cable system at the landfall.
Beatrice: Scottish offshore wind farm in the Moray Firth developed by SSE Renewables, Copenhagen Infrastructure Partners, and Red Rock Power.
Belgian North Sea: Concession zone hosting projects including Northwind, Belwind, Nobelwind, Mermaid, and SeaMade.
Belwind: Belgian offshore wind farm developed by Parkwind off the Bligh Bank.
Bend Stiffener: Tapered polyurethane structure at the top of flexible flowlines and umbilicals that controls dynamic curvature at the hangoff.
Bending radius: Minimum permissible curvature of a submarine cable during manufacture, loadout, lay, and operation.
Berth pocket: dredged area immediately alongside a berth.
Bibby Wavemaster: Service operation vessel class operated by Bibby Marine for offshore wind maintenance.
BiFab: Burntisland Fabrications, Scottish fabrication yard previously involved in offshore wind jacket fabrication.
Billia Croo: EMEC wave energy test berth near Orkney, sharing logistics with floating wind trials.
Birds directive: EU directive (2009/147/EC) influencing offshore wind consenting through avian impact assessments.
Bladt Industries: Danish steel fabricator producing transition pieces, jackets, and offshore substations for North Sea wind farms.
Block Island: First US offshore wind farm, a 30 MW jacket-founded project off Rhode Island commissioned in 2016 by Deepwater Wind.
Blue Economy: Sustainable use of ocean resources for economic growth.
Blue Tern: Cadeler X-class wind turbine installation vessel, originally part of the Swire Blue Ocean fleet.
BOEM: US Bureau of Ocean Energy Management; offshore leasing and resource evaluation.
Bokalift 1: Boskalis heavy lift crane vessel, a converted bulk carrier with a 3,000 t Huisman crane used for foundation and offshore substation installation.
Bokalift 2: Boskalis heavy lift crane vessel with a 4,000 t Huisman crane delivered in 2021 for offshore wind work.
Bold Tern: Cadeler wind turbine installation jack-up vessel, originally a Fred Olsen Windcarrier asset.
Bonded joint: Submarine cable joint where outer sheath, armor, and insulation are continuously rebuilt to match the cable cross section.
Boom rest: Cradle on a heavy lift vessel that supports the crane boom when stowed for transit.
Borssele: Dutch offshore wind zone containing Borssele I and II (Orsted), III and IV (Blauwwind consortium), and V (innovation site).
Boskalis: Dutch dredging and salvage major, parent of SMIT Salvage since 2010.
Boulder clearance: Pre-lay survey and removal of seabed boulders along cable routes using grabs or plows.
Bow loading: Cable lay operation with the cable departing over a bow chute, used on certain converted vessels.
BP: Oil and gas major holding offshore wind lease interests including Mona, Morgan, and Beacon Wind with Equinor.
Brave Tern: Cadeler wind turbine installation jack-up vessel, formerly of Fred Olsen Windcarrier.
Bridle: Two-leg rope or chain attached to a single point.
Brownsville: Texas Gulf port hosting US ship recycling facilities including ESCO Marine and International Shipbreaking Limited.
BSH: German Federal Maritime and Hydrographic Agency responsible for offshore wind permitting in the German EEZ.
Bubble curtain: Compressed air curtain deployed around pile driving operations to attenuate underwater noise for marine mammals.
Buoyancy module: Distributed flotation collar attached to dynamic cables in a lazy wave or steep wave configuration.
Burial assessment study: Engineering analysis determining target burial depth for subsea cables based on seabed risk.
Burial protection index: Mobility index used to size required cable burial depth against seabed scour and anchor drag.
Bus bar: Conductive bar within an offshore substation collecting and distributing power between cable feeders.
BVG Associates: UK consultancy publishing offshore wind cost benchmarking and supply chain studies.

C

Cable Enterprise: Prysmian cable lay vessel used for subsea power cable installation in European waters.
Cable factory acceptance test: Test sequence at the cable manufacturing plant verifying electrical and mechanical performance before shipment.
Cable Innovator: Global Marine cable repair and installation vessel with a long service record on submarine telecommunications and power cables.
Cable laying vessel: Specialized ship equipped with carousels, tensioners, and a stern or bow lay chute for installing submarine cables.
Cable pull-in: Operation of pulling a submarine cable into a J-tube or I-tube within a foundation or substation.
Cable repair joint: Field joint installed on a cable lay vessel to splice a repaired section into a damaged subsea cable.
Cable transition joint: Joint between a submarine export cable and an underground onshore cable at the landfall transition pit.
Cadeler: Danish offshore wind installation contractor formed from the demerger of Swire Blue Ocean, operating the Wind Orca, Wind Osprey, Bold Tern, Brave Tern, and Blue Tern.
Caisson: Large concrete box used in quay walls and dry docks.
California Floating: BOEM lease areas off Humboldt and Morro Bay designated for floating offshore wind development.
Capacity factor: Ratio of actual annual energy production to the maximum possible if a turbine operated at rated power continuously.
Cape Holland: Dutch supplier of vibratory hammers and gripper frames used for monopile pre-piling and installation.
Cape Wind: Cancelled Massachusetts offshore wind project off Nantucket Sound that did not reach construction.
Capital dredging: initial dredging to deepen or widen a channel or berth.
Carbon steel: Primary material for monopile, transition piece, and jacket fabrication in offshore wind structures.
Carousel: Rotating storage table on cable/umbilical lay vessels.
Catenary: sag of a mooring line or shore-power cable between supports.
Cathodic Protection: Sacrificial or impressed current system protecting subsea steel from corrosion.
CDWE: Compañía De Wind, an offshore wind installation joint venture; placeholder excluded; see CDWE entry below.
CDWE Green Jade: Heavy lift installation vessel jointly operated by CSBC and DEME for Taiwan offshore wind projects.
Centerline: Fore-and-aft line dividing the ship into port and starboard halves.
Centrica: UK energy company that previously held stakes in Race Bank and Lincs offshore wind farms.
Charybdis: First Jones Act compliant US-flag wind turbine installation vessel, built by Keppel AmFELS for Dominion Energy.
Cherry picker: Aerial work platform used onshore at the marshaling port for blade root and hub inspection.
China State Shipbuilding Corporation: State-owned shipbuilder, parent of CSSC Haizhuang offshore wind turbine business.
Choctaw I: Jones Act compliant offshore wind feeder vessel newbuild ordered by Crowley.
CHPP: Cable Hang Off and Pull-in Procedure, the document governing cable pull operations at offshore substations.
Class Notation: Class society designation reflecting compliance with construction and equipment rules incorporated into SOLAS by reference.
Coastal Virginia Offshore Wind: Dominion Energy commercial offshore wind project off Virginia Beach, building on the CVOW pilot.
Cofferdam: Temporary watertight enclosure for construction.
Coflexip Stena Offshore: Historical antecedent of TechnipFMC active in early flexible pipe and cable lay.
Cold Ironing: Onshore power supply enabling ships to shut down engines in port.
Collection substation: Offshore substation gathering array cable circuits and stepping up voltage for export.
Combined heat and power: Onshore reference technology; mentioned to contrast electricity-only offshore wind output.
Commissioning: Sequence of mechanical completion, energization, and performance testing before commercial operation.
Composite blade: Glass and carbon fiber reinforced polymer wind turbine blade, principal product of LM Wind Power and TPI Composites.
Concrete gravity base: Foundation type relying on submerged weight, used at Thornton Bank Phase 1 and elsewhere.
Conductor screen: Semiconducting layer over the conductor smoothing the electric field within high voltage cable insulation.
Connector strain relief: Mechanical termination preventing axial load from reaching the conductor inside cable joints.
Consents: Permits and approvals required for construction and operation, including DCO in the UK and BOEM COP approval in the US.
Contracts for Difference: UK government revenue support scheme guaranteeing a strike price for low carbon generation including offshore wind.
Conversion: Modification of an existing vessel into an offshore wind installation, cable lay, or accommodation unit.
Converter platform: Offshore HVDC converter station such as DolWin or BorWin connecting offshore wind to the onshore grid.
CoP: Certificate of Proficiency, issued for STCW short courses and ratings.
Copenhagen Infrastructure Partners: Danish fund manager investing in offshore wind including Vineyard Wind 1 and Changfang Xidao.
Cordierite: Refractory ceramic; not applicable to offshore wind; included only as a disambiguation marker.
Coriolis flow meter: Mass flow instrument used on grout mixing skids during monopile and transition piece grouting.
Corrosion Allowance: Reduction in MSL for components exposed to seawater.
CPT: Carriage Paid To, Incoterm 2020.
Crane Barge: Self-propelled or towed pontoon carrying a heavy lift crane for wreck removal.
Crew Transfer Vessel: Small high speed catamaran transferring technicians from port to turbines during construction and O&M.
Crown Estate: UK seabed manager responsible for offshore wind leasing in English, Welsh, and Northern Ireland waters.
Crown Estate Scotland: Manager of Scottish seabed leasing including the ScotWind round.
Cruciform: Cross shaped scour protection layout occasionally used around individual monopiles.
CS Wind: South Korean wind tower fabricator with facilities in Vietnam, the UK, and Portugal serving offshore and onshore markets.
CSC Haizhuang: Chinese offshore wind turbine OEM, alternative spelling for CSSC Haizhuang.
CSSC Haizhuang: Offshore wind turbine manufacturer subsidiary of China State Shipbuilding Corporation.
CTV: Crew transfer vessel; small catamaran transferring wind technicians.
Cyclic loading: Repeated load actions on offshore wind structures from wind, wave, and operational moments considered in fatigue design.

D

DC link: Direct current bus in frequency converters used for shaft generators and pod drives.
DCO: Designated Casualty Officer in some flag administrations responsible for intervention.
Deck cargo: Cargo carried on the weather deck.
Deep water mooring: Mooring systems for floating wind platforms in water depths typically beyond 100 meters.
Deepwater Wind: US offshore wind developer behind Block Island, now part of Orsted US.
DEME: Belgian marine contractor with subsidiaries including DEME Offshore active in foundation and turbine installation.
Demonstrator: Small scale pre-commercial offshore wind project intended to validate technology such as Hywind Demo or WindFloat 1.
Design wave: Statistically derived extreme wave height used in structural design of offshore wind foundations.
Dia Yuan: Reference Chinese offshore wind installation jack-up vessel.
Diameter to thickness ratio: Key geometric parameter influencing monopile fatigue and buckling design.
Digger pile: Specialized pile used as a temporary template for jacket installation alignment.
Dock leveler: Quayside hydraulic ramp used to bridge crew transfer vessel deck height differences at small ports.
Dogger Bank: North Sea fishing ground and the site of the 1781 Anglo-Dutch naval engagement.
Dolphin (mooring): Isolated mooring or fender structure at marshaling ports protecting quay walls from installation vessel impact.
DolWin: Series of German HVDC offshore grid connection clusters in the North Sea.
Dominion Energy: US utility developing the Coastal Virginia Offshore Wind commercial project and owner of the Charybdis WTIV.
Donghae 1: South Korean floating offshore wind project planning area.
Drag Embedment Anchor: Traditional fluke anchor embedding by horizontal pull.
Drilled installation: Foundation installation method using reverse circulation drilling, applicable to hard or boulder rich seabeds.
Driveability study: Geotechnical and pile dynamic analysis predicting hammer blow count for monopile installation.
DTOC: Dudgeon Triton Knoll Offshore Cable; not applicable here; placeholder noting offshore cable corridor naming conventions.
Dudgeon: UK offshore wind farm off Norfolk owned by Equinor, Masdar, and Statkraft.
Duga: Historical Soviet radar; included only to disambiguate from offshore wind project naming.
Dynamic Cable: Submarine cable used on floating offshore structures designed to withstand cyclic loading from wave and current motion.
Dynamic Positioning: Computer-controlled thruster station keeping for salvage and dive vessels.
Dyneema sling: High modulus polyethylene synthetic sling used in lighter offshore wind rigging applications.

E

East Anglia ONE: Operational UK offshore wind project of ScottishPower Renewables off Suffolk.
East Anglia THREE: ScottishPower Renewables UK offshore wind project under construction in the East Anglia zone.
East Anglia TWO: ScottishPower Renewables UK offshore wind project in the East Anglia zone.
Eddystone: Geographic marker off Plymouth; reference for early UK Round 3 zone assessments.
EDF Renewables: French utility developer holding offshore wind interests in France, the UK, and the US.
EDPR: EDP Renovaveis, Portuguese renewable developer with offshore wind interests through Ocean Winds with Engie.
Eemshaven: Dutch port serving as offshore wind marshaling base for German and Dutch North Sea projects.
EEW SPC: German monopile fabricator at Rostock, supplier of XL monopiles for North Sea wind farms.
EIA: Environmental Impact Assessment, statutory study supporting offshore wind consent applications.
Eider duck: Sea bird species frequently considered in UK and Baltic offshore wind environmental assessments.
Electrical infrastructure: Combined system of array cables, offshore substation, export cables, and onshore substation.
Empire Wind: US offshore wind project off New York developed by Equinor.
Energinet: Danish transmission system operator and partner in submarine HVDC interconnectors including Kontek, Skagerrak, and COBRAcable.
Engie: French utility, partner with EDPR in the Ocean Winds offshore wind joint venture.
EPCI: EPC plus installation; common offshore contract type.
Equinor: Norwegian operator and partner in the Northern Lights CO2 storage project.
ERM: Engine Room Resource Management, the engineering counterpart to BRM.
ERTV: Emergency Towing Vessel, often required in marine coordination plans during installation campaigns.
Esbjerg: Danish North Sea port acting as a primary marshaling base for European offshore wind installation.
Esvagt: Danish vessel owner providing service operation vessels to offshore wind operators including Orsted and Siemens Gamesa.
Eversource: US utility, former co-developer of Revolution Wind, South Fork, and Sunrise Wind, since divested to Orsted and Global Infrastructure Partners.
Export Cable: High-voltage submarine cable carrying power from an offshore substation to the onshore grid connection point.
Extra high voltage: Voltage class above 245 kV applicable to many offshore wind export systems and HVDC links.

F

Fabricated jacket: Welded tubular steel frame foundation suited to deeper waters and used at projects such as Wikinger and Beatrice.
Fairlead: Fitting that leads a rope in the desired direction without chafe.
Far North Fiber: Proposed transarctic submarine cable connecting Europe, Asia, and North America via the Northwest Passage and Northern Sea Route.
Fatigue life: Number of cycles a structural detail can sustain before crack initiation, controlling offshore wind foundation design.
Faulkner formula: Empirical formula for plate buckling used in offshore steel design.
FEED: Front end engineering design phase preceding EPC.
Feeder vessel: Jones Act compliant US-flag vessel ferrying components from port to a foreign-flag installation vessel offshore.
Femern Belt: Tunnel project corridor crossing the Baltic and influencing certain Danish offshore wind cable routings.
Ferguson Marine: Scottish shipbuilder; not principally an offshore wind builder, noted for context.
Fiber optic cable: Communications conductor integrated within power cables or laid alongside for SCADA and protection signaling.
Field joint: Submarine cable joint made offshore aboard the lay vessel after cable repair or installation.
Final investment decision: Project sanction milestone authorizing capital expenditure for offshore wind construction.
Finite element analysis: Numerical structural analysis applied to monopiles, transition pieces, and jacket connections.
Floatel: Mobile offshore accommodation unit deployed during major installation or commissioning campaigns.
Floating Lidar: Buoy mounted lidar wind measurement device used in pre-construction wind resource assessment.
Floating spar: Cylindrical deep draft floating wind substructure stabilized by ballast, exemplified by Hywind Scotland.
Floating wind: Offshore wind technology deploying turbines on floating substructures in deep water.
Flotron: Reference brand of inflatable subsea lift bags; included for installation aids context.
FOC: Fiber Optic Cable, often co-laid with power cables.
Foundation: Substructure transferring loads from the wind turbine to the seabed, including monopile, jacket, gravity base, and floating types.
Foundation installation vessel: Heavy lift or jack-up unit dedicated to monopile and jacket installation.
Foundry: Casting facility producing nacelle main frames, hubs, and large bearing housings for offshore wind turbines.
FOWT: Floating Offshore Wind Turbine.
Fred Olsen Windcarrier: Former owner of Bold Tern, Brave Tern, and other jack-up vessels, since reorganized under Cadeler.
Free issue: Contracting arrangement where the developer supplies turbines or foundations to the installer at no cost.
Fukushima FORWARD: Japanese floating wind demonstration project off Fukushima Prefecture.

G

Gabion mattress: Wire mesh containment for stone used in onshore cable trenching and landfall protection.
Gantry crane: Rail-mounted gantry such as STS, RMG, or RTG.
Gas insulated switchgear: Compact medium and high voltage switchgear used inside offshore substations.
GE Vernova: Energy spin off of General Electric encompassing the GE wind turbine business including Haliade-X.
Gemini: Dutch offshore wind farm in the North Sea off Groningen developed by Northland Power, Siemens, Van Oord, and HVC.
Geometric mooring: Catenary mooring layout typical of semi-submersible floating wind platforms.
Geophysical survey: Offshore site investigation using sub-bottom profilers, magnetometers, side scan sonar, and multibeam echo sounders.
Geotechnical drilling: Site investigation method recovering soil samples for foundation design via CPT and borehole sampling.
Global Infrastructure Partners: US fund manager partner in US offshore wind projects including Sunrise Wind and Revolution Wind.
GoM: Gulf of Mexico offshore region.
Goodwin Sands: Sandbank off the Kent coast that has influenced English Channel offshore wind layout planning.
GRA Offshore: Reference Spanish marine contractor; included for completeness.
Gravity base foundation: Foundation type relying on submerged self weight, optionally ballasted, used at Lillgrund and Thornton Bank.
Greater Gabbard: UK offshore wind farm off Suffolk owned by SSE Renewables and RWE.
Greenlink: Ireland UK HVDC interconnector sharing seabed corridors with offshore wind cable routes.
Grid connection agreement: Contract between offshore wind developer and transmission operator setting connection terms.
Grout: Cementitious filler between deck and bulkhead tiles, required to remain intact under VSP Item 33.
Grouted connection: Earlier transition piece connection method later supplemented by bolted flanged connections after slippage incidents.
GuanXi: Reference Taiwanese offshore wind installation port at Taichung.
Gulf Wind I: BOEM Gulf of Mexico offshore wind lease area auctioned in 2023.
Gunfleet Sands: UK offshore wind farm off Clacton owned by Orsted and Marubeni.

H

Haliade-X: GE Vernova offshore wind turbine platform deployed at Dogger Bank A and Vineyard Wind 1.
Halifax Wind: Reference Canadian offshore wind early stage proposal.
Hammer: Hydraulic or vibratory pile driving device installing monopiles and jacket pin piles.
Hammer energy: Per blow kinetic energy of an offshore pile driving hammer, with the IHC S-2500 rated at 2,500 kJ.
HDD: Horizontal Directional Drilling, trenchless method bringing export cables ashore beneath beaches and dunes.
HDPE duct: High density polyethylene conduit installed through HDD bores receiving the pulled-through submarine cable.
Heave Compensator: System absorbing vessel heave between vessel and load.
Heerema: Dutch heavy lift contractor operating Thialf and Sleipnir, active in offshore wind foundation and substation installation.
Hellenic Cables: supplier of shore-power cabling used in cold-ironing installations.
Heritage Cape Wind: Withdrawn Massachusetts offshore wind project; included only as historical reference.
High voltage alternating current: Transmission technology used for most offshore wind export systems under approximately 100 km cable length.
High voltage direct current: Transmission technology used for long offshore wind export cable connections such as Dogger Bank and German North Sea clusters.
Hinge restraint: Mechanical feature limiting bending at the top of a dynamic cable hang off.
Hollandse Kust: Dutch offshore wind zones (Noord, Zuid, West) developed under successive Dutch zero subsidy tenders.
Hornsea Four: UK offshore wind project under development by Orsted, currently subject to commercial reassessment.
Hornsea One: 1.2 GW UK offshore wind farm in the southern North Sea operated by Orsted.
Hornsea Three: UK offshore wind project under development by Orsted in the southern North Sea.