Westermost Rough
Located 8km NE of Withernsea off Holderness coast, Yorkshire. Pioneered Siemens 6MW offshore turbine.
Status
Operationallifecycle stage
Ownership
Location
United KingdomNorth Sea
Technology
Capacity
210 MW ◆
Turbines
35 × 6 MW ◆
Model
Siemens Swt 6-0-154 ◆
Foundation
Monopile ◆
Site & conditions
Site rights
Seabed rights held ∴
Origination
Crown Estate Round 2 · 2003 ·
Water depth
15–15 m ◆
Distance from shore
8 km ◆
Wind speed
9.5 m/s @ 100 m ≈
Revenue & grid
Offtake
Other ◆
Grid
Secured · 2015 ◆
Connection
Hedon substation, Yorkshire (275kV) ◆
Schedule
FID
Jan 2013 ◆
COD
Jul 2015 ◆
Project timeline & ownership verified milestones on the spine · ownership from Hafrok’s transactions record
Origination · 2003-12
Crown Estate Round 2
- Awarded to
- Ørsted
- Basis
- seabed award
From the auction results — the round that created the project.
Farmdown · 2014-03
Ørsted → Marubeni / Green Investment Group 50%
- Stake
- 50%
- Consideration
- €281m
- Implied 100% value
- €563m
- Implied
- €2.68m / MW
- Announced
- 2014-03
- Closed
- 2014-Q3
- Project stage
- under construction
DONG Energy (now Ørsted) sold 50% of Westermost Rough to Marubeni Corporation (25%) and UK Green Investment Bank (25%) for GBP 240m total equity consideration, plus construction cost commitment of ~GBP 500m. Equity consideration only: GBP 240m converted at GBP/EUR ~1.17. Farm commissioned May 2015.
Evidence
From Hafrok’s transactions record
JV entry · 2017-04-20
Green Investment Group → Universities Superannuation Scheme stake not disclosed
- Stake
- not disclosed
- Consideration
- not disclosed
- Announced
- 2017-04-20
- Closed
- 2017-08
- Project stage
- operational
The Macquarie-led acquisition of the UK Green Investment Bank (agreed 20 Apr 2017, completed Aug 2017): "the Green Investment Bank will establish three new investment vehicles – an offshore wind investment vehicle ... long term infrastructure investors USS and MEIF5 will invest in the offshore wind investment vehicle ... The Green Investment Bank will remain an investor in the offshore wind investment vehicle" (Macquarie release).
Evidence
From Hafrok’s transactions record
Secondary trade · 2018-03
Marubeni → Green Investment Group 25%
- Stake
- 25%
- Consideration
- not disclosed
- Announced
- 2018-03
- Closed
- 2018-Q2
- Project stage
- operational
Green Investment Group (Macquarie) acquired Marubeni Corporation's 25% stake. GIG joined a consortium with MEIF5 and Universities Superannuation Scheme (USS) that already held a 25% stake. Consideration not publicly disclosed. After deal: Ørsted 50%, GIG/MEIF5/USS consortium 50%.
Evidence
From Hafrok’s transactions record
Portfolio sale · 2023-04
Green Investment Group (Offshore Wind Company — MEIF5's 50% LP interest) → Equitix 12.5%
- Stake
- 12.5%
- Consideration
- not disclosed
- Announced
- 2023-04
- Closed
- 2023-Q3
- Project stage
- operational
Part of Macquarie's sale of MEIF5's 50% stake in Offshore Wind Company to Equitix. Same portfolio transaction as Sheringham Shoal, Lincs, Rhyl Flats.
Evidence
- macquarie.com — Macquarie Asset Management to divest stakes in eight UK offshore wind farms ↗ 2023-04 ◆ held
From Hafrok’s transactions record
Dashed tick marks today (9 Sep 2026). The teal diamond on the spine is origination — the seabed award or round that created the project. Every other ownership event lives in the band below: one station per recorded deal, dated at its label, in deal order rather than to calendar scale. Secondary trades appear only at the interchanges; grey lines are parties whose entry or exit Hafrok’s record does not hold.
Announced-COD history: 2015-Q2→2015-07 · 2 recorded revisions · held (announced 2015-Q2, unchanged)
Revenue & offtake the regime the project was built under
Offtake regime: ROC 2.0 ROCs/MWh (subsidy expiry 2035)
A built project sells its power under the contract or support regime it was financed with; it is not expected to bid into new government offtake rounds. Where the record does not yet name that regime, the row says so rather than guessing.
Installation how the build is going · from satellite counts and Hafrok’s registers
Satellite survey
the farm as it stands, counted from satellite radar images · built before the count began, so there is no build to chart
Satellite survey
Structures standing36≈35 turbines + 1 platform expected · every expected structure seen
Surveyed2026-09-01≈from 114 satellite passes
Built2014-02 → 2015-07offshore construction to start of operation, from the record
Hafrok counts the structures standing in the sea from satellite radar images (≈) and reads the count against the turbines and platforms on record. The farm was built before this count began, so the images show it complete; they cannot date its construction. Rows marked with a dot (·) come from Hafrok’s own registers.
Satellite image
Image taken2026-09-07≈Copernicus Sentinel-1 radar satellite, northbound pass
Farm covered100%≈the whole farm lies inside the image
Structures ringed36 confirmed · 0 not yet confirmed≈as counted on 2026-09-01 · the image is newer than the count, so a bright spot without a ring may be a structure not yet counted
Construction ports
PortGrimsby Royal Dock (O&M base) ◆operations maintenance
PortGrimsby Fish Dock (construction management) ◆construction management
Contains modified Copernicus Sentinel data 2026, processed by ESA and by Microsoft Planetary Computer.
Latest satellite radar image · 2026-09-07
a radar picture, not a photograph: the sea is dark, steel is bright · black is beyond the edge of the image
confirmed structure (36)seen recently, not yet confirmed (0)probably a substation platform (a larger structure than a turbine; the register above has the facts)farm boundary
Grid connection
from Hafrok’s substation, converter and cable registers
Offshore platforms · 1
Offshore substationWestermost Rough Offshore Substation·150/33 kV · in service 2015 · owner TC Westermost Rough OFTO Limited (Transmission Capital Partners LP / International Public Partnerships)
Grid connection · ready in time?
when each part of the grid connection is due, against the start date the developer states (black line) · a bar spans the whole year, quarter or month the source gives
installed or in serviceexpected deliveryearlier date that was later moved
Sources & verification
17/18 fields verified · rests on 15 sources (13 primary) · ◆ 8 documents held
◆Verified≈Modelled◇Sourced∴Inferred⌁Convention○Unverified∅No source·Derived
Numbers are stable citation ids — grouped by source class, so they are not consecutive.
Regulator1
[19]
Department for Energy Security and Net Zero2026-05-06◆ Renewable Energy Planning Database (REPD…
“REPD Q1 2026 quarterly extract — Ref ID 2545: Site Name "Westermost Rough A", Development Status "Operational", Installed Capacity 210 MWelec, Operator "Orsted (formerly Dong Energy)"”
supportsRegister entry
Operator6
[1]
Ørsted A/S (then DONG Energy)2014-08-14◆ First 6MW turbine erected at DONG Energy…
“The first of 35 Siemens 6MW turbines has been successfully erected at the Westermost Rough offshore wind farm, a joint venture between DONG Energy (50%) and its partners Marubeni Corporation (25%) and…”
supportsTurbinesModelUnit capacityTotal capacityconstruction management
[2]
Ørsted A/S (then DONG Energy)2014-09-08◆ First power at DONG Energys Westermost R…
“2014-09-08T06:17:00.0000000Z — Electricity has been generated for the first time at Westermost Rough Offshore wind farm off the UK's East Coast, a joint venture between DONG Energy (50%) and its partn…”
supportsFirst power
[4]
Ørsted A/S (then DONG Energy)2015-05-26◆ Full power at Westermost Rough offshore …
“2015-05-26T09:00:00.0000000Z — Full power output has been achieved at the Westermost Rough offshore wind, a major renewable energy project located off the UK's east coast. Westermost Rough is located …”
supportsCommercial operationDistance from shoreCoordinates
[5]
Ørsted A/S (then DONG Energy)2015-07-01◆ Ground breaking Westermost Rough offshor…
"2015-07-01T10:30:00.0000000Z — Westermost Rough – the first offshore wind farm in the world to make commercial use of giant Siemens 6MW turbines with 75 metre blades – has been officially opened at a…
supportsCommercial operationCOD historyFoundationStatusConnection point+1 more
[7]
Ørsted A/S (then DONG Energy)2017-03-21◆ Good Energy sources wind power from DONG…
“The deal secures 12% of the output of the 210MW Westermost Rough Offshore Wind Farm operated by DONG Energy in the North Sea, enough renewable electricity to power more than 26,000 average homes. West…”
supportsMechanismDetail
[20]
National Energy System Operator (NESO)2026-07-21◆ NESO Transmission Entry Capacity (TEC) R…
“NESO TEC Register, edition 21 July 2026 - PRO-000223: "Westermost Rough Offshore Wind Farm", Status "Built", MW Connected 206.5, Effective From n/a, Customer "WESTERMOST ROUGH LIMITED"”
supportsRegister entry
Trade press8
[9]
Ørsted A/S (then DONG Energy) via GlobeNewswire2013-01-30
“DONG Energy has decided to build the offshore wind farm Westermost Rough in the North Sea on the British east coast. Offshore construction of the Westermost Rough offshore wind farm will begin in firs…”
supportsFinal investment decision
[10]
[14]
[15]
Transmission Investment
“The assets connect the 210MW Westermost Rough offshore windfarm to the 275kV electricity transmission network at Hedon substation in Yorkshire.”
supportsStatusConnection point
[16]
Power Technology2025
Press report — cited, not quoted; read it at the source link.
supportsoperatorinvestor
[17]
Power Technology (GlobalData)2015-07-23
Press report — cited, not quoted; read it at the source link.
supportsConsentConsent granted
[18]
[21]
Ørsted2025-Q2◆ Orsted — orsted factsheet asset book q2 …
“Westermost Rough (35 x SWT-6.0-154) | Arjun Infrastructure, USS, Equitix, Macquaire | 210 | 210 | 105 | Pro rata | 0.5 | 0.5 | 2015 | ROC | 2035 | - | 2”
supportsMechanismDetail