Inspections, Maintenance & Repair (IMR)

CWind has a robust track record of experience delivering Subsea & Topside Inspections, Maintenance and Repair (IMR), utilising owned assets, best people and proven procedures, delivered through one interface

CWind has an established track record of successfully delivering subsea and topside balance of plant (BoP) solutions that actively increase efficiencies, improve turbine utilisation and reduce turbine downtime.

With access to Group assets, engineering teams, adept project managers, and highly skilled, local technicians, CWind effectively reduces safety risk and simultaneously reduces the number of turbine visits, increasing efficiency and turbine optimisation.

Project coordinators can be permanently situated on site as a client focal point, providing greater strategic support and resulting in improved dialogue with the planner and capable interface management.

Typically, as assets age, associated maintenance costs increase. With a significant number of offshore wind assets entering the later stages of the project lifecycle, it is evident that balance of plant degradation is a growing industry challenge.

Optimising efficiencies and maintaining the structural elements which support the wind turbine generator is crucial to ensure asset life is maximised. Without regularly scheduled maintenance, offshore wind assets can deteriorate, causing faults requiring reactive maintenance leading to downtime and loss of revenue.

CWind provides statutory inspections, pro-active maintenance, and pre-emptive repairs to ensure optimal asset integrity and overall longevity of an offshore wind project.

Working with clients, CWind delivers flexible, turnkey solutions, designed around specific wind farm sites, utilising an experienced fleet of in-house multi-purpose CTVs, highly skilled technicians, and project managers with a robust track record of successful project delivery.

CWind has experience at over 50 offshore wind farms across the UK and Europe, providing service support for 13GW of power since 2009, with an extensive track record of O&M delivery, including a long-term maintenance contract at Westermost Rough. Supported by Global Marine Group shared services, equipment and assets, CWind is well versed to deliver large scopes of maintenance projects, including marine logistics, foundation inspection and preventative maintenance.

Our Key Capabilities:

  • Retrofits and snagging
  • Corrosion protection
  • Statutory inspections
  • Scheduled routine maintenance
  • Preventive & Reactive maintenance
  • Marine co-ordination & logisitics
  • Cleaning
  • Coating repairs
  • Bolting
  • HVAC
  • HV/LV Services
  • Blade repair
  • Fire and life-saving systems
  • Troubleshooting and repair
  • ROV operations
  • Bathymetric surveys
  • Cable crossings
  • Live monitoring
  • Cable burial depth
  • Anodes and cathodes
  • Cable Protection System (CPS)
  • Foundation inspections

Statutory Inspections

Vigilant attention to detail, topside and subsea

It is critical, that inspections are performed by experienced, methodical experts alert to every detail.

The implications if a wind turbine is offline for unscheduled maintenance can be approximately £10,000 in lost revenue a day, and when factoring in the additional costs of support vessels, technicians and equipment for repairs it could run into the millions.

For large-scale wind turbine assets and auxiliary equipment, unaddressed minor problems or oversights can quickly escalate into costly stoppages, lost revenue and expensive repairs.

CWind is on hand for both scheduled and unscheduled maintenance with fully trained technicians for turbine, cable and foundation maintenance, utilising a dedicated fuel-efficient fleet of purpose-built CTVs; all the elements required to complement OEM contracts in one bespoke package.

CWind takes the headache out of preparing, planning and executing inspections with comprehensive packages tailored to each customer and project requirement.

Our independent, certified inspectors use state-of-the-art equipment and years of experience to fully document and report defects, helping to create optimised maintenance plans.

Our turbine technicians undertake 100 and 500 hour servicing, gearbox inspections, generator alignment, “wet” service, pitch cylinder inspection & change out. Our specialist technicians also perform endoscope inspections and evaluations on gearboxes and main bearings’, minimising turbine down time.

CWind’s partnerships with key qualified specialists facilitates our statutory inspection works. These works range from simple inspection and certification of lifting equipment and self-retracting lanyards, to inspection and certification of life saving equipment.

CWind has extensive experience, a can-do approach and a proven track record in inspections of steel structures. CWind is currently providing statutory inspection teams for all of the offshore wind farm sites for a major European developer, and a 20-year contract for above water structural inspections and maintenance services at Westermost Rough offshore sub-station for Transmission Investment. Previously, CWind held a two-year contract for all above water structural and statutory inspections and maintenance services for E.ON at Humber Gateway Offshore Wind Farm.

Our Key Capabilities:

  • Critical components including endoscopic analysis
  • Root cause analysis
  • Oil evaluation
  • Blade inspections
  • Fall protection and anchor bolts
  • Davit cranes
  • Personal protective equipment
  • Visual, video and photographic surveys
  • Sub-surface ROV surveys
  • Non-destructive testing and inspections
  • Marine growth inspections
  • Balance of plant including paint, equipment and structural inspections
  • Pre-warranty, insurance and end-of-warranty inspections
  • Anode inspections
  • Assessments before, during and after construction
  • Creation of optimised maintenance plans
  • Working in line with international industry standards
  • O&M support for more than 6GW of power generated by the offshore wind sector

Subsea Survey Solutions

Maximising time on site to deliver customers more

Not only can a post-installation survey be a requirement set out in the licence issued by the relevant Marine Authority, but also a pre-requisite where cable installation design cannot fully mitigate the risk of cable exposure.

Post-installation monitoring surveys can also be carried out periodically to minimise future threats and identify preventative action that can be implemented, improving reliability and reducing un-budgeted costs.

From a fleet of 17 CTVs strategically positioned around the UK and Europe, we offer these survey solutions to energy developers and owners to provide a detailed insight into seabed conditions. Completing the surveys from vessels already located at the wind farms, make it a cost effective solution that maximises the benefits of time on site.

Customers gain from using vessels and crews with experience of their sites, with many operational approvals already in place. Our survey solution also eliminates transit times to site and minimises risk of weather delays.



Scour condition monitoring and volume calculations are performed using high resolution multi-beam bathymetry MBES and side-scan sonar SSS surveys around WTG foundations. This is often where tidal currents have removed material which might compromise the security of foundations or exposed cables. 2D/3D images, maps and volumetric calculations of material moved are produced, at acquisition speeds of 3-4 knots.


The use of multi-beam and side-scan sonar surveys to detect cable exposure and measure depth of sediment cover over cable by comparison of seabed with previous surveys. Use of high resolution MBES digital terrain models, with highly accurate vertical correction for tides to monitor cable depth of cover without the use of ROVs. Acquisition speeds of 3-4 knots.


Cable crossing condition, CPS protection monitoring and depth of burial verification surveys using ROV based tools such as TSS 440/350, Innovatum Smartrak or the Pangeo 3D Seismic system.


Analysis of infauna (subsurface) sampled by grabs or cores and the epifauna (above surface) sampled by trawls or dredges, accompanied by the sub-sampling of sediments for analysis of particle size distributions and contaminant concentrations.

Our Key Capabilities:

  • Assessing the burial status of the cable and determining cable exposure/free-spanning or monitor existing exposures/spans
  • Identifying cable damage
  • Assessing the burial depth of the cable
  • Assessing scour in the vicinity of the substation
  • Assessing mobile sediment movement and sediment level changes (scour/erosion/accretion) from previous surveys
  • Updating the ground model to review sediment level changes and trends
  • Assessing the condition of existing remedial works
  • Identifying potential hazards in the vicinity of the cable and offshore substation
  • Monitoring identified sensitive habitats
  • Monitoring identified areas of archaeological interest
  • Reporting on maintenance works required
  • Providing seabed information in order to assess any third party compensation claims
  • Delivering consent compliance
  • Delivering third party pipeline, cable or other crossing agreement compliance

ROVCO Invested Partnership

CWind can deliver cost effective, flexible solutions using cutting edge technology for subsea balance of plant to meet customer requirements

Through our invested partnership with Rovco, the world’s leading provider of ROV and hydrographic surveys using 3D and AI, CWind provide advancements to the offshore renewables industry through the continuous improvement of available and future-proofed digital technology.

Our invested partnership minimises risk to offshore personnel, through smarter ways of working, reducing the amount of time spent offshore.

Additionally, we provide optimised state of the art live 3D vision technology to acquire accurate, high quality data, delivered from a fleet of multi-purpose vessels and ROVs using highly experienced personnel.

Together, CWind and Rovco empower clients with an improved understanding of offshore wind assets, supporting industry behaviour change, to make timely, informed decisions throughout the project lifecycle.

Utilising trend analysis, we can identify likely faults on subsea structures, as well as within the internal environment of the monopile.

Applying our intelligence to support pre-emptive asset maintenance and fault prediction, ensures effective asset management and maximised integrity, providing clients with peace of mind.

We offer a proactive approach to digital data management, utilising already deployed vessels to optimise existing offshore operations, maximise resource and add value to projects.

We have strategically located vessels, and technical knowledge, to deliver global subsea solutions, responding rapidly to meet client needs.

As part of the Global Marine Group, CWind has a legacy of successful project delivery across multiple markets; continually evolving subsea solutions utilising engineering excellence and transferrable cross-market knowledge.

Our Key Capabilities:

  • Seabed scour survey
  • Subsea marine growth survey
  • Subsea screening inspection of primary and secondary steelwork
  • Subsea close inspection of primary and secondary steelwork
  • Cathodic protection potential survey
  • Detailed anode survey
  • Close visual inspection of the grouted connections
  • Inspection of the cable protection and route system
  • Inspection of Innovative Cable Protection System (Tektube)
  • Inspection of the J-tubes, cable protection and route system
  • Geophysical survey of the array cables corridor
  • Geophysical survey of the export cables corridor


CWind Services

Cable Pull-In

Experienced technicians who can work quickly yet handle your precious array, export and PCC cable with care. Over 890 pull ins, as a group, to date.

Corrosion Protection

Full corrosion protection services, inspection, procurement, application and transportation to maximise asset lifetime

Temporary Power

Temporary power for turbines far out to sea allowing for smooth, uninterrupted construction and maintenance

Subsea Survey Solutions

Utilising the CTV fleet to undertake subsea surveys, a cost effective solution maximising the benefits of time on site

Topside Inspection, Maintenance and Repair

CWind has a robust track record of experience delivering Topside Inspections, Maintenance and Repair (IMR), utilising owned assets, best people and proven procedures, delivered through one interface

Subsea Inspection, Maintenance and Repair

Optimised, flexible solutions using cutting edge technology for Subsea Inspections, Maintenance and Repair (IMR) to meet customer requirements

Cable Termination & Testing

Optimising time, avoiding extra costs and ensuring safety requires planning and preparation, as well as technical, logistical and project management expertise.

Crew Transfer Vessel Charter

Transporting technicians quickly and safely, to and from site with a fleet of 17 vessels

Offshore Wind Training

One-stop accredited training centre offering bespoke courses to the on and offshore wind industry including confined space and rescue

Our Latest News:

Posted: 04/11/2020

CWind completes 2020 works at East Anglia ONE Windfarm

CWind, part of the Global Marine Group, has completed this year’s...

Posted: 21/10/2020

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Posted: 21/09/2020

Global Marine Group Launches OceanIQ Consultancy Business – utilising rich subsea data

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Posted: 25/08/2020

Ten years of CWind

From humble beginnings in a Brightlingsea shipyard, to an international company...

Posted: 25/08/2020

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THE NEXT DECADE Throughout its 10-year history, CWind, part of the...

Posted: 14/07/2020

Group Annual Awards 2020

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Posted: 14/07/2020

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Adapting and collaborating with our supply chain partners to build the Hybrid SES

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Posted: 08/06/2020

OREAC: 1,400 GW of offshore wind is possible by 2050, and will be key for green recovery

The Ocean Renewable Energy Action Coalition (OREAC) is an initiative led...

Posted: 20/05/2020

Adapting to ensure a continuation of service during COVID-19

As the COVID-19 pandemic continues to affect businesses and individuals globally, like everyone,...

Posted: 14/05/2020

Maintaining Power in a Crisis

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Posted: 22/04/2020

CWind continues fleet expansion to enable robust maintenance of vital power networks

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CWind Scottish Power Renewables EA1 offshore wind farm
Posted: 15/04/2020

Scottish Power Renewables announces CWind East Anglia One contract award

CWind is delighted to share Scottish Power Renewables’ latest press release...

Posted: 24/03/2020

Adapting to ensure a continuation of service: Our response to COVID-19

In light of recent developments and UK Government guidelines, we wanted...

Posted: 02/03/2020

J.F. Lehman & Company acquires Global Marine Group

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Posted: 13/01/2020

Ocean Renewable Energy Action Coalition Launches to Accelerate Global Offshore Wind Capacity

An international Ocean Renewable Energy Action Coalition has been formed to...

Posted: 18/12/2019

Renewable energy’s rising stars win seats on RenewableUK’s new Shadow Board

CWind is pleased to share RenewableUK’s latest press release regarding the appointment...

Posted: 11/12/2019

Engineering the next steps on the path to zero-emissions CTVs

The zero-emissions goal is shared by many companies in the offshore...

Image of Paul Redpath, Project Manager at CWind
Posted: 21/11/2019

My life in offshore wind: Paul Redpath, Project Manager, CWind

As a relatively young industry, offshore wind attracts people from a...

Posted: 16/10/2019

CWind secures contract to deliver world’s first hybrid propulsion SES to Ørsted

CWind announced today a long-term charter contract agreement with Ørsted, delivering...

Posted: 15/07/2019

Global Marine Group to Ride 500km for corporate charities the JST and the Ninos Pag-Asa Orphanage

Next week, a team of 26 amateur and enthusiastic riders from...

Posted: 25/06/2019

Global Marine Group to Safeguard Ørsted’s UK Power Cables Under the Atlantic Cable Maintenance Agreement

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Posted: 08/03/2019

Meet some of our inspirational ladies on International Women’s Day

In 2019, the focus of International Women’s Day is about balance....

Posted: 28/02/2019

Osbit to deliver next generation Subsea Plough to Global Marine Group

Osbit Limited, the offshore technology and engineering company, has secured a...

Posted: 04/02/2019

CWind Digitises Critical Operations With CrewSmart

CWind is pleased to share CrewSmart’s latest press release: Leading provider...

Posted: 29/01/2019

Rovco and Global Marine Group Enter Invested Partnership

Subsea technology company, Rovco has formed an invested partnership with Global...

ORE Catapult Levenmouth Turbine
Posted: 24/01/2019

CWind & ORE Catapult Drive UK Offshore Wind Technology Innovation

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Posted: 05/11/2018

Feature: RenewableUK array & export cables project intelligence report

Our Director of Power Cables, Andrew Lloyd, features as part of...

Posted: 23/10/2018

CWind Taiwan Completes Inaugural Contract at Yunlin Offshore Wind Farm

CWind Taiwan, a joint venture between CWind and International Ocean Vessel...

Posted: 15/10/2018

ASV Pioneer sails for her maiden project

A couple of weeks ago, the ASV Pioneer, part of our...

Posted: 24/09/2018

CWind to provide fast-response cable repair to Vattenfall’s European portfolio

CWind, a leading provider of power cable and asset management services...

Posted: 01/08/2018

Global Marine Group handed RoSPA Order of Distinction (19 consecutive Golds) Award for health and safety practices

Global Marine Group has been issued a prestigious award in recognition...

Posted: 24/07/2018

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For the last couple of weeks, Megan, an A level student...

Posted: 05/07/2018

Global Marine Group to Ride 350km for corporate charity, the Jubilee Sailing Trust

Next week, a team of amateur and enthusiastic riders from Global...

Posted: 04/07/2018

Celebrating the successes of our people

At the end of June we held our Annual Awards Evening...

Posted: 14/05/2018

CWind to provide Complete Cable Care service to Transmission Capital Partners

CWind, a leading provider of power cable and asset management services...

Posted: 03/05/2018

CEO Today Magazine Announce Ian Douglas as a European Award Winner 2018

Ian Douglas Wins CEO Today Magazine European Awards CWind, part of...

Posted: 12/04/2018

Contract Awarded for Sub Sea Cable Replacement in Orkney Isles

CWind is pleased to share Scottish & Southern Electricity Networks’ latest press...

Posted: 10/04/2018

CWind launches new cable care service with dedicated cable repair barge

CWind, a leading provider of power cable and asset management services...

Posted: 29/03/2018

Key offshore wind players sign loI for GWO training centre in Taiwan

Our Joint Venture company, CWind Taiwan, signed a Letter of Intent...

Posted: 14/02/2018

Global Marine Group presented prestigious Shipowner of the Year Award by Offshore Support Journal

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CWind Taiwan
Posted: 25/01/2018

CWind and International Ocean Vessel Technical Consultant form joint venture CWind Taiwan

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Posted: 20/12/2017

Global Marine Group announces new business unit ‘Global Offshore’ to serve the oil & gas sector

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CWind: Offshore power market
Posted: 01/12/2017

Global Marine Group completes acquisition of Fugro’s trenching and cable lay business

Acquisition Further Positions Global Marine Group for Significant Offshore Power Market...

CWind: Offshore safety
Posted: 07/11/2017

Global Marine Group launches new Safety Management System

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GM to grow as leading provider in renewables market
Posted: 12/10/2017

Global Marine Group to acquire Fugro’s trenching and cable laying business

Acquisition further positions company for significant offshore power market opportunities Chelmsford,...

Posted: 08/09/2017

CWind Awarded TP Gate Contract

Two DONG Energy offshore wind farms set to benefit from CWind...

Posted: 05/09/2017

Global Marine Group Awarded Order of Distinction from Royal Society for the Prevention of Accidents

Chelmsford, Tuesday 5 September 2017. The Global Marine Group (GMG), a market...

Global marine: offshore wind expansion
Posted: 31/08/2017

Global Marine Group Chooses Port of Blyth to Extend UK Footprint

Chelmsford, Thursday 31 August 2017. The Global Marine Group (GMG), a market...

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Posted: 17/08/2017

Global Marine Group Secures Cable Contract for Rampion Offshore Wind Farm

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Posted: 08/08/2017

CWind Secures Major Cable Pull-in Contract at Merkur Offshore Wind Farm

Chelmsford, Tuesday 8 August 2017. CWind, a leading provider of services...

Posted: 03/08/2017

Utilising the Q1000, CS Recorder Completes Cable Reburial Project in Three Weeks

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Posted: 03/08/2017

Global Marine Group to Ride Over 200 Miles for Children’s Charity Brainwave

Chelmsford, Wednesday 2 August 2017. Employees of the Global Marine Group (GMG),...

Posted: 03/07/2017

CWind Announces Two-Year Crew Transfer Vessel Extension on Key Offshore Wind Farm Project for Dong Energy

CWind, a leading provider of services to the offshore wind industry,...

Posted: 06/05/2017

Global Marine Group Reports Busy Spring Period

Heading into the summer months with resources engaged around the globe....

Posted: 02/05/2017

CWind Reaches Halfway Point of 15 Month Secondary Works Contract for Iberdrola’s Wikinger Offshore Wind Farm

CWind, a leading provider of services to the offshore renewables industry...

Posted: 25/04/2017

CWind Completes Vital Power Cable Repairs to Reconnect over 2,000 Scilly Islanders

CWind, a leading provider of services to the offshore renewables industry...

Posted: 16/02/2017

CWind Invests in Largest Crew Transfer Vessel to Date

CWind, a leading provider of services to the offshore wind industry,...

Posted: 14/02/2017

Introducing power cable capabilities to the CWind service scope

Positioning ourselves to meet wider customer needs As you may have...

Posted: 13/02/2017

CWind to Deliver Global Marine’s Power Cable Capabilities

CWind, a leading provider of services to the offshore wind industry,...

Posted: 26/01/2017

CWind Supports Centrica Jack Up Operations from Grimsby Hub

CWind, a leading provider of services to the offshore wind industry,...

Posted: 04/01/2017

CWind Provides Crew Transfer Vessels for EON Blade Maintenance Work at Robin Rigg

CWind, a leading integrated service provider in the offshore wind industry,...

Posted: 08/12/2016

CWind provide CTVs for Siemens Blade Maintenance Campaign

CWind, a leading provider of services to the offshore wind industry,...

Posted: 05/12/2016

CWind Provides ROV Subsea Inspections for E.ON at Amrumbank West

CWind, a leading provider of services to the offshore wind industry,...

Posted: 22/11/2016

CWind Wins Contract To Undertake Secondary Works For Geosea At Galloper Offshore Wind Farm

CWind, a leading provider of services to the offshore wind industry,...