Erebus Floating Wind Project in Celtic Sea, UK

Project title: Erebus Floating Wind Project 

Project location: Celtic Sea, UK

Client: BlueGem Wind – Simply Blue Energy and Total S.A.

Project Summary: In February of 2020, OWC was contracted to provide pre-FEED owner’s engineering and project development services to Simply Blue Energy and Total’s Erebus floating wind project located in the Celtic Sea. Following our successful role guiding the project through this phase, OWC entered another large contract, in November 2021, to provide owner’s engineering services for the FEED phase of the floating wind project.  

About the wind farm

Erebus is a floating offshore wind project in the Celtic Sea, 75 km from the Pembrokeshire coast, Wales. The project will feature new floating wind technology, 14MW turbines, and an installed capacity of up to 100MW. This project is one of the largest floating wind projects in Wales with an expected operation date of 2027. Although the project is considered a demonstration project, Erebus is significant to the area as it is the first project to tap into the 4GW of wind potential in the Celtic Sea. 

Our scope of work

Through the pre-FEED and FEED stages, OWC provided owner’s engineering and project development support services, including: 

  • Management of onshore and offshore consenting 
  • Procurement and management of geotechnical, geophysical, and metocean site surveys 
  • Energy yield analysis and metocean management 
  • Offshore and onshore layout design and optimisation 
  • Electrical network design and associated studies 
  • Grid management support 
  • Ports and assembly strategy together with stakeholder engagement 
  • Transport & installation studies 
  • Operations and maintenance strategy development and modelling 
  • Subsea array and export cables together with landfall studies 
  • Project cost modelling 
  • Comprehensive package management, engineering and project management functions (e.g. risk, interface, schedule) 

Key roles as an integrated team:

  • Owner’s Engineer, including Principal Designer 
  • Package Managers 
  • Engineering Manager 
  • Risk & Interface Management 


As offshore wind gains traction globally, developers explore new technologies to tap into additional offshore wind potential. OWC’s team has supported the developers of the Erebus wind project apply floating wind technology to access wind resources in the deeper waters of the Celtic Sea. With new technology comes new challenges. Blue Gem Wind contracted OWC to help face these challenges as we have immense experience and expertise with floating wind technology. 

  • Technology maturity and development risks 
  • Supply chain requirements  
  • Consenting – aligning technical and consenting requirements 
  • Environmental and site conditions i.e. deep waters 
  • Ports infrastructure, transport and installation 
  • Operations and maintenance and the unique challenges of floating wind 

Value added

OWC provides unique value to each project to ensure our Client’s success. With OWC’s support, Blue Gem Wind was granted the first marine license and Section 36 for floating offshore wind in Wales. 

Broad-ranging technical, engineering and consenting support through an integrated team model 

Client access to specialists from across the broader ABL group and extensive international floating wind project expertise  

“We are pleased to continue the relationship with OWC and partners. Project design and development is a core skill of the UK supply chain, and we are delighted to award this contract to a UK business.”​

David Groves, Commercial Manager, Blue Gem Wind 

“We see the continued collaboration with OWC as an important step in submitting our planning consent for Erebus in December and preparing the project for construction.”​

Mike Scott, Project Managing Director, Blue Gem Wind 

Related services

Owner’s Engineering

Owner’s Engineering

Our owner’s engineering ensures your project runs on time, on budget and according to your objectives.


OWC draws on a vase range of engineering expertise to provide you with specialist engineering and analysis across every stage of a renewable project’s lifecycle.


Dedicated multi-disciplinary geoscience team covering geotechnical, geophysical, geospatial engineering, supporting renewable energy projects in understanding and mitigating their ground risks.

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