Celtico Welsh renewables alliance: delivery and skills takeaways for project teams
Reviewed by Tom Sullivan

First reported on The Construction Index
30 Second Briefing
Celtico has been launched as a South Wales engineering collaboration uniting 12 firms, including Ledwood Mechanical Engineering, Mainstay Marine Solutions and Pro-Steel Engineering, with a combined 1,400+ staff and £250m annual turnover to target large offshore wind, tidal range and low‑carbon infrastructure contracts. Operating as a single point of engagement rather than a merged entity, the alliance offers integrated fabrication, machining, marine engineering, coating, assembly and advanced manufacturing capacity. Backed by the Swansea Bay City Deal Skills & Talent Programme, it is tying project delivery to regional skills development to build a competitive local supply chain.
Technical Brief
- Collaboration is structured as a non-merged alliance, retaining separate corporate entities but joint client interface.
- Twelve founding firms span fabrication, machining, marine engineering, coating, assembly and advanced manufacturing disciplines.
- Founders include 3Ks Engineering, Afon Engineering, JES Group, King Site Services and Ledwood Mechanical Engineering.
- Mainstay Marine Solutions, Mii Engineering, Pro-Steel Engineering and Rhyal Engineering add heavy marine and structural capability.
- Site Heat Treatment Services, Techno Engineering (Jenkins & Davies) and Weldlec contribute specialist heat-treatment and electrical services.
- Additional South Wales engineering companies are already in discussions to join, indicating planned capacity scaling.
- Skills pipeline is coordinated via the Swansea Bay City Deal Skills & Talent Programme and Regional Learning & Skills Partnership.
- Model is explicitly designed to package work at a scale suitable for major offshore wind and tidal range contracts.
Our Take
Within our 745-item Infrastructure database, Wales appears far less frequently than English regions, so a 12-firm cluster like Celtico signals a deliberate attempt to build a recognisable regional supply chain brand rather than compete as isolated SMEs.
A collective annual turnover of about £250m across companies such as Ledwood Mechanical Engineering, Mainstay Marine Solutions and Rhyal Engineering is large enough to prequalify for many UK-scale renewables frameworks, which could shift some work away from Tier 1 contractors based outside Wales.
The involvement of the Swansea Bay City Deal Skills & Talent Programme and the Regional Learning & Skills Partnership suggests that future renewables projects in South Wales may be able to evidence local content and skills pipelines more robustly in bids, which is increasingly important in sustainability-tagged infrastructure procurements in our coverage.
Prepared by collating external sources, AI-assisted tools, and Geomechanics.io’s proprietary mining database, then reviewed for technical accuracy & edited by our geotechnical team.
Related Articles
Related Industries & Products
Construction
Quality control software for construction companies with material testing, batch tracking, and compliance management.
Mining
Geotechnical software solutions for mining operations including CMRR analysis, hydrogeological testing, and data management.
QCDB-io
Comprehensive quality control database for manufacturing, tunnelling, and civil construction with UCS testing, PSD analysis, and grout mix design management.


