Project Overview

The Pen y Cymoedd Wind Energy Project is a 76 turbine development located within Rhondda Cynon Taf and Neath Port Talbot. Once operational the project will generate enough electricity to meet the domestic need of 140,000 homes. 

Dawnus were employed by ABB Ltd to design, supply and construct two substations; Pen y Cymoedd Substation and Rhigos Substation. 

The works included the design and construction of large scale earthworks including approximately 20,000m3 of rippable rock excavated and processed for re-use, reinforced concrete foundations including large generator transformer foundations, and site infrastructure including access roads, drainage, service connections and landscaping.  

We also delivered the design and construction of three new buildings within the respective sites including all architectural, mechanical, electrical and plant design and civil elements. At the Pen y Cymoedd site we constructed a control building which houses the control equipment for the wind farm, and an operations and maintenance building. At the Rhigos site we constructed a smaller control building. 

Our scope of works also included the design and construction of the following: 

  • Earthworks and plateau construction including internal roads, hard standings and site finishes
  • Design and installation of security fencing
  • Site services such as storm drainage including attenuation systems and bund water control units, assistance with gaining LPA approvals for designed systems, foul drainage including oil containment water systems and separators
  • All HV, LV and communication ducting, cable troughing and external lighting system design
  • Potable water main at Rhigos as well as a well point dewatering system at Pen y Cymoedd, including firefighting systems as required
  • All reinforced concrete foundations for HV equipment including Generator Transformer bunds (400kV and 132kV), all AIS equipment and support structures
  • Site investigation works
  • Hard and soft landscaping
  • Temporary works 

All civil engineering and hard landscaping works were delivered by directly employed staff, site operatives and plant operatives.

Project Gallery





Project Value


Contract Period

95 weeks