Peterhead Substation

Client: SSEN Transmission

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We were the Civils subcontractor on this 2-part project, working for Balfour Beatty Utility Solutions Ltd, the Contractor.

Part A was for the design of a substation platform, buildings and infrastructure; also design and construction of access to enable public road improvement works.

Part B of the project was for the construction of 400kV busbar extension works including earthworks, substation platform, drainage, ducts, roads, transformer bunds, a GIS building and two transformer buildings.

The scope included earthworks for the substation platform, construction of reinforced concrete (RC) bunds for two 400/275kV Supergrid Transformers as well as associated roads, drainage with SuDS pond, landscaping, public road improvements, pre-cast service trenches, ducting, drawpits, fencing, and concrete foundations for AIS & GIB structures. 

GIS Building scope of works included extensive areas of raised access flooring, battery room and main GIS hall with ducting provision between main relay room areas and cable termination locations on each GIS Bay. Design and installation of ventilation provision for all three buildings with natural ventilation employed where possible, with minimal areas of mechanical ventilation installed.

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Principal Elements

• Earthworks platform 210x150m

• Transformer buildings 2 no. (2,800m2 each)

• Security fencing 670m

• GIS building 2,000m2

• Earthworks Cut Volume 75,000m3

• Landscape Bunds 59,100m3

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Points of Interest

• The site is located on an area previously utilised as the construction compound for the construction of the nearby Peterhead Power Station in the 1970s.

• Redundant electrical cables required to be cleared from the platform footprint to allow safe commencement of earthworks.

• Given historic use of platform area ground conditions were variable. This required continual monitoring and frequent testing in order to ensure adequate construction layers were provided in order to meet the required formation level bearing capacity in line with the Employers Earthworks Specification.

• Lesser quality materials excavated from the platform extents were placed locally in landscape screening bunds assisting in reducing the visual impact of the development.