Beauly – Denny 2nd Circuit Upgrade Braco West

As a result of the Scottish and UK Governments’ Net Zero climate change targets, together with requirements set out in the  British Energy Security Strategy (BESS) (April 2022 ) and subsequently in National Grid’s, the Electricity System Operator (ESO),  “Pathway to 2030” Holistic Network Design (HND) (July 2022),  significant increases in renewable generation capacity are required across the UK, resulting in significant investment in new transmission network infrastructure to transport this energy and reinforce the network.  

The UK and Scottish Government has offshore wind targets of 50GW and 11GW, which need to be delivered by 2030 to make the transition to net zero emissions. For the north of Scotland, there is the need for over £7bn of investment in onshore electricity transmission infrastructure. With these major projects required to deliver the 2030 targets, accelerated delivery is required to meet the government’s connection dates.

Click the play button to watch our video and to learn more about the work SSEN Transmission is doing to deliver Net Zero.

Click the play button to watch our video and to learn more about our Pathway to 2030 Projects

This storyboard map has been prepared by Scottish and Southern Electricity Networks Transmission (SSEN Transmission). SSEN Transmission, operating under licence held by Scottish Hydro Electric Transmission plc (SHE Transmission), owns, operates and develops the high voltage electricity transmission system in the north of Scotland and remote islands.

SSEN Transmission is proposing to upgrade the existing Beauly-Denny 275kV circuit to 400kV to mirror the ratings of the existing 400kV circuit which runs along the route. The upgrade can make use of existing OHLs infrastructure but requires alterations/additions to several associated substations including at Braco West.  

SSEN Transmission is therefore proposing a new substation site near the existing Braco West substation as there is insufficient space on the existing site at Braco West to accommodate the additional equipment associated with the wider 400kV upgrade. The new substation site is required to be in proximity of the existing substation to tie back into it. Whether this will be via OHL or underground cable (UGC) has not yet been determined and will depend on its location. 

Implementing the proposed development of a new substation in proximity to the existing Braco West Substation to house the equipment required to enable the large-scale upgrade will comprise the following: 

• 400kV transformers and a new 400kV double busbar; 
• Current indicative platform size for an Air Insulated Switchgear Substation (AIS) is approximately 380 x 315m. These are taken to comprise a working ‘worst case scenario for site selection’. Earthworks would be required to develop the level platform;   
• Removal of some of the equipment from the existing 275kV Braco West substation, with the control building likely to remain; 
• Overhead line tie ins from the new substation to the existing Beauly – Denny overhead line; and  
• Upgrade existing or provide new access tracks, temporary construction compounds and construction laydown areas.

The selection process has followed formal internal guidance to enable a consistent and rigorous selection of alignments and sites for new substations, switching stations and converter stations. The site selection process has three key stages, each increasing in detail and definition. Technical, environmental, and cost considerations are brought together in a way which seeks the best balance in accordance with SSEN Transmission’s Network Operator’s Licence and the Electricity Act 1989. This staged process leads to the identification of a finalised proposed substation site, which will be taken forward for planning. An overview of the substation Site Selection Process is provided in the image below

We understand and recognise the value of the feedback provided by members of the public during all engagements and consultations. Without this valuable feedback, the project development team would be unable to progress projects and reach a balanced proposal.

We are keen to receive your views and comments in regards to the following questions: 

• Has the requirement for the project been clearly explained?
• Are there any additional factors, concerns, or environmental features that you consider important and should be brought to the attention of the project team?
• Based on the information provided do you agree with option 2 being taken forward to develop further?
• Following review of the provided information, how would you describe your understanding of the project?
• Overall, how do you feel about the project?

Your views and comments can be provided to the project team by completing the feedback form and sending to our Community Liaison Manager. An online feedback form can be completed here:  Braco West 400kV Substation Aug 2023 Online Feedback Form .

Alternatively, a form can be downloaded by clicking the button below:

Please submit your completed form by one of the methods below:

• Post: Grampian House, 200 Dunkeld Road, Perth, PH1 3GH
• Email: BDUP@sse.com
• Online:  ssen-transmission.co.uk/projects/project-map/beauly-denny-400kv-upgrade 

All feedback received will be assessed and the proposed options adapted where necessary.

We will be seeking feedback from members of the public on this project until 3rd October 2023