Project Type: Transmission reinforcement
Location: Argyll & Bute

Contact Details

Liaison Manager

Caitlin Quinn
Title: Community Liaison Manager
Telephone: 07901 135 758

Land Manager

Jennifer Jeffrey
Title: Senior Land Manager
Mobile: 07436 493823
Address: Inveralmond House, 200 Dunkeld Road, Perth, PH1 3AQ
Status: Project assessment

About The Project

Sloy Power Station was constructed in 1950 and is located on the western shore of Loch Lomond near Inveruglas, Argyll and Bute. The site is located within the Loch Lomond and The Trossachs National Park and can be accessed from the A82.

The SSEN Transmission substation is located to the rear of the power station building and is a four-transformer site which connect 11kV output of the hydro-electric power station to 132kV for export to the Transmission network. Sloy Power Station generates around 150 megawatts of renewable power, contributing to Scotland`s target of reducing carbon emissions.
These transformers are coming to the end of their operational life and need replacing.  The consequent deterioration in their condition poses a risk of failure, meaning the power station would no longer be able to generate renewable energy and poses a risk to the reliability of supply to customers.

Project Overview

The existing transformers were installed between 1995-1998 when engineering standards were very different.  Modern transformers are quieter and more efficient but also require more space around them for cooling and safe access for maintenance teams.  This together with the need to keep the power station connected to the network, means that a new substation site out with the existing substation compound needs to be found in proximity to the power station.

Project Elements

Delivery of this proposed project includes the following elements:

  • A new substation platform surrounded by 2.4 metre security fence.
  • A new control building.
  • Installation of four new 132kV/11kV transformers, air insulated switchgear (AIS) to connect them.
  • Connection to the existing 132kV overhead line (OHL).
  • Installation of 11kV underground cable (UC) connecting the new transformers to the power station.
  • Removal of the old transformers and associated equipment, including any redundant OHL apparatus.
  • Existing access from the A82, which may be subject to upgrade.

Community Engagement

Throughout the life of our projects, we aim to work positively with local communities and keep people informed about what we are doing. This is particularly important when we are developing a proposal and we want to understand what local people think about our plans.  
We endeavour to take the time to discuss our proposals with local community councils and the wider affected community and to carry out engagement at key stages, listening to feedback before finalising project plans.

Who is Scottish and Southern Electricity Networks?

Scottish and Southern Electricity Networks is the trading name of Scottish and Southern Energy Power Distribution Limited, Scottish Hydro Electric Transmission plc, Scottish Hydro Electric Power Distribution plc and Southern Electric Power Distribution plc.

How are Transmission network upgrades paid for?

Investments in projects are made by SHE Transmission plc. Electricity transmission companies are authorised to recover the costs of such investments through 'use of system' charges which are levied by National Grid Electricity Transmission plc on generators and suppliers of electricity. Suppliers recover their costs from all electricity customers. In order to protect the interests of customers, the transmission companies have to demonstrate to the energy regulator, Ofgem (Office for Gas and Electricity Markets) that proposed investments are necessary, are efficient and are economical so that the charges which are ultimately levied on all electricity customers are justified.

This means SHE Transmission is subject to a funding mechanism established by Parliament and regulated by Ofgem. Cross subsidies between different businesses in the SSE group is not permitted.

How are proposals scrutinised?

The Scottish Ministers are responsible for determination of applications submitted under Section 37 of the Electricity Act 1989. Both statutory consultees and members of the public have the right to submit their representations on the application. All representations will be considered by Scottish Ministers in their determination of the application.
The Office for Gas and Electricity Markets (Ofgem), as the regulator, has to approve all investment so project proposals are developed under license conditions.
Preferred route corridors chosen will comply with revised ‘Holford Rules’ which are the recognised industry approach to routeing overhead lines amended to reflect Scottish circumstances.

How and to what extent are electricity consumers' interests considered?

SHE Transmission are regulated by the Office for Gas and Electricity Markets (Ofgem), the regulator responsible for representing consumers' interests. Electricity consumer interests are therefore one of our key drivers and this is enshrined in our statutory duties under the Electricity Act.

In particular we have a statutory duty to develop, maintain and operate an efficient, economic and co-ordinated transmission system. Since the costs of these projects will ultimately be paid for by electricity consumers, we have a responsibility to take cost into account with due weighting in a comparison against other important factors.

What is the transmission network?

It’s the highest voltage electricity network in the UK – the ‘motorway network’ of the energy world. It transmits large quantities of electricity over long distances via wires carried on a system of mainly metal towers (pylons) and large substations. Transmission voltages in Scotland are 132kV, 275kV and 400kV. Larger generation schemes usually connect to the Transmission system.

The lower voltage parts of the system are called distribution networks. In Scotland, these local networks operate below 132kV whereas in England the distribution network includes 132kV. 

Feedback Period Closed

The feedback period for providing comments following our virtual consultation which was held on 24th August on our proposed Sloy Power Station Transformer Replacement project is now closed. The project team would like to extend thanks to all members of the public and stakeholders who took the time to provide feedback on our proposals. All responses received will now be reviewed by the project team and there will be further consultation at a later date.

Feedback Period Open

The project team would like to thank members of the public and interested parties who took the time to visit our online virtual exhibition on the 24th June 2021. We hope you found it informative and beneficial. The feedback period for comments and feedback on these proposals is open until Tuesday 14th September 202.
Feedback Form

Virtual Consultation Exhibition - August

SSEN Transmission are holding a virtual consultation exhibition to hear views and gather feedback on our project proposals to replace four transformers and associated equipment at Sloy Power Station. This is being held on Tuesday 24th August 2021 and further details will be available on the website nearer to this date.

Sloy Power Station Transformer Replacement Project

August Consultation Document

Related Projects: Sloy Power Station Transformer Replacement Project

File Type: pdf
Published: 17 Nov 2021
Exhibition Banners August 2021

Related Projects: Sloy Power Station Transformer Replacement Project

File Type: pdf
Published: 26 Aug 2021
Project Information Booklet August 2021

Related Projects: Sloy Power Station Transformer Replacement Project

File Type: pdf
Published: 27 Jul 2021
Consultation Event Poster - 2021

Related Projects: Sloy Power Station Transformer Replacement Project

File Type: pdf
Published: 27 Jul 2021


Sloy Power Station Feedback Form August 2021

Sloy Power Station Feedback Form August 2021

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