Keeping the power flowing in remote Scotland

In partnership with our client, SSEN Transmission (Scottish and Southern Electricity Networks), we brought two years of hard work to a close, completing the restringing of the 87km long Loch Buidhe to Dounreay overhead transmission line in the North of Scotland. Despite the new constraints in place due to the COVID-19 pandemic, the construction work was completed ahead of programme, and the project was awarded both Scottish Gold and National Silver in the Green Apple Environment Awards for its careful consideration in minimising impacts on local wildlife and their habitats.

The Loch Buidhe to Dounreay overhead line has played a vital role in Scottish’s energy story for over half a century, first constructed in the 1950’s to transport energy generated at Dounreay Nuclear Power station. It was one of the first major arteries of the transmission network in the North of Scotland and played a vital role in reliably transporting electricity over a long distance from where it was generated to where it was needed.

When Dounreay closed in 1995 it wasn’t the end of the story for the line, with several hydro stations already connected to the line transporting clean energy, and new wind power looking to connect to the national grid in the coming years, it was yet to play its most significant role, facilitating the transition to net zero.

Typically, the transmission towers will last for about 80 years, whereas the conductors, insulators and fittings normally last for about 40 years. Each overhead line will usually go through at least one refurbishment during its lifespan. It is SSEN Transmission’s priority to safely deliver a robust, efficient and reliable network to its customers in the most sustainable way- they will always look to refurbish and will only build a new line if a refurbishment is not feasible.

The line travels over some of Scotland’s most challenging and remote terrain, facing some of the country’s harshest weather, and traverses 16 nationally and internationally designated nature conservation sites as well as undesignated areas that support ecologically important flora and fauna. To reach each transmission tower, and to keep within standard environmental protection measures, the team employed the services of local helicopter company PDG who would fly material and equipment up to each remote tower location to allow the team to carry out the work.

Using helicopters enabled the team to adhere to environmental protection measures, mitigating the impact of constructing long access tracks to facilitate the works. Not only were helicopters used to protect the local habitat, but drones were used to observe and monitor an osprey family, as well as hen harrier and blanket bog peatland habitats, ensuring that construction did not disrupt the legally protected birds during a critical breeding season. As a result, the osprey nest successfully reared two healthy chicks, and the project’s commitment to environmental conservation was recognised by The Green Apple Environmental Awards, commending Wood for their environmental diligence. The award also recognized biosecurity decontamination regimes and the use of eco welfare units, solar technology, eco generators, and auto operation which were implemented to reduce power usage and carbon footprint throughout the process.

Wood is actively minimising its environmental impact to contribute positively towards the global sustainability of the planet we all share. We have been working closely with the European Commission for over 20 years to develop and implement global policies and legislation which protect the environment and its biodiversity. Our health, safety, security and ethics policy sets out this commitment and our approach focuses on reducing our overall impact while raising environmental awareness and competence amongst our workforce. By bringing together policy analysts and technical specialists from a range of disciplines within Wood, we are shaping more effective and environmentally protective regulation and enforcement of legislation at the national level.

This project truly demonstrates how essential work can be undertaken within ecologically sensitive habitats without adversely affecting the local environment and wildlife.

During activity on the Loch Buidhe to Dounreay overhead line, the safety of the team carrying out the work was paramount. The project was completed over two years with no “lost time injuries,” reflecting an excellent safety performance and proving that the safety of both our project teams and local habitats can simultaneously be prioritized while completing high-quality work to schedule.

As we work towards a net-zero world, we believe that other organisations can benefit from using the methods outlined here in order to protect local environments, and ensure the safety of project teams, creating a more sustainable and resilient future for all.