Connecting the future of efficient power in Northwest Scotland

Lamifil delivers high-tech ACCC® Conductor for award-winning reconductoring project

First commissioned over 70 years ago, you could say a lot has changed since the original high-voltage overhead transmission line was installed between Scotland’s Fort Augustus and Fort William. Marked growth in both the local manufacturing and renewable energy sectors has resulted not only in increased demand but also a shift in the distribution of production. So to complete the challenging refurbishment of the line on behalf of SSEN Transmission, EPC contractor Balfour Beatty called on the expertise and proven innovation of Lamifil. The result? A successful doubling of capacity on the line with minimal impact to the local community and environment, paving the way for future growth in renewables. A result which Utility Week happened to recognise with the Capital Project of the Year Award 2020.

Doubling the capacity while minimising costs and impact

The 44km route from Fort Augustus to Fort William cuts through the heart of some of Scotland’s most rugged and inaccessible terrain. Essentially connecting the country’s North Sea and Irish Sea coastlines along the historic Caledonian Canal, it also traverses some of its most iconic landscape. The challenge in upgrading one of northern Scotland’s oldest serving high-voltage lines was therefore not just to deliver the required increase in capacity to meet the grid’s present and future needs but to do so while minimising costs and above all impact on local communities and the environment.

No easy task. Following steep and at times inaccessible terrain along the entire route, the line also crosses a myriad of major roads, railway lines and waterways. The cost and disruption resulting from replacing towers along the route meant that a more creative solution had to be found that would deliver the required boost in capacity without reconstruct or divert the existing line.

A lightweight, high-capacity composite core conductor

And that is precisely where Lamifil comes in. Its wide range of next-generation conductors are renowned for delivering significant improvements in efficiency and load bearing capacity with equally significant reductions in load loss, weight and sag. To meet the highly challenging constraints of the SSEN project, Lamifil supplied over 134 km of advanced ACCC® Monte Carlo ULS conductor. Made from a special aluminium alloy with a carbon composite core, the new conductor provides double the tensile strength and double the load capacity at just 70% of the weight of the original steel conductor.

Enabling an efficient, reliable and sustainable power network

Lamifil’s lightweight conductor solution not only enabled an impressive 100% increase in capacity on the line, it meant that in so doing only 5 of the 156 towers along the route needed to be replaced. The other 151 were reinforced to extend their current lifespan, thereby eliminating the need to purchase new sites for towers and/or plot a new route for the 132,000 volt line; both of which would have meant a very different proposition in terms of cost, timing, planning and social/environmental impact.

As it happened, the disruption to local communities and industries was kept to a strict minimum. A comprehensive emergency return to service plan and special installation methods pioneered by Lamifil guaranteed continuity of supply during the 2-year project. At the same time, extensive scaffolding, safety nets and an innovative catenary support system protected underlying roadways and other infrastructure and allowed for seamless installation with virtually no road, rail or canal closures.

Pat Howe, Lead Project Manager, SSEN Transmission: “At the outset of the project we couldn’t have imagined we would have been able to retain so much of the existing infrastructure as well as doubling the capacity of the line. Our first priority is always to safely deliver a robust, efficient and reliable network to our customers in the most sustainable way. In delivering this essential service, we have demonstrated that this is achievable, even on a project that contained as many challenges as this one. This project has embraced safety, innovation and sustainability, whilst striving to have a positive impact on the communities we have had the privilege of working in. We have set a high standard of how future projects should be delivered.”

Given what was at stake in this landmark project, it is little wonder it was awarded the Capital Project of the Year Award 2020 by the industry benchmark Utility Week. And with the efficiency and longevity of the line secured, the road ahead is clear for even more growth in renewable energy in support of the transition towards net zero emissions.

Pat Howe: “The key to the success of this highly challenging project was the exceptional teamwork right across everyone in SSEN Transmission and all our contractor partners. This highly coveted award is therefore the perfect way for that to have been formally recognised and marks this project’s successful completion.”


ACCC® is a registered trademark of CTC Global Corporation in the U.S. and/or other countries.
ACCC® Conductors are manufactured under license from CTC Global Corporation, in accordance with its technical requirements and specifications.