June 2021
Stronelairg Wind Farm:
Promat systems enhance fire safety at one of SSE’s windiest renewable energy sites
Key points
- Sector: Renewable energy
- Products: DURASTEEL®, VERMICULUX®
- Client: SSE Energy Services
- Architect: Jones Lang LaSalle
- Contractor: BAM Nuttall
- Subcontractor: The Invicta Group
- Project duration: Nine weeks
Project overview
As a leading provider of renewable energy across the UK, SSE Energy Services aims to drive the transition to a net zero carbon world through the development, construction and operation of state-of-the-art renewable energy assets. To support this mission, in 2017 SSE built a wind farm in Stronelairg - a remote area of Scotland near Loch Ness. At an elevation of around 600 meters above sea level, it is one of SSE’s windiest sites. The site includes 66 wind turbines and has the capacity to generate 228 MW of energy.
As part of the project, SSE needed to create three transformer enclosure bays on the site, each of which had to meet a demanding four-hour fire-rated standard. This required the installation of walls and ceilings - as well as internal access doors for maintenance personal - that would all meet this high-level of fire resistance. It was also necessary that various penetrations, including wall bushings, were able to safely pass through the barriers in the enclosure bays.
An additional challenge was that the project would have to be completed in an isolated setting where the work would be constantly exposed to cold, wet weather conditions.
Having worked with Promat and its products for more than a decade, the project’s subcontractor, Invicta, knew its fire protection solutions would be a perfect fit for the wind farm’s unique requirements.
Design and specification
Invicta and independent structural engineers designed a bespoke 1800m² wall and ceiling system consisting of Promat’s DURASTEEL® and VERMICULUX® boards.
Promat DURASTEEL® is a high impact, blast and fire-resistant system that provides up to 240 minutes integrity rating from fire attack from either side, meaning that a fully developed fire would not be able to pass through one side of the wall to the other for a period of four hours. The bespoke solution designed and constructed by Invicta was based on standard single skin, integrity-only DURASTEEL® wall and ceiling systems, tested and Certified by Promat.
At the Stronelairg site, the DURASTEEL® system was accommodated within the transformer enclosure bays’ structural steel construct in order to give it stability in the event of a fire. The solution means that even if there’s a fire, the power station can keep running as the other transformers won’t be affected, which is crucial when it comes to such an important piece of national energy infrastructure.
Installation
The main installation challenge with this project was that it was based at an altitude of more than 3000m, meaning that site delivery and access points were extremely difficult to get to. The site’s isolated location meant that getting to the project’s access point required driving ten miles up a man-made service road and then travelling a further five miles to base camp and then an additional five miles to the working platform.
The altitude and geography also meant that any solution would have to be constructed and able to fully function whilst facing extreme climate conditions; such as temperatures of -10°C, high winds and heavy snow. It was necessary to be able to carry on with construction in these extreme conditions to complete on schedule. DURASTEEL® lent itself well to both of these challenges because as a board product it can be easily transported and installed onsite, plus its modular application nature ensures speedy application.
Specialist all-terrain access equipment was required to overcome the challenging site conditions and safely construct the system. The walls themselves had to be erected without the main roof being in position and during both high winds and heavy snow. Thankfully, because the products used could be easily constructed in small, lightweight components with no lifting equipment required, they were suitable for installation even in such difficult working conditions. In addition, as the DURASTEEL® product is screwed and bolted together there’s no requirement for cement/mortar, meaning that the cold weather wasn’t an issue.
The programmed time for installation was 12 weeks, with seven Invicta DURASTEEL® installation engineers on-site at any one time.
Final Results
Despite working in extremely harsh conditions, which required a blend of different requirements, the unique project was completed by Invicta within nine weeks – three weeks ahead of schedule. Upon completion of the project, Invicta presented a full handover to SSE, which included third-party certification of the DURASTEEL® barriers, ceilings, doors and fire seals, confirming that the project was completed to the required standards. As part of this, one of Promat’s technical support technicians attended the site to inspect and provide a Certificate of Conformity for the installation.
Using Promat’s solutions, the site’s fire safety was enhanced significantly, which not only provided peace of mind to the client, but also ensured the power station would be able to keep running in the event of a fire in one of the transformers. Not many wall and ceiling systems are able to provide a four-hour fire rating, which is a demanding requirement, typically only found in high-risk industrial settings such as the power industry. The project also showcased how effectively Promat’s specialist solutions and products could slot into large, unique and complex installations.
Benn Larkin, sales manager at Invicta, said:
“Invicta Durasteel are proud to be the worldwide market leaders as a Durasteel licensed installer in partnership with Promat, committed to install fire protection solutions to the highest standard, complete with certification in all Durasteel sectors including ventilation. The Durasteel solution was ideal for this project, as it offered complete compartmentation acting as fire enclosures, protecting each transformer from the adjacent transformer and was designed to offer cable support where required. Service openings were formed for passing wall bushings to distribute power throughout the building. As well as protecting the transformers, this solution also protects the rest of the building facility, which is a reactor hall substation area.”
