Collett & Sons has transported two 160-tonne shunt reactors over 5,000 miles (8,000 km) to the onshore substation site for the Neart na Gaoithe (NnG) offshore wind farm project.
Collett was contracted to provide a door-to-door service, including the project management, engineering and the transport of the two reactors.
A year before deliveries commenced, Collett’s consulting department undertook multiple surveys to find the most feasible route, including swept path analysis reports, topographical surveys, bridge height surveys and wire cable height surveys. This resulted in Collett temporarily removing street furniture and employing tree surgeons to remove obstructing foliage.
The shunt reactors were transported in three stages before arriving at the substation site. First, Collett worked with a European partner to arrange the delivery to the port of Leith in Scotland, including the chartering of a suitable vessel.
Once at the port, Collett utilised an 800-tonne capacity crane to discharge the units onto a dedicated 14-axle line modular flat top trailer. Both shunt reactors were then offloaded onto stools for temporary storage. Collett also transported and stored multiple ancillary components at its port side depot in Grangemouth.
Utilising its 550-tonne capacity girder bridge with 20-axle lines, Collett transported the shunt reactors from Leith Docks to Innerwick. Due to narrow access along the remainder of the route, Collett transhipped each of the reactors from the 20-axle girder bridge on to a 14-axle flat top modular trailer in a dedicated road closure area.
At the onshore substation site, located in the Lammermuir Hills, Collett’s heavy lift team offloaded and positioned the shunt reactors into their final position using a hydraulic jacking and skidding system.
The second part of the project is expected to take place in the coming weeks, when two 180-tonne supergrid transformers are due to be delivered to the site.