Innovation puts connections in pole position

Scottish and Southern Electricity Networks (SSEN) and Balfour Beatty have successfully energised the connection for Dorenell Wind Farm in Moray, adding a further 220 MW of renewable energy capacity to the GB transmission system.

In a UK transmission system first, recyclable composite poles were used to in place of conventional steel towers or wooden poles to greatly reduce the impact on the land and minimise disturbance to the local environment and community.

As the transmission owner for the north of Scotland, SSEN is responsible for providing connections to its transmission network for generators looking to export to the national grid.  When planning the connection for Dorenell Wind Farm SSEN had to overcome various challenges to meet the grid connection date required for its generation customer.

The local community were opposed to the use of conventional steel towers due to the cumulative impact in the local area and local landowners opposed the alterative conventional infrastructure of twin trident overhead wooden poles, due to the footprint this would have on their land.

To overcome these challenges and maintain the grid connection date for the wind farm, SSEN and Balfour Beatty developed an innovative solution using composite poles which had less impact on the land, both physically and visually. 

The poles were pre-constructed in a purpose-built assembly yard which improved efficiencies, safety and quality control and crucially, allowed each pole to be flown into position by a specialist helicopter to help meet the tight timescales for the grid connection date.

All 140 composite poles required for the grid connection were safely and successfully installed in just five days, far quicker than conventional crane installation methods would have taken.

This innovative technology - which is already being used successfully in Canada, the USA, Scandinavia and Ireland - uses a durable composite polymer instead of the traditional timber and was specially adapted to meet the unique terrain and environment of the north east of Scotland, eliminating the need to harvest trees, reducing greenhouse gas emissions, carbon consumption, and the degradation of ecosystems.  Composite poles also have a longer lifespan and can be repurposed or recycled.

SSEN’s Lead Project Manager, Paul Higginbotham, said:  “We are delighted we have delivered the successful energisation of the Dorenell wind farm connection on time, ready for our generation customer to start exporting to the National Grid. 

 “Despite being faced with a number of significant challenges to overcome, the innovative solution we developed with Balfour Beatty has ensured that we met the needs of our customer as we continue to enable the transition to a low carbon economy through the decarbonisation of the electricity system in the north of Scotland.

 “The successful deployment of composite poles on our network is also an exciting development which we will now be considering for future grid connections and network reinforcements.”

Andy Smith Operations Director for Balfour Beatty’s Power Transmission and Distribution business in Scotland added:  “Working in collaboration with SSEN, Balfour Beatty identified and developed a truly innovative infrastructure solution that ensured the safe and efficient energisation of the Dorenell wind farm.

“The use of a specialist air crane helicopter and durable composite plastic poles, allowed the Balfour Beatty construction team to overcome the rugged terrain in North East Scotland whilst minimising disturbance to the environment and community.”

The impact on the land was also massively reduced, removing the need for significant access tracks that would normally be required to provide this type of grid connection.

As well as meeting the primary objective of maintaining the grid connection date for SSEN’s generation customer, composite poles also provide a number of benefits compared to more traditional forms of network infrastructure.