Completion of Caithness-Moray transmission link

Scottish and Southern Electricity Networks Transmission (SSEN Transmission), the wholly-owned subsidiary of SSE plc, has completed the construction, commissioning and energisation of the new Caithness-Moray electricity transmission link.

Caithness-Moray is the largest single investment ever undertaken by the SSE Group and represents the most significant investment in the north of Scotland electricity transmission system since the 1950s.  Total spend for the project will be around £970m* against an allowance of £1,062m, net of £55m of allowance already returned through the Price Control (all in 13/14 prices).

The link uses HVDC (High Voltage Direct Current) technology to transmit power through a 113km subsea cable beneath the Moray Firth seabed between new converter stations at Spittal in Caithness and Blackhillock in Moray.  Constructed over a period of four years, the project also involved work at eight electricity substation sites and has also required two overhead electricity line reinforcement projects.

Completed on time and within the allowance approved by Ofgem, the Caithness-Moray link provides up to 1,200MW of capacity to transmit power from the increasing sources of renewable energy from across the far north of Scotland, demonstrating SSE’s focus as a leading provider of infrastructure to enable the transition to a low carbon economy.

The link has already enabled turbines from Beatrice offshore wind farm (588MW on completion) and Dorenell onshore wind farm (177MW on completion) to connect to the national grid with a further 100MW of onshore generation in Caithness and Ross-shire due to connect in the coming months.

The completion of the link and other electricity transmission projects is expected to help take the Regulatory Asset Value (RAV) of SSEN Transmission to around £3.3bn at 31 March 2019.  In the remaining years of the RIIO-T1 Price Control the business has a pipeline of planned capital investment of around £640m, as at 1 January 2019, meaning it remains on track to increase its RAV to around £3.6bn by March 2021.

Dave Gardner, who led the project as SSEN’s Director of Transmission, said:

“The successful energisation and commissioning of the Caithness-Moray link, on time and within budget, is a significant achievement for SSEN and everyone involved in the project. 

“Caithness-Moray has been a highly complex project, requiring very high standards of project design, development, construction and commissioning.  It has been delivered by a team of committed and skilled people, working closely with contractors and other stakeholders.  It will support deployment of renewable energy in the north of Scotland for many years to come.

“Now an operational asset, we will closely monitor the link and associated infrastructure to ensure its continued success as an integral part of the GB transmission system.

“We would like to thank all those who contributed to the success of the project, from our own teams of engineers and support staff, our supply chain and the local communities who have played host to our project teams over recent years.”