Energy / Marine surveys set to get underway for second HVDC cable
SURVEY work for the design and potential route of a proposed second power cable between Shetland and the Scottish mainland will take place over the coming months.
The marine surveys, to be carried out by Reach Subsea, will gather information on seabed morphology and sediment structure, while it will gain benthic characterisation and habitat mapping.
Areas due to be surveyed include to the south west and west of Shetland.
An SSEN Transmission spokesperson said: “Starting this month and continuing through to summer 2026, our contractors will carry out detailed survey work between Shetland and the Aberdeenshire coast.
“These surveys are a routine early step that help us understand the seabed and wider marine environment, and will inform the design and potential route of the subsea cable for the proposed Shetland 2 HVDC Link.
“This follows on from the information shared during last year’s public consultation.”
A survey vessel is in Shetland at the moment to complete monitoring of the existing HVDC (High Voltage Direct Current) cable, which runs from Caithness into Weisdale Voe and has a capacity of 600MW.
This subsea cable allows power from the Viking wind farm to be exported to the national grid, and it will also enable power to come up to Shetland from the mainland.
Once Lerwick Power Station goes into standby mode – expected later this year – Shetland as a whole will be connected to the national grid via the cable.
But with more energy developments on the horizon, a second HVDC link – with a capacity of 1.8GW – has been proposed by SSEN.
As well as helping enable the connection of two proposed offshore wind farms east of Shetland, which have a combined generating capacity of up to 2.8GW, SSEN Transmission said the “Shetland 2” cable will also “support decarbonisation and energy security ambitions, alongside helping further secure Shetland’s future electricity needs”.
The plan is to connect the second HVDC link to a proposed new northern substation hub facility in the Sullom Voe or Scatsta area.
SSEN has a few landfall sites in Shetland under consideration for the second cable, including Wethertsa and Toft Ness.
The energy company’s timeline shows that construction could begin post-2028, with an aim to have the cable live in 2035.
It is not just a cable that is involved; at both ends of the link there would be a need for new HVDC converter stations, while a new AC substation would required in Shetland too.
There are also proposals to run large ‘pylons’ from Kergord to near Sullom Voe Terminal, to connect to the new northern substation hub.
These overhead lines have proved particularly controversial and were the subject of a recent petition created by residents of Voe.
Become a member of Shetland News
Shetland News is asking its readers to consider paying for membership to get additional perks:
- Removal of third-party ads;
- Bookmark posts to read later;
- Exclusive curated weekly newsletter;
- Hide membership messages;
- Comments open for discussion.
If you appreciate what we do and feel strongly about impartial local journalism, then please become a member of Shetland News by either making a single payment, or setting up a monthly, quarterly or yearly subscription.
Already a member? Sign in to hide this message.
