SSEN Transmission Proposes New HVDC Converter Station

SSEN Transmission is seeking input on it proposals to build a new HVDC Convertor Station and 132kV substation at Arnish on the Isle of Lewis, with a public information event in Stornoway.

The substation is a critical part of wider plans to construct a new 600MW HVDC subsea transmission link to connect the Western Isles to the GB transmission system

The Western Isles is home to some of Scotland's greatest wind resource and following the growth in small-scale renewable electricity generation, the existing Western Isles electricity network is at full capacity meaning no further generation can connect without significant network reinforcements.

SSEN Transmission is proposing to construct a 600MW High Voltage Direct Current (HVDC) subsea cable link from Arnish on the Isle of Lewis to Dundonnell on the Scottish mainland, before continuing underground to a new HVDC Converter Station on the mainland and subsequently connecting to the existing transmission system. The link will be designed to transmit power in both directions and is key to enabling the connection and export of renewable electricity to the GB transmission network. Progression of the project, which currently has an energisation date of March 2027, remains subject to developer commitment and Ofgem approval.


As part of the proposals, SSEN Transmission is intending to submit a planning application to Comhairle nan Eilean Siar for a new HVDC Converter Station and Gas Insulated Substation (GIS) at Arnish Point near Stornoway. The public exhibition later this month is an opportunity to find out further details about the project and for members of the public to share their views on the proposals for the new development at Arnish.

The in-person exhibition will take place at Caberfeidh Hotel in Stornoway on Tuesday 21 June, between 3pm and 7pm, and will be hosted by the SSEN Transmission project team. The event is an open-door drop-in session for anyone interested in learning more about the project.

SSEN Transmission Project Manager David Williams said:

"The public exhibition next month is a chance for the local community and wider stakeholders to share their views on our proposals to build a new substation development at Arnish, which will play a key role in the  proposed Western Isles subsea HVDC link.

"We are committed to working with the local community as we continue to develop our proposals and we would encourage anyone who is interested in finding out more about our plans to drop in to our public exhibition in Stornoway to learn more."