The British energy regulator Ofgem has rejected plans by Scottish and Southern Energy Networks (SSEN) to build two 600 MW HVDC transmission lines between the Shetland, the Western Isles and mainland Scotland (United Kingdom). The Ofgem has invited SSEN to submit revised proposals for both transmission links.
The first 600 MW power line project between the Shetland Islands and mainland Scotland was based on the development of the 412 - 457 MW Viking Energy Wind Farm project, which failed to win a Contract for Difference (CfD) in recent government auction. The regulator thus considered that there were risks for consumers of paying for an underutilised transmission link to the Shetland Isles. The Shetland link project was expected to break ground in 2020 and to be commissioned in 2024 at a total cost of £649m (€750m). It would have connected into the Caithness-Moray transmission line that is currently under construction. The Shetland Islands are currently not connected to the main Great Britain transmission system and operate as an island network, while local needs are met from local power generation. There is no new available capacity to connect new power generation on the islands and a link to the mainland would be required to enable the development of future renewable projects.
The Ofgem also rejected SSEN's proposal to build a 600 MW transmission line to connect the Western Isles to mainland Scotland, which was based on two large wind projects (Stornoway and Uisenis, previously known as Lewis Wind Power projects), since only Uisenis wind project secured a CfD in the auction of September 2019 and is more likely to be developed.