Scottish and Southern Electricity Networks (SSEN) has submitted a final needs case to Ofgem for a new 600MW subsea transmission link connecting the Shetland Islands to the mainland power grid.
The power system for the archipelago currently operates as an islanded network, with all electricity needs being met by local generation.
As a result, there is no spare capacity to connect new generation on the islands or export the output to the energy market in Great Britain.
SSEN said there is now an opportunity to proceed with the upgrade after the government confirmed in June that onshore wind projects on remote islands will be able to compete in the next contracts for difference (CfD) auction in May 2019.
The cable would run from Kergord on the largest of the islands to Caithness on the Scottish mainland, connecting to the new Caithness-Moray transmission link which is currently under construction.
SSEN director of transmission Dave Gardner said: “We believe our proposal represents a robust, economic case for reinforcement and provides the best possible opportunity to unlock Shetland’s renewable potential.
“The submission marks an important first step in the process, however successful delivery will be dependent on sufficient volumes of renewable generation capacity securing a CfD contract to underpin the investment case, in addition to regulatory approval and relevant planning consents.”
Last year, Ofgem rejected plans for a smaller 60MW cable linking the Shetlands to the mainland following a delay to the introduction of new EU emissions limits that would have otherwise forced the closure of the islands’ diesel power station by 2021.