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Tendering for interconnector under way

The proposed inter-connector's route from Kergord to Weisdale Voe. Image: SSEN

SCOTTISH Hydro Electric Transmission has started the tendering process to find a company that could supply and install a 600MW undersea cable to connect Shetland to the UK-wide national grid.

The proposed 260 kilometres long high voltage direct current (HVDC) link would connect the planned converter station at Kergord with the existing transmission system at Noss Head, in Caithness.

Scottish and Southern Energy Networks (SSEN) say that more than 500MW of renewable energy generation currently proposed for Shetland requires a connection to the UK mainland.

The company confirmed on Thursday that it would like to submit a “Needs Case for Shetland” to Ofgem as early as autumn of this year, ahead of finding out what the likely cost of the subsea cable would be.

But awarding the contract depends on whether two local wind farm projects have been successful in their bids for subsidy under the Contract for Difference (CfD) auction. This decision is expected for later in 2019.

The cable tendering process is the latest sign of optimism from within the renewables sector that the controversial Viking Energy wind farm as well as Peel Energy’s Beaw Field project will eventually be built.

Earlier this summer Viking Energy successfully fought off a legal challenge before the Scottish Land Court, while during a visit to the isles in early August Scotland Office minister Lord Duncan said he was almost certain that the subsea cable would be built.

A spokesperson for SSEN said: “We remain committed to taking forward proposals for a transmission link to Shetland in a timely manner, as soon as developer commitment and all necessary regulatory and planning approvals are confirmed.”

Meanwhile, Shetland Islands Council has been lobbying those with a say in these matters to include a last minute specification change to allow the interconnector to also function as a replacement for the Lerwick power station which will have to close by 2025.

SIC chief executive Maggie Sandison added: “We wanted to know from Ofgem that the option appraisal had really focussed on the sustainability for Shetland’s power, but also the potential for Shetland being an energy hub for the future.”

SSEN confirmed on Thursday that the 600MW cable proposed to Ofgem is primarily based on the requirement to export energy from Shetland but will be both, importing and exporting.

“Following Ofgem’s decision to reject the Shetland New Energy Solution in November last year, SSEN’s distribution business is currently exploring further options to ensure long term security of supply on Shetland at the most affordable cost,” the spokesperson said.

“However, the transmission link could help deliver Shetland’s future energy needs, which Ofgem alluded to when they rejected the proposed new energy solution.”

There are currently two Shetland projects on the National Grid’s register for connection: The 412 MW Viking Energy wind farm and Peel Energy’s 72MW project for south Yell. Both projects are expected to be operational by the end of March 2024.

Peel Energy’s 50MW Mossy Field project, between Lerwick and Scalloway is due to come before Shetland Islands Council’s planning board in due course.