Plans by SSE PLC to build a wind farm with up to 457 MW of capacity on the Shetland archipelago in Scotland are facing headwinds as environmental groups and the U.K.'s defense ministry, among others, are opposing a proposal to increase the size of the turbines used in the project.
The Viking wind farm, which SSE hopes to secure a government subsidy contract for this year and bring online by 2024, is being developed in a joint venture with the Shetland Charitable Trust. In November of last year, the developers applied to modify their plans by replacing the 3.6-MW turbines with higher and more powerful 4-MW machines, after the original proposal had survived a court challenge fought between 2012 and 2015.
This would lift the project's maximum output from approximately 370 MW closer to its consented capacity of 457 MW and make it the third-largest wind farm in the U.K., according to SSE.
But the proposal has attracted a long list of objections and now the John Muir Trust, a conservation charity, is calling for a public inquiry into the plans to resolve environmental and landscape concerns as well as other issues raised in public comments against the plans, including from local community councils and the Scottish Environment Protection Agency.
"An inquiry seems like the fair way for local people to have their say," said Helen McDade, the trust's head of policy, noting that objections from a local planning authority or significant concerns raised by other stakeholders could spark the government to launch a deeper probe.
"[The application] is one of many recent Scottish applications for increased wind turbine heights on sites which have previously been given consent for smaller turbines, which have not yet been built," McDade added.
The Defense Infrastructure Organization, an arm of the U.K.'s Ministry of Defense, has also appealed to Scotland's Energy Consents Unit, which has to approve wind farms above 50 MW, to deny the revised plans.
In a letter to the authority on Nov. 27, 2018, Teena Oulaghan, a safeguarding officer at the ministry, wrote that the 155-meter turbines — 10 meters higher than currently approved — "will cause unacceptable interference" to air defense radar at a Royal Air Force station on the island of Unst.
A spokesperson for Viking Energy, the joint-venture company owned 50% by SSE, said objections like the defense ministry's were common for wind projects and that a decision on the planning application was expected in the coming months.
Viking wants to start construction of the wind farm in 2020 and SSE is separately seeking to build a 600-MW subsea interconnector from Shetland to the Scottish mainland to export excess renewable electricity from the island archipelago.
Onshore wind farms on remote islands will for the first time be allowed to compete with offshore wind projects under the government's next Contract for Difference auction, to be held by May this year. Onshore wind projects stand to receive long-term contracts with a guaranteed strike price of up to £82/MWh, according to the government's plans.