The Viking wind project under construction on the Shetland Island, Scotland will be the biggest onshore wind farm in the UK with a net power output of 443MW.

The onshore wind farm is being developed by Viking Energy Wind Farm, a joint venture between SSE Renewables and the Shetland community.

SSE Renewables announced a final investment decision (FID) for the £580m ($732m) project in June 2020 which was followed by the award of construction and turbine supply contracts.

The preparatory construction works for the project were started in August 2020, while the wind farm is expected to commence partial operations in the first quarter of 2023 and achieve full capacity by 2024.

The 443MW onshore wind farm will be capable of generating approximately 2TWh of electricity to power up to 500,000 UK homes while offsetting half a million tonnes of carbon dioxide (CO2) emissions each year.

Location and site details

The Viking onshore wind farm is being built in central Mainland Shetland, Scotland, UK, in the Northern Atlantic.

The wind farm site is being connected through new access tracks off the main road A970.

A temporary main construction compound for the wind farm is being built on a 250m2-site southeast of Sandwater.

Viking onshore wind farm make-up

The Viking onshore farm will be installed with 103 Vestas V117-4.2 wind turbines with an optimised power output of 4.3MW each.

Designed to endure extreme wind conditions, the V117-4.2 onshore wind turbines come with 57.2m-long blades and large diameter steel towers with a hub height of 91.5m.

With a 117m-diameter rotor, each turbine will have a swept area of 10,751m2. The cut-in and cut-out wind speeds for the turbines will be 3m/s and 25m/s respectively.

Power evacuation through the Shetland HVDC link 

The electricity generated by the Viking onshore wind farm will be fed into the Great Britain power grid through the Shetland Interconnector, which is a high voltage direct current (HVDC) link being developed by SSE to transmit 600MW of renewable electricity between the Shetland Isle and the mainland Scotland.

Ofgem, the regulatory body for the electricity and natural gas markets in Great Britain, approved the Shetland HVDC interconnector project in July 2020.   

Contractors involved 

Vestas was awarded the contract to supply 103 units of V117-4.2 wind turbines for the Viking onshore wind power project in August 2020. The scope of the contract also involves a service agreement for a period of 30 years.

RJ McLeod, a Scottish civil engineering contractor, was awarded the main construction contract for the Viking onshore wind farm in July 2020. The scope of the contract also includes the construction of the new Sandwater road along with the network of access tracks, the erection of construction compounds, as well as the bases and crane pads for the turbines.

Tulloch Developments was awarded a contract for the construction of an access track at the wind farm site in February 2020.

BAM Ritchies and Tony Gee partners were contracted for the ground investigation work of the Viking Onshore wind farm project in 2019.

Shetland Windfarm Environmental Advisory Group (SWEAG) is responsible to oversee the monitoring measures of the conservation programme and the habitat management plan (HMP) for the wind farm project.

Viking Onshore wind farm project background 

The Shetland community and SSE Renewables signed a partnership deal for the construction of the Viking Onshore wind farm in 2007.

While an application for the development of the wind farm with 150 turbines was originally submitted to the Scottish government in May 2009, a revised application was submitted in September 2010 reducing the number of turbines to 127.

The Scottish Ministers granted permission for 103 wind turbines excluding 24 turbines adjacent to Scatsta Airport in April 2012.

A revised application was approved to increase the maximum tip height of the turbines from 145m to 155m and the hub height from 90m to 95m in May 2019.

In July 2020, Viking Energy signed a deal with the Shetland Community Benefit Fund (SCBF) to contribute £400,000 a year during the construction phase starting from August and approximately £2.2m a year during operations over an estimated project life of 25 years.