Beatrice Offshore Wind Farm

Beatrice offshore wind farm is a 588MW offshore wind project to be located in Northern Scotland. Image: courtesy of SSE.

Beatrice will be the first project to be equipped with Siemens' new Offshore Transformer Module (OTM). Image: courtesy of www.siemens.com/press

The offshore wind farm will include an OTM attached to the wind turbine. Image: courtesy of www.siemens.com/press

The Beatrice Offshore Wind Farm will be located on the north-western point of Smith Bank in the Outer Moray Firth, Scotland, approximately 13.5km away from the Caithness coastline.

Covering an area of 131km², the offshore wind farm will be located in close proximity to Beatrice oil platforms and the Jacky oil platform. Upon completion, the project will generate 588MW of renewable electricity, which will be enough to meet the electricity needs of 450,000 UK households.

The project was approved by the Scottish Government in March 2014. Beatrice Offshore Wind Farm Ltd (BOWL), a partnership of SSE (40%), Copenhagen Infrastructure Partners (CIP) (35%) and SDIC Power (25%), will be responsible for the construction.

The offshore construction is expected to begin in 2017 and the wind farm will be commissioned in 2019. The wind farm is expected to employ 890 and 90 people during construction and operational stages respectively.

Beatrice offshore wind farm make-up

The wind farm will be installed with 84 Siemens wind turbines, capable of generating 7MW of power each, with a 154m diameter rotor.

All the wind turbines will be mounted on pre-piled jacket substructures, which will be installed at water depths of 55m. The management, designing, engineering, fabrication and installation of the substructures will be managed by Subsea 7 in collaboration with Seaway Heavy Lifting.

The wind farm will also include Siemens onshore and offshore substations. The offshore substations will include two offshore transformer modules (OTMs), which will be connected together. The OTMs are one-third in size and weight in comparison to conventional alternating-current (AC) platform and, hence, result in cost saving as no special heavy lift vessel is required for installation.

The operations and maintenance base of the wind farm will be located at Wick Harbour. The wind turbines will be serviced and maintained by Siemens for a period of 15 years.

Cable and grid system details of the Beatrice offshore wind farm

A consortium of Siemens Transmission and Distribution and Nexans will provide the transmission system.

Siemens will provide the offshore grid connection, while Nexans will supply two 90km-long 220kV export cable circuits along with 260km onshore and offshore cables, in mid-2016.

Installation and trenching of the cables is expected to begin in late-2017 using the cable laying ship C/S Nexans Skagerrak and its Capjet system respectively. Nexans was awarded a $356.4m contract to undertake the works.

The power produced by the turbines will be transferred to the OTMs with the help of 33kV array cables and will be converted into 220kV by OTMs before being transferred to the onshore substation.

The power will be further stepped up to 400kV at the substation and then transmitted to the grid network.

Financing for the Scottish offshore wind project

The Beatrice offshore wind project will attract an investment of $3.7bn, which is claimed to be one of the biggest private investments in Scottish infrastructure.

European Investment Bank (EIB) supports the investment, with active participation from the new European Fund for Strategic Investments (EFSI).

The project is expected to inject approximately $990m to the UK and Scottish economy.

Power purchase agreements

Danish energy firm, Danske Commodities signed a 15-year power purchase agreement (PPA) with BOWL in January 2016 for buying 294MW electricity, which is equivalent to 50% of the total energy produced by the plant.

Contractors involved with Beatrice offshore wind farm development

Burntisland Fabrications (BiFab) was selected to manufacture of 26 jacket substructures for the Beatrice Offshore Windfarm.

Swire Blue Ocean was awarded a contract by Siemens to supply wind farm installation vessel for the installation of 84 Siemens wind turbines.