Westermost Rough

Location and Overview

The Westermost Rough Offshore Wind Farm is located approximately 8 kilometers northeast of Withernsea, off the Holderness coast in the North Sea, England, UK. It is situated about 25 kilometers north of Spurn Head at the River Humber estuary.

Capacity and Turbines

The wind farm has a total installed capacity of 210 MW, generated by 35 Siemens SWT-6.0-154 wind turbines. Each turbine has a capacity of 6 MW and features a rotor diameter of 154 meters, with blade lengths of 75 meters, which are among the longest in the world.

Ownership and Development

The project was developed by DONG Energy (now known as Ørsted) through its subsidiary Westermost Rough Ltd. The ownership is shared among several entities: Ørsted UK (50%), Arjun Infrastructure Partners (25%), Equitix (12.5%), Universities Superannuation Scheme (9.37%), and StepStone Group (3.12%).

History

• The site was originally awarded to Total in 2003 but was returned to the Crown Estate in 2006 after Total withdrew.
• In 2007, DONG Energy was awarded a lease to develop the wind farm.
• A planning application was submitted in November 2009, and consent was granted by the Department of Energy and Climate Change in 2011.
• Construction began in January 2014, and the wind farm became operational in May 2015.

Construction and Infrastructure

• The wind farm covers an area of approximately 35 km² (14 sq mi).
• The turbines are installed on monopile foundations, each with a diameter of 6.25 meters and a mass of up to 800 tons. The foundations were installed by GeoSea.
• The offshore substation was designed by Ramboll, and the medium voltage cables were supplied by Nexans. High voltage submarine export cables were supplied by LS Cable & System of Korea.
• The power generated is transmitted to the offshore substation via a 33kV inter-array cabling system and then stepped up to high voltage before being transmitted ashore via a submarine cable. The cable lands near Tunstall and continues underground to a new substation at Salt End.

Environmental Impact and Benefits

• The wind farm contributes significantly to the UK's renewable energy targets and helps reduce greenhouse gas emissions. It is estimated to offset approximately 264,429 tons of CO₂ emissions annually.
• The project underwent extensive environmental impact assessments to ensure minimal disturbance to the physical, biological, and human environments. The assessments considered the impacts during construction, operation, and decommissioning phases.

Operations and Maintenance

• The wind farm was commissioned and became operational in May 2015.
• Siemens Gamesa Renewable Energy is responsible for the operation and maintenance of the turbines, with a contract that includes remote monitoring and diagnostics, as well as service technicians accessing the turbines via helicopters.
• CWind was awarded a 20-year contract to maintain the electrical transmission assets of the wind farm.

Power Generation and Impact

• The wind farm generates approximately 800,000 MWh of electricity annually, which is enough to power more than 150,000 British households.
• The project is part of the UK's goal to install 33 GW of offshore wind power by 2020 and contributes to the country's target of achieving 15% of its energy from renewable sources by 2020.

Financial and Investment Details

• The project was funded through a joint investment by DONG Energy, Marubeni Corporation, and the UK Green Investment Bank. The total investment was £800 million (approximately $1.37 billion).
• In August 2014, the joint venture secured £370 million from lenders to fund the capital costs of the project.

The Westermost Rough Offshore Wind Farm is a significant project in the UK's offshore wind sector, marking several milestones including the first commercial use of Siemens' 6 MW direct-drive wind turbines with 154-meter rotor diameters. It plays a crucial role in reducing carbon emissions and contributing to the UK's renewable energy goals.