Thanet

Thanet Offshore Wind Farm Profile

Location and Geography

• The Thanet Offshore Wind Farm is located approximately 11.3 kilometers offshore from Foreness Point, the easternmost part of the Kent coastline in the UK.
• The site is in water depths ranging from 20 to 25 meters.

Ownership and Development

• The wind farm is owned by Vattenfall, a Swedish multinational power company, which acquired the rights to the project from Christofferson, Robb & Co (CRC) in November 2008 for $55 million.
• The project was initially conceived by Warwick Energy under the Round 2 offshore wind farm licence applications in 2003. CRC purchased the project in 2007, and Warwick Energy continued to manage it until Vattenfall took over.

Capacity and Turbines

• The Thanet Offshore Wind Farm has an installed capacity of 300 MW, generated by 100 Vestas V90 wind turbines, each with a rated capacity of 3 MW.
• The turbines are spread over an area of 35 square kilometers, with a distance of 500 meters between turbines along the rows and 800 meters between the columns.
• Each turbine stands up to 115 meters tall, with a minimum clearance above sea level of 22 meters.

Infrastructure and Technology

• The turbines are installed on monopile foundations, supplied by Dillinger Hütte, with a diameter of up to 5 meters. The monopiles and transition pieces were delivered by Dutch firms SIF and Smulders, respectively.
• The wind turbines are interconnected by a subsea 33kV cable network, which connects to an offshore substation platform where the voltage is stepped up to 132kV. Two 132kV export cables transport the electricity to the onshore substation at Richborough, near Ramsgate.
• The offshore substation is equipped with two 180MVA power transformers supplied by Siemens Energy. The substation also features high-voltage and medium-voltage switchgear with necessary protection and control technology.

Construction and Timeline

• Construction of the project began in January 2008 and was completed in September 2010, with an estimated cost of £780-900 million (US$1.2-1.4 billion).
• The wind farm was officially opened on 23 September 2010, making it the world's largest operational offshore wind farm at the time of its commissioning.

Operations and Maintenance

• The wind farm is designed to have an operational life of 40 years.
• Maintenance of the turbines is carried out by Vestas, while a separate maintenance agreement with SLP Energy covers the turbine foundations. The turbines were installed by the Danish offshore wind farm services provider A2SEA.
• An onshore maintenance facility, constructed by local building contractor W.W. Martin, supports the operations and maintenance of the wind farm.

Energy Production and Impact

• The Thanet Offshore Wind Farm is capable of powering approximately 240,000 British households annually with clean energy, generating around 960 GWh of electricity per year.
• Along with Vattenfall's other two operational offshore wind farms in Kent, Kentish Flats and Kentish Flats Extension, the three farms combined produce enough electricity to power over 400,000 UK homes annually.

Extension Plans

• There were plans to extend the Thanet Wind Farm, which would have added up to 340 MW of capacity and powered an additional 282,000 UK homes. However, the proposal was rejected by the UK Secretary of State for Business, Energy, and Industrial Strategy in June 2020 due to concerns about marine navigation.

Contractors and Suppliers

• Turbines: Supplied by Vestas.
• Foundation Design: Ramboll was responsible for the detailed design of the wind turbine foundations.
• Monopiles and Transition Pieces: Supplied by Dillinger Hütte, SIF, and Smulders.
• Underwater Cable Installations: Carried out by Subocean.
• Project Management: Provided by Noble Denton.
• Grid Connection: Siemens Energy and Prysmian Cables & Systems were involved in connecting the wind farm to the British power grid.

Additional Information

• The wind farm was one of the 15 Round 2 wind projects initiated by the Crown Estate, announced in January 2004.
• The project features a shore-based maintenance facility with energy-saving measures such as solar panels for heating water and rainwater harvesting.