Leading cablemaker Nexan has won a contract worth approximately 100 million Euros to design, manufacture and supply the high voltage (HV) subsea power export cables that will connect the London Array wind farm to the UK grid. The contract was placed with Nexans by the consortium of DONG Energy, E.ON and Masdar, which is currently building London Array, which will be the world’s largest offshore wind farm when it comes on line in 2012, in the Thames Estuary. The 128 million Euro contract to supply the grid connection has gone to Siemens Energy, the same company that is supplying the wind turbines.
London Array is being installed on a 233 sq km site located 20 km off the UK’s Essex and Kent coastline. Construction is taking place in two phases: the first phase of 630 MW, consisting of 175 turbines, is expected to be completed and generating in 2012; the future second phase will add capacity to bring the total to 1000 MW, the first in the 1 GW class..
The power export cable contract comprises the design, manufacture and supply of four 150 kV XLPE submarine power cables to be laid in parallel, each 53 to 54 km in length, with three copper core conductors with a cross-section of 630 sq mm for the main length and 800 sq mm each cable end. Nexans will deliver two of the cables in 2011, and two in 2012, all being delivered in single continuous lengths from its factory in Halden. The cables will also incorporate fibre optic elements manufactured at the Nexans factory in Rognan, Norway. In addition, the contract also includes the cable accessories such as repair joints and terminations.
“World-leading schemes such as London Array demonstrate why the UK is currently regarded as one of the pace-setters in offshore wind energy, and we are very proud to be co-operating in this prestigious project with some of the key developers in this dynamic market”, says Frédéric Vincent, Nexans CEO.
Siemens will supply the electrical equipment for two offshore substation platforms to be located at the wind farm site to bundle the power generated by the 175 turbines before it is transported via high-voltage subsea cable to the mainland. On each of the platforms there are two 180 MVA transformers and medium-voltage switchgear.