London Array wind farm off the Thanet coast

by business editor Trevor Sturgess

London Array offshore wind farm is expected to power 500,000 homes after its 175th turbine became operational at the weekend.

Full capacity has now been reached at the 630MW first phase of the world's largest offshore wind farm 12 miles off the Thanet coast. The final turbine in the first phase was commissioned at 4.09pm on Saturday.

All turbines are now exporting power to the National Grid through a sub-station at Graveney, near Faversham, with an estimated cut in CO2 emissions of more than 900,000 tonnes a year. A proposed second phase could boost total capacity to 870MW.

Installation of all 175 3.6MW Siemens turbines was completed in December.

"This is the final major milestone of the construction phase and the culmination of more than two years’ offshore construction work which began in March 2011 with the installation of the first foundation," said project director Richard Rigg.

"It has been a complex operation but I am delighted that the commissioning of the wind farm has now been completed on schedule, despite the worst of the winter weather."

London Array, which is being handed over to an operations and maintenance team, has been completed in the face of tough weather, sea and sub-sea conditions.

It is backed by a consortium of DONG Energy (50%), E.ON UK (30%) and Masdar (20%). Benj Sykes, country manager for DONG Energy’s UK Wind business, said the company was determined to drive down costs of offshore wind farms £85 per megawatt hour. "What we have learnt at London Array, together with our continuing focus on innovation in technologies and techniques, will help us achieve that."