by business editor Trevor Sturgess

Developers of the world’s largest offshore wind farm off Thanet are bidding to expand the project after assurances that rare seabirds will not be affected.

London Array has announced today that it has submitted a proposal to the Department of Energy Climate Change (DECC) and the Marine Management Organisation (MMO) to allow the second phase to go ahead.

It could add a further 65 wind turbines to the 175 in phase 1, although the number could be lower if the larger 6MW turbine is used.

The new phase would cover an area of 40sq km along the eastern boundary of the existing phase, which is due for completion by the end of the year.

It could generate enough renewable energy to meet the annual electricity needs for more than 180,000 homes.

But planning permission has been held up until investigations into its potential impact on red throated divers that flock to the special protected area in winter.

Following surveys by Natural England and the RSPB bird charity, London Array says it is now happy to go ahead with the second phase, although it will be slightly smaller than the original proposal.

Richard Rigg, project director, said: “Since receiving its original consent in 2006, London Array has been working alongside Natural England and the RSPB to collect, analyse and review information on the Red Throated Divers that winter in the Thames Estuary.

“The proposal for Phase 2 is based on the results of these monitoring and modelling studies and envisages a scheme of up to 240MW.

"London Array believes the proposed scheme, which uses only part of the area available for Phase 2, can maintain the integrity of the Special Protected Area in which the wind farm sits and will not adversely affect the population of Red Throated Divers.”

Both phases, together rated up to 870MW, would generate enough electricity for 650,000 homes.

A consortium comprising Danish firm DONG Energy (50%), E.ON (30%) and Madsdar (20%), is behind London Array. The first phase is costing £1.76bn.