The Greater Gabbard development, excluding connection to the electricity grid, is expected to need investment of £1.3bn.
The site is located 25km off the cost of Suffolk and will consist of 140 wind turbines installed in water depths of between 24 and 34 metres. When completed its total capacity is expected to be 500MW. npower renewables and SSE will share the electricity output 50-50 when the wind farm construction is completed in 2011.
RWE Innogy is aiming to increase its renewables production capacity to 4,500 MW by 2012.
Ian Marchant, Chief Executive of SSE, said:
“I am pleased that RWE Innogy will be our partner in this joint venture. Its long-standing interest and participation in offshore wind farm developments will complement our own expertise in the development of major renewable energy projects.”