Located in Margate, Kent, the 175 wind turbines at the site will be able to generate 630 MegaWatts of electricity, which is enough power for nearly half a million homes, or the equivalent to two-thirds of Kent.

The project was a £1.5bn joint venture by energy companies DONG Energy, E.ON, and Masdar, Abu Dhabi’s state backed renewable energy company, and involved over 75 organisations and 6,700 people to bring it to fruition.

Davey said: “London Array is a big deal for offshore wind, a big deal for UK electricity supply and a big deal for inward investment into the UK.

“It’s a bulk generator of power feeding into the diverse mix on our grid. Half a million homes will be London Array powered. This is good news for keeping our lights on and reducing carbon emissions”.

Davey said that the project has attracted billions of inward investment into the British economy.

“The Government is reforming the market, and last week announced long term support for offshore wind, to make sure that more projects like this come to fruition,” he added.

The PM formally opened the wind farm with a speech in which he welcomed the investment in the UK clean energy sector and called it a “win for local jobs, skills & growth.”

Commenting on the opening of the array, energy and climate change specialist at WWF-UK, Jenny Banks, said: “It’s great that world-leading offshore wind projects like this are being built here in Britain. The UK has Europe’s largest offshore wind resource in the North sea and currently has more offshore wind capacity than any other country in the world.

“The UK is ideally suited to becoming a world leader in this technology with a recent report showing that offshore wind could boost the UK economy by £20bn. It’s important that the government puts the right policies in place to send clear signals to companies like Siemens, which wants to invest in offshore wind manufacturing plant in Hull, that the UK is open for business.”

Marking the inauguration, Siemens, who supplied the 175 wind turbines and the grid connection for the wind farm, said the array will reduce annual CO2 emissions by approximately 900,000 tons, which equals the emissions of 300,000 passenger cars.

Speaking at today’s inauguration, CEO of Siemens AG said: “London Array is the world’s largest offshore wind power plant and marks a milestone in the development of offshore wind power.

“Projects of this magnitude contribute to further industrialization of complex production and logistics processes for offshore wind power plants,” he added.

However, some green groups hit out at the Government, disputing its energy strategy and continued use of gas and oil.

Friends of the Earth’s executive director Andy Atkins said: “London Array is a top class energy scheme Britain can be proud of. The UK has some of the best renewable energy resources in Europe, but Ministers aren’t doing nearly enough to develop this huge potential and create thousands of new jobs.

“David Cameron must end his Government’s support for climate-wrecking gas and oil and get behind a clean energy revolution that puts the long-term future of our economy and environment first.”

The array’s final wind turbine was commissioned in April and marked the culmination of more than two years’ offshore construction work, which began in March 2011.

Leigh Stringer

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