First Foundation at London Array Installed by A2SEA’s Seaworker (UK)

DONG Energy, E.ON and Masdar today (8th March) announced that the first of 177 foundations has been installed at the London Array Offshore Wind Farm, in the Thames Estuary.

The monopile, weighing 268 tonnes – the equivalent of around 35 double decker buses – was supplied and installed by joint venture company Per Arsleff Bilfinger Berger Ingeniurbeu GmBH using A2SEA’s jack-up barge, Seaworker. The transition piece was then lifted into place, completing the project’s first full foundation installation.

Anders Eldrup, CEO of DONG Energy, said: “This is a significant milestone for London Array, off the shore and into the water. Soon we’ll be seeing the turbines going up and the wind farm starting to generate low carbon electricity. DONG Energy is proud to be the major shareholder, investing in the UK’s biggest offshore wind farm.”

Dr Frank Mastiaux, Chief Executive of E.ON Climate & Renewables, said: “Installing the first foundation on schedule marks another major milestone in the construction of the world’s largest offshore wind farm. It’s a great moment for the team now that all the detailed and diligent planning and preparation over years can finally be seen out in the water.”

Dr. Sultan Al Jaber, CEO of Masdar, said: “The installation of the first foundation is demonstrative of the commitment and collective desire to make London Array a reality, and is a strong testament to the industry-leading resources and experience exemplified by this strategic partnership. Masdar is proud to be at the heart of this ambitious effort which will not only catalyze the wiread scale-up of offshore wind power, but also act as an important contributor to the economic vision of Abu Dhabi and the governments and companies with whom we are collaborating.”

Each foundation consists of a tubular steel monopile, driven 20 to 50 metres into the seabed, and a large yellow transition piece, which is fixed over the top of the monopile to provide the base for the wind turbine. The monopiles are between 33 and 65 metres long and weigh between 200 to 650 tonnes, while the transition pieces are between 20 to 28 metres high and weigh between 245 to 345 tonnes.

The piles were lifted off the deck of the vessel using a 60 metre crane and driven into the seabed with a 225 tonne anvil and hydraulic ram.

In the summer, the Seaworker will have been joined by the MPI Adventure, a new self-propelled jack-up vessel. Over the next nine months both vessels will continue to install the remaining 176 foundations in preparation for the installation of the two offshore substations in the summer and the start of installation of the 175 wind turbines towards the end of the year.

The monopiles and transition pieces were brought to the site from Germany and Denmark on ABJV’s transportation barges.

The foundations will now begin to arrive and be installed in a pre-determined pattern, each one having been designed and built specifically for its installation location.

London Array is being built around 20km off the coasts of Kent and Essex. The wind farm will be installed on a 245km2 site and will be built in two phases. Phase One will cover 90km2 and include 175 turbines with a combined capacity of 630MW. The consortium plans to complete the first phase by the end of 2012. If approved, the second phase will add enough capacity to bring the total to 1,000MW.

The project consortium partners have the following shareholdings: DONG Energy owns 50%, E.ON has 30% and Masdar has a 20% stake.



Source: londonarray, March 08, 2011