http://www.newenergyworldnetwork.com/renewable-energy-news/by-technology/wind/dong-energy-e-on-masdar-announces-installation-of-first-177-foundations-at-london-array-wind-farm.html

DONG Energy, E.ON, and Masdar have announced that the first 177 foundations have been installed at the London Array offshore wind farm in the Thames Estuary.

The London Array Wind Farm is being built about 20km off the coasts of Kent and Essex and when completed, will total 1,000MW. The first phase, which will include the installation of 175 turbines and provide 630MW, will be completed by the end of 2012.
Each foundation consists of a monopile weighing 268 tons, which is driven 20 to 50 meters into the seabed. A transition piece is placed on top of the monopile to provide a base for the wind turbine.
The monopiles were installed by joint venture company Per Arsleff Bilfinger Berger Ingeniurbeu GmBH usuing A2SEA’s jack-up barge, Seaworker. A 225 ton anvil and hydraulic ram were used to drive the monopiles into the seabed.
Later this year the MPI Adventure, a self-propelled jack-up vessel, will join the Seaworker to install the remaining 176 foundations for the installation of the 175 wind turbines.
The monopiles and transition pieces were brought to site from Germany and Denmark on ABJV’s transportation barges.