Work has begun on the world?s biggest offshore wind farm

As people begin arriving in Brussels on Sunday for the European Wind Energy Association  2011 Annual Event, it’s a safe bet that many of them will be talking about what is expected to become the world’s largest offshore wind farm.

The three wind power developers of the London Array announced that the first of 177 foundations of wind turbines has now been installed at the London Array Offshore Wind Farm in the Thames Estuary.

The press release — put out by DONG Energy, E.ON and Masdar — noted each foundation will consist of a tubular steel monopile, driven up 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 up to 65 metres long and weigh as much as 650 tonnes, while the transition pieces are as high as 28 metres and weigh up to 345 tonnes, the press release said, adding the piles will be lifted off the deck of the vessel using a crane and driven into the seabed with a hydraulic ram.

The London Array is being built approximately 20km off the coasts of Kent and Essex. It is scheduled to be built in two phases. The first phase, which is expected to be completed by the end of 2012, will include 175 turbines with a combined capacity of 630 MW and two offshore substations.

If the second phase is approved, there will be enough capacity to bring the total to 1,000 MW. The London Array could power up to 750,000 homes and reduce CO2 emissions by 1.9 million tonnes a year.

“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,” Anders Eldrup, CEO of DONG Energy, was quoted as saying.

According to the press release, 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.”

Currently, the Thanet Offshore Wind Farm is the world’s largest. Operational in September, the Thanet facility located off the coast of Kent has a capacity of 300 MW, enough to supply more than 200,000 homes with emissions-free electricity.

By Chris Rose, blog.ewea.org/