The foundations for the English Lincs Offshore Wind Farm have now been handed over to the client, who has begun to install the first wind turbines.
The foundations for green energy to 200,000 UK households are now in place. MT Højgaard has handed over the foundations for 75 offshore wind turbines for the Lincs Offshore Wind Farm off the east coast of England, and the first wind turbines have already been installed.
“We installed the last foundation in June, and in September our divers came up out of the water for the last time after completing all the final work,” says Kim Andersen, Director of Offshore at MT Højgaard.
The final work included fitting so-called J-tubes, which lead the cables from the wind turbines to the sub-stations. The J-tubes are installed using a crane from a jack-up vessel, but a diver is required to guide the equipment into place below the water surface.
“As with installing the foundations for the offshore wind turbines, the final work also includes being able to handle heavy gear with millimetre precision, and getting the logistics at sea to run perfectly,” says Kim R. Andersen.
Being market leader in offshore wind turbine foundations, MT Højgaard possesses all the competences required to ensure that design, planning, logistics and execution all take off together. The company has demonstrated this particularly over the summer when, concurrently with completing its work on the Lincs Offshore Wind Farm, it has also installed the last of the 111 foundations for the Anholt Offshore Wind Farm, the biggest offshore wind farm in Denmark.
The foundations for both the Anholt and Lincs projects have been designed and executed with a conical grouted connection, which complies with the new regulations for calculating grout connections.
Lincs Offshore Wind Farm lies approx. eight kilometres from the coastal town of Skegness on the English east coast. First power from the 270 MW offshore wind farm was generated in August 2012 and the wind farm will be fully commissioned during 2013. Each foundation consists of a monopile weighing between 320 and 480 tonnes which is driven into the seabed. A transition piece, which weighs approx. 290 tonnes, is then lowered onto the monopile; the wind turbine is then fitted onto the transition piece.
Number of turbines: 75
Wind turbine: Siemens 3.6 MW
Water depth: 8.5-16.3 metres
External diameter of monopile: 4.74-5.20 metres
Weight of monopile: 320-480 tonnes
External diameter of transition piece: 5 metres
Weight of transition piece: 290 tonnes
Top grade elevation of foundation: +6.5 metres
Client: Joint venture between Centrica Energy (50%), DONG Energy (25%) and Siemens Pro-ject Ventures (25%).