Construction venture focuses on turbine foundations

Costain has teamed up with Hochtief and Arup in a new alliance that aims to help design and build the foundations for offshore wind turbines.

While offshore wind farms can take advantage of more predictable and consistent weather conditions than their onshore counterparts, constructing them in an offshore environment is more technically challenging.

Many such wind farms, for example, will require large concrete structures, known as gravity base foundations, to be constructed. These foundations – flask-shaped concrete structures 30-40m in diameter, 60-70m tall and weighing around 6,000 tonnes – sit on the seabed and act as a platform to which the wind turbines can be attached.

The consortium is currently assessing suitable sites for port facilities where they could produce the foundations in high volumes. According to Costain director Colin Duff, they would be constructed by a slip-forming process operating round the clock.

’To meet the aspirations of the UK government in terms of its targets for renewable energy production, any facility producing such foundations will have to be capable of producing a unit every two to three days,’ said Duff.