Costain has teamed up with Hochtief and Arup in a joint venture to design and build offshore wind farms.
“Offshore windfarms offer the prospect of more predictable and consistent weather conditions than their onshore counterparts, together with fewer problems in gaining planning permission,” said Costain director Colin Duff. “However, constructing them in an offshore environment is more technically challenging.
“These installations will require large concrete structures, known as gravity base foundations, sitting on the seabed and into which the wind turbines can be attached. This is where Costain comes in.”
Bidding concluded this year between various developers, energy providers, and Crown Estates (which owns the rights to the seabed around the UK) for Round 3 of the licences that will allow companies access to the seabed to install the wind turbines.
"If everybody develops the sites they say they're going to, the offshore market could be worth £200bn by 2020. The foundation element of that is £50bn," estimated Duff.
A gravity base foundation would be a flask-shaped concrete structure 30-40 metres in diameter, 60-70 metres tall and weighing around 6,000 tonnes.
“Winning contracts will come down to having an affordable, deliverable solution," said Duff. "The most efficient way of achieving this is by setting up a manufacturing facility to mass produce the gravity base foundations."
To meet the aspirations of the government in terms of their targets for renewable energy production - of which offshore wind is a major part - the facility will have to be capable of producing a unit every two to three days
The consortium is currently assessing suitable sites for port facilities to produce the foundations, said Duff. They would be constructed by a slipforming process operating round the clock.