The biggest hurdle has been the developers' typical procurement process which calls for design and build tenders to be prepared in short time periods. This makes it difficult and costly for tenderers to sort out the logistics of constructing and delivering a large number of concrete units.
Steel monopiles, which suit the available windfarm installation vessels, have thus been selected without any significant competition.
Faced with these difficulties, Arup submitted a bid for a Round 2 licence with the support of International Power. This was based on Arup's own transportation and installation barge concept for gravity bases and went one step further than Gifford's proposals by carrying the turbine from shore, thus eliminating specialist offshore lift equipment.
Although the bid was unsuccessful, this approach may well prove to be a good way of introducing new technology for the Round 3 sites especially if these are in water depths that make monopiles impractical.
Gordon Jackson, director, Arup, firstname.lastname@example.org