In the National Renewable Energy Action Plans submitted to the European Commission this year, many EU member states cite energy generated by offshore wind farms as a major contributor to renewable targets. However, only around 2GW of offshore wind capacity is operational in European waters, and while huge progress has been made, many technological challenges need to be met before the EU can achieve its offshore goals.
Figures from the European Wind Energy Association (EWEA) and other sources suggest another 3.5GW of offshore capacity is under construction. A further 18GW more has been given the go-ahead, bringing Europe’s total pipeline by 2020 and beyond to 140GW. The UK leads the EU, boasting around 1.3GW of offshore capacity, with Denmark next on 0.65GW. According to EWEA figures, the UK is set to remain the EU’s number one supplier, with 49GW under development or planned, while Germany is forecast to take the number two slot with just over 35GW.
Simon Luby, advisory services manager at renewables consultancy SgurrEnergy, agrees that the EU offshore market is poised for growth. "There are lots of projects at an advanced stage that can be expected to start construction within the next six to 24 months," he says. Most of these - including the Lincs, Sheringham Shoal, London Array, Gwynt y Mor and Ormonde wind farms, are in the UK, though there are significant projects coming online elsewhere, including phase two of Thornton Bank in Belgium.
For Nicolas Fichaux, EWEA’s head of policy analysis, the greatest advances of the past 12 months are the "positive market signals" given by the UK and Germany, especially, in outlining plans to build manufacturing plants and test facilities. Meanwhile, he says industry and governments are thinking more about collaboration between projects. "In the North Sea, we now know there will be clusters of offshore farms, and discussions have turned to issues relating to merged infrastructures, such as dedicated harbours, or the need for facilities at sea where maintenance people can be based and spare parts can be stored," he explains.
The idea of joint working is also growing on the technology side, according to Luby, who has observed standardisation across projects. He explains that while every project has its own technical and commercial shape, most now use 3MW or 3.6MW turbines. He says most are being built on monopile foundations in water no deeper than around 20m, using "tried and tested" methods, contractors and specialist vessels such as Resolution or Seajack. Almost all are being built by utilities on a multi-contract basis.
Luby is doubtful about the prospects of 10MW offshore turbines, pointing instead to the potential offered by 6MW to 7MW machines, which he says could be in a physical prototype phase within the next 12 to 24 months. "Suppliers with smaller but proven machines, for example Vestas, Siemens and Nordex, are now actively developing prototypes of 4MW and above," adds Luby. "The more fanciful 10MW ideas cannot make any commercial sense until they are classed as bankable from a project finance perspective and until enough vessels exist that are large enough to install them in volume."