But the financing of new projects has slowed according to the European Wind Energy Association (EWEA).
Some 277 turbines, totalling 1045 MW, were fully grid connected in Europe during the first six months of 2013, compared to 523.2 MW in the same period a year earlier.
As well as the turbines that were connected, another 254 were erected and 268 foundations were installed.
However, Justin Wilkes, director of policy at EWEA, said the drop-off in financing is a worry.
“The installation rate shows what the European offshore wind industry is now capable of, but to attract investment to the sector, governments need to provide a stable regulatory framework and the EU should set a binding renewable target for 2030,” he said.
“Financing of new projects has slowed down with only one project reaching financial close so far this year. This, together with a lack of orders being placed for offshore wind turbines, substructures and components, reflects the regulatory uncertainty in key offshore markets including Germany and the UK. It highlights the significant challenges faced by the offshore wind sector.”
EWEA says total offshore capacity in Europe is now at 6040 MW in 58 wind farms across ten countries – up from 4336 MW in June 2012.
There are 21 offshore wind farms under construction or in preparation, which together have a total capacity of 5,694 MW.
The 277 wind turbines fully grid connected in the first half of 2013 were in seven wind farms: Thornton Bank in Belgium; Gunfleet Sands 3, Lincs, London Array (pictured) and Teesside – all in the UK; Anholt in Denmark and BARD in Germany.