Offshore wind investments in Europe doubled to a record €13.3 billion (£10bn) last year.
New figures from the European Wind Energy Association (EWEA) revealed a total of 3,019MW of new offshore wind capacity came online in 2015.
That brings the total capacity to more than 11GW.
Around 10 projects – 3,034MW – reached final investment decision last year, it added.
Germany (2,282MW), the UK (556MW) and the Netherlands (140MW) were the three nations to connect new offshore wind turbines to the grid, with 14 projects completed.
Work is ongoing on a further six projects, which are expected to contribute an additional 1.9GW in capacity.
Giles Dickson, CEO of the EWEA said new capacity additions will be lower this year however it is expected to rebound, with Europe seeing more than 20GW in offshore wind capacity by 2020.
He added: “The real question is what happens after 2020. The industry is making real progress in reducing costs but we need governments to give us a clear vision of the volumes they envisage long term and the regulatory framework they’ll apply to drive the necessary investments. Active collaboration between governments is also key: to align their efforts to develop the sector in the North Sea and Baltic.”
Last year Energy Secretary Amber Rudd said the government will no longer issue “blank cheques” for offshore wind projects in the UK.