A floating wind turbine that its makers claim could significantly boost the renewable energy sector was officially launched at a trade show in the German capital on Wednesday.

Dutch company Blue H Technologies said its invention, which adapts technology used in offshore oil rigs, was a world first.

It will soon go into operation off the coast of Puglia in southern Italy.

Unlike normal offshore wind turbines it does not need to be anchored to the seabed and can be used in waters deeper than 50 metres (164 feet), depths at which installation costs for fixed turbines become prohibitive.