The world's biggest wind turbine manufacturer has surprised experts by unveiling a new giant seven megawatt offshore turbine.
Danish wind turbine maker Vestas said it expected the new turbine to be in serial production in early 2015.
The manufacturer had been expected to unveil a 6 MW turbine, rather than the huge135m 7 MW unit, with a rotor diameter of 164m - tracing a larger circle than the London Eye.
It is part of a push toward larger and larger units further offshore, where the wind power potential is high and public resistance can be avoided.
Chief executive Ditlev Engel said that the new turbine was designed for North Sea conditions and was the first that Vestas had developed specifically for offshore wind parks.
Wind currently accounts for just 2 per cent of the global energy mix but Engel said that Vestas expects it to provide 10 per cent in 2020, with most of the growth in offshore wind power capacity to 2025 being in Europe.
President of Vestas Offshore, Anders Soe-Jensen, said the company expect the offshore wind market to grow by 8.4 per cent annually from 2015 to 2025.
The UK is the world leader in offshore wind power capacity, having overtaken Denmark, and the new turbine is expected to come in time for the big new British projects planned under Round 3 of the UK's licensing system, Vestas said.
"Just here in Britain, there are plans for 32,000 MW out at sea - that is 10 times the total installed wind capacity of Denmark," Engel said.
The first prototypes are expected to be built in the fourth quarter of 2012, Vestas Wind Systems said..
"Serial production is set to begin in the first quarter of 2015, provided a firm order backlog is in place to justify the substantial investment needed to develop the new production and assembly facilities required for a turbine of this size," the company said.
Engel said the company has not decided where to locate the new plant that would be needed to manufacture the turbine, and he added that the capital expenditure and location would depend on order commitments coming through.
Engel said Vestas had no orders for the new turbine in hand, though customers have been involved in the design process. He declined to say how big he expected sales of the new unit to be.
Engel said that selling wind turbines has become similar to the practice in the airline industry where one sells on the basis of design and then builds the product once one has the backlog of orders to justify the big investment.
He said the plant would preferably be located near a port to facilitate transport.
Vestas's R&D chief Finn Strom Madsen said the new turbine would be equipped with a gearbox, unlike the gearless models being developed by some manufacturers.
It has more than twice the capacity of the company's current biggest 3 MW unit, but is smaller than the world's largest 10 MW wind turbines being built by British, American and Norwegian engineers.