Danish wind turbine maker Vestas issued an unexpected profit warning yesterday caused, it said, by delays to a new generator factory.

The company said the factory in Travemunde, Germany, “is not progressing as planned” and as a result it had chosen to postpone a number of wind projects.

Vestas cut its 2011 revenue forecast to €6.4bn ($8.9bn) from €7bn and reduced its operating profit margin to 4 per cent from 7 per cent.

Ditlev Engel, president of Vestas Winds Systems, said: “I deeply regret that we have been compelled to take this unsatisfactory decision. I want to stress that safety and quality has top priority in Vestas and a decision to speed up the projects in question would have been irresponsible.”

Last night the company’s shares closed 24 per cent down following the announcement.