In an interview with Windpower Monthly, Felix Ferlemann said he was "confident" the company would develop a new, larger turbine to take advantage of the cost-cutting benefits of larger offshore machines.
Siemens' competitors such as Mitshubishi and Daewoo already have 7MW models in development, and Ferlemann said it made sense for manufacturers to exploit the cost-saving potentials of larger turbines.
He said: "If you install a wind park of a certain megawatt, you can halve the installation costs because you need half the foundations, half the pilings, and that reduces the cost dramatically. So the cost reduction potential of having higher power ratings in offshore [turbines] is very good."
Ferlemann said it would take the company "some years" before it developed anything larger than its 6MW turbine, and that it would wait until it had experience of this machine and the new direct drive technology it uses before bringing anything larger on to the market.
But he added: "I cannot tell you what will be the next size, but I really feel that 6MW is not the limit. I’m pretty confident there will be a further increase in the power rating for offshore."
He said direct drive technology made it possible to envisage larger models: "Our new direct drive technology has 30% less weight than a comparable machine; we have 50% less parts, which is related to maintenance and reliability. So that is the right way to go – reducing complexity. And then with this new technology you are able to grow."
See Windpower Monthly's EWEA 2012 Liveblog day 2