Why do all wind turbines rotate the same way?
As far as I have seen, the blades of all Danish wind turbines run in the same direction, i.e. clockwise. Is there a technical reason for that?
The short answer is: No, it is not the wind’s fault, and no, there is no technical reason for all blades to rotate the same way.
It looks chaotic if the blades turn different ways when there are several turbines close to each other, so there is a visual reason. But there is nothing technically or physically preventing them from turning the other way.
When the blades turn clockwise (when viewed from the front), it’s actually just because the blades builder felt it was best.
The right-turning blades have a witty mini-anecdote attached to their birth. They are invented as a kind of small rebellion against the Tvind organization. Wind is symbolized in a windmill, which turns to the left – anti-clockwise – just like all other windmills did in the past.
When the first independent Danish blade supplier , Erik Grove-Nielsen, had developed a larger blade in the late 1970s, he decided, with the help of his wife Tove, that it should rotate opposite the Tvind mill.
Erik Grove-Nielsen delivered i.a. to Vestas, and the right-hand turbine became more and more widespread as the industry grew. After a few years – the story is told according to Erik Grove-Nielsen himself – local politicians had to enforce in local plans that wind turbines had to turn clockwise, because it looked completely wrong when turbines turned each way.
Today, the right-turning wind turbine has completely out-competed the old, left-turning wind turbine. But that is why the Tvind turbine may well continue to turn the ‘wrong’ way:
