In the original Surviving Mars, you could freely rotate Large Wind Turbines after a certain patch. If you have the game, you can test this for yourself in less than a minute; it is still possible.
In Surviving Mars: Relaunched, it is not normally possible to rotate Large Wind Turbines. This mod allows them to be rotated like the original title.

@Greenpier System If a Map "sets a wind direction", then in this case, we can say each map has prevailing winds that will remain consistent in a certain direction. However, we also know that wind does not always blow in a single direction all the time; sometimes it changes due to various factors, and these changes can last a considerable duration.

Wind Turbines existing on Earth today can rotate in response to the direction the wind is blowing, allowing them to maintain consistent power output. Unfortunately, Surviving Mars' Large Wind Turbines are a leaning design, and thus cannot.

@BradenK you never could rotate the big windmills in the original game, at least in base game.

@Techi's Salami Donut I really imagined something. It wasn't in the trailer. It's in the first picture on the steam store page.

@Luxor you must be imagining things, they arent build in a circle in the game's trailer. You can maybe just at the edge see them in the trailer. But they're all facing the same direction. Are you maybe missseeing the rails and terraforming structures as the wind turbines?

Go figure why, but in the game as it stands, they aren't. This makes a small property change to the vanilla buildingdef that enables rotation on them.

@Greenpier System Why where they then rotated in the trailer of the game? There you can see a few of them build in a circle.

I never had an issue rotating fans during placement in the original.

Gojira, they actually weren't.

The original purpose was for the fact they couldn't be rotated to counter the benefit of power that doesn't weaken or die out in a Dust Storm.

They generate MORE during a Dust Storm (meaning they win over Solar immediately, and have an advantage over Sterling or Reactor buildings maintenance-wise) but they have to face the wind to do so.

The direction that the map sets for the wind turbines is supposed to be the direction the wind flows towards.

THANK YOU! I'm sure they were rotatable in the original.