I have flown low level survey below 200ft around multiple wind farms in C210's and Pac750 etc. Large turbines, up to 475ft agl. Infront, behind and over the towers..
And have only noticed very slight "chop" but nothing like serious turbulence. The wind varied, but I think 15 kts would be an average..
But I would say, it's not one of the most fun things I've done... trying to pull up to pass over a point that's moving.. that disappears behind the nose..
Pi