I shot this picture on the very North side of the Island of Hawaii, next to a little airport called Upolu. Cows were munching on the grass and did not seem to be bothered by the wind turbines. This field had around 15.

I'm guessing that the length of each blade is close to 100 feet. Driving to Minnesota last summer, there were several convoys of trucks hauling the blades to a location up there.

And, recently on my drive back from Flagstaff AZ,I passed through Tucumcari,NM. They have a Community College there and provide training for working on Wind Turbines.

http://www.mesalands.edu/wind/?gclid=CJPj5MfJ7Z0CFQEhDQodtHBkQA