Well, the humongous generators inside the windmills do emit a measurable magnetic/electro field, when a few rectifiers / internal gizmo's go bad (which is almost constantly) it can be felt standing under them or walking past, when several go your hair will stand up.
When the cows graze under them & rub on any metal post as cows will do or stick their nose out towards a metal post you can hear the snap from a hundred or more yards away. They will vacate the area in a hurry.
Have a couple of them on each side of a house even 500 - 700 yards away when the rectifiers go your Tv, radio, cell phone, wifi signals go all to poop with tons of interference making it all but useless. Drive a vehicle with the radio on near one malfunctioning you'll hear it no doubt.
Common things folks know that are around them.
Not much of a stretch considering folks been raising a stink for decades about high power transmission lines in populated areas & cancer clusters.