[robertakarobin]

Are they? I haven't noticed the sound myself, although I don't live next to windmills and just travel in areas with wind power from time to time... I also grew up next to train tracks and now live next to an interstate near an airport so may have a high tolerance for background noise!

[wood_spirit]

There is one turbine near where I live in Scandinavia that is very noisy. It is a low thumping sound that penetrates houses and is horrid. Those living within a km perhaps more won a court case to remove it but the owner has appealed and appealed and during the years or appeals the thing keeps turning and keeps being noisy so people can’t sleep. My understanding is the simulation and calculations of the noise that were part of the planning process were flawed and did not accurately model the terrain.

Meanwhile, not 5 km away, there are a bunch of turbines with people living around them and no problem.

So the exact slopes etc of the terrain is very important.

[jacquesm]

That sounds very much like either tower thump or a broken bearing, I think the neighbors would have a better case if they pushed the safety angle because a turbine in a bad state of maintenance is dangerous.

Then they'll be forced to fix it and it will be quiet again. You can ask them if it always was that noisy, if it wasn't then that's an extra arrow in their quiver. I'm very much pro renewables but safety is a major concern and operators that do not work safely and/or ignore valid complaints are a net negative for renewables.

[wood_spirit]

In this case it is the terrain. The sound is funnelled somehow. In the planning process the owner has to commission a study that reports if the terrain shape is ok and compute the noise on nearby houses etc. Apparently you can get what you pay for. In the appeal a more independent study pulled the original study apart.