That's a good question. At first there was a real problem with the yaw bearing. Anytime the wind changed direction there was a loud metal against metal grating noise that reverberated though the house. I was able to completely eliminate that problem with a teflon pad on top of the mast and some grease.
The jury is still out on alternator vibration. The first set of blades I built did not work very well and the machine almost never reached cut-in speed. I'm in the process of making a new set of blades now that I expect to have mounted in about two months. I'm also planning to cut down one tree directly behind the turbine. Then I hope to get more vibration data (and I hope that is little or none).
