Chronic unreliability, no spare parts and a device that does not work in very many locations ...
If you look at a commercial wind farm anywhere in the world you will notice one thing. Wind farms are always located on flat expanses of treeless plain, on the top of smooth treeless hills or on the edge of the ocean.
This should tell you something about a wind generator. In the absence of steady uninterrupted wind that is free from turbulence a wind generator will not work particularly well and may not work at all.
Perhaps they are not all bad, I have fitted a few that work as advertised and have put a couple in pretty wild locations that have stood the test of time. But I have also fitted wind generators where the manufacturer or importer cannot supply parts, where the device has repeatedly broken and where they plain do not work. Emails and phone calls go unanswered, customers get angry, you may be getting the picture. It is not a happy situation when you sell someone something that does not work or has no spare parts backup!
If you want a wind generator
First get the wind data on your proposed location. You can get this from the Bureau of Metrology online.
Next consider a wind monitoring station. Get one of these from an electronics supply chain like Jaycar or Dick Smith.
Choose a location where a wind generator will work. You need altitude, this is a tower of at least 7 metres in height, 12 - 18 is better, 30 is better again. You need clear unobstructed access to the wind. This means, no trees, no buildings and no hills within at least a 200 metre radius, preferably 400 metres.
Check with your neighbor ... The noise of wind generators annoys a lot of folk. the visual impact pisses off just as many.
Finally if you are an "ask the council" type of person, expect long delays, engineers assessments, red tape and moronic idiots who knows nothing about power generation and everything about bureaucracy.
Forget wind generators unless you are capable of raising and lowering the tower, servicing the unit yourself and understanding all the connections, the regulator and how all facets of the device work. The ability to make parts and balance blades is also useful. If you want a power generation device that will sit outside in the weather untouched for years not require maintenance, get solar panels instead.
Notwithstanding the above, if you have the correct location and are a "hands on" type of person, a wind generator can provide substantial amounts of electricity for a fraction of the cost of solar panels.
Do I sound like I hate wind generators?
In the correct location there is nothing better. Very few folk have the correct location.
Steer clear of cheap units. I have seen cheap wind generators fly to bits in storms with potentially lethal consequences. Try a 300 mm length of fiberglass blade embedded in a front door step. It will make you wonder what would have happened if you had been standing there!
I have seen expensive wind generators stand idle because the manufacturer could not be bothered answering emails or returning phone calls. Idle for 6 months! What a waste of money! Makes me wonder how some folks stay in business ...
I don't hate wind generators, they can be great devices, but I no longer fit them and I no longer sell them. Good luck if you choose one!