One of the hardest things we have to do here at Windustry is tell people that they shouldn't try to put up a wind turbine. Most times, people don't want to hear that. They think that we should support any and all wind energy.
The truth is: we're in favor of wind energy when it makes sense. No energy source is a good fit for every situation, and wind energy is no different. In fact, it makes us sad to see wind turbines in inappropriate applications.
The most common bad idea we hear is from well-intentioned city-dwellers wanting to put a small turbine in their yard, usually because they want to do something tangible to combat global warming. I tell them how urban zoning laws can be tricky to navigate, but more importantly, I also tell them that the wind resource in urban areas is usually pretty poor because of all the buildings and trees creating obstructions. They often reply with, "but even if I only produce a little electricity, doesn't every little bit help?"
I understand where these kind city folks are coming from, but the truth is: if your goal is reducing global warming pollution, a poorly sited turbine can harm more than help. What most of these folks are forgetting is that it takes energy to produce the turbine, and most of that energy probably comes from conventional sources, meaning that the production of the turbine actually creates a small amount of global warming pollution.
In a good wind area, this isn't a problem--a turbine's electricity production will more than compensate for the greenhouse gas pollution emissions of it's creation within mere months of installation. However, in a poor wind area--like the city--the turbine may never produce enough electricity to make up the difference.
I think the good news is: in areas with a good wind resource, wind turbines are a huge net benefit to reducing global warming pollution. In areas with a poor wind resource, there are other things you can do to make a difference, like invest in improving your home's efficiency through better appliances, insulation, and CFLs, or even looking into other small scale renewable energy like solar.