Wind turbines produces little steady electrical current, and even if you go with peak energy production from these things and couple with solar there is a cost to the environment. A large wind farm that produces any sort of useful amount of electricity for private or industrial consumption takes the wind out of the environment as a system in the same way that damming a river takes the water out. You have a "dead zone" where there is little wind and above you have a much higher flow of wind, which can only lead to the wind above pushing down over some distance from the wind farm to fill the void and dumping down inland (because if you put the things too far out you would need really long cables). This would increase the temperature inland and has the potential to change weather patterns close to the surface of the earth (where is of course most important to us living there). Here's a video in the crazy greenie sinister tone, but might be what future environmentalists have to deal with.
The environmental impacts of large scale wind energy production are pretty much completely untested for and could potentially be very bad. There has been little actual scientific research, and this has been almost entirely due to moneyed "greenie" groups (a single group in the US brings in yearly 100m dollars in income!) opposition to performing basic research in a proper scientific study.