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Wind Farms Environmentally Beneficial?

I have a debate coming up about the Wolfe Island Wind Turbine Project (The second largest wind farm in Canada). The debate is whether or not the Wolfe Island Wind Project, as well as wind turbines in general, are beneficial to the environment or not.

I know there are the simple answers that wind power is renewable and that it doesn’t generate any pollution (except in production it does). What I am looking for (without much success) are the BIG reasons why wind turbines overall benefit the environment (looking at environmental, economical, social reasons, possibly compared to other types of energy). Can anyone help? Links to websites would be awesome as well.