If wind has kinetic energy - E, the amount that can be harvested is < E, and that was kinda obvious from the start. Turbines stop the wind, hence one country can stop wind blowing towards another country if they put many fields on the "track". And apparently it hasn't been taken into account when making those optimistic statements regarding zero emission energy. Also this IS ecology altering, and might have an effect in global weather, but not sure how much (wind mainly blows at high altitudes).