Whilst there are clearly benefits for the environment in terms of reduced reliance on fossil fuels, the extent of these may not be as much as is claimed.
Wind turbines can only produce electricity when the wind is between a defined speed range. Electricity demand varies considerably at different times of day and year. There is no way to store electricity; demand must be met by immediate supply. Since there is no way to control the wind and determine how much electricity a turbine will produce at a given time, other, traditional energy sources are still needed in order to ensure supply. Thus, the building of wind farms does not mean that other power stations can be decommissioned.
The construction of a wind farm is not in itself "carbon neutral". The manufacture of huge metal turbines, their delivery on specialised lorries, the delivery of huge quantities of concrete for their bases and their actual assembly clearly expend large amounts of energy - most of it fossil fuels.
The extent to which overall CO2 emissions are reduced is not clear cut and, in the past, claims made by Wind Farm companies have been found by the Advertising Standards Authority to have breached their rules on "truthfulness", "substantiation" and "environmental claims