what are its environmental effects ?
Eelatively minor compared to that of fossil fuels. According assessments of the life-cycle greenhouse-gas emissions of energy sources, wind turbines have a median value of 12 and 11 (geq/kWh) for offshore and onshore turbines, respectively.
Wind power
The environmental impact of wind power is considered to be relatively minor compared to that of fossil fuels. According to the IPCC, in assessments of the life-cycle greenhouse-gas emissions of energy sources, wind turbines have a median value of 12 and 11 (geq/kWh) for offshore and onshore turbines, respectively. 
how much power does a wind mill produce 34.5kV what is wind power ? Wind power or wind energy is the use of wind to provide mechanical power, it is a sustainable, renewable energy source that has a much smaller impact on the environment compared to burning fossil fuels. what are public opinions related to it ? Surveys across Europe and in many other countries show strong public support for wind power.
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Wind power [SEP] Environmental effects
The environmental impact of wind power is considered to be relatively minor compared to that of fossil fuels. According to the IPCC, in assessments of the life-cycle greenhouse-gas emissions of energy sources, wind turbines have a median value of 12 and 11 (geq/kWh) for offshore and onshore turbines, respectively. Compared with other low carbon power sources, wind turbines have some of the lowest global warming potential per unit of electrical energy generated. Onshore wind farms can have a significant visual impact and impact on the landscape. Their network of turbines, access roads, transmission lines, and substations can result in "energy sprawl".