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Large, modern wind turbines are very quiet. At distances of more than 180 meters, the swishing sound of rotor blades is usually masked completely by wind noise in the leaves of trees or shrubs. There are two potential sources of noise from a wind turbine: mechanical noise from the gearbox or generator, and aerodynamic noise from the rotor blades.

Mechanical noise has virtually disappeared from modern wind turbines because of better engineering with more concern about avoiding vibrations. Modern wind turbine gearboxes use “soft” gearwheels-i.e., toothed wheels with hardened surfaces and relatively elastic interiors.

Aerodynamic noise-i.e., the “swish” sound of the rotor blades passing the tower of a wind turbine-primarily occurs at the tip and the back edge of the rotor blade. The higher the rotational speed, the louder the sound. Aerodynamic noise has been cut dramatically over the past ten years due to better design of rotor blades (particularly blade tips and back edges) and lower RPM machines. Pure tones can be very annoying to a listener, while white noise is barely noticed at all. Rotor blade manufacturers take extreme care to ensure a smooth surface, which is important to avoid pure tones.

Wind energy leaves no harmful emissions or residue in the environment. Wind energy has a proven safety record.

On open, flat terrain, a utility-scale wind farm will require about 100 acres per MW of installed capacity. However, less than 5 percent, or 3 acres, of this area is actually occupied by turbines, access roads, and other equipment; 95 percent remains free for other compatible uses like farming and ranching. A wind farm located on a ridgeline in hilly terrain will require much less space, as little as two acres per MW.
Since wind turbines extract energy from the wind, there is less energy and more turbulance in the wind shade of a turbine than in front of it. On a wind farm, turbines are generally spaced between three and nine rotor diameters apart in order not to shade one another. If there is one particular prevailing wind direction, turbines may be spaced very closely in an orientation that is at a right angle to the wind direction to avoid shading. For instance, if the prevailing wind blows from the west, turbines may be placed north-south.

Wind turbines are obviously very visible, since they must be located in the windy, open terrain to be economical. Many factors can improve the visual impact of wind farms including a good design, the careful choice of paint color, and precise visualization studies before siting. As other well-designed structures, wind turbines can furnish a landscape with new architectural values.

After the useful life of a wind farm has elapsed, foundations can be reused or removed completely. Because there is so much steel in a wind turbine tower, the scrap value of a turbine more than covers the costs of restoring a site to its initial state.

Terrain is very important. The energy content of the wind varies with the cube (i.e., the third power) of the wind speed. Twice as much wind yields eight times as much energy. Therefore, manufacturers and wind farm developers seek to site wind turbines in the windiest areas possible. The roughness of the terrain, its contours, and even the presence of buildings, trees, plants, and bushes affect the local wind speed and may create turbulence, which may decrease energy production and increase the wear and tear of the turbines.