Adverse impacts of wind energy
Besides a minuscule effect on fossil fuel emissions and the high expense of extracting any meaningful energy from such a diffuse, intermittent, and variable source (particularly as other sources must still be maintained and built to balance the highly fluctuating wind infeed as well as to supply 100% backup for when the wind doesn't blow), wind turbines have many other adverse impacts.
Wind turbines meant to supply the grid are hundreds of feet in height, each with blades sweeping a vertical air space of 1.5 to 2 acres (0.5–1 hectare) or more. At night they require warning lights for airplanes. Because they need to be well away from where people live and work, and because they need a lot of open space around them to adequately catch the wind and not interfere with each other’s wind, they are necessarily erected in formerly undeveloped places: typically farmland and mountain ridges. They inevitably dominate the landscape and destroy the special character, the peace and quiet, especially at night, of those places. (See also “Noise” and “Tourism” below.)
Wide strong roads, clearance for transmission lines, electrical substations, huge buried foundations of concrete and steel rebar, staging around each turbine for maintenance as well as initial construction, hundreds of gallons of coolant and lubricating oil in each machine, the noise and direct physical toll of the turning blades ... wind energy facilities are sprawling industrial installations with obvious environmental impacts: destruction and fragmentation of habitat, alteration of groundwater and runoff, disturbance and deaths of animals (see “Wildlife” below)...
Wind turbine blades sweeping a vertical air space of 1.5 to 2 acres (0.5–1 hectare) necessarily create noise as they thus remove energy from the wind to turn the generators. The gears and the generator also make noise as they turn. The characteristic pulsing noise of wind turbines is likely due to the different air pressures at the top and bottom of the blades’ rotation area. The passing of each blade by the tower likely also contributes.
Furthermore, because the blades are mounted on towers hundreds of feet in height, the noise may be projected a great distance, particularly at night (owing to atmospheric inversion causing sound waves to bounce back down to earth) and particularly infrasound and low-frequency noise. The latter not only travel farther without attenuation, but also penetrate walls and windows and can even resonate with them.
Because large wind turbines are necessarily erected in previously undeveloped places, the addition of this noise – usually from many more than just one machine – is especially intrusive, particularly at night.
- See also: Wind Watch documents concerning noise
- See also: Wind Watch documents concerning health
Although there is a shortage of desirable housing in most rural places and people often have to makes compromises in their choices, nobody, given the choice, would choose to live near a giant wind turbine, let alone several of them. That unavoidably affects property values.
See: “Reasons NOT to Sign a Wind Contract”, by the Coalition for Rural Property Rights (Iowa)
- See also: Wind Watch documents concerning tourism
For flying animals – birds, bats, and insects – the giant turning blades pose a direct threat. The blades sweep a vertical airspace of 1.5–2 acres (0.5–1 hectare) at tip speeds of 150–200 mph (240–320 kph). Animals on the ground are affected by the destruction and fragmentation of habitat as well as the noise and vibration.
- See also: Wind Watch documents concerning wildlife
Bats have been observed to be curious about the large structures and are thereby subject to collision. But most of the deaths are due to barotrauma caused by the low air pressure behind the blades.
- See also: Wind Watch documents tagged for bats
Migrating birds generally fly far above the heights of wind turbines — except in conditions of fog or low-lying clouds. On landing and taking off, they have been observed to avoid wind turbines – but only in clear mild conditions, not in fog or rain or at night. Raptors (predatory birds: eagles, falcons, hawks, owls, vultures, etc.) are at risk of collision with wind turbine blades while they hunt, when their attention is focused on their prey, which is usually more abundant in the vast clearances around wind turbines. Thus, wind turbines, as they do with bats, attract the activity of raptors.
- See also: Wind Watch documents tagged for birds