When people talk of the environmental effect of wind turbines and wind power, they often forget to mention the problems wind turbines cause to local wildlife. Birds are an obvious problem to wind turbines; as many turbines are erected at cruising level for birds, many ecological campaigners were convinced bird fatalities would increase due to intereference from turbines.
Wind turbines are usually painted white, so they seemingly blend with surrounding cloud. This, however, is what makes them such hazards to birds; who may not notice the turbines until they are fatally close to the revolving blades.
Statistics show that the effect wind turbines have on birds is negligible. That is, wind energy from turbines is no more costly to bird welfare than other forms of renewable energy production (such as nuclear power) and is actually 20 times less dangerous than traditional fossil fuel production plants.
While birds are safe, it is becoming apparent that bats are not. Nocturnal and blind, winged bats are becoming the silent victims of wind turbines as their usual navigational tools which help them avoid collisions are interupted by the rotating blades.
As well as collisions, bats have to deal with the low pressure caused by wind turbine tips. If they are lucky enough to avoid colliding with the tips themselves, the low pressure generated can cause a condition known as barotrauma. Bats lungs are damaged by exposure to this low pressure, and it can be fatal. Birds have more robust lungs and are not effected by this condition.
So while birds are doing well with wind farms, further research is required on the effects on the bat population. The most obvious solution is placing radar transmitters on top of turbines; bats avoid these, as they trigger their sonar navigational systems.