Why wind turbines aren't bird killers
Rotors of wind power plants can be dangerous for animals. Contrary to public opinion, however, only a few birds die from wind turbines.
Wind power plants are currently a hotly debated topic. And certain prejudices persist. One of these is the opinion that many birds die every year as a result of the rotors. But are wind power plants really only good for the environment, but bad for nature? The Swiss Federal Office of Energy has looked into this question. It comes to the conclusion: Very few birds die from contact with rotors.
According to the estimates of the Swiss Federal Office of Energy, 36 million birds are killed annually in Switzerland by human hands or human activities. The biggest bird killers are other animals. For about 30 million birds die from domestic cats. 5 million collide with glass facades, and around one million birds fall victim to traffic.
Around 20 dead birds per plant
In the case of wind energy, bird protection is taken very seriously, the study concludes. This is because numerous assessments must be carried out for each project as part of the environmental impact assessment. Mitigation and compensation measures must also be implemented during operation. Against this background, National Councilor François Pointet (GLP) wanted to know from the Federal Council why such an environmental impact assessment is not also required for glass facades and how many birds actually collide with wind turbines - compared to bird victims on buildings, in traffic and by domestic cats.
The Federal Council notes in its response that the total number of human-caused bird victims can only be estimated. According to estimates by the Swiss Federal Office of Energy, only 20 animals die per year and wind turbine. This figure was collected by the Swiss Ornithological Institute on the occasion of a study at the Peuchapatte wind farm.
Size not crucial
The study also found that neither specimens of endangered species nor birds of prey were affected at the site in the Jura. Also interesting: the three wind turbines built in 2011 do not have radar and are not switched off during bird migration. While there is no environmental impact assessment for glass facades, where about a million birds collide each year, one is mandatory as part of the planning process for a wind turbine in Switzerland.
Another persistent prejudice is that large rotor blades would cause more casualties among the animals. However, researchers came to the conclusion years ago that it is primarily the location, but not the size of the rotor blades, that is decisive.
In addition, work is underway to develop systems that automatically shut down wind turbines when particularly endangered birds approach. However, the effectiveness of such systems is still controversial. In contrast, software is already in use today that automatically stops rotors in certain weather conditions in which, for example, bats prefer to fly.
About the author
Lukas Rüttimann is a journalist, copywriter and storyteller. He has worked for numerous Swiss newspapers and magazines, in various capacities from reporter to editor-in-chief. As a freelancer, he covers a broad spectrum, with sustainable, social, cultural and economic topics particularly close to his heart. Lukas Rüttimann has lived in the USA, among other places, but now lives and works from Zurich.