A study at a wind farm on the Norwegian archipelago of Smøla performed for nine years. The research has shown that if the color of one of the blades is black, then 70% deaths of birds by wind turbines can be reduced. Only replacing white color with black helps to reduce the bird deaths every year due to collision with the blades of the wind turbines.
Wind turbines are a cheaper and cleaner source of energy, due to their importance over 60GW capacity of wind turbines added worldwide only in 2019. The demand for wind energy is increasing day by day. If located at the right site, then wind turbines can produce a significant impact. The noise level and pollution are deficient as compared to coal or other sources of energy.
Alongside this, wind turbines cause deaths of birds every year as birds collide with its blades. Estimates from the US Fish and Wildlife Service calculated that wind turbines killed approximately 300,000 birds in 2015. The politicians and other people dislike this source and even call it a bird-killing machine. The U.S President Trump said it to be “Birds Graveyard.”
The laboratory results suggest that the birds may not be able to see the obstacles while flying. The not to see obstacle can be changed if we use black color blades. In this way, a color change can help the bird to spot the obstacle.
Study at Smøla Wind Farm
At the Smøla wind farm, regular checks of four particular wind turbines—each 70m tall with three 40m-long blades—found six white-tailed eagle carcasses between 2006 and 2013. The four turbines killed 18 birds that flew into the blades over those six years, along with five willow ptarmigans that are known to collide with the turbine towers rather than the blades.
In 2013, each of the four turbines in the test group had a single blade painted black. In the three years that followed, only six birds were found dead due to striking their turbine blades. By comparison, 18 bird deaths were recorded by the four control wind turbines—a 71.9-percent reduction in the annual fatality rate.
Variation in deaths in different seasons
During spring and autumn, fewer bird deaths were recorded at the painted turbines. But in summer, bird deaths actually increased at the painted turbines, and the authors note that the small number of turbines in the study and its relatively short duration both merit longer-term replication studies, both at Smøla and elsewhere.