Wind power is booming right now, with over 60 GW of new generation capacity added worldwide in 2019. As long as you put the turbines in the right place, wind power is surely cheaper than combustion. of fossil fuels. And most people would rather live next to a wind farm than any other type of power plant, even solar.
However, not everyone is a fan of wind turbines due to their impact on local populations of flying wildlife like birds and bats. Politicians who want to fight renewables say we should keep mining coal and oil due to bird death toll, and US President Donald Trump has called wind turbines a ‘bird cemetery'[s]. “Estimates from the US Fish and Wildlife Service calculated that approximately 300,000 birds were killed by wind turbines in 2015 (which is probably two orders of magnitude less than the death toll from collisions with wind turbines. power lines every year), and bird deaths from turbines are trending downwards as the industry shifts to larger, slower moving turbine blades.
Bird deaths caused by wind power can then be overestimated, but they still happen. Previous lab studies have suggested that birds may not be very good at seeing obstructions as they fly, and adding visual cues like different colored fan blades can increase the birds’ chances of spotting. a fast rotating fan.
At the Smøla wind farm, regular checks of four particular wind turbines – each 70 m high with three 40 m long blades – found six white-tailed eagle carcasses between 2006 and 2013. In total, the four wind turbines killed 18 birds that flew into the blades. during those six years, as well as five willow ptarmigan which are known to collide with turbine towers rather than blades. (Four other turbines selected as a control group were responsible for seven bird deaths, excluding willow ptarmigan, during the same period.)
Thus, in 2013, each of the four turbines in the test group had a single blade painted black. Over the next three years, only six birds were found dead due to impact on their turbine blades. In comparison, 18 bird deaths were recorded by the four control wind turbines, a 71.9 percent reduction in the annual mortality rate.
Digging deeper into the data, there was some variation in bird deaths depending on the season. In the spring and fall, fewer bird deaths were recorded in the painted turbines. But in the summer, bird deaths actually increased at the painted turbines, and the authors note that the small number of wind turbines in the study and its relatively short duration both deserve longer-term replication studies. , in Smøla and elsewhere.
Ecology and evolution, 2020. DOI: 10.1002 / ece3.6592 (About DOIs).