Scientists are studying impact of painting wind turbine blade black to reduce bird collisions

(SEPTEMBER 26, 2024) Researchers from Oregon State University are working with a team to reduce the number of birds hitting wind turbines by painting one of the blades black.

Wind energy is important as the world faces climate change, growing energy needs, and moves from fossil fuels to clean energy. However, it also poses a risk to birds and bats, as many die each year from collisions with the turbine blades.

The Oregon State researchers are working with partners from the government, industry, and nonprofit groups, with funding from the Oregon Legislature. They are building on earlier research from Norway that showed bird collisions dropped by 72% when one turbine blade was painted black.

“This was a big result, but the study involved only a small number of turbines,” said Christian Hagen, a senior researcher at Oregon State University. “Before changing policies, scientists in North America want to test this on more turbines and look at different bird species to see if it works without causing other problems.”

Twenty-eight turbine blades at a wind farm in Wyoming have now been painted black to see if it helps reduce deaths among eagles, other birds, and bats. The idea is that painting one blade black will make the turbines more visible to birds, helping them avoid hitting the blades.

Eagles and other birds that are active during the day may see the painted blades better, while bats, which rely more on sound and have different vision, might not notice the painted blades as well.

The project started after Oregon lawmakers gave $400,000 to Oregon State in 2021 to study how painting blades black affects bird deaths. Hagen teamed up with PacifiCorp, a company interested in the research and with a perfect location for the study.

Hagen is working with doctoral student Natia Javakhishvili, who is building a model using data from the research site to see if painting the blades leads to more birds avoiding the turbines. She is especially focused on golden eagles, a species that is often affected by wind turbines. Javakhishvili is using data on golden eagle movements to make the model more accurate.

“This study is special because it looks at bird movements in three dimensions, including altitude. This will help us understand how birds like eagles fly around turbines, roads, and power lines, and will help us protect them better,” Javakhishvili said.

At the Wyoming site, researchers and trained dogs are also searching for bird and bat remains. Javakhishvili will use some of this information to predict how wind energy affects ferruginous hawks, a bird species found in western North America.

Hagen says that as the research results come in over the next few years, they will help guide wind energy companies and government agencies in reducing bird collisions with turbines. Many of the birds impacted by turbines are protected by federal laws.

Researchers are also watching similar studies happening in Spain, Sweden, and South Africa.