How Black Paint Can Cut back Fowl Deaths From Wind Generators

Wind generators kill quite a lot of birds, significantly eagles and different raptors. The precise quantity is unknown, as a result of lots of the world’s wind farms don’t monitor hen deaths. One mitigation concept to cut back these numbers—and assuage a political argument towards wind generators—is gaining traction: Paint one turbine blade black. Ecologist Roel Could spoke with IEEE Spectrum about his 11-year examine to cut back raptor deaths, and his shock on the lukewarm reactions from wind-turbine engineers.

How unhealthy are wind generators for birds?

Roel Could: It relies upon so much on the place you place the generators, and whether or not there’s breeding or foraging areas close by, and the species of birds. In the event you put wind generators smack in the midst of a weak inhabitants, the impact will be fairly massive. That’s what occurred in Norway on the island of Smøla, which is a scorching spot for white-tailed eagles. That’s the place we did our examine.

Why are eagles prone to wind generators?

Could: Raptor species like eagles are superb at flying, however they don’t look straight forward; they appear down on the floor for prey. They like to make use of updrafts to soar, however updrafts are frequent close to ridges the place wind circumstances are good for generators. In order that’s a nasty mixture.

Does the wind-turbine kind make a distinction?

Could: Bigger generators kill extra birds as a result of their blades take up extra space. However the place wind generators are smaller, there’s usually extra of them, so these wind farms could find yourself killing extra birds than farms with fewer, bigger generators, at the least onshore. Offshore wind farms are more durable to review: You’ll be able to’t depend the precise variety of birds that die as a result of you’ll be able to’t discover them; they fall into the ocean and so they’re gone. Some researchers try to document collisions with hen radar, cameras, and different methods.

You discovered that portray one blade black resulted in a 70 % decline in hen deaths. Ought to all wind farms be doing this?

Could: Our examine is one thing that needs to be repeated elsewhere as a result of there are seemingly site-specific and species-specific results. A bunch in the Netherlands painted blades and hasn’t seen a transparent impact. So we want extra research. There’s one examine stepping into South Africa the place they painted a blade crimson, and a few others which might bebeginning in Wyoming, Italy, and Spain. The United Kingdom is planninga pilot venture for offshore generators. However these research are arduous to do as a result of the operator has to get exemptions from rules to color the blades and rent licensed painters who can rappel up and down. And it takes quite a lot of time. We collected knowledge on eagles in Smøla for seven years earlier than the blades had been painted. After we painted, we spent 4 extra years finding out the results.

How did engineers reply to your examine?

Could: Lots of people from turbine producers requested if I had thought-about the technical implications of this. I hadn’t, as a result of I’m an ecologist, not an engineer. Apparently black blades will warmth up greater than white blades, which can trigger structural results. And the black paint is made with carbon, which may have an effect on the turbine’s efficiency when hit by lightning. Engineers don’t like that. So we have to overcome these disciplinary silos and work collectively to develop useful mitigation measures.

This text seems within the June 2025 print challenge as “Roel Could.”