I see a turrbine and I want it painted black
No colors anymore, I want them to turn black
I see the birds fly by dressed in their summer feathers
I have to turn my head until my darkness goes
(with apologies to the Rolling Stones)
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The follow up study will study whether painting one blade of the windmill plaid will reduce cat deaths. Excellent suggestion!
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Wow! 70%!
Oh. N is 18. Over 9 years.
And there’s no way to show that painting had anything to do with anything.
There are so many problems with this “study”, I’m surprised you posted this.
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Well that’s a pretty useless sample size.
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I’m not sure the red paint helps humans. We need to run an experiment.
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I’m not sure which, I was legally high af 
Yeah, there’s a section out that way I remember on the way, can’t remember where, was in the middle of a long stretch of scrub brush desert, hills separated by the highway, and just shitloads of windmills on the ridges of both hills. Had to be over 50 of em.
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So we still don’t know if your spirit animal is a willow ptarmigan or a white tailed eagle. Alas.
Seems like that would provide a way better sample size for the study. It wouldn’t be hard at all to make painting one blade a different color SOP for wind turbine manufacturers.
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Unless someone decides to patent it.
It’s almost the opposite. Wind Turbines are typically painted white, pale blue and a handful of other colors specifically to blend into the sky/horizon.
Cause it’s a common point of protest against building wind farms is that they’ll “spoil the view” or that they’re ugly. It’s industry standard as a result of a long history with this.
There’s been a 20 year fight about building an offshore windfarm here. A badly needed one. Early plans to paint the blades to prevent bird strikes were abandoned and swapped for white or pale blue after a serious bout of NIMBY from Cape Cod and Hamptons money. Even though the turbines would seem something like 1mm tall from a boat 1 mile off shore. Gotta preserve those property value driving scenic views.
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I know, right? What if the alternative is a foundry or coal-fired power plant or basically any other option? How scenic are they? I’m constantly surprised that this isn’t a major talking point on these projects.
And then I remember, oh, yeah, demographics of the people who’s views are effected…
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Doesn’t matter those go where the poors live.
I think we transit most of our power down from Canada these days. Used to have a local nuclear plant and one of the villages had it’s own natural gas plant for a while giving them the lowest rates in the region. The option we’ve been left with is “don’t bother” and pay the highest electric rates in the country while having a ridiculously unstable grid.
After that most recent tropical storm rolled through the North East we had no power for 5 days! Then it was back for two! And two more days on the generator! Totally normal!
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Dark-pigment paints tend to be significantly heavier than white paints.
But, as you say: it isn’t hard to control for, just add a smidgeon of balancing weight to the white blades.
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From what I understand they also don’t need to be entirely painted dark. The plan here was a dark stripe on each blade, think a colored center hub. Don’t quite recall, it was the 90’s the last time anything other than hiding them was discussed.
But that would be considerably more flexible in terms of balancing things. If it’s an issue at all.
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There’s one serious, but non-obvious problem with painting wind turbine blades black. Modern turbine blades are made from composite material, where glass, carbon or aramide fibers are hold together by plastic matrix (typically epoxy resin).
All would be fine, but epoxy weakens above certain temperature (it’s called glass transition temperature). Exceeding that temperature would cause turbine blade to fail. That’s the reason that composite structures are typically painted white - for example some composite sailplanes are engineered so that they will heat up just a few degrees C less than the glass transition temperature when stationed near equator.
There are high temperature epoxy resins, but they come with several problems, like higher cost, more difficult technological process and sometimes increased brittleness.
I’m all for applying this solution, but it isn’t as simple as it seems, and painting existing turbine blades may cause unexpected mechanical failures.
Amount of black pigment added to the gelcoat is negligible (it can be as low as few drops per liter of gelcoat), so it’s not much of a problem.
Here’s an example of pigments I used with epoxy resins:
The weight of pigment is typically just 0.01% to 3% of gelcoat weight, and exact percentage is typically closer to 0.01% than 3%.
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Or (as I hinted at in my oh-so-special-way) apply more lighter to the other blades. 
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Interesting, but the data noted in the Ars Technica article don’t support any broad conclusions other than that additional study is necessary.
And those vibrations could cause cancer!
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I’m curious whether painting one blade a different colour would cause it to warp, increasing vibration (and noise) and reducing operational life. I guess the study may mention something.
Also, the article mentions six eagle deaths, and no eagle deaths after painting the blades. Are we sure there wasnt just six eagles?
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I wouldn’t be surprised if it did. The gelcoat is quite thick, and most resins already exhibit significant shirkage. I worked with composites (mostly experimental mechanics, did not do any modeling) and behaviour of composite materials can be quite unexpected, like flat specimens warping under tension.
I think it’s both weird and also neat that this works, that the one black rotor lets birds better get an idea of how fast the thing is spinning. That the one blade is like the second hand on a watch in that regard, whereas if all three blades are the same colour, eyes can lose track and misjudge. The optical imbalance can also leave an illusion of imbalance, making it look more risky to approach.
Just wild speculation on my part, but it feels right.
All in all, an interesting insight into how birds look at the world.
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