Increasing wind turbine rotor blade visibility reduces avian fatalities | Hacker News Reader

Increasing wind turbine rotor blade visibility reduces avian fatalities

onlinelibrary.wiley.com

206 pointsseigando69 comments

I'm all for reducing avian fatalities from wind turbines. But it's also important to understand that this is not going to make a significant dent in how many birds are killed by human causes. Glass buildings kill 2500 times as many birds as wind turbines. House cats kill 10,000 times as many.

https://www.statista.com/chart/amp/15195/wind-turbines-are-n...

The type of solar plant that uses mirrors to reflect sunlight to a focal point also vaporizes some # of birds per year, likely negligible though compared to the causes you listed.

Source? That sounds awesome. I mean, terrible. >_>

https://www.sciencealert.com/this-solar-plant-accidentally-i...

There's another big one in southern Spain which I saw from the air on a flight a while ago: https://en.wikipedia.org/wiki/PS10_solar_power_plant

Here's the famous SoCal one which is impressive to drive by: https://en.wikipedia.org/wiki/Ivanpah_Solar_Power_Facility

Instead of using photovoltaic panels (PV), they're called CSP - concentrating solar power. Basically concentrate a bunch of heat on a tower and drive a steam turbine to generate power.

https://en.wikipedia.org/wiki/Concentrated_solar_power

WSJ reporting on some controversy in the past: https://www.wsj.com/articles/ivanpah-solar-plant-may-be-forc...

Pretty much this. If you have a cat, keep it indoors! A bell on the collar isn't enough.

Yup, cats will learn very quickly how to move while keeping the bell quiet

Famous writer Jonathan Franzen has become very involved with birds, and wrote about cats being really bad for birds and therefore the environment [0].

[0]: https://www.thedailybeast.com/the-war-on-cats-jonathan-franz...

It will make a significant difference for specific species of birds, such as assorted eagles and other raptors, that generally live away from cities with their tall glass buildings, and that would quickly kill any house cat foolish enough to try to take them.

Wind turbines tend to be built in the same kind of places those birds hunt.

True. Residents of Juneau know not to let cats and small dogs play outside because eagles will take them.

So yeah, I'm all for this technology but it bugs me that we hear so many people who are obviously trying to defend fossil fuels and denigrate renewables couch their rhetoric in terms of "the poor birds!" Yet we never hear them advocate bird-saving technology for tall buildings (which does exist) or keeping house cats indoors.

Yeah, I saw a pro-logging meme that said sarcastically "Save a tree, wipe your &$$ with an owl." (context: https://www.seattletimes.com/seattle-news/owl-ruling-halts-l...)

You know it's disingenuous.

As do those who have coyote populations. I wonder if the bird life has been studied, where cats are less likely to be allowed outside.

A training room in Texas would routinely be interrupted by a loud bang against the window.

Without missing a beat the instructor would calm the students by explaining that it was just the local eagle.

It was a daily occurrence by the same eagle.

His nest was visible outside the window.

This seems like a noisy low-probability event.

> While the number of recorded carcasses increased at the control turbines (7 vs. 18), they decreased at the treated turbines (11 vs. 6 [expected: 28]) (Table 1).

I didn't read the article very closely, but it also reads like they're doing lots of hypothesis tests on different groupings to find significant (p < 0.05) results:

> However, the annual fatality rates fluctuated considerably between years (Figure 3 lower panel), stressing the necessity of a long‐term study. Seasonally, fatality rates (across years) were strongly reduced at the painted turbines after treatment during spring and autumn, but increased during summer (Figure 4). When grouping data by season instead of years, painting reduced seasonal fatality rates by 70.9% (95% CI: 61.7%–77.7%; z = −2.003, p = .042, n = 64).

I'm not convinced.

I agree with you.

For some reason, every now and again studies like this -- ones that are interesting but under-researched -- are posted on HN, and I don't get why. People then treat these studies as if they are conclusive evidence of something. Luckily nothing ever comes of it, but still

maybe the results of their test will spur some doubting Thomases to pick up the mantle and have a go themselves. They'll either find supporting results or disagreeing results. Either way, sounds like good science.

If they are taking the results of the single study to say "This is the final answer", then that would be bad. If they are just saying "These are the results we achieved", then that sounds like what a study is suppose to do.

To be quite frank, repeated hypothesis tests on ad-hoc groupings is _terrible_ science.

I regard this as another pilot program, to be scaled up. Gotta publish to get more funding.

> The most common species found were willow ptarmigan (Lagopus lagopus), white-tailed eagle (Haliaeetus albicilla), common snipe (Gallinago gallinago), hooded crow (Corvus cornix), and meadow pipit (Anthus pratensis) (Table S1). Eagles are large conspicuous birds and will therefore often catch the attention of passers-by. Ptarmigan are often found near the turbine base as they are suspected to collide with the actual tower

This disproves my assumption that many of the collisions were with nighttime migratory birds (maybe that is buildings?). I hope this simple fix applies to all locales and is not specific to Norway.

Last night I watched an episode about Eagles on PBS NOVA. They said predatory birds like eagles are constantly looking down and they also have a ridge above their eyes to block the sun. They basically don’t look up, maybe the white looks like clouds so they don’t think they can run into it.

It’s a pretty cool episode. They use eagle watchers to turn off turbines when an eagle gets too close but the human can’t see in the direct sun. They built a robot with a 360 camera and 2 cameras that rotate to find eagles. It worked much better than a human.

IdentiFlight system: https://www.identiflight.com/

Wind turbines are painted white to reduce their visibility (particularly effective on overcast days). Humans don't want to see wind turbines, birds do. I wonder wether the turbines can be painted a color which blends in with the natural scenery for humans but is really visible for birds.

> For this study, we maximized the contrast by applying black paint. What remains to be tested is whether other color regimes will be equally effective, for example, red stripes as used for aviation warning purposes, green paint to reduce visibility (to humans) in the landscape or optical or holographic coatings. In the experiments by Hodos (2003), yellow and red, but especially green blades had slight—but nonsignificant—visibility advantages over black; which was therefore suggested be simplest and most effective to implement.

It looks like they are hoping for the change to test other options, now that this first study shows promise.

Can't birds see into the ultraviolet part of the spectrum? I wonder if you could get the blades to emit enough UV light for them to avoid it.

If anything the black works because it absorbs UV (and visible) light.

You would have to check whether emitting UV light attracts insects. If they do, chances are the insects would attract insect-eating birds, and death rate could go up, even if the birds can see the blades better.

Don’t birds see UV? Won’t that show as black for those who see it, and transparent for those who don’t? If so, putting sunscreen on the blades would work.

Who doesn't want to see turbines? They're so neat. And even if they're white you can clearly see them unless you have trouble seeing. A few times a year, my son and I drive past a wind farm and make references to this xkcd https://xkcd.com/1378/

I admit I might be weird though, I routinely wish that the pipes and wires were on the outside of the drywall, and I took the doors off my pantry so I can see everything.

I'm sure you don't mind when you're just driving on the freeway, but wind turbines are also being installed in places where there's a lot of natural beauty, for example https://www.fortum.com/about-us/our-company/our-energy-produ... (flattering picture, you can probably find much worse examples)

The tricky part is that it depends on the human.

For instance, I don't find natural forests or mountains more beautiful than well maintained cropland or pastures or gardens; they are just different kinds of beautiful. (Since I grew up on a farm, I call this "the farmer aesthetic".) I also don't think I would find well-maintained, visible -- even colorful! -- wind turbines to detract from a scene of natural beauty; it would just be a different scene than it was before, not inherently worse for that difference.

But I acknowledge this is not a universally-held aesthetic.

A lot of buildings used in rural areas definitely aren't aesthetic pleasing, massive industrial buildings where the primary concern is build cost. They provide jobs to the region so people treat it as a necessary evil. People need jobs but power just comes out of the wall... Then can generate it elsewhere (not in my back yard), that's what I believe the primary issue is. Wind turbines also work better on hill and where the surrounding area isn't obstructed, so by definition they're a little tricky to hide.

What I've always found odd is how windmills are loved and wind turbines are hated. Maybe tell people they're windmills?

But in all seriousness, power generation is something that isn't discussed as much as it needs to be. Electric vehicles are coming fast (fuel prices are surprisingly low right now, but it never stays that way..) and when you consider the number of vehicles about, that will take quite a bit of power (or Angry Pixies as a certain Youtuber would say). Energy does have a cost to the environment (there isn't an easyway around that), but it also has a cost to the economy, there's no simple answer which is why I think it isn't discussed enough. I'm pro nuclear, on a renewable energy tariff and I'd argue natural gas makes a lot of sense in the UK - That's just my answer.

> A lot of buildings used in rural areas definitely aren't aesthetic pleasing, massive industrial buildings where the primary concern is build cost.

It's always nicer when things look, well, nice, but the core of the aesthetic is purpose: a thing with a purpose, that fulfills its purpose, is beautiful. An endless field of wheat or corn, a massive concrete grain silo, and an array of windmills all have a purpose which they are exquisitely performing, and so they are beautiful.

(One of my favorite instantiations of the farm aesthetic is the multi-generational farm, with some buildings that are post and beam or stone, some that are cinder block, some that are sheet metal, etc. Each building was simply built according to what was the cheapest vernacular construction technique of the time, but the combination conveys a sense of continuation beyond the simple permanence of an old structure. This farm was fulfilling its purpose generations ago, and will continue to do so for generations still. It is not static; it is living and changing.)

Large building projects have a habit of becoming part of the landscape. Consider big bridges or mountain pass roads and railways: in the perception of those who experienced both the before/after they surely all ruined that view, but to those coming after them, the same structures tend to be a highlight.

In the Swiss Alps, people take far more pictures of the Landwasser Viaduct than of the untouched parts next to it. This is an extreme example (because it's so exceptionally pretty), but the same is true to an only slightly lesser extent about most other things that have been built into those nice landscapes. (the dark cavities of the new Gotthard that dominate the view from the old Tremola are a rare exception)

Yes, this. Lighthouses are another good example.

>This is an extreme example (because it's so exceptionally pretty)

For a more pedestrian example, search for images of "letchworth state park upper falls". Note that photographers rarely try to crop out the railroad trestle even though it's much less pretty than everything else in the picture. It's an accepted part of the landscape and the aesthetic.

Even more pedestrian is that without obvious man made structures most scenes are going to show the direct impact of humans. It’s just we’re used to it.

I'm not seeing the problem with that picture...

News article from the Norwegian Institute for Nature Research: https://www.nina.no/english/News/News-article/ArticleId/5037...

This research's analytical technique is so cool, I'm almost giddy.

Another hypothesis is that white paint attracts insects, which then attracts their predators.

I'm hoping experimenters continue with all sorts of crazy paints and patterns, optimizing for visibility to misc birds.

I'm certain that we can do many incremental improvements to reduce bird mortality.

figuring there isn't much of a weight difference, I do wonder if the thermal difference with one blade being black will have any impact on performance and longevity of the structure as a whole.

Is there really thermal concerns for wind turbine blades ? These things are literally aircooled by the wind, aren't they ?

Yes, but they are also exposed to significant stresses. The tips Can move at hundreds of kilometers per hour, and of course the blades are constantly subject to rotational forces as well.

They are only cooled by the wind when there is wind. Sometimes there is a lot of sun and no wind. One side of the blades will heat up more than the other, and potentially undergo rapid cooling when a rainstorm hits.

Maybe the black blade gets so hot that it disintegrates birds via steam explosion, leaving no carcass for researchers to find and catalogue, leading them to the erroneous conclusion that black-painted windmills kill fewer birds.

EDIT: /s

It's going to affect longevity somehow due to uneven wear. But whether that means 2 hours less service or 2 years I have no idea. In Norway, where it is not generally as hot as some other locations, probably 2 hours.

Maybe the whole blade doesn't need to be black? It sounds like they're going to experiment with different colors and patterns but I do wonder whether a black outline painted on the blades or even one black stripe down the center of the blade would be sufficient to put the birds on notice.

Paint the fronts of every blade black, and leave the backs white.

The wear should be even (because the weight is balanced), and you'd even get a (granted, likely unmeasurably small) boost in output due to the sun!

https://en.wikipedia.org/wiki/Crookes_radiometer

... the problem being that birds can approach the turbine from either side.

This is a bit of a silly thread, but I'm curious if that's the case.

Assuming that the issue is that the blades are hard for birds to see, not "impossible", then having them black on the windward side may solve the problem.

For a given wind speed `x` and bird flight speed `y`, the relative speed when approaching the blades from the windward side would be `x + y`. The relative speed when approaching from the leeward side would be `x - y`, giving the bird additional time to react.

... on the other hand, at `x + y` the bird's body would pass through the blade plane is less time than at `x - y`, potentially reducing the likelihood of a strike.

Now I'm curious if there are data showing where birds have been found dead are wind turbines. Intuitively, I would expect there to be more dead birds on one side than the other.

I would think most birds don’t fly straight into a blade, but get hit from the side (modern turbines are large; tips of blades will easily hit 100mph)

That would make relative speed in both cases about equal.

The real missed opportunity here is the one-two combination of reducing avian fatalities and advertising with LEDs:

https://ae01.alicdn.com/kf/HTB15.LQMVXXXXXNXpXXq6xXFXXXZ/GTF...

But seriously, is there a way to illuminate the blades in a low-cost way that's obvious to birds and invisible to locals? Intensity, visible wavelength, frequency?

I'm more curious if there are other colors or patterns that would be more effective at warding away birds. For instance, would bright red or neon orange be more visible? Or could you co-opt existing danger-patterns like the red-yellow-black of a coral snake or the pattern of a monarch butterfly to trigger the "I am poison, stay away!!!" response in birds explicitly, rather than just being visible as "oh hey there is a giant thing there"? If we created a novel patterning for wind turbine blades (or highways, for that matter), could animals develop an aversion for it, and how long would that take?

The paint scheme they tested:

https://onlinelibrary.wiley.com/cms/asset/41ca0d89-d383-425e...

I find it fascinating how much discussion and effort goes into birds hitting wind turbines compared to the number of birds and mammals killed by mountain top removal coal mining or killed in slurry ponds.

Do you have a resource in mind for learning about those too?

In UK coal mining has all but ceased but wind turbines are on the increase, do it seems natural to talk more of the latter in any context.

I'm always amazed how inefficient cross industry pollination is. This was a major issue in aerospace for years (see Hudson River) and there are a number of solutions, one of the best being a high pulsing light on the wings. How has that not gotten pulled over to the wings of a wind turbine?

Did they try posting a scarecrow on top of the turbine?

Or at least a conspicuous vane on the leeward/downwind side that makes the whole thing a little more conspicuous to birds.

I bet a drone that looks like an eagle would help

Lacks ((RGB LED) persistence of) vision.

Why waste the opportunity to have giant advertisement displays like in Bladerunner?

Would it be possible to emit high frequency sound that's undetectable to humans to warn birds away?

No negative reactions from local human inhabitants are known to us.

Maybe not the locals, but I think they're underestimating internet conspiracy theorists ability to turn this into something.

But I certainly hope large scale policy/infrastructure decisions are made to appease internet conspiracy theorists.

I hope you intended a "not" to be somewhere in there lol

Sarcasm over the internet fails again

It's clearly a big hypnosis wheel to make you accept Bill Gates' covid-19 vaccine chips. Wake up sheeple.

There were 3 white blades, now there are 2.

2x3=6

the black blade can be in 3 positions! 6 6 6 !!!

This is clearly illuminati signaling to reptilian overlords that its time for invasion.

Buy my book for more details. xD

How about a drone with computer vision to identify birds and chase them away?

This company does fixed cameras which identify birds and then temporarily shuts down the relevant turbines: https://www.identiflight.com/.

I think evolution should largely take care of the problem here. Evolve or die. It's the natural order.

Evolution typically is a slow process. Not that smarter species don't have learned behaviors that is passed down outside evolution that can compensate. If a species is unable to adapt, loosing it can be an important part of an ecosystem potentially triggering a further cascade impact. Obviously we (humans) compete for resources on a grand scale and generally don't care about the ants we squish along the way, but it is worth considering the impact, understanding the repercussion. As much as we would love to believe otherwise, we can't survive without the biomes around us.

Reply on news.ycombinator.com