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Increasing wind turbine rotor blade visibility reduces avian fatalities
- eganist 6y agofiguring 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.
- navaati 6y agoIs there really thermal concerns for wind turbine blades ? These things are literally aircooled by the wind, aren't they ?
- pcl 6y agoYes, 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.
- jzwinck 6y agoThey 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.
- EForEndeavour 6y agoMaybe 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
- sgc 6y agoIt'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.
- elliekelly 6y agoMaybe 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.
- Ancapistani 6y agoPaint 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 https://en.wikipedia.org/wiki/Crookes_radiometer
- saalweachter 6y ago... the problem being that birds can approach the turbine from either side.
- Ancapistani 6y agoThis 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.
- Someone 6y agoI 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.
- ourmandave 6y agoNo 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.
- KiranRao0 6y agoBut I certainly hope large scale policy/infrastructure decisions are made to appease internet conspiracy theorists.
- Cthulhu_ 6y agoIt's clearly a big hypnosis wheel to make you accept Bill Gates' covid-19 vaccine chips. Wake up sheeple.
- me_me_me 6y agoThere 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
- sradman 6y ago> 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.
- wil421 6y agoLast 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/ https://www.identiflight.com/
- barbegal 6y agoWind 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.
- OldHand2018 6y ago> 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.
- Analemma_ 6y agoCan'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.
- barbegal 6y agoIf anything the black works because it absorbs UV (and visible) light.
- Someone 6y agoYou 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.
- ornornor 6y agoDon’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.
- elwell 6y agoDid they try posting a scarecrow on top of the turbine?
- frafra 6y agoNews article from the Norwegian Institute for Nature Research: https://www.nina.no/english/News/News-article/ArticleId/5037/S-229-effektive-er-tiltakene-for-fuglevennlig-vindkraft https://www.nina.no/english/News/News-article/ArticleId/5037...
- 3JPLW 6y agoThis 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.
- TheSoftwareGuy 6y agoI 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
- dylan604 6y agomaybe 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.
- 3JPLW 6y agoTo be quite frank, repeated hypothesis tests on ad-hoc groupings is _terrible_ science.
- specialist 6y agoI regard this as another pilot program, to be scaled up. Gotta publish to get more funding.
- vz8 6y agoThe real missed opportunity here is the one-two combination of reducing avian fatalities and advertising with LEDs: https://ae01.alicdn.com/kf/HTB15.LQMVXXXXXNXpXXq6xXFXXXZ/GTFS-Hot-AAA-battery-Powered-LED-Programmable-Message-Fan.jpg 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?
- saalweachter 6y agoI'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?
- mrfusion 6y agoHow about a drone with computer vision to identify birds and chase them away?
- cornellwright 6y agoThis company does fixed cameras which identify birds and then temporarily shuts down the relevant turbines: https://www.identiflight.com/ https://www.identiflight.com/.
- deevolution 6y agoI think evolution should largely take care of the problem here. Evolve or die. It's the natural order.
- mey 6y agoEvolution 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.
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- specialist 6y agoThis 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.
- dreamcompiler 6y agoI'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-not-killing-fields-for-birds/ https://www.statista.com/chart/amp/15195/wind-turbines-are-n...
- umvi 6y agoThe 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.
- AdmiralAsshat 6y agoSource? That sounds awesome. I mean, terrible. >_>
- umvi 6y agohttps://www.sciencealert.com/this-solar-plant-accidentally-incinerates-up-to-6-000-birds-a-year https://www.sciencealert.com/this-solar-plant-accidentally-i...
- zzapplezz 6y agoThere'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 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 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 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-forced-to-shut-down-1458170858 https://www.wsj.com/articles/ivanpah-solar-plant-may-be-forc...
- Petrova 6y agoWould it be possible to emit high frequency sound that's undetectable to humans to warn birds away?
- fred_is_fred 6y agoI 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.
- pbhjpbhj 6y agoDo 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.
- frank2 6y agoThe paint scheme they tested: https://onlinelibrary.wiley.com/cms/asset/41ca0d89-d383-425e-97e7-bf55b854322f/ece36592-fig-0001-m.png https://onlinelibrary.wiley.com/cms/asset/41ca0d89-d383-425e...
- LargoLasskhyfv 6y agoLacks ((RGB LED) persistence of) vision. Why waste the opportunity to have giant advertisement displays like in Bladerunner?
- soapboxrocket 6y agoI'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?