Did they clear out the spruce / pine trees forests?
The wind resource is significantly worse in wooded areas. The ideal setting is dead flat - hence the appeal of ocean deployment. Any sort of object that causes a change of wind direction sacrifices a lot of power, as does an irregular surface such as a forest.
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I think it varied, but that was the idea. There was a forest in Fife that I often walked the dogs in, and they would clear an area for timber, install a turbine, and replant around it.
If you want to see environmental destruction in Scotland, just check out the grouse moors.
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For reasons that donāt extend much beyond āitās cheapā, this is the fastest growing region of the US
https://x.com/jonathanweisman/status/2089480047266554058?s=20
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The tldr is that this design is really only good at utilizing mediocre wind resources, and is unable to capture the vast majority of energy from a good wind resource.
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I liked the thought that there are still clever people pecking away at making things better for the environmentā¦ As in, from one good idea, another will spring from itā¦ 
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Would that also be true if this kind of turbine was much bigger?
Itās interesting that it produces much less noise than a conventional turbine, and is less dangerous for birds.
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The video makes it sound like it is a radical innovation, but the idea of using an Archimedean screw to harness wind has been around for a while. It is essentially a more efficient permutation of the Savonius design. It has all of the benefits claimed in the video, low cut-in speed, etc.
As you can see from that graph, the Savonius is great at harvesting the wind resource at very low tip speeds (which are a function of wind speed), and as stated in the video it is not particularly susceptible to changes in wind direction. However, it falls far below the theoretical extraction limit (the Betz limit) of 16/27 of the wind energy and saturates at speeds below the cut-in speed of most other designs.
The property of being able to generate almost all the time sounds great, but once you understand where the energy actually is it becomes evident why the three-blade monopole design is dominant. Power density is given by the function:
P = Ā½ * Ļ * A * v3
Where ro is the air density (not a constant, but not far off), A is area (circle of the blade sweep for the conventional design) and the cube of velocity.
So, where the Savonius type can capture energy at 3 m/s before the other design even cuts in, it will peak around 5 m/s. Assuming a 1 meter area and air density of 1 kg/m3 (1.225 kg/m3 at 15 C at sea level, but math kept easy for illustrative purposes) at 5 m/s there will be 62.5W available. The Savonius will capture a peak of 15%, and down to about 8% at 5 m/s, so not quite 5.5W of output.
By contrast, the 3-blade is cutting in usually around 4 m/s and capturing perhaps 40%, so 24W at 5 m/s. But the real story is when the wind reaches 11 m/s or thereabouts. With 665W of energy available, the 3-blade will be approaching 48%, or about 320W. The Savonius will still be spinning out 5.5W. At 320W, it doesnāt take long to overhaul the 5.5W, even if the 5.5 is near constant.
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Thanks for posting this. I had always wondered about that.
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Faaaaack!
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The Colorado basin is heading toward full collapse. Lake Mead is in Shortage II (of 3) at about 1030 feet, just 30 feet from the water level cutting off supply to southern Nevada. At 950 feet, all power generation stops - although it is already far below peak output. The 895 foot level is ādead poolā, water does not get past the Hoover Dam and delivery to most of the rest of the basin stops. The last intake, basically emergency water for Nevada, is in the air at 860 feet.
For context, it has only ever been in Shortage II once before, 3 years ago.
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Unrelated perhaps but weāve had one of the warmest winters I can recall bar a few odd days. It never really gets that cold but this was mild to say the least. On another note, Iāve often bemoaned the fishing and using it as some kind of marker.
The shad Iāve mentioned came late this year and further north such as Durban as beyond had very little come through. The sardine run this year was patchy at best as well. Strangely enough when they did come through here on the south Coast of KZN, they were of sizes unseen for over a decade of my memory. Iāve caught 50cm plus shad regularly since July and others have been even bigger. Very noticeable in their almost complete absence were the smaller ones. As a percentage of personal experience from what Iāve caught and what Iāve seen at the spots Iād estimate that less than 5% were under breeding size. Everyone was rejoicing but its left me feeling very uneasy because the smaller ones are just as voracious if not more so thus if they were here, theyād have been caught. Iām not a marine biologist by any stretch of the imagination but I highly suspect weāre at the threshold of a collapse in the local numbers of the species.
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Itās only anecdotal, but I was last at the Hoover Dam about three years ago, doing a little hiking and exploring with Mrs ROTW in a combo Vegas/walking sort of mini break.
Anyway, my overriding impression was a profound concern and sadness at the receding water level. You could see it so clearly on all the rock faces around Lake Mead. You could also see how far they had to move marina/boat landings as where the shore used to be was now quite far from the lake.
Weāve seen so many bad climate things across he world in recent years, and I fear 2027 will be the worst yet, as the affects of El NiƱo spill out across the globe. 