Some talk about Dust Devils and Thermals

You have trees?
I thought you said it was windy there


To be honest, I have never heard of such in Norway, so this problem of dust devils may not be universal.

Hi Roddy: I live in a more open area. We have about a half-mile of open space before the wind gets to this place. Yes I have some trees planted out along the road, but they are not upwind of this place. I’ve been careful to leave all upwind space open, not only for wind energy, but both my front yard and backyard are able to serve as airplane runways. This is a mountain pass called “The Cajon Pass”, famous around here for high winds and bad weather including snow in the winter. The fallen tree is in a residential neighborhood a couple miles downwind from here. Strange that I happened to be right there when it blew down. I was looking at a fence I own being almost blown over, then I heard a big CRACK and saw the tree being slammed to the ground. It was very quick. Oak Hills (here) has about two hundred 10-kW wind turbines powering homes. They zero out the electric bills. Now, that is, not “next year”… :wink:

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Hi Tallak: Well, you can get rotating air anywhere. Without dust, you would never see it. You might just feel a gust of wind, maybe a few gusts, possibly with changing directions if the center went through your exact location, or notice your wind turbine suddenly sped up and changed directions more quickly than usual. Do you have waterspouts? Maybe there is some magical place that always has smooth air, but in general, a wind energy system needs to be able to handle such turbulence. You could maybe build one of these machines in the picture and see how long it lasts at your location.

Do You Know How Dust Devils Form?

You seem to need specific conditions for dust devils to form, one being low wind at the surface. So not when you’d launch your kite. I think their frequency also probably correlates to the frequency of tornadoes in your area. If tornadoes are not a thing in your life, dust devils with enough energy to do damage – and that at the altitude of your kite – probably are not either.

I’m a little more interested in the more general and more frequent phenomenon of:

@dougselsam mentions dust-devils as a specific problem for

a stacked-savonius with multiple levels of rope-drives would fare in such a rotating airmass

Can other AWE architectures being more compliant with dust-devils?

10 waterspouts were spotted at once recently…
Looks a bit like a network of kite turbines.

Actually we have about eleven or twelve miles of open space upwind of here, starting at the 5000-foot Crestline Hang Glider Launch
Which we see the back side of,
then the wind blows over the very windy Silverwood Lake
Then over about nine miles of rolling hills and chaparral,
then over a few ranch properties with houses and trees
til it gets to the half-mile or so of flat ground leading up to this spot.
So there is another house about a half-mile upwind - our nearest neighbor to the South - name is Bob. Just a few scattered Joshua trees between here and Bob’s house. They don’t block much wind. We’ve had the windiest season in many years. Sometimes I wish it would just stop. Hold on to your hat! :slight_smile:

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