Multi rotor wind

Engineering
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@dougselsam
The folks at multi rotor are building what they can, analysing what they can, and sharing what they can with the extremely limited resources they have.

Sure you can weld 6 250kW turbines to a frame but you won’t learn a lot if you don’t know all the initial conditions and manufacturing of that original turbine. Yeah you could compare it to another you can somehow buy and weld to a fixed pole.

The growth in turbine sizes suited the needs of developers not turbine manufacturers.
More MW per km2 needed specialist blade manufacturing facilities which got outmoded very quickly.

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Yeah, it’s only on the order of 40% less steel

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Where does the saving in steel come from? Seems there is more structure, not less?

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AWE is believed to have the potential to harness a huge reservoir of high-altitude wind energy. This is potentially more attractive than multi-rotors which are a supposed way to make existing wind turbines better, or getting worse.

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One original example I found impressive was Michael Laine of Space Elevator fame - I saw him generating a lot of excitement over a cool idea. Of course I stilll like the idea of a space elevator, and am still in contact with them. But one might note there is no actual space elevator after all these years.
Michael was more recently surprised to find he had been an inspiration for me. But over time, I have realized there is a big difference between getting people excited over possibilities, versus fully developing a robust and economical product with high performance and longevity, that could serve as an actual solution.

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That cliff looks like the one where the gannet colony is on Bressay (near here)
Huge cliff and multiple wings in the air… Not as coordinated in a massive landing circle pattern as the puffins in the Shaint Isles do

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China installs world’s 1st dual-headed wind turbine to harness hurricane power (msn.com)

Funny how they say it’s installed, but don’t show it installed. Par for the course in wind energy “news” these days. And of course, it’s going to “harness hurricane power”. Mmm-hmmm… One more newbie talking point. I was thinking of putting together a list of 100 of these “press-release breakthroughs” and then, over time, see how many turn out to be true. What do you think?

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You need to go 30 years back in time to search for press releases, then see how many make sense today.

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Installed and commissioned are also very different states of progress to report

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As would be producing power in a category 5 hurricane.
“Furthermore, the OceanX platform is designed to endure Category 5 hurricane conditions, withstanding winds up to 161 mph (260 km/h) and waves as high as 98 ft (30 m). Remarkably, it can continue producing electricity even in these extreme conditions by turning into the wind.”

I think they mean “turning OUT of the wind”. In the language of wind energy, it is called “furling”.
That’s how my 10 kW turbine on a 120-foot tower here protects itself, but in a storm, even sideways, unbelievably, there is so much power in the wind that it can still exceed the capacity of its inverter, which then “lets it go”, after which the blade tips exceed Mach 0.6 (disturbingly loud).

Having been in with the leading manufacturers for decades, including the manufacturer of this one (who offered me a job), I’ve always been told turning sideways to the wind to avoid overspeed is not practical for turbines over about 10 kW. Their new one has a larger diameter and uses electronic stall control instead of turning sideways. (Sorry for using technical wind energy industry language here).

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Three similar “press-release breakthroughs”:
The first is from Japan, a multi-rotor Savonius, in this case, with counter-rotating rotors.
US to test Japan’s unique wind turbines that generate power even at 7 mph (msn.com)

““These compact vertical turbines are successfully used in densely populated areas throughout Japan,” said Craig Nakamoto, HCDA Executive Director.”

Yeah, sure they are…
BTW, in all the years of counter-rotating dual-rotor turbines utilizing a counter-rotating generator to help with the low RPM, I’ve never seen one actually completed or working. Typically, as with the California Energy Commission counter-rotating turbine seeking to take advantage of that talking-point doubling of the RPM, building that counter-rotating generator turns out to be too much of a bother, so they just use two separate generators. How many times do we need to see a Savonius “announced” as a “new breakthrough”. No wait, how about “game-changer”?

OK Here’s a very similar Savonius press-release breakthrough that just made “the news”:

Ukrainian schoolboy’s innovative wind turbine opens new opportunities for urban wind energy (msn.com)

Since we’ve discussed the best designs for Savonius here before, I won’t burden you with all the details of why this idea doesn’t meet those characteristics. But hey, it’s a kid, right? Give the kid a favorable article! After all, it’s “global warming” where facts don’t matter, just what fits on a bumper-sticker!

OK now here’s the coup-de gras: This one has gotten a LOT of press coverage lately.
And THIS multi-rotor turbine is “ACTUALLY BECOMING A REALITY!!!” How do we know? It says so in the article, silly! You can’t doubt anything about a supposed “new” wind energy device (er, um, rendering) that appears in an actual ARTICLE, can you?

A designer’s wild ‘wind turbine wall’ idea is actually becoming reality (msn.com)

I guess it’s supposed to be in production (checks watch) right about now! So go get one. BTW, I guess the wannabe “inventor” has been agonizing over the details of “his design” - exactly how to design and build his Savonius - still working on that, but when he gets to that point, he “will” build them into “a wall” and you “will” be able to power your home with his wall. Got it?

Since turbines like this are supposedly already available for purchase, not sure why this “inventor” is still hemming and hawing over the exact design for them, but when he figures it out, look out!

Here’s another article on his “breakthrough”:
Designer turns clean energy into an aesthetic choice with ‘wind turbine wall’: ‘If it’s not beautiful, we have failed’ (msn.com)

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Here’s another one about the multi-rotor turbine that will certainly, without any doubt, withstand category-5 hurricanes, due to its special construction (except they don’t have hurricanes in China, only tyhoons)

Oh, and by the way, the “clever” subtitle is “Winds of Change” - how many idiotic articles use this phrase, all thinking it is original? The La Brea Tar Pits of wind energy journalism?

China Installs Giant Wind Turbine Built to Harness Power of Hurricanes (msn.com)

Another article about the hurricane turbine in Asia. Except I think the same storms we call hurricanes are called typhoons there, so maybe it will never see a category 5 hurricane, only typhoons.

Anyway, I think maybe when they talk about the turbine surviving category 5 hurricane winds by "turning into the wind’ they might mean “pitching the blades to feather position”. (Again, sorry to use actual wind energy terminology in this venue!) This is what all utility-scale turbines do, so there is nothing new about it. I’d love to see a video of it surviving 90-foot waves and 163 MPH+ winds - that would be entertaining, if you could actually see ANYTHING in such conditions. But, well, it’s “an article”(!) so everything in it MUST be true, just like every article about AWE is definitely 100% true, as we’ve seen for - at least 16 years now, and counting… tick tick tick tick tick…

And there is a great advantage to a turbine continuing to produce power in winds over 163 mph, because even though that could only happen a teeny fraction of 1% of the time, it’s important, because, well, you know - insistent idiots and know-it-all know-nothings need meaningless bumper-sticker talking points to entertain and calm their confused minds.