Imagine they’ve solved the problem of breaking blades and (the software problem of) getting the thing to fly. What are now still first principles problems with the system (flying at a lower altitude). What are first principles reasons why it could work?
This is just another idea for an awes, like I see posted here often. It is more achievable than some, like the Beaujean thing. So I don’t see why the discussion has to be more negative than in all those other threads. Increase the number of angles from which you look at a problem, and the deeper your understanding will be.
Opinions are a dime a dozen and are just noise without the analysis to back them up. What’s your analysis, @Tom? @tallakt? (I can’t give an analysis because I know nothing.)
I might have looked closer at this, but just now it doesnt seem worthwhile to me. Perhaps if they release something more than a 3D rendering…
Let me just say this: Like the Laddermill (Laddermill, third post), the wings are generating crosswind energy, but at the same time moving the wings for power generation perpendicular to the wind direction (wing moving upwards and wind horizontal). This does not scale well I think with higher rotational speeds. You get a lot of force at low speeds, but little power when combined with fast rotation.
The reason that generating energy with motion perpendicular to the wind direction is a consecuence of apparent wind. With such a movement, apparent wind will work very hard against the wing motion. It would be very similar to a Kitemill/Makani Yoyo rig producing directly upwards. Anyone familiar with kites will know that once the tether is released somewhat (and kite moves upwards), the tether force will immediately be almost slack. It’s a matter of geometry, a bit hard to explain.
Another way to approach this is to understand that when harvesting wind energy, you are harvesting the difference in speed wind relative to ground. The tether force acting in the direction component directly against the wind is the basis for your power generation. If the tether is pointing mostly upwards (to reach high altitudes), you are probably not going to harvest much energy because the tether needs to be very strong for a small horizontal component.
Add to this that if you divide the circular motion into four quadrants, forward, aft, up down, only the forward quadrant (a bit simplified) is generating energy, up and down are pure transport while down is a pure loss (but necessary for the function of the device). So only 1/4 of the time, the wing is active.
It might be better if the device was headed mostly downwind instead of upwards into jetstreams.
The reason, why we’re more negative about Brainwhere and Michael Perlberger is, that he’s cocky. Presenting himself like a savior. No humility. He’s actually trying to trick investors into giving him money and get public attention. When he will inevitably fail, people will be disheartened with the whole of awes. He has a lot of credibility, having been in business for a while and having a related MA from Delft. So he should know better. “It is science fiction, but it works.” He states that with the utmost confidence without having tested enough. “Humankind will benefit from it” That’s also why I got into awes, but he says it like he is Prometheus himself.
In contrast to that, the Beaujean thing is a concept by a dead person brought up by a fellow forum member in the category “lounge” with the preface that it’s crazy, but we should discuss it for fun.
Now how can I, with much less credibility, make such a harsh judgement? (Thx, @Windy_Skies, but I’m not an expert either) Because there are simple, understandable reasons, why this will not work. I will not do a detailled analysis since noone’s paying me to do one but this concept can be dismissed without one.
First things first: Can this thing fly as a kite? Yes. Standing still it’s just a mupltiplane. It has pitch control on every surface, so it should be steerable as well.
Can this fly on itself? Probably. Control is very difficult, but it theoretically it should be possible. Even without airfoils or even blades, one can make a magnus effect plane. Is it steerable? Probably. If not one can always add an empennage to the non-rotating part.
Can power be extracted? When he shows the test article in the video, he says how he can get the system to roatate when it stands still or turns very slowly. Then all is good. Positive aoa in front, negative in back and all of them get some wind. Then it is easy to have a bit more lift up than down to keep the system in the air.
But as soon as one starts cranking up the angular velocity, the relative wind on an airfoil changes drastically, other effects set in, the fast moving blades in the back are in the wake of the fast moving blades in front. When the front blade uses its potential as a perfectly aligned crosswind kite, it can faster than the airspeed. But then everything needs to move faster than the airspeed. the top blade when moving backwards would go against the relative wind with the airflow from back to front. I don’t really know what the back blade will do but it certainly won’t be in the position as shown due to relative wind. If the radius is gigantic, so that the front blade does have no effect, then the back blade could have a second optimal point of crosswind flight. At the bottom the blade can provide lift for the system. It has very high relative wind. Namely the wind speed outside plus the speed of the roation which can be higher than the wind speed. Very high drag, extracting energy from the system.
Mechanically this thing is challenging. Pitch control on every whole wing, not just airfoils, rotating very fast. That’s extreme mechanical loads and the whole thing is supposed to be net energy positive.
A generator in the rim. Possible, but unneccessarily complicated. So much friction. There’s a reason why hubless wheels haven’t taken off. Usually in a generator all parts are at work. But not in this one. A large part of the rotor is not in the stator at any time. This means a lot of dead rotor weight.
The concept can be dismissed much more easily when looking at alternatives instead of stating why brainwhere is stupid. Just imagine a not moving makani plite optimised not for crosswind flight, but standing in the air. The system is soooo much less complicated. It’s just a kite with rotors. Very stable and reliable. The rotors move optimally crosswind all the time. A simple well tested hub generator. Much larger swept area per mass, even when not going crosswind! Now imagine it going crosswind. The system which is already much better than brainwhere suddenly becomes a multitude more efficient.
Two sideways airborne versions of the vertical-axis icebreaker propeller: http://voith.com/corp-en/drives-transmissions/voith-schneider-propeller-vsp.html
My prediction: “Vaporwhere” - you’ll never see one fly. Too complicated.
And cross-axis turbines are a known bad design direction in wind energy. Twice the weight per unit power, high nonsteady unnecessary bending forces on the blades, too many unworkable aspects, temporarily glossed over by the irresistible lure of sexy renderings…
Really good find!
The ship propeller addresses some issue that are not present in airborne wind turbines.
Here’s a wiki article ( should have looked for that sooner):
All cyclogyros have a system to counteract torque. The brainwhere system will probably need one, too. The weight of the stator can’t suffice. But I guess engineering comes after selling for our glorious savior.
Looks like they’re headed toward the well-worn path of “mission creep”, where they decide their device will never compete in providing electricity at a competitive cost, anywhere in the world, so they will use an airborne platform to provide a wifi connection.
Some things never change…
It’s almost palpably painful to watch these “companies” make the same, predictable “excuses” in the form of some stated “advantage”. Wifi connectivity. Taking the load off tower-mounted cell phone communication stations… Disaster relief. (Remember Altaeros?)
“Augmenting” real turbines in real windfarms (Why wouldn’t they use more of the same turbines that already work? Why would people combine bad turbines with good ones? Wouldn’t they just pick the best one? So Silly!) (DaBiri)?
Here’s what’s REALLY going on:
One more “Professor Crackpot” comes up with one more unworkable idea for capturing wind energy, but, realizing their idea is as full of holes as their locally-produced Swiss Cheese, they nonetheless decide that “moving the goalpost” can extend the time in which they can maintain enough dubious credibility to keep raising more and more money, so they “switch horses in midstream”, flip-flopping on the reason their effort even exists, suddenly deciding their airborne whatever-it-is that is otherwise unlikely to be useful, can nonetheless offer wifi or cell-tower connectivity. Most people, even investors, haven’t seen this movie ten times already, so they buy into the hype. Since they mention underdeveloped areas, “disaster-relief” etc., it sounds politically-correct (makes your heart bleed for the poor people without cell phones) which emotionally takes down your normal guard against bad, unworkable ideas. Are these people even aware of what they are doing? Or are they mere programmed automatons, unknowingly falling into predictably predestined, well-worn slots of previous inept wannabe “innovators”? This idea is going nowhere, I can pretty-much guarantee, just as I did with Altaeros. It’s an excuse-driven world, at least in certain circles, Sad, very sad. But, an interesting-looking scheme with some nice renderings - isn’t that what really matters? I mean, rings with wings - who wouldn’t want to buy into such nice renderings? I guess even if they noticed it is a “vertical-axis” turbine rotated 90 degrees, they probably think vertical-axis turbines are a good idea too, just that people are too closed-minded to accept them. (back to emotions, and blaming knowledgeable people for the failures of crackpots) Not that hard to get people to throw their money away, especially if it’s someone else’s money. (Like Swiss-Cheese-funded Swiss government money?)
I’m just curious: When you see this, do you “get it” that it isn’t going to work out? That it’s a rendering-based waste of everyone’s time and money?
Or do you fall into the “I can’t really tell” camp?
We discussed brainwhere earlier, I dont remember anyone giving them much hope with their current design. Who knows, maybe a pivot…
I agree we need to change our mindset: When was the last time you were without wifi (or 4G cellular which is now basically as fast and mostly free) OR were in a disaster area desperately needing electricity (and at the same time worried about the emissions of the diesel generator you could have had)
Now think: when was the last time you filled your car with $100 worth of gas, or paid the utility bill of $200.
Now think: where would I go to make money…
Selling to disaster relief is a nice thing if it happened, and could be important for a growth of a company, but its not what you should be aiming for long term
Yup we discussed “where’s my brain” before (How did they pick such an appropriate name I wonder?) and I used the same joke, but this time I added a new joke for this Swiss company: their theory has as many holes as the Swiss Cheese whose taxes undoubtedly helps subsidize their ostensible ring with wings. And the device has holes too - one big hole in each ring. Gotta love those people re-inventing the wheel, eh?
Yes I put $100 of gas into my vehicle regularly, and it only gets about 11 miles per gallon (4.7 km/liter) but my electric bills hover around zero since we have a 10 kW wind turbine on a 120-foot tower here, already installed when I bought the place. It’s almost airborne - always appearing overhead against the sky - even has 3 tethers (guy-wires). Always launched, always ready to spin up at the slightest breeze. It can make power for 30 seconds during a dust-devil then shut down again, all automatically. It can start and stop as many times as needed during indecisive winds. Quite a breakthrough compared to prior AWE systems with such issues as when to start, how to start, when to stop, will they crash?, etc… At some point it will require major servicing, at which point I’ll have to decide whether to replace it with new solar panels for the same price as merely servicing the wind turbine. I remember in 1999 Gasoline was 99 cents/gallon, and I had a minivan I could drive all day long on five bucks. Those were the days… Still waiting for gas to get cheap again.