Oliver: Interesting observation. I think the difference between me and most AWE developers is I start from a standpoint of understanding reality, rather than being indoctrinated with hype and fantasy, so I understand that the idea of improving the basic configuration for wind energy has been tried by thousands of “teams” for decades at minimum, and so far nobody has quite broken through with a different configuration in common use. So what you are seeing is me having a healthy respect for the magnitude of the challenge, rather than pretending it’s gonna be a “slam-dunk”. Just building a standard wind turbine is probably way over most peoples’ heads, let alone revolutionizing the industry with completely different paradigm. When people come along with intermittent, pulsating, cycling, etc. contraptions, I see it as evidence that they are not really understanding how wind energy works, but it is only my opinion. To me, the idea of a wind energy system that not only moves downwind, but is required to stop producing electricity to use a winch to reel it back upwind, is absurd, and I have only to imagine such a thing on the ground to make it seem even more improbable. Many of the configurations originally promoted, like Magenn, have been 100% ridiculous and yet have been treated like royalty and endlessly promoted and publicized in this hype-driven frenzy. How many people “confirmed” the “high probability” that this almost useless configuration was about to power our entire civilization, thousands? I, on the other hand, consistently, from the beginning, flagged Magenn as a joke. So the way I see things, rightly or wrongly, is that my “shoot from the hip” 5-second analysis, is better than any other analysis that I am aware of, simply due to decades of learning, inventing, building and running real wind energy systems, knowing the challenges, the kind of stuff that goes wrong, and the difficulty of getting a system working and keeping it running, even if you don’t invent a single new thing, but just use what is known. So I’m like the leading cheerleader, but also the leading skeptic. These days it seems people are often expected to take some talking-point, emotion-based “position” either confirming or denying things that are unknown. I just say things that are unknown are unknown until they are known. Right now the usefulness of AWE to provide electricity is unknown. When I point out the improbability of a Magenn or any wind energy reality, some people fight it and just want to argue. They quickly degenerate under the pressure, transitioning to an improper, ineffective state where they actually think that the obstacle to overcome is people like me explaining how difficult wind energy is. No, I am just the messenger. The thing to be overcome is the nature of the challenge itself, not people warning how difficult it is. The whole thing can easily turn into a “shoot the messenger” mentality, where in desperation the people who are failing to solve a problem actually blame the person who explains how difficult the problem is. It’s OK we are used to it in wind energy. As I often explain, wind is invisible, so people can imagine it doing whatever they wish it would do, resulting in “wind energy solutions” based on flawed thinking, but the wind does what it wants. In the end, either you have an economical energy solution, or you don’t, and no amount of mere discussion can change that physical reality. I guess that’s the “bad” side of reality. The “good” side is if you DO come up with an answer, nobody can deny it, but it’s harder than that: You need the execution of a good idea, not just the idea itself, or nobody may recognize it is a good idea.
Yep at the end with energy it s all about do you have a performing solution with respect to existing solutions : solar, hydro, genset in term of power, usability, maintenance and cost of course.
Except in the age post-flame wars, noone seems to be arguing that AWE is extremely difficult and perhaps infeasible.
Now I could wish you would shift your focus into «enlightening» us (no sarcasm intended) where you think possibilities are…
AWE prognosis depends of the methodology applied to discover a viable system at utility-scale.
I see three mains approaches among three fields such like wind energy, aerospace, and… airborne wind energy. These approaches may be differently based depending on the field, and can also be cumulative as AWE is also an hypothetical cumulative result of wind energy and aerospace fields.
Incremental approach. The considered basis is a single crosswind yoyo or flygen kite such as described in the seminal Loyd’s publication “Crosswind Kite Power”. This approach is largely majority as shown on the Book of abstracts AWEC 2019 with numerous presentations about sophisticated improvements. The double paradox is elaborating increments on a non market(ed)(able) device being itself a disruptive (not incremental) approach in regard to the known wind energy field.
Where can it lead at the best? The capacity density of wind turbines can reach 8 MW/km², with the possibility of secondary use. But such an AWES takes more than 3 km², preventing any easy secondary use. A reliable and efficient single kite single line 24 MW AWES with reasonable LCOE is highly unlikely. Kite-farms are envisaged, leading to an insoluble dilemma: large spacing so huge land and space use, or low spacing and high risk of mess, the only one safety being the automated control management. This approach is without a way out, although it is useful to test main elements such as automated flight, takeoff and landing. However it is used from years. It is the reason why a second approach is introduced by @Kitewinder (please correct me if you disagree).
Going from simple to more complex. This approach supports the idea that each step corresponds to the materialization of a useful object having a specific market. But in my opinion it does not presume what could be an AWES at large utility-scale. So this approach can generate successful markets by leaving aside systems being too different in size and in nature. Nevertheless this approach can be the more efficient one if AWE shows insuperable limits.
Going from small to large in all dimensions comprising the tethers. This approach does not benefit from possible market until the AWES is large enough. It assumes AWES is complex from the beginning, trying to solve both technical and capacity density requirements which would be far higher as those of wind turbines to counterbalance the lack of reliability and easy secondary use. Simulations would be a useful tool as for space conquest (see the simulations for the tether for exit from space), that due to the numerous parameters that should be taken into account from the beginning. Small prototypes could be tested. An example: testing a 10 m diameter 10 m height rotating reel system could allow if it is workable, knowing no market can be expected.
AWE’s prognosis is fantastic, based on major technological successes (not just millions of years of seasonal bird migration).
For over a century, aviation has saved billions of pound of fuel by utilizing tailwinds selectively, then Kite-sports have blossomed, with millions of practitioners, and now we are enjoying an AWE R&D boom that has already made some folks rich and is providing a wonderful engineering career challenge to those born for such work.
The energy market is vast, and investment capital abundant. There are always a few doubters, losers, or complainers in any emerging tech sector, no matter how good things are.
AWE’s prognosis only gets better, since the tremendous upper-wind resource has hardly begun to be tapped, and there is no insuperable barrier in our way.
Thanks Pierre, AWE is the greatest new tech field.
Reviewing this thread, the pessimism seems based on not knowing how much AWES art has been explored. KiteLab Ilwaco made a sled-kite laddermill, and kPower Austin made a soft-drogue under a pilot-lifter variant. Its not hard too make a toy laddermill at least. Anyone who wishes can inspect, test, and/or purchase the prototypes, or just make their own versions.
Pocock and Culp both pulled large vessels (small ships) by kite before kitesurfing was developed. Then came pulling larger ships by kite, by both KiteShip and SkySails, and now Airseas. Its been done for almost two centuries, with multiple circumnavigations and uncounted ocean-crossings, and now being adopted by Airbus for its fancy delivery ship.
Those who fear AWE is too hard overlook a lot of prior art.