If you know what you're doing, do it.

All:

A handful of minor errors and nuances have been corrected or noted in my post based on comments left on my blog or communicated via email.

1. Dr. Rolf Luchsinger of EMPA and TwingTec pointed out that TwingTec uses dual tethers, not single; I've corrected that. He also indicated a less than doubling of tether drag with the use of dual tethers, but it remains unclear to me why or how this could be based on the math and physics involved without a reduction in velocity, so I've left that alone at present. 

2. Dr. Roland Schmehl of UDelft provided reference to the AWE book and graciously offered chapters to those interested, for which I've thanked him.

3. Dr. Mark D. Moore of NASA pointed out the weakness of my final viability analysis chart compared to the rest of the analysis, and I agreed completely. That final viability table is intended to be comparative from an informed perspective not deeply empirical and I've noted that more clearly in the text. He also brought up the interesting subject of low-level jets, which didn't seem substantive to me. At present, many ground-based wind farms take advantage of geographically focussed -- valley exit and mountain side -- low-level jets, ground-based wind turbines already clear sheer in many cases and winds aloft nightly jets are not ubiquitous. The sheer boundary creates its own challenges for AWES, especially but not uniquely soft wings, so while it's an interesting topic, it doesn't appear to me to change the fundamental discussion of design compromises between AWES. As I move through revisions of the viability chart, I may address this further, but at present I've left this alone.

4. Dr. Andrew Wagner of KU Leuven shared some useful insights on Makani's progress, none of which contradict the material I'd put together. He agreed that durability and maintenance cost are big unknowns. Nothing in his response led to changes in the material, although the conversation may continue. I've asked for his thoughts on my Makani analysis.

5. Dr Allister Furey, CTO of Kite Power Systems points out maintenance of devices could be via hot swapping, but I had considered this in my Makani deep dive which informed this material. Hot swapping requires more onsite staff, more onsite storage and more investment. I haven't seen an analysis of this, but I've dealt with asset maintenance and optimization programs as part of my career in other industries. This is non-trivial, and my concern regarding airborne systems remains unchanged. Dr. Furey also pointed out that computation in the air required slightly less than smartphone levels of smarts and power draw, but upon review I don't believe that changes my point regarding single tether devices where it is most pertinent, so I left those comments unchanged.

6. It's been noted that Sky Windpower may have abandoned plans for high-altitude generation. However, as of November 3rd, 2013, all publicly available material on their site still focused on high-altitude generation, its advantages and their plans to harness it. As such, I've left Sky Windpower's positioning alone, with the note that anecdotally Sky Windpower may have abandoned high-altitude wind generation. If Sky Windpower's public material changes, of course I will mark my analysis and position as historical, and consider alternative high-altitude solutions to assess.

I would again encourage those of you with substantive comments to comment on my blog or email me at mike@barnardonwind.com. 

There has also been some murmuring about a debate. If I am approached by a credible representative of the AWES research or corporate community with a proposal for a public discussion, I would gladly discuss this interesting topic.

Thank you all for your past assistance in understanding AWES better, and to those of you who have provided substantive comments on this latest material.

Cheers,

Mike Barnard

barnardonwind.com

mike@barnardonwind.com

Doug Selsam's Super Twin at Wulf Field

"Energy potential increases for onboard generation with turbine blades with the cube of velocity of air, so rigid wings such as Makani’s approach have significant potential advantages."
(It is a minor point for a light improvement). The conversion by onboard turbine blades goes after the conversion by (here) rigid wings which advantages go towards Makani as well as Ampyx (the rate of power should be the same _ like suggests Dr.Allister Furey _ until differences of average power becomes obvious between ground generation (Ampyx) and onboard generation (Makani)).

Concerning the debate. Why not with editors of the Springer book of AWE?

PierreB

MikeB,

Correction of my precedent message... "like suggests Dr. Andrew Wagner" (not Dr. Allister Furey).

PierreB

DaveS:

Dr. Mark D. Moore's comment in its entirety is included without edits on my blog page. No censorship exists. Anyone can check that. No censorship has been applied to any comments on my post.

Except to any comment you might have tried to make. The only censorship that has been applied to anyone in the AWES community on my blog is to you specifically DaveS, because you've proven yourself over an extended period to be a low-content, vitriol-spewing moron who couldn't present a reasoned and consistent description of an airborne wind generation solution to save your life. When I left this group due to the signal-to-noise ratio, you were the specific cause. You are noise, and as far as I can tell, nothing but. Similarly, I have killfiled your email address so that I don't have to put up with your noise in my mailbox.

And here you are accusing me of censoring Dr. Moore and others when their comments are as submitted on my blog without any changes.  I just choose not to listen to you in any forum, and not subject people to your drivel on my blog. Oddly, that's my right. You have the rest of the internet to be ignorant on.

Your continued nasty, baseless attacks on me are, I'm sure, obviously false and without merit to others on this forum. They know you after all, and I continue to wonder why you are tolerated.

In the face of your overwhelming bullshit, I've tried to be polite. As others pointed out to me privately, you are like toxic waste; no one should take it personally. However, like toxic waste, you should be cleaned up.

I've attempted to provide polite and reasoned material that while skeptical, is not personal and is fact-based. I've welcomed reasoned, referenced and intelligent discussion of the material, and adjusted it as errors are pointed out. I've reflected back the changes, acknowledging where I made errors. 

You make reasonable discussions impossible DaveS. That's why I'm no longer on this forum. That's why I've blocked your emails and banned you from commenting on my blog. You have no value to contribute, just noise.

The reason I have been silent on a suggested debate is because I only saw Paul Gipe's reply. If you copied me on the email, it went straight into the garbage. And now that I have seen it, I wouldn't consider a debate at all because you proposed it and are promoting it. There is no reasonable, useful discussion to be had in which you are involved.

To others on this forum, my apologies. I'll sign off again. Please consider everything Dave Santos says about me to be ignorant speculation and lies. I welcome discussions with the rest of you.

Cheers,

Mike

On front page of Upper Windpower, the online AWE Book:

 The Great AWE Debate: Mike Barnard is invited to have his team debate in public over AWE kite-energy issues. 2014 and beyond. He is invited by the editors of Upper WindPower to participate with his team. Just how the debate will be handled is being drafted.  Anyone skilled in forming debate platforms?

There is a difficulty; the CTO of KiteLab Group and kPower, Inc. must be addressed fairly in equitable treatment as members of teams on all sides of the Great AWE Debate.   Personal attacks are outside the debate run; staying on non-personal related issues will go a good distance in obtaining value for the world from the debate. Similar respect for each participant is highly invited. 

 Time to Break Free of Net-Metering; We Need a “FIT” Policy for Renewable Energy to Soar

Posted by Paul Gipe on  December 26, 2013

  Airborne wind energy: a collection of challenging compromises  by Mike Barnard is an important contribution towards a better knowledge of the viability of Airborne Wind Energy. The responses are all interesting and point of technical elements, sometimes instructive critics like from Dr.Mark Moore considering also Barnard's article as a basis of work. The general tone of comments written by some of major players is an indication of the validation of the article:only arguments, no personal attacks, no yellow journalism. It is a positive thing a journalist in general wind energy details AWE .

Some questions stay: High Altitude Wind Energy is a huge resource. AWE is a field of researches from only some years, even if some description exists far before, even if hundred patents (with no effective applications) exist. So one way is considering AWE as inherently no viable; another way is considering AWE as not yet mature; probably a mix between these ways.  So further debates will allow to see what can be improved (materials, automation, tethers, resistance of wings regarding UV, better schemes than tried schemes,a better knowledge of possible and advantageous (offshore) locations for implementation...), and what cannot be (level of reliability, land and space used...).

PierreB

Offer: stay off from cementing untouchables: 

   Pierre noted some kind of abandonment, it seem: "and what cannot be (level of reliability, land and space used...)" 

Rather: keep growing improvements in reliability, effective land use, and dense use of space. No need to bury an effort on these parameters. 

 JoeF

That is a neat suggestion.  Consider, though, setting the tentification downwind some in the wake field of the conventionals, as the meters on the conventionals are going to be stunted on performance by the involved works. Both, perhaps; as shown to test also the effects on the meters; and then further back in the wake field for further testing. Data should be helpful to all camps. [Hello, John Dabiri ?]

JoeF

The part of (level of reliability, land and space used) which is inherent after improvements.
A little like the part of the weight of tower which is inherent _ after improvements _ in conventional wind turbines.

PierreB

DaveS,

On this message only utility-scale is considered.You critic a lot of schemes like Makani's and others, and you are right concerning technical features. Doug critics all AWE schemes (excepted Superturbine), and he is right (perhaps excepted for Superturbine). By joining your and Doug's critics one obtains a general AWE position like Mike Barnard' and also Paul Gipe' thinking there is no next future for AWE (that means Paul Gipe and Mike Barnard do not exclude the possibility of a long-term viability) , and I agree, thinking none of prototyped AWES taken alone can evolve towards viability. No next future (see my comments on Airborne wind energy: a collection of challenging ... - barnard on  ) is an opening towards two possibilities:AWE is inherently non viable; AWE is non viable for years until a better concept is realized. I choose the second possibility, agreeing with Dr. Mike D. Moore for building genetic material towards solutions which are now not directly predictable. A specifications should be built before making a design.

So it is quite possible MikeB's article works as a second step towards a really viable AWES.

PierreB  

New support page: 

http://www.energykitesystems.net/DanHunter/index.html

which has also a link to Goodall's microwave from AWES to ground patent. 

=========================

Hunter is emphasizing "long" low-frontal projection aerostats. 

Proving Prandtl- With A Twist!