Yes, I was trying to focus first on the "enthusiastic individual" who just needs minimal support to make progress.  Grant-writing is a serious distraction.  Serious psychological tests show that large monetary rewards actually stifle creativity.  Let's see how far we can get with the economy team in their garages.  The greater the talent, the more it is self-rewarding to exercise, if unhobbled.   A policy of paying for novel research and making it freely available for building upon should eliminate a huge amount of redundancy.  Perhaps a forward-thinking government could tackle projects like summarizing our own archives and making the resources easy to navigate, without introducing much bias.  Google isn't enough.

interesting to see the team names behind this. Well cool gadget Pete,
Saul and otherlabs. not sure it's ready to climb up a kite yet. but cool
and useful none the less.
www.newscientist.com/mobile/article/mg21528735.300-what-its-like-to-ride\
-an-inflatable-robot.html

Even by taking "mobile" out of the URL, I can't get anything.

After seeing JoeF's June 29th AWES posting about air beams, I patched together photos of the first model of the "tubeboat" design type, along with a later design development idea sketch. 

The Tubeboat59.0 model shows only the semi-hard lifting body hull, and the semi-soft hoop mast. Both components are to be pressurized and shape adjusted on the fly, to help maintain optimum attitude control. Not shown on the model are the rotor disks (vertical axis) & the more solid body, wheels/flying disks (mostly horizontal axis) that operate in a similar fashion to the September 25, 2000 design posted at http://flyinground.com/  (see Jun 28 2012 posting).

Even less related to the original posting topic, but generally related to soft inflated bodies, fluid dynamics, and environment based structural development, & I think is a must see for kiters, is this great video by KQED QUEST called "Amazing Jellies" http://www.youtube.com/watch?v=pimIbTqJLZc&feature=em-share_video_user  . Someday kite arrays in the upper atmosphere may evolve with lessons learned from jellyfish colonies. 

OK Joe,

 

Here is a little something*:

http://youtu.be/RE3GEEDd0AI for seeing a better presentation of the wind energy module for FlygenKite.

 

PierreB

http://flygenkite.com (photos on the page "products")

 

*By soon I can give some elements for another method for great production.

Something of interest for the group.

http://networkedblogs.com/AgLoY

Lots of interesting ideas on the forum.

All of these energy generating solutions need a control system (robot), otherwise they will end up on the shelf or in the bin.

There used to be a show on TV called "Joe 90".
The basic idea was that a young boy (Joe) sat in a machine that implanted the technical experience of an expert into his brain. After this transformation, he could do everything that the expert could.

So, there are many expert kite flyers - whose expert ability needs to be implanted into a robot.

In order to transfer, this 'knowledge' into a robot, a mechanism is required to link the person to the machine.

There is a sensor called 'kinect' (used for game playing) that can capture the movements of a person in 3D space.
So, someone holding 2 kite poles can fly a kite (no lines), and all of the pattern data can be recorded in a database.
This pattern can be replayed by the robot.
Infact, the person can fly the robot in real-time, and the pattern recorded simultaneously.
So, the person can see the kite as normal, but it is the robot's winches and lines making the physical connection, and the person holding the free poles and creating the movements.

The power generated by a pattern can be calculated (e.g. using the wind doctor), and by allowing the robot the 'ability' to adjust certain parameters and replay the pattern, it can achieve the best power output for the weather conditions.

This system is demonstrated in the video.

http://www.youtube.com/watch?v=Ma7tDKl97NQ&feature=plcp

Derek,

Glad to see there is someone else in this group convinced that computer
control is essential for progress in AWE. Did you write the Wind doctor
and kinect software yourself? visventis.org will be needing this sort of
thing soon so I will be watching your progress with interest.

Robert.

Derek , I do think you will get a fantastic solution to carousel control
with robotics.
And well executed it will be a powerfully efficient machine.
I was pulled across the water by a 17.5kW pulley line today.
Hannamswakehub.com
It wouldn't take much engineering to convert that same system to a carousel where the cables drive the pulleys.
However there is quite a lot of monitoring and control required to keep multiple kites
Driving a machine like that.
Once I get round to testing my ring thing, I'm planning to get involved in carousels with robotic gondola too.

Awesome work share. Thanks
Roddy

So excited for you guys. Winds be with you Dave.

Robert & Roddy

I've seen your videos also. Building small prototype systems is the way to go. Practical demonstrations will push the technology forward.

Yes, the 'wind doctor' is free software to monitor the performance of your system. It can log data to disk, and display real-time
power, voltage, amps, rpm etc via charts, as well as plotting power curves ...

Derek

This is the best news I've seen on the tech lists in a long time.   It also validates Bucky Fuller's faith in tension structures.   Three Cheers for Dave and each team member.  

Congratulations Dave Santos.

 

"...landing and launching with consistent tameness, including usefully "tail-sitting" on its single central spar":a way towards passive control including landing and launching.

 

PierreB

This technology could be the game changer for AWE. Both ways.

http://www.popularmechanics.com/technology/aviation/news/how-it-works-laser-beaming-recharges-uav-in-flight-11091133?click=pm_news

WOW !

---

 

Some moths are happy flying bumping into hot lamps.
This moth has sent joy round the world, reaching for the moon.

mk wrote on 4.1.2012:
There was one of these on the BP kite traction research boat "Assessor" last
owned by the late Air Commodore C T Nace in Cowes. Any info on its use would be
available from Roger Duckworth, former kite researcher for BP.

Theo Schmidt

Another useful explosive might be,
using remotely activated airbag style inflation for structures to be inflated at altitude.

The arch has an interesting configuration for energy conversion with its two legs:alternating power can consist into strokes on one leg then the other,power on one leg and half arch while depower on the other and the other half arch,so continuous power.

 

PierreB 

The HQ Hydra  also has interesting relaunch characteristics borne from a neat construction method.

A permeable leading edge acts like a standard ram air kite, until it feeds air into cells which close when inflated.
 
The same construction idea could surely be used / modified to suit other rigid inflatable components as required.

http://www.powerkites.de/index.php?option=com_video&view=video&video_id=16&Itemid=129 

Kitelab's experiments and explains about "passive control" and "inherent
stability"are a good lever for further analyses.So here are some
thoughts or questions:

-Has a really good potential for self-launching if _ due to the
necessary long tether for AWE _ unwind and roll-up operations are taken
into account (exepted maybe for offshore)?If no the occupied ground
space is huge.

-On the contrary arch has a good potential for self-launching and
(because) no length of only rope,but for harnessing high altitude
winds,about 300 meters in altitude (for example) the arch must be
something like 1000 meters wide and 150,000 m² kite area.So in the
end the occupied area for dominant winds is 0.3 km²,and for all winds
above 1 km²,for a potential about 5 MW or less with wind speed = 12
m/s.

So systems with "active control" ("control computerized by servos" with
addition of equipments) can be prefered because of other parameters
following configurations allowing "passive control".

More I look towards AWES for massive production more problems for any
configuration seem insuperable...

PierreB

--- In AirborneWindEnergy@yahoogroups.com, dave santos <santos137@... ****Oil may never be cheap again, since new extraction techniques use more oil, to get oil out of the ground, and China is now building more cars per year than the U.S., keeping demand high But oil is mostly irrelevant since it's natural gas and nuke plants, hydroelectric, geothermal, and lately even solar, that wind energy competes against. Major power plants are not fueled by oil for the most part. So oil prices are largely unrelated to wind energy****

The silver lining for AWE R&D is the collapse of those ventures based on tech hype and�the hope of easy "windfall" energy profits. Some groups will�linger on military life-support, but don't expect�hot products to emerge directly from mil-spec culture. What's left is the core community of dedicated AWE�developers who love and understand kites and are happy to incubate the future in nice niche markets.

****Unless success in AWE does not involve kites, in which case this entire line of reasoning would be irrelevant. How many years do you want to "incubate"? We've heard all the "superior" theories and predictions... Why no working products yet?****

****Nickel electricity is the challenge wind energy faces every day - I mean the actual art of wind energy that has to fit into the real world. Don't forget the supposed reason for AWE is to economically outperform the existing art. Well-funded wannabe innovators often target only industrial-scale solutions, since the perceived impossibility of creating them forms an excuse to waste everyones' time and investment money for years without a useful result, while yet maintaining a plausible story. If they had to create power for a single house, and failed week after week, transitioning to months and then years, with still no home powered by AWE, they'd more quickly be flagged as having no idea what they were doing. The large scale has a built-in intimidation factor that ceartes a degree of doubt that serves to obfuscate a lack of a truly workable solution.

On the one hand they say "We HAVE to compete with big wind to realize the economy of scale to make it meaningful" yet on the other hand they say "you can't POSSIBLY expect us to compete with all these bigtime experts who actually know what they are doing! - there;s no WAY we could EVER compete with the simple requirements of the existing wind energy industry." I say "pick a lane" - if you want to wallow in an endless, open-ended, perpetual excuse-driven fantasy, at least make your excuses line up so they are not self-contradictory*****

****If I even had a few weeks of spare time I could have a working system in the air. Several months could have many types of working systems in the air. There is nothing stopping anyone from making working AWE systems right now except either laziness or having no idea what they are doing, starting with no knowledge of wind energy. There are no technological barriers at all. Working systems can be constructed immediately using off-the-shelf components. Anyone purporting to be developing AWE that has demonstrated no working system simply has no excuse. And as we know, the most important thing in this modern, virtual lack-of-a-world is to have "an excuse". Reality: missing in action *****

Fortunately for AWE developers, existing�market nickel-rates are the rare extreme, and the average�world market�cost is far higher. Energy costs ten times higher,�or more, are common. High energy excise taxes are common.�Low�US regional�rates are an anomaly; Hawaii pays forty-two cents,�which this is not out of line with many advanced economies, like Japan and�some EU countries, who increasingly shun the hidden (steal-it-forward)�cost of nukes and unhappily�import fossil fuel to keep the lights on. The developing world has some of the highest rates of all. In the Solomon islands, electricity costs over eighty cents a unit. Many a remote valley or island is in the same situation, with no electrical infrastructure and astronomic diesel-electric costs. High-cost electrical markets are vast enough for any small AWES developer to carve
****Fine then, show us your 50-cent/kWh solution. You're right - there is a market for it. Just not a typical Wind Energy Utility-scale PPA in the U.S. On the one hand you hear the AWE innovators say their systems can only compete at a utility-scale, (excuse #1) and that in fact the MAIN REASON for AWE is that it CAN be done cheaper that existing wind energy systems, but then the next AWE innovator says meeting the same utility-scale costs as existing wind energy is impossible. (excuse #2). Excuses #1 and #2 are mutually contradictory. If you have a 50-cent/kWh solution, yes there's a limited but definite market. What are you waiting for?****

****Decent, reliable wind energy solutions are routinely implemented at various COE levels depending on location, cost of competing energy sources, and budgets. It's not hard to find great markets for reliable small wind energy systems. It IS hard to find the actual reliable systems however... If you had one, there would be no trouble finding buyers. key words: "energy" (not empty words) and "reliable" ****
**** Yeah I think I heard that somewhere before. I can think of about 10 simple ways to harvest it but don't see anyone identifying them, much less pursuing them. Well you have one thing right: repeating the name Doug enough times is the magic solution to AWE. keep repeating my name and maybe you'll get something working*****

Good riddance to carpet-baggers who jumped into AWE R&D, rode on hype,�and now are now�slinking out.

****Easier to fixate on the perceived failure of others than to make progress yourself. I'd forget about what others are doing and if you have something that works, get it out there!****

The�smartest toughest�industry survivors are banding together and will thrive- slowly...

****Wow whenever I hear of another team with no current solutions, with promises to revolutionize the wind energy industry, announcing how "smart" they are, I say "Oh boy, more "smart" people. SO far I have not seen one such team come up with anything except telling everyone how smart they are then never coming up with a workable solution at all. You can quote me on this: "If you have to tell people how "smart" you are, you probably aren't."
When you are smart, the evidence speaks for itself. Better to let others remark how smart you are, after seeing the evidence, than to announce your own smartness in advance of, or in lieu of, any evidence. ****
:)
****Doug Selsam*****

Adversaries No More: The Defense Department's Mighty Wind Energy Plans
by Mark Del Franco, Aug. 7, 2012 email the content item print the content item
Ever since the earliest turbines were installed in California in the 1980s, the U.S. Department of Defense (DOD) has had an unfavorable view of wind energy, as wind turbines interfered with radar systems. However, thanks to new technology and a recently announced collaboration, the DOD is set to become a [read more]

Lockheed Martin (logo displayed) ****(AWE "player" - ha ha ha - a real knee-slapper - together with NASA they collectively have nothing - what's stopping them?)****

Obama Expedites Seven Massive Renewable Energy Projects
by NAW Staff, Aug. 7, 2012 email the content item print the content item
President Barack Obama has called for seven renewable energy projects - including two massive wind farms - to be expedited. The projects are located in Arizona, California, Nevada and Wyoming, and have the potential to produce nearly 5 GW of renewable energy and power approximately 1.5 million homes, according to [read more]
Otter Tail Putting Wind Tower Manufacturer DMI Industries Up For Sale
by NAW Staff, Aug. 7, 2012 email the content item print the content item
As part of its second-quarter earnings update, Otter Tail Corp. has announced that it is selling wind tower manufacturer DMI Industries for $20 million. Otter Tail entered into a non-binding letter of interest in June to sell DMI's property, plant and equipment for $20 million, with the corporation retaining DMI's [read more]
New York Senator, Clean Energy Advocates Push For Better Net-Metering Law
by NAW Staff, Aug. 7, 2012 email the content item print the content item
Sen. Charles Schumer, D-N.Y., and members of the Alliance for Clean Energy New York (ACE NY) are calling for improvements to New York's regulatory mechanisms for on-site renewable energy generation, placing particular emphasis on the need to raise the limits on utilities' net-metering programs. New York's net-metering law allows customers [read more]
Work Begins On 288 MW North Sea Offshore Wind Farm
by NAW Staff, Aug. 7, 2012 email the content item print the content item
WindMW GmbH, a joint venture between Blackstone and Windland Energieerzeugungs GmbH, says it has begun construction on its 288 MW Meerwind Sud Ost offshore wind farm. The 80-turbine wind farm is being constructed approximately 50 km off the German coast in the North Sea. The wind turbines will be installed [read more]

Momentive Specialty Chemicals
Vestas Wind Turbines To Dot Landscape In Tuscany
by NAW Staff, Aug. 7, 2012 email the content item print the content item
Vestas says it has received a 19.8 MW order from Santa Luce SRL, a special-purpose company of Fera SRL, for 11 V100-1.8 MW wind turbines. The turbines will be installed at the Santa Luce Wind Power Plant, to be located in Italy's Tuscany region. The contract comprises the delivery, transportation, [read more]
LM Wind Power Announces U.S. Layoffs Amid PTC Uncertainty
by NAW Staff, Aug. 6, 2012 email the content item print the content item
Wind turbine blade manufacturer LM Wind Power has announced that it is laying off 94 employees and 140 temporary workers at its Little Rock, Ark., manufacturing facility. The company cited the U.S. government's failure to extend the wind energy production tax credit (PTC) as the reason for the layoffs. "We [read more]
Massachusetts Governor Signs Clean Energy Legislation
by NAW Staff, Aug. 6, 2012 email the content item print the content item
Massachusetts Gov. Deval Patrick has signed S.2395, legislation that contains several clean energy provisions. The new law includes the extension of long-term contracts between utilities and renewable energy companies - a measure the governor's office says will keep the supply of renewable energy credits in balance with the growing demand [read more]
Fire At Hawaii Wind Project Site Destroys Energy-Storage Building
by NAW Staff, Aug. 6, 2012 email the content item print the content item
A fire broke out Wednesday at an energy-storage building that is part of the Kahuku Wind project on Oahu's north shore, Hawaii News Now reports. According to the report, the fire started Wednesday in the battery storage building, which is now destroyed. The wind project uses an energy-storage system from [read more]
GE Acquires Stake In 200 MW Prairie Rose Wind Farm
by NAW Staff, Aug. 6, 2012 email the content item print the content item
Geronimo Wind Energy has sold its 200 MW Prairie Rose Wind Farm to its partner, Enel Green Power (EGP). Subsequent to the purchase of the project, GE Energy Financial Services acquired an ownership interest in the project from EGP. The GE unit now owns 51% of the project. Enel Green [read more]
Construction Begins On 400 MW Global Tech I Offshore Wind Farm
by NAW Staff, Aug. 6, 2012 email the content item print the content item
Windreich AG has announced that construction has begun on the 400 MW Global Tech I wind farm, which will be located in the German North Sea. The project will consist of 80 AREVA Wind M5000 wind turbines with an output of 5 MW each. The floating Alstom substation will be [read more]
Gamesa Sells Polish Wind Farm To RWE Innogy
by NAW Staff, Aug. 6, 2012 email the content item print the content item
Gamesa says it has completed the sale of the Taciewo wind farm, which is located in the Podlaskie region of northeast Poland, to RWE Renewables Polska, a subsidiary of German power company RWE Innogy GmbH. The transaction marks Gamesa's third sale in a year and a half of a Polish [read more]
Pharos Completes Cable Repair On London Array Offshore Wind Farm
by NAW Staff, Aug. 6, 2012 email the content item print the content item
Pharos Offshore Group says it has completed the repair of a section of damaged subsea export cable at the London Array Offshore Wind Farm. The company provided the engineering, fabrication and operational teams to locate, recover, re-lay and re-bury the power cable off the Kent coast. The 800 square-millimeter HVDC [read more]
Senate Committee Passes One-Year PTC, ITC Provisions
by NAW Staff, Aug. 3, 2012 email the content item print the content item
The U.S. Senate Finance Committee passed a $205 billion tax extender package as part of the Family and Business Tax Cut Certainty Act of 2012 that includes a one-year extension of the wind energy production tax credit (PTC) and the investment tax credit (ITC). The Family and Business Tax Cut [read more]
To Help Meet RE Target, Nova Scotia Approves Three Wind Farms
by NAW Staff, Aug. 3, 2012 email the content item print the content item
In an effort to meet its renewable energy target of 25% by 2015, the Nova Scotia Department of Energy has announced it is moving ahead with three utility-scale wind projects that are expected to bring $200 million in new investment. The three projects include the 78 MW South Canoe Wind [read more]
New Mexico Clean Energy Standard Filed At Public Regulation Commission
by NAW Staff, Aug. 3, 2012 email the content item print the content item
A consortium of New Mexico organizations has petitioned the New Mexico Public Regulation Commission (PRC) to force state utilities to reduce their carbon-dioxide (CO2) emissions by 3% per year. According to New Mexico-based New Energy Economy, more than 30 New Mexico organizations, representing business, consumer, Native American, environmental, health and [read more]
NextEra Sells Wind Project To Wisconsin Energy Corp.
by NAW Staff, Aug. 3, 2012 email the content item print the content item
NextEra Energy Resources has confirmed it is selling the 30 MW Montfort Energy Center to Wisconsin Energy Corp. for $27 million. The 20-turbine wind farm, located near Dodgeville, Wisc., opened in 2001. The energy will be sold to Wisconsin Power & Light and We Energies, according to a company spokesperson. [read more]
Ex-Im Approves $32.1 Million In Financing For Export Of U.S. Wind Blades To Brazil
by NAW Staff, Aug. 3, 2012 email the content item print the content item
In line with its congressional mandate to increase support for renewable energy exports, the Export-Import Bank of the U.S. (Ex-Im Bank) has authorized a $32.1 million loan guarantee to Brazil-based Wind Power Energia S.A. for the purchase of wind turbine blades manufactured by Little Rock, Ark.-based LM Wind Power Blades [read more]
Congressman Sponsors Bill Meant To Spur RE Investment
by NAW Staff, Aug. 3, 2012 email the content item print the content item
U.S. Rep. Bob Filner, D-Calif., is sponsoring the Clean Energy Victory Bonds Act of 2012 (H.R.6275), which would enable the continuation of the production tax credit (PTC) and other clean energy incentives for 10 years. According to nonprofit Green America, the bill would extend the PTC and other proven federal [read more]

Eagle West Wind - General Manager, Operations & Maintenance

NREL - Wind Deployment: Supervisor-Manager II, Project Leader


To place an ad within WindJobs, contact Dave Mendelson at 1-203-262-4670 x248, or at mendelson@nawindpower.com

Link to Story:
http://www.treehugger.com/wind-technology/new-bladeless-wind-turbine-claimed-be-twice-efficient-conventional-designs.html

Experienced Wind Energy People can easily flag the story below as nothing but complete unadulterated balderdash - others may find it convincing. It all comes down to whether you
a) know anything about wind energy
b) have a built-in bullshizzle detector

Note: they give almost no details except that it costs half as much and generates twice as much as the status-quo, so that means 1-cent/kWh, right?!

(I'll bet they are also "smart!")

http://www.treehugger.com/wind-technology/new-bladeless-wind-turbine-claimed-be-twice-efficient-conventional-designs.html

http://www.energykitesystems.net/Fun/LifeOnMarsCURIOSITY.jpg 

:)
PM

Doug wrote:
I wouldn't dismiss it that easily, even if I expect conventional wind generators
work better. The questions are: do pure drag devices (which also includes static
kites) work more or less efficiently than lift devices (turbine blades, dynamic
kites)? What is meant by efficiency? Is the Betz limit circumvented, as the
website claims?

I don't know the answers for turbines, but I do for propellers. Here a pure drag
device can in theory be more efficient than a lift device, but in practice it is
usually the other way around. A drag propulsor can approach 100% efficiency by
making it big enough. Imagine a large parachute deployed in water: you could
winch a small boat toward it with almost 100% eff. - until you get there. The
best propeller imaginable wouldn't exceed 98% however, do to unavoidable losses
expressed in the maximum L/D ratio of the blades. In practice it is probably 95%.

I assume for extracting energy from a fluid stream much the same applies. An
extremly large drag device (e.g. huge, buoyant kite) would couple almost
perfectly to the fluid stream, better than a turbine with its unavoidable
losses. Imagine an airship drifting with the wind. If you attach a line and
power a small generator, you get some power with almost no "slip" of the (large)
airship; i.e. it won't notice or slow down. Inverse slip is however an
efficiency figure: you are extracting power from the air stream approaching 100%
efficiently. With a stationary or buoyant turbine you might approach 98%.

This has nothing to do with the Betz limit, a figure representing how much of
the stream's kinetic energy you can extract, not really an efficiency. I guess
the only way to exceed the Betz limit would be to completely capture a parcel of
fluid and completely bring it to a standstill. Wrapping up the entire wind with
a gossamer sail, as it were. In a sense, this is what a sailboat's spinaker or
Dave Culp's giant kites do: the airstream trapped "inside" the device is brought
to a standstill, its kinetic energy entirely converted. Now the rest of the wind
escapes around the edges, so you would have to make it ever bigger, in the limit
wrapping up the entire wind available, bringing it to a standstill, and then
"releasing" it to start a new cycle. A turbine can't do this: it must have part
of the stream going through it. In this sense the website may be correct:
theoretically a sail can overcome the Betz limit a bit more than a turbine. (I
may have this all wrong, however.) However in practice I don't think the device
shown can be more powerful than a conventional turbine of the same size,
probably the opposite. It might be quieter and less dangerous, however.

In practice it mainly boils down to the cost of intermittent versus continuous
movement, which we keep discussing. Given the inherent low cost of a drag
surface compared to a lift surface, there is no basis for discounting the
website's claim on principle, even if practice so far seems to indicate a lower
cost for lift technology.

Cheers, Theo

See the motion of the drag body at 3'5'' on  www.youtube.com/watch?v=WdcmShRcyfk  that the patent WO201209688 (with a good search report without x or y) indicates as "circulate sattelite movement". Behind the drag body there is also a reel with... small blades which surround the drag body.The blades  are not schown on other pictures,and are maybe put off as not essential or ... bad for the definition of a turbine without blades. 

If I am yet nastier than DougS [In fact Doug is not nasty but realistic most of the time,and probably gives a better way for AWE by indicating like autogiro scheme as link between wind turbine and aviation],I could think wind energy on the blades produces body movement.

But I prefer thinking patent from Saphon describes a new method as drag device to produce conversion with some interesting elements of conversion like hydraulic installation [see also OrthokiteBunch where hydraulic installation works from movements of big amplitude compared with the limited movement of drag body implying probably a low efficiency in conversion],which could be studied and implemented for AWE at the same time as a "circulate sattelite motion" but with enough amplitude.

The ideas in this patent have probably a better possible outlet in AWE since some mechanic elements allowing "circulate sattelite movement" could be put off. 

"Circulate sattelite motion" is a little like DaveS' short strokes.If it is the case and if a good drag conversion system is found a low efficient system can become a high efficient system where low cost great area like arch is implemented.

PierreB   

 

 

Hi Theo:
Thanks for a well-considered response. Though you put a lot of time and effort into thinking about it and expressing a resulting opinion, the result indicates a lack of knowledge of wind energy fundamentals. The Betz limit is real - as real as anything gets. It has to do with removing air from the turbine area some more can get in. To remove that air, that air has to move, and that movement contains kinetic energy. That means some of the kinetic energy must be left in the air so it can leave.

Think of your turbine as a movie theater: the idea is to bilk the customers of as much of their personal worth as possible, while they waste their lives away sitting in a chair in the dark, doing nothing but absorbing whatever twisted ideas you can thus pump into their feeble brain for 2 hours. Then at the end of 2 hours, you NEED those people to LEAVE the theater so you can bilk the next batch of idiot mind-control victims. "Get out of here!" you say. "It was just an illusion! The whole story was just made up! Photons on a screen! No you did not have sex with Jennifer Aniston! And your mate is still pissed - taking her to the movies didn't work. Now get over it and leave!"

Got it so far? You're in show biz. Glamorous enough for you yet?

OK now imagine you extracted ALL of the foolish victims' net worth while they sat in the dark, obediently, quietly, doing absolutely nothing for 2 hours: you drained their bank accounts, their gas tanks, even removed their clothing and shoes while they weren't looking, and took the tires off their cars in the parking lot and sold them.

Now how's your movie theater doing? Not so well? What's the problem? What, nobody will leave? Bbbbut I thought you WANTED lots of people in your theater! Oh wait, you're telling me it's not how many people you can cram INTO your theater, it's how many people you can get to flow THROUGH your theater! So you're saying it's just as important that people LEAVE as that they COME, or else you can't have a FLOW of people through your theater. OK I get it. SO getting RID of your USED people is as important as getting NEW people INTO the theater eh?

AAAAaand you found that the only way to get the people OUT was to not take ALL their net worth, so they still had shoes to walk out, still had a working car in the parking lot with gas in the tank, still had a home to go to, so they didn't need to sleep over on your theater floor - is that it?

Year later a theater owner named Betz quantified it:
You can take a theoretical maximum of 59% of the customer's spending money for that night, which leaves them just enough money to leave the theater and get home again, eat, make their car payments and house payments and clothe themselves, so they can come back and waste away the next night, and the next, and the next....

Even with this information, a prospective theater-owner named Theo Schmidt yet persisted in what he thought was a radical new business plan for theater-owners worldwide:
Use a net to capture all the people coming into the theater, whereby the owner can first trap the hapless patrons, beat them to death, take everything they own, and then... - well hey with a plan that good, who needs to consider the next step? Anyways... after a fashion the other theater owners began, quite properly, ignoring everything prospective theater-owner Schmidt posted on the web, saying "Schmidt needs to read a book on basic theater-ownership 101" not to mention how to treat a guest so they don't understand they have been ripped off - maybe he should attend the School of Hotel Management at Cornell - I'll bet the cover this sort of stuff".

Disneyland has the Betz coefficient down: extract all of a family's net worth while they are in town, except leave them just enough to get home and restart their lives, so they can come back again next year.

So yes it is that basic.
Then you can add all the parachutes and reciprocating cycles you want but it never changes the basics of show-business: the customer has to leave so more can come in, and he can't leave if he is broke, so you can't have a theater that takes all of peoples' net worth or they will stay and sleep on the floor and you won't be able to charge any more customers admission.

So.... "Betz doesn't apply to drag devices", and "reciprocating cycles are the answer to wind energy"... geez have I ever heard a newbie make those statements? Oh wait - they ALL make those statements! Those two statements are what DEFINE a newbie! They are SYMPTOMATIC. (are you listening NASA?) And yes we all started there - thinking that same thing, some of us when we were little sproutlings. Then we learned to read...

Theo, unfortunately without any background in wind energy, no matter how many words you put on the page, none of them means anything. You might as well be talking about Jennifer Aniston as wind energy. There is only one answer: you need to read a couple of engineering books on wind turbine theory and design. Then you can start to have a meaningful discussion about wind energy. Otherwise you just sound like an amateur, making typical amateur incorrect observations, and resulting false assumptions. Theory based on false assumptions is meaningless.
:)
Doug Selsam
See title of posting for complete info

--- In AirborneWindEnergy@yahoogroups.com, Theo Schmidt <theosch06@...