Talk:Solar updraft tower/Archive 2

message: I'd suggest not to move discussions there until they have run their course, and any relevant question has been answered. Thanks --Singkong2005 tc 02:28, 17 July 2006 (UTC)

message: EnviroMission Ltd Australia owns the exclusive license to German designed Solar Tower technology in Australia while H. Alfred Goolsbee owns the Japanese trademark and service mark "Solar Tower". H. Alfred Goolsbee also retains certain rights to the use of the words "Solar Tower" in the United States.
:I moved this remark about Intellectual property concerns from the article to here. If there are really "Intellectual property concerns" then the article doesn't not belong in Wikipedia at all, but in a bank vault :-). But I think it is BS: The ancient Babylonians had already "Solar Towers". and so did the Aztecs. JdH 06:46, 9 June 2006 (UTC)
replies: text: Discussion of intellectual property and trademarks are valid topics. They need to be brought back out in the open.  This should be brought back onto the page ... perhaps with a link so we can see some evidence for truth.--Flexme 22:45, 12 July 2006 (UTC)
thread_title:  Intellectual property concerns 

message: This article appears to be written by H. Alfred Goolsbee, User:Proton44. This would explain the promotion of http://wiki.solartower.com, which despite its amateurish appearance is listed as the first external link, and also the emphasis given to enviromission.com and SolarMission over other promoters and implementors of this idea. -- Tim Starling 05:47, Oct 15, 2004 (UTC)
:Yes, it does appear to be self-promotion. Mr. Goolsbee has also been busy finding solar and fuel-cell related articles on Wikipedia, and adding links to his project at the bottom.
:I moved the Benefits and History sections to Solar chimney, as they don't apply specifically to his Solar Tower brand. I also copied the intellectual property section, it's in both articles. I wasn't sure what to do about capitalization - in the chimney article, I'll remove most mentions of Solar Towers. In this article, I think we should use lower case "solar tower" or the term "solar chimney" when we refer to a generic solar chimney, and "Solar Tower" only when referring to the activities of the companies using that brand. Since this article is not an advertisement, we don't need to use trademark symbols - Mr. Goolsbee, please don't reinsert them. Rhobite 13:21, Oct 15, 2004 (UTC)
:Hmmm, I've removed the duplicated Intellectual property... section from solar chimney before reading the above... it seemed to refer only to this particular design, not the more general concept. They seem vague about exactly what they're claiming... the enviromission website reads in part EnviroMission owns the exclusive licence to German designed Solar Tower technology in Australia, which doesn't seem to affect other solar chimney designs, but it's an interesting turn of phrase. Why German designed? Is this qualification intended to extend the claim to all German work, or to restrict it to only German work?
:The claim in the now moved history section that no patent was granted following the building of the German prototype is another interesting turn of phrase. Was one applied for? If so, why was it denied? Andrewa 20:36, 17 Oct 2004 (UTC)
thread_title:  Self-promotion? 

message: Does anyone know how much energy the Wentworth Shire tower is expected to produce? Akamad 08:25, 23 September 2005 (UTC)
thread_title:  Production capacity 

message: Those two pages Solar Tower and Solar Tower Buronga are both about the very same structure; it like having two articles, one about Golden Gate Bridge and another one about Golden Gate Bridge (San Francisco). There is already a third article about solar chimneys in which the generic concept is discussed.
Specifically, I would suggest to move the section about Competition from Solar Tower into Solar chimney, and take the specifics about Schlaich, Bergerman and Partner, EnviroMission and SolarMission Technologies Inc. and details of construction as there is in  Solar chimney together with Solar Tower Buronga and merge that into Solar Tower.  That way Solar chimney can be cleaned up and can be devoted to the concept only, and we will have one single article devoted the proposed commercial realization and construction of one of those structures in Australia. JDH 14:40, 29 January 2006
:See Talk:Solar Tower Buronga. Andrewa 19:48, 18 February 2006 (UTC)
replies: text: see Talk:Solar_chimney#Merge_Proposal JdH 16:49, 17 May 2006 (UTC)
replies: text: I've moved relevant material here from Solar chimney (see Talk:Solar_chimney#Merge_Proposal). It will need to be tidied. --Singkong2005 (t - c - WPID) 06:13, 24 June 2006 (UTC)
thread_title:  Merge Proposal 

message: I just removed an entire section on Byproducts which I thought
 was not germane to the topic of the article. I will move it here
 for future reference JdH 18:27, 29 June 2006 (UTC)
thread_title:  Byproducts 

message: EnviroMission is planning to build a solar tower, the Solar Tower Buronga, in Wentworth Shire, New South Wales, Australia. The originally-announced design called for a 200MWatt tower at a height of 1km and costing around AU$900 million. If built, it would have become the tallest structure in the world by a significant margin, and the announcement attracted significant world attention to the Solar Tower concept.
During the final design stages, new heat absorption and storage technology was acquired which reduced the height to around 650 metres while generating the same level of power.
Shortly after taking on the services of Australia's largest investment bank Macquarie Bank (at the time famous for their infrastructure investments and risk-management) the scale was reduced again to only a 50MWatt tower. This would be the minimum size and the most risk-averse option in what the company announced as a "flexibly scalable" 50-200MWatt range that can be scaled to local and nearby demand.
No information has been released on the final size, but applying the square-cube law suggests an estimate of 450 metres or less.
In December 2005 it was announced that EnviroMission Australia and Leighton Contractors have terminated the deal they made in 2002 for the construction company to design the solar tower. EnviroMission appears to be negotiating with Baulderstone Hornibrook  to engineer the solar tower instead. The status of these negotiations remains unclear.  
Enviromission is also working with Sunshine Energy (Aust.) Pty Ltd. who have made an initial USD$8,000,000 investment to enable development of this technology in China, and a third Solar Tower is reputedly to be built in Texas although few details are available.
For comparison, the Concentrated Solar Power (CSP) Plant using the parabolic trough principle called the SEGS system,  in California in the United States, produces 330 MW, and it is currently the largest solar thermal energy system  in operation. 
Furthermore, Southern California Edison announced an agreement to purchase solar powered Stirling engines from Stirling Energy Systems over a twenty year period and in quantities (20,000 units) sufficient to generate 500 megawatts of electricity.
 Stirling Energy Systems announced another agreement with San Diego Gas & Electric to provide between 300 and 900 megawatts of electricity.
 </div>
This conversation has been moved from my talk page, and inserted here at approximately the right point in the timeline. --Scott Davis Talk 23:19, 13 July 2006 (UTC)
thread_title:  Solar Tower Buronga 

message: the betz limit is discussed in depth in the wind turbine page ... its derivation involves comparing the speed of the wind going through the turbine to the speed of the wind far away from the turbine ... this has absolutely no place here, the turbines in this tower will be enclosed and are not subject to this limit. I believe we should completely discard discussion of the betz limit.
The turbines used here are more like turbines, engineers do not apply the betz limit in here.
the only reason i have not done this yet, is that three people i have discussed this with have disagreed with me ... however the truth is not democratic.--Flexme 15:12, 10 July 2006 (UTC)
replies: text: Does "far away from the turbine" mean undisturbed air in the same plane as the turbine, as you interpret here? I interpreted it as meaning upstream and downstream in the airflow through the turbine, but in steady flow outside of the local effects of the turbine. If the Betz Limit does not apply, there must be some other study of fluid dynamics that expresses theroetical calculations on how fans, turbines, propellors etc work, and how to identify the optimal size, angle of attack, speed etc. Intuitively, if all the kinetic energy is removed, the airflow stops, and if none is removed, the turbine stops, so there must be some middle ground. --Scott Davis Talk 23:21, 12 July 2006 (UTC)
replies: text: i love your reasoning ... "if all the kinetic energy is removed, the airflow stops, and if none is removed, the turbine stops, so there must be some middle ground" you moderator you!!!! ... unfortunately it is not appropriate in a applied physical scenario ... the limit may approach either end of you bounds up to 99.99999999%   Of course there will be best efficiencies that are achieved in our current technology ... it will be related to , in particular, subsonic (possibly incompressible) air flow through a turbine in a pipe ... hopefully we will find this soon.--Flexme 09:52, 13 July 2006 (UTC)
replies: text: The discussion on Betz's limit comes from the article by Haaf et al "" It is up to you to come up with a source that repudiates Schlaich himself JdH 20:33, 3 August 2006 (UTC)
thread_title:  Betz limit 

message: it is presently claimed that winds at the top of the tower will disrupt the function. surely an atmospheric wind would cause suction at the top of the tower due to the venturi effect, this should increase the suction and give a greater productivity ... perhaps a power generator could be constructed utilising this alone ... aiming at the  prevailing strong winds--Flexme 15:28, 10 July 2006 (UTC)
replies: text: There are two references that discuss the effect of atmospheric winds, and they look at different effects and come to very different conclusions. The El-Haroun paper looks at the effect of wind speed at the top of the tower, and claims that "the mean inlet air velocity to the solar turbine is found to be 117% of its value for a wind free turbine"; those numbers were calculated for a location somewhere in Egypt. The Serag-Eldin abstract looks at an entirely different effect; it seems more concerned about wind effects on the collector. It says "The analysis reveals a total degradation of performance with strong winds, and considerable degradation even with weak winds unless the collector inlet height is relatively low". JdH 15:36, 11 July 2006 (UTC)
replies: text: sounds interesting ... do you have links that work ... i try those there but do not seem to be able to find them ... maybe it is just my computer?!   I would like to see a better discussion of these effects.  I am sure we can work something out.--Flexme 14:02, 12 July 2006 (UTC)

text: training and qualifications are surely irrelevant, most successful students are pitifully unaware of the truth, truth should see through such trivia ... the truth will be ultimate ... i will do my best to see the ultimate come A.S.A.P.--Flexme 10:45, 13 July 2006 (UTC)
thread_title:  Atmospheric winds 

message: The solar updraft tower does not convert all of the incoming solar energy into electrical energy.  
Test units of 50 kWe have been built with a solar-to-electric net annual efficiency of 0.05%.  According to model calculations an updraft power plant with an output of 200 MW would need a collector 7 kilometres in diameter (total area of about 38 km²) and a 1000 metre high chimney.  With total area of 38 km², it appears that it would extract about 0.5%.  of the solar power (1 kW/m²) that falls on the area it covers. Because no data available to test these models on a large-scale updraft tower there remains uncertainty about the reliability of these calculations.  Many designs in the solar thermal group of collectors have higher conversion rates. The low conversion rate of the Solar Tower is balanced by the low investment cost per m² of solar collection.3. Solar Energy Systems Status Report on Solar Trough Power Plants
If less than 1% of the sunlight becomes electricity, then where does 99% of the energy go?  Some of the causes of loss are shown below.
1/ Reflection of light off the top of the canopy imply a loss of 7.7% of incoming solar energy, as calculated by the fresnel equations, if the canopy is made of common glass.
2/Transmittance losses of sunlight through the canopy. this requires detailed information about the frequency components of the incoming light, and the absorption properties of the canopy.  {Analysis of regular sunlight through glasses should be available somewhere.}
3/Reflection of light off the floor of the greenhouse and back out through the canopy, taking its energy with it. This will be very highly dependent on the surface on the base of the greenhouse.
4/Heat leakage by radiation and conduction back out through the canopy from the higher temperature environment under the canopy, to the lower temperature environment above it.  These losses will be proportionally related to the surface area, and the surface area of the canopy is likely to be huge. {i am guessing that these may be reduced a little through double glazing of the central section of the canopy where heat is highest, and careful selection of material used for the canopy.}.
5/Turbine losses {i think these will only be quite small, turbines have always been quite good, computers have made them more efficient}.
6/Turbulence losses may erupt around the base of the tower where high speed is seen, especially in a faulty design.  Inside the tower, laminar flow or turbulent flow may dominate depending on the flow characterisics, narrow towers would tend to exhibit turbulent flow with greater energy losses, wide towers are likely to be laminar. {excessive width will result in a lack of chimney effect}
7/Skin friction losses will be where laminar flow dominates.
8/Imperfect tower height.  {Thermals have a height to which the convection currents rise then become stable, to go lower or higher than this height will result in energy loss.  even if the tower is made to exactly the correct height, it is not clear to me that all energy will be extracted.  the glasshouse temperature and local atmospheric conditions will affect the best height; the fact that the atmosphere constantly changes makes this a very difficult loss to avoid.  however from a realistic construction point of view it does seem clear that bigger is still better.  complete disfunction may result in the case of a temperature inversion} 
::{i have put some discussion of my ideas on optimal tower height in my talk page, it is a little too hazy, and controversial to have here as yet, feel free to look and/or contribute.}--Flexme 07:11, 15 July 2006 (UTC)
thread_title:  Conversion Rate of Solar Energy to Electrical Energy 

message: A solar updraft tower with a sloped collector on the side of a hill facing toward the equator, can be located at high latitues, such as in Canada, and may then produce up to 85% of a similar plant at low latitude locations. .--Flexme 02:43, 13 July 2006 (UTC)
thread_title:  move to Adaptations section 

message: Can the land under the outer rim still be used for farmland?
This will require water (is water infusion into the airflow a positive or a negative?).
What percentages of the land used are either too hot or too windy?--Flexme 16:52, 10 July 2006 (UTC)
replies: text: i just went hunting through the solarmission website ... they discuss degradation of concrete, a dry arid environment is required otherwise the tower is likely to degrade more rapidly.  So water seems to be bad for longevity of the power plant. They also discuss temperatures as much as 100F above ambient ... and will kill plants ... i will imediately remove any farm type comments in the page.--Flexme 03:27, 11 July 2006 (UTC)
replies: text: with the Floating Solar Chimney Technology, there is no concrete tower, and so the introduction of water may be sensible in this case.   however it would still only leave the outer rim of the glasshouse usable.--Flexme 14:01, 12 July 2006 (UTC)
thread_title:  Farmland under the canopy? 

message: The issue on edits concerning advantages and shortcomings was submitted to the Mediation Cabal, and the case is now open at Wikipedia:Mediation Cabal/Cases/2006-07-12 Solar Updraft Tower. If you have any suggestions, arguments or compromise proposals, please comment or take part in the discussion on the case page. I'd also suggest to avoid further personal discussions here and continue them on the case page so they don't affect the article and can be better addressed.  CP/M 03:47, 13 July 2006 (UTC)
thread_title:  Mediation 

message: :Conversation started at Wikipedia:Articles for deletion/Floating Solar Chimney Technology
* I already put in a single line about it. I wouldn't want to spend more characters on it, because it is one of those hairbrained schemes that wouldn't work. What the author didn't think of is that the Solar chimney is based on the fact that there is a pressure difference between outside and inside the tower; and that pressure difference gets bigger the higher the tower gets. Schlaich actually describes the use of internal bracings (spokes) to strenghten the tower. In short: The tower needs to be pretty sturdy to keep it from collapsing under the pressure difference, and it will therefore be far too heavy to keep it up with balloons. JdH 02:10, 10 July 2006 (UTC)
replies: text: *All there is is one single article, nothing else. There are no independent confirmations from other investigators. JdH 08:11, 14 July 2006 (UTC)

text: *In that case there is a positive pressure difference; in the case of the solar chimney there is a negative pressure difference. Therefore, an unsupported floppy solar chimney would deflate rather than inflate. JdH 08:11, 14 July 2006 (UTC)
replies: text: If I read JdH correctly, you claim that the pressure inside the solar tower is lower than the pressure outside it. This may be true near the bottom (the pressure in the bottom of the tower is presumably lower than the pressure under the canopy), it cannot be true at the top, or atmospheric air would pour in to the tower instead of acting as a chimney. Or is it all powered by convection, not pressure differences? Either way, I'd imagine the choice of concrete rather than lightweight fabric with hoops for the top part is based on requirements of stability or durability, not rigidity and strength. --Scott Davis Talk 02:41, 15 July 2006 (UTC)
replies: text: the issue of loft of a heavy tower could be simply solved ... there is a continual massive stream of warm air coming out the top of the tower, this can be diverted as needs arise, into a huge hot air balloon providing lift. i doubt this would be more feasible than i standard concrete tower ... as jdh says it will require support ... without a rigid framework the tower will not give suction to the turbines at the base ... of course the turbines could be at the top of the tower floated up by the giant balloon, then the tower would be inflated .... hmmm quite wild.--Flexme 05:07, 15 July 2006 (UTC)
thread_title:  floating chimney 

message: ===Reasoning===
Flexme has been arguing for a rename from Solar updraft tower to Solar tower, and I felt this is best addressed in a separate section. 
The various sides of the issue were considered recently and at least some of the changes that were made were a definite improvement (e.g. solar chimney now refers to the passive solar architectural feature, rather than the energy plant). So let's say, good work so far, but there's nothing to prevent us making further changes as well. 
Arguments for moving to "Solar tower": Flexme is correct that googling "Solar tower" mainly leads to the solar power generation structure (i.e. the subject of this article), and that's what solar tower usually refers to in the media. So Solar tower probably shouldn't lead to a different topic. Solar updraft tower might be a better name for the device, but it is also less than ideal from the point of view of the convention of using common names. (Of course we shouldn't overdo it, but in this case I would argue that the overwhelmingly more common name is "Solar tower."
Arguments against moving to "Solar tower": As I understand it, "solar tower" until very recently was used almost solely to refer to the astronomical observation tower. That's a fairly strong argument that Solar tower should not lead directly to a different topic. 
All of that leads to my suggested resolution, which I'll put in a subsection below. It may not be everybody's favorite solution, but it might be one we can all live with happily enough - or it might prompt someone to suggest a more acceptable solution. --Singkong2005 tc 01:32, 17 July 2006 (UTC)
replies: text: The problem with with Solar tower (energy plant) is that it does not resolve ambiguity. The word updraft is needed to differentiate it from the Solar power tower. Energy plant is not a good Google keyword either; see below for a discussion of that issue. JdH 19:55, 17 July 2006 (UTC)
replies: text: As updraft is not part of the common name, it's best included within the parentheses. e.g. Solar tower (updraft energy plant) or Solar tower (updraft power generation). --Singkong2005 talk 12:48, 30 July 2006 (UTC)

text: Yes, I should have done that - have put a note there now. --Singkong2005 tc 08:05, 18 July 2006 (UTC)
thread_title:  Rename (revisited) 

message: Flexme has been arguing for a rename from Solar updraft tower to Solar tower, and I felt this is best addressed in a separate section. 
The various sides of the issue were considered recently and at least some of the changes that were made were a definite improvement (e.g. solar chimney now refers to the passive solar architectural feature, rather than the energy plant). So let's say, good work so far, but there's nothing to prevent us making further changes as well. 
Arguments for moving to "Solar tower": Flexme is correct that googling "Solar tower" mainly leads to the solar power generation structure (i.e. the subject of this article), and that's what solar tower usually refers to in the media. So Solar tower probably shouldn't lead to a different topic. Solar updraft tower might be a better name for the device, but it is also less than ideal from the point of view of the convention of using common names. (Of course we shouldn't overdo it, but in this case I would argue that the overwhelmingly more common name is "Solar tower."
Arguments against moving to "Solar tower": As I understand it, "solar tower" until very recently was used almost solely to refer to the astronomical observation tower. That's a fairly strong argument that Solar tower should not lead directly to a different topic. 
All of that leads to my suggested resolution, which I'll put in a subsection below. It may not be everybody's favorite solution, but it might be one we can all live with happily enough - or it might prompt someone to suggest a more acceptable solution. --Singkong2005 tc 01:32, 17 July 2006 (UTC)
thread_title: Reasoning

message: Proposal: Have the disambiguation page at Solar tower, linking to renamed pages Solar tower (energy plant) and Solar tower (astronomy). 
::The problem with with Solar tower (energy plant) is that it does not resolve ambiguity. The word updraft is needed to differentiate it from the Solar power tower. Energy plant is not a good Google keyword either; see below for a discussion of that issue. JdH 19:55, 17 July 2006 (UTC)
replies: text: As updraft is not part of the common name, it's best included within the parentheses. e.g. Solar tower (updraft energy plant) or Solar tower (updraft power generation). --Singkong2005 talk 12:48, 30 July 2006 (UTC)
replies: text: Yes, I should have done that - have put a note there now. --Singkong2005 tc 08:05, 18 July 2006 (UTC)
thread_title: Proposal to make [[Solar tower]] a disambiguation page