Talk:Solar energy/Archive 6

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Looking for levelized cost of solar water heating

The solar water heating blurb needs an estimate of price/kWh. This only one I've found comes in at 7.25 cents/kWh.FSEC —Preceding unsigned comment added by Mrshaba (talkcontribs) 23:02, 9 June 2008 (UTC)

Found and added prices for US. China is much lower but I do not have a source. Mrshaba (talk) 18:53, 11 June 2008 (UTC)

Comments from copyedit

I've just completed a complete copyedit of the article, and have a few comments (which I've listed on the WP:LOCE copyedit request page, but thought it would be useful to include here also:

  • The myriad of subarticles on solar cells and photovoltaics, especially with regards to spacecraft and satellites, is very confused and needs to be attacked by someone with a clear plan of how the subject should be broken down and structured. In editing the article I found Photovoltaics, Photovoltaic array, Solar cell, Photovoltaic module, Space solar power, Solar power satellite, Solar panels on spacecraft and a few other relevant articles, none of which contained all the information found in the Photovoltaics section of the Solar Energy article. Some of there are obviously necessary, but I can't help but feel that some of them could be combined to give a more streamlined division of information.
  • With the costs per kWh given for solar energy, some comparison to "traditional" power source unit costs (for example for coal or other fossil fuels) might be useful for context (unless it's there already and I just missed it).
  • The scope of this article is so broad I think it probably merits its own WP:WikiProject. Many of the sections could probably be ruthlessly trimmed, but only once pages suitable for the displaced information are available. This is already true in some cases (and I tried to move some information to subarticles where this was the case).Adacore (talk) 18:23, 13 June 2008 (UTC)
Also, there's still a fair bit of duplication in the article, especially in the photovoltaics and development, deployment and economics sections. I may take another look at this and try to sort it out. Adacore (talk) 18:31, 13 June 2008 (UTC)
The scope is indeed broad but that's part of the appeal of the page. It has been difficult to condense things down and still show some relevant connections between historical and current development, other energy technologies etc. The 10% you shaved off with your ce definitely helps. I wrote the PV section with those extra details mostly because more people are interested in PV than other solar technologies on the page. That's a good idea about comparing costs so I'll make up a simple table in the DDE section with levelized costs for coal, NG, hot water, PV, and CSP. The DDE section is the most recently completed part of the page so there are doubtless some things that can be moved around. Mrshaba (talk) 01:51, 14 June 2008 (UTC)
I wonder if we need to sort out the logic of the whole series of articles before this goes to FA. I think some merger would be appropriate. Solar cell, perhaps better called photovoltaic cell could continue to carry the science of the photovoltaic effect. Photovoltaics is the main article for the technological applications. Solar module and solar array could probably be merged with it. Solar panel is dreadful at the moment and should become a disambiguation page for Photovoltaic module and Solar water heating. Building integrated photovoltaic could perhaps still have its own page. Perhaps all the space series could be merged into one. Itsmejudith (talk) 17:02, 14 June 2008 (UTC)
I have no problem with that. We need a few more copy edits cycles here anyway. I looked at the wikiproject page Adacore suggested. Would you like to start a solar energy project and set up a classification system? Mrshaba (talk) 17:16, 14 June 2008 (UTC)
There's also Photovoltaic system. I'm not sure if there will be enough people interested in participating in a wikiproject. I'm already in some wikiprojects and they run out of energy really quickly. I'd rather use the existing projects to garner more interest in these articles. I'll keep thinking about it though. Itsmejudith (talk) 17:18, 14 June 2008 (UTC)

Oh right, I was thinking photovoltaic system could cover solar module and solar array. These terms {module, cell) are getting a bit anachronistic right now due to thin-films. What are the existing projects? Mrshaba (talk) 17:26, 14 June 2008 (UTC)

The existing projects are Physics, Energy and Environment as listed at the top of this page. We could ask at Energy whether there is interest in a project on Renewable Energy. Concerning what you say about the series of articles, let's check that Photovoltaics covers everything that it should, and then that there are sub-articles only for topics that are too detailed for the Photovoltaics article itself. This article is as close as dammit to FA now. Itsmejudith (talk) 06:55, 15 June 2008 (UTC)
I've just remembered that many Wikiprojects have work groups. Perhaps the Energy project would like to have a work group on renewables and/or one on solar. Itsmejudith (talk) 07:04, 15 June 2008 (UTC)

Solar resources

While fossil fuels are derived from photosynthesis they are not considered a 'solar resource' according to Scheer. Solar resources are essentially the solar portion of 'renewable energy'. [1] Mrshaba (talk) 16:11, 14 June 2008 (UTC)

Thanks. I think we've discussed this before. And also hydroelectric. Although we all understand how solar energy powers the hydrologic cycle, it is not usual to classify hydroelectric power as solar. Itsmejudith (talk) 16:57, 14 June 2008 (UTC)
And neither are wood or biomass solar energy, in that context. 199.125.109.31 (talk) 14:41, 15 June 2008 (UTC)
True. Itsmejudith (talk) 08:38, 19 June 2008 (UTC)

Relation to the Photovoltaics sub-article

The relation between the content of the Photovoltaics section in this article and the content of the Photovoltaics article needs attention. The section in this article is structured chronologically. It closely follows Perlin 1999 with extra references mainly to US DOE; no problem with that as these are good sources. The Photovoltaics article does not carry any of that but is haphazardly structured around current issues. It is implicitly intervening in the "is it worth the money" debate, without actually presenting the two sides of that debate. Arguably it suffers from "presentism". The tables it includes are confusing. There are at least two applications in it though that need mentioning in this article: building-integrated PV and PV power stations. If we don't mention either of those then we could confuse the reader by including the Nellis power station picture currently in the lead (I'd like the picture of the Sun back there) or the rooftop PV picture. Itsmejudith (talk) 07:13, 15 June 2008 (UTC)

It would probably be good to create a History of photovoltaics subarticle of the PV article and move some of what is here to that article. We do mention power plants (stations), but only briefly. Including a PV power plant photo in the lead is an excellent introduction to the subject. PV is the fastest growing energy source in the world today. 199.125.109.31 (talk) 15:28, 15 June 2008 (UTC)
A Sun picture has the lead. The PV article needs a history section, the companies section needs to go, the tables need condensing, pictures need work etc. I'm not up to tackling the whole page but I'll give it a once over. PV power stations can be mentioned in the DDE section easily enough. "The commissioning of XXX in 200X and YYY in 200Y are characteristic of the trend toward multi-megawatt power stations in the US and Europe." I don't know where BIPV goes. Maybe in the picture of the pink house? "BIPV performs double duty by generating electricity and forming part of the building envelope on this house." Mrshaba (talk) 18:50, 15 June 2008 (UTC)
Yes, BIPV in the caption. How about "Building-integrated photovoltaics is a growing field. In this house PV modules form the roof structure."? Sun back in lead, good. This does not detract from the importance of PV at all. Itsmejudith (talk) 19:48, 15 June 2008 (UTC)
Done Mrshaba (talk) 20:16, 15 June 2008 (UTC)

BIPV doesn't really need any mention because it is just a confusing term meaning mounting solar panels on the roof or on the walls of a building. It isn't really an integral part of the building, contrary to what the term would imply. 199.125.109.31 (talk) 00:28, 16 June 2008 (UTC)

No, it can be part of the building, most often forming the roof structure, sometimes a facade. See the CIS Tower in Manchester. Pilkington Glass make transparent modules that can be used in windows or conservatories. I would say this was one of the fastest growing areas, particularly in Germany. Itsmejudith (talk) 06:44, 16 June 2008 (UTC)

Levelized energy cost

Following Adacore's suggestion I asked User:Jdpipe who wrote most of the Levelized energy cost page to put together a table of LEC values. This is the table he put together for the LEC page. I'd like to trim this down and possibly convert the numbers to cents/kWh. I'm thinking Nuclear, Coal, Natural gas, Wind, CSP (I'm assuming this is Solar thermal), PV and Solar hot water. Mrshaba (talk) 03:33, 16 June 2008 (UTC)

Levelised energy costs for different generation technologies in Australian Dollars (2006)
Technology Cost (AUD/MWh)
Nuclear 40-70
Coal 28-38
Coal: IGCC + CCS 53-98
Coal: supercritical pulverised + CCS 64-106
Open-cycle Gas Turbine 101
Hot fractured rocks 89
Gas: combined cycle 37-54
Gas: combined cycle + CCS 53-93
Small Hydro power 55
Wind power: high capacity factor 55
Solar thermal 85
Biomass 88
Photovoltaics 120
I'm very anxious about this. We must not go down the road of original research. The Levelized energy cost page cites an Australian government report The Heat is On. No problem with it as a source, but I can't find in it figures for the cost of solar compared to other generation technologies. If it's there, it needs a page number. The most we would be able to do is to cite closely what it says about PV compared to othe technologies, with the minimum of interpretation, probably attributing the report in the text. Itsmejudith (talk) 21:53, 16 June 2008 (UTC)
I've been communicating with User:Jdpipe off-line and he has strong reservations as well. In particular there's an issue with comparing the LEC of a heating technology (solar water heating) with electricity technologies. Judging from how hard it's been to find LEC values for solar water heating I have to reluctantly agree. This source has the LEC info presented more accessibly but it looks out of date. California LEC So far the LEC adventure has turned up a bunch of numbers that don't agree with each other. I think CSP is roughly in the range of 10-15 cent/kWh and PV is roughly in the range of 20-40 cent/kWh but I haven't found one current source that lists both of these numbers. Mrshaba (talk) 22:52, 16 June 2008 (UTC)
Also wind and solar is much cheaper than fossil fuel or nuclear because you can sell the renewable energy credits, which offset the hidden costs of fossil fuel and nuclear power. 199.125.109.124 (talk) 03:38, 17 June 2008 (UTC)
Yes, in all the economic discussion there is the background issue of cost to whom. The owners of a large factory face a very different set of choices from the domestic consumer. Then there's insolation, distance from grid, subsidy policies... —Preceding unsigned comment added by Itsmejudith (talkcontribs) 20:10, 17 June 2008 (UTC)

Do you know how much the electricity costs from your system? Just curious. Mrshaba (talk) 20:25, 17 June 2008 (UTC)

Haven't worked it out in that way. We paid a lot for the modules and fixing system (integrated in the house roof) about ten years ago. We were too early for the government subsidy scheme. It's grid connected, 2.6 kWp. We pay just over 10p (one tenth of a pound sterling) per kWh for grid electricity and we get back just a fixed payment of £30 per annum from EDF Energy for what we export. No net metering in the UK and they can't be bothered to measure exactly how much we export. On the plus side we do have a nifty way of using the heat that would otherwise collect behind the modules and reduce their efficiency. Itsmejudith (talk) 20:45, 17 June 2008 (UTC)

1860s

The development, deployment and economics section is organised mainly on chronological lines following the Perlin source, but there is a disjunction between the chronology of electrical generation and that of solar more generally. Thus there is a reference to the early development "in the 1860s" that I don't think is to be found anywhere else in the article. The section on solar thermal starts with description of the present-day technologies. When did solar water heating actually start? Itsmejudith (talk) 21:41, 16 June 2008 (UTC)

Mouchout first started experimenting with solar troughs in the 1860s. It's mentioned in the Concentrating solar power section: "In 1866, Auguste Mouchout used a parabolic trough to produce steam for the first solar steam engine, and subsequent developments led to the use of concentrating solar-powered devices for irrigation, refrigeration and locomotion." Solar water heating surely predates this but the first "commercial" product sales started in the 1890s. Mrshaba (talk) 22:58, 16 June 2008 (UTC)

According to Perlin, regular bathing disappeared during the Middle Ages and didn't become common in Europe and America until the 1800s. Mrshaba (talk) 23:12, 16 June 2008 (UTC)
Perlin's fine for history of technology, not necessarily for social history. People may not have bathed in the intervening years but they probably did wash. They just didn't write about it much. Itsmejudith (talk) 20:47, 17 June 2008 (UTC)

Available Solar Energy vs. Worldwide Energy Demand

[[:Image:Solar land area.png|thumb|right|Annual average insolation at Earth's surface. The black dots represent the land area required to replace the total world energy supply with electricity from solar cells.]]

Recently, images have been removed from this article that visualize the available solar energy by comparing it with the world's total energy demand. I have designed a map of locally available solar energy (see picture to the right) that shows, for comparison, the amount of land needed to satisfy the current total primary energy demand. This map has been widely used as a reference in scientific publications, in different language versions of this article, and in this article itself until recently. It would be nice to reintroduce it to give readers a quick idea of the magnitude of worldwide available solar energy. Mlino76 (talk) 23:36, 17 June 2008 (UTC)

It's original research Matthias. Mrshaba (talk) 23:49, 17 June 2008 (UTC)
No, it's only original research if you do it. Everything is original research by someone. Anything that is published as a reliable source is fair game. 199.125.109.134 (talk) 01:39, 18 June 2008 (UTC)
Mlino76 designed the map and uploaded the image. That seems like OR. Mrshaba (talk) 02:08, 18 June 2008 (UTC)
There are two issues. One as stated it appears in scientific publications and two if you look at the image you will see that it is based on data that is readily available. Even you have created similar charts I believe. What would constitute OR would be if you made up the data and it didn't appear anywhere other than in WP. 199.125.109.134 (talk) 04:13, 18 June 2008 (UTC)

In which scientific publications has it appeared? Itsmejudith (talk) 09:37, 18 June 2008 (UTC)

I would suggest e-mailing the author if you are curious, but it's moot as far as Wikipedia is concerned. WP:NOR#Original images states that it is fine for you to create images as long as they are relevant to a topic and that they do not distort facts (like putting extra particles into a Hydrogen nucleus). The fact that this image has two reasons for being permissible instead of one is not important. 199.125.109.80 (talk) 20:43, 18 June 2008 (UTC)

Here are three examples where the map was published:
- Spektrum Spezial 1/07 (German edition of Scientific American), Spektrum Verlag, 2007
- New Scientist, Reed Business Information Ltd., 8 Dec 2007
- In a presentation by Prof. Michael Graetzel (see Dye-sensitized solar cells) here at UC Berkeley, 29 Feb 2008
Mlino76 (talk) 21:36, 18 June 2008 (UTC)

If it's been in the New Scientist and the German edition of Scientific American then it definitely isn't original research. If it is used here then it should be sourced to both of those. A presentation is probably not worth referencing. Who holds the copyright? Itsmejudith (talk) 08:37, 19 June 2008 (UTC)
According to the license, Mlino76 ("I, the copyright holder of this work, hereby publish it..."). No one has disputed that point. Noting other places it has appeared is totally irrelevant, and frankly gratuitous. 199.125.109.87 (talk) 22:13, 19 June 2008 (UTC)
I'll check on the reliable sources noticeboard what the appropriate citation ought to be. Itsmejudith (talk) 09:54, 27 June 2008 (UTC)

SNEC 3rd (2009) International Photovoltaic Power Generation Expo

Shanghai New Energy Industry Association decides to hold SNEC 3rd (2009) International Photovoltaic Power Generation Expo ceremoniously in Shanghai New International Expo Center (SNIEC) from May 6th to 8th, 2009

Contact Us: Shanghai New Energy Industry Association (SNEIA) Shanghai Follow Me International Exhibition Co., Ltd.

Add: Room 1008, No.1525, West Zhongshan Rd., 200235, Shanghai, China. Contact Person: James Tel: +86-21-64281523 Mobile Phone: +86-13651766051 E-mail:jiangshunchu168@163.com,james1689695@gmail.com Fax: +86-21-64642653 MSN:james1689695@live.cn QQ:343889135 Website: www.snec.org.cn ,www.sneia.org —Preceding unsigned comment added by 116.232.245.232 (talk) 08:16, 24 June 2008 (UTC)

Added a link to this and other major PV trade shows to the Photovoltaics article. 199.125.109.31 (talk) 15:56, 24 June 2008 (UTC)

Lead image

The lead image of the article should be about the article. A second image has been systematically and insidiously removed which shows the potential of solar energy. In my opinion, there is room for two images and they should be, first, an image that shows an application of solar energy, and second, an image that shows the potential for solar energy. Images of the sun are not necessary. They belong in the sun article. [2] 199.125.109.27 (talk) 06:16, 26 June 2008 (UTC)

We've discussed the box diagram extensively: Rfc Pictures, Images, Picture change, Image selection. Others have had issues with the box graphic here. There has been a consensus that the box picture is undesirable. Many people have found the graphic confusing and it uses different numbers than the text to boot. Johnfos suggested a Sun picture. Itsmejudith and I support a Sun picture. NREL, ASES, ISES and every other solar organization out there uses a Sun icon. There is a strong association between Solar energy and the Sun. I find your denial of this to be strange and given the history here I don't think you're acting in good faith. I think your objective is disruption because that's mostly what you do here. Mrshaba (talk) 18:32, 26 June 2008 (UTC)
Wrong. You clearly have a strong bias. This is the solar energy article, not the sun article. Your issues with the box diagram have been addressed and are not a factor. You will need to come to a consensus on this and quit resorting to edit warring. Quit removing useful content solely because of your bias, and possible COI. 199.125.109.27 (talk) 01:19, 27 June 2008 (UTC)
I am pleased to see that you have agreed to mediation, and I would ask that in the meantime, I won't delete your lead image if you won't delete mine. Hopefully the mediation will turn up a reasonable solution for everyone. 199.125.109.27 (talk) 01:35, 27 June 2008 (UTC)
If I might provide another opinion, I think the sun image is relevant to the Article and should remain the first image. Having said that there is a large space (or was) beside the TOC that would accomodate several images. The present number however is too cluttered, and at least one image needs to go, I would suggest the 'yellow box' as it is almost indecipherable. On the subject of images I would like to see one image for each main section, several are missing. The Article is otherwise going well and I will make some more observations soon. Jagra (talk) 06:01, 27 June 2008 (UTC)
How are you counting main sections? I only count four main sections not counting see also, etc. I think the best place for the yellow box image is beside the "Energy from the sun" section, just below the "About half the incoming solar energy is absorbed" image and in place of the dots image which should be in the lead under the Nellis image. However, there is an ongoing request for mediation regarding the lead image and until that is resolved it would probably be best to either make no changes to the lead image or move all of them to elsewhere in the article and have no lead image. The box image works better at slightly larger size - depending on what your preferences for thumb size it could be unreadable. I can read it fine at 180px, but it would be much better if it was at about 260px. The sun image is the wrong aspect ratio. It is a cropped image from one with a much better aspect ratio (it needs to be wider than it is tall). It should have been cropped the other direction, to cut off some of the bottom, not cutting off the right side of the earth as was done. Apteva (talk) 05:51, 28 June 2008 (UTC)
Well I would say most seperate headings need an image. I agree should not change until mediation is completed. The 'sun' picture is really 'sun on earth' image, not sure if any cropping changes can be made now, or can they? Jagra (talk) 06:58, 28 June 2008 (UTC)

First illustration showing power paths

I think there is a serious problem with the first illustration. It shows 111PW of power leaving the atmosphere, in the form of electromagnetic radiation. Unless the power results from stimulated emission (probably most is not), radiated power is omnidirectional, 2pi steradians heading for space, 2pi steradians heading back to Earth. This pathway is not shown. And of course I understand that the power heading back to the surface may be reabsorbed on the way, leading to another branch in the pathway, etc. ( I have a pretty good understanding of multilayer optical thin films [having written analysis and optimization programs, and designed thin film filters], wherein a somewhat related process occurs.) BTW, a portion of the reflected components has a chance of being absorbed and re-radiated, out to space or back to Earth. blackcloak (talk) 04:20, 27 July 2008 (UTC)

It's a simplified diagram for a simplified discussion. The diagram is based on a NASA image. Mrshaba (talk) 00:59, 28 July 2008 (UTC)
The power radiated back to space essentially results from blackbody radiation corresponding to the (average) temperature of the Earth. As Mrshaba says, the diagram is simplified -- what the atmosphere radiates back to Earth is either re-radiated or serves to increase the Earth's temperature (which also increases the amount of energy radiated by the Earth). For purposes of this diagram, the Earth is regarded almost (but not quite) as a point in space rather than the more complex body that it is. The Earth's atmosphere cannot be accurately regarded as a thin film -- an enormous amount of scatter occurs in the atmosphere, for one thing (that's why the sky is blue) -- so I would be careful about generalizing thin film optics to the Earth's atmosphere. However, if I'm not mistaken the results of optical ray tracing have contributed to the various pieces of information that are assembled in this illustration; I'm sure you will appreciate how this approach overcomes many of the limitations of thin-film theory when you're not actually talking about thin films.--Squirmymcphee (talk) 20:22, 29 July 2008 (UTC)
Common to thin film analysis and the optical behavior of an atmosphere are: absorption, reflection, transmission, wavelength dependencies. Less commonly, thin film analysis includes surface roughness, temperature dependencies, bulk scattering, gradient index media. Never included, as far as I know, is re-radiated (thermal) power based on temperature- although, come to think of it, the military and infrared astronomers have probably done some work in this area, if for no other reason than to determine if a large noise component can be generated that would be added to the real signal (stronly detector dependent). But this is all off the topic. I suggest that the diagram here- http://www.pep.uni-bremen.de/services/lectures/winter_2007/Richter/al-hazaimay_pres_tech_07_blackbody.ppt (go to slide 12)is a far better depiction of what should be communicated with an illustration for this article. blackcloak (talk) 05:38, 30 July 2008 (UTC)
I forgot to mention two more things. Polarization plays an important part in both cases. While polarization is always taken into account when analyzing thin films, I have not seen any treatment of the electromagnetic power pathways that takes polarization into full account. As for the second item, the referenced slide at uni-bremen.de shows how important the long wave radiation component is; the power reaching the surface from the atmosphere (the source) exceeds the power reaching the surface directly from the sun. This effect, "stored energy" or peak power exceeding the power of the driving source, occurs in (certain complicated) thin films. blackcloak (talk) 20:44, 30 July 2008 (UTC)
I was going to make a joke about you forgetting polarization but something tells me you wouldn't have found it funny. I don't see a problem with redoing the picture with a greenhouse loop. Would this address your concern? Mrshaba (talk) 23:38, 30 July 2008 (UTC)
I'd like to think it depends on how funny the joke. I can laugh at my, err, emissions. But I don't feel the need to insist you reveal your little gem. As for your question, the answer is yes. You reminded me of a long discussion I had years ago with a non-technical person about evolution, as in the "order" in a human body, and the second law of thermodynamics, which he understood to mean that everything (organization of atoms) gets more random with time. He had gotten his, ahem, knowledge from a high school text, never questioning the accuracy or completeness of what he had learned. And no one had (or could) straightened him out on the subject. I tried, but it was pretty much a losing battle. My point is: making explanations oversimplified may get a simplified view of the physical process communicated, but it can lead to long-lasting misunderstanding. People have a way of constructing wild theories, and analogizing to a social context, based on, at best, insufficiently complete knowledge. Somehow what is read from a source deemed reliable overrides what a knowledgeable person communicates verbally. blackcloak (talk) 07:15, 31 July 2008 (UTC)

Point well taken. I'll work on putting something together. Mrshaba (talk) 14:52, 31 July 2008 (UTC)

alt. img. for WP:LEDE; alt renew energy template

  • Y'all seem to have turned edit warring over images into a family pastime. So since my edit will probably be reverted soon, a link to the diff is here.
  • I moved the image up from the "Concentrating Solar Power" section, which had 2 images already (too many for a smallish section). The image has the advantage of being BOTH attractive AND being specifically about the topic of the article. I made a new template, {{Renewable energy sources 2}}. Well actually it's just the old template turned sideways. There's an alternate version (temporarily!) which has the grey band atop only the text.. but in order to fit the the wind turbine icon into the template I had to make it look kinda fat, like a pregnant water buffalo.
  • So revert away, Merry Christmas, Happy New Year, etc. Have fun, but drive safely, OK?
  • Ling.Nut (WP:3IAR) 10:37, 31 July 2008 (UTC)
  • OH PS, the CSP section only describes one technology. That looks incomplete to me. here's the caption of the photo, which should go somewhere in the text of the CSP section: "Dish engine systems eliminate the need to transfer heat to a boiler by placing a Stirling engine at the focal point.". Ling.Nut (WP:3IAR) 11:23, 31 July 2008 (UTC)
The CSP section is important to the subject but has been moved/removed by Mac and nopetro who I suspect are socks of each other. I added the text back just now. Thanks much for making the sideways template. Mrshaba (talk) 15:10, 31 July 2008 (UTC)
I hope you like the choice of images in the WP:LEDE—if it's acceptable there, then perhaps it shouldn't appear twice in the article. It's also in the CSP section. Ling.Nut (WP:3IAR) 15:13, 31 July 2008 (UTC)
I uploaded the image. I think it's a great picture but I'd like to see a picture of the Sun in the lead. What do you think? Mrshaba (talk) 15:29, 31 July 2008 (UTC)
I think an image of some sort of solar technology adheres much more closely to the point of the article. Image:Dish Stirling Systems of SBP in Spain.JPG fulfills that need, plus it's also aesthetically pleasing. Ling.Nut (WP:3IAR) 15:34, 31 July 2008 (UTC)
I disagree but fair enough. Mrshaba (talk) 15:45, 31 July 2008 (UTC)

Here's an image I think gets the point across. What do you think? Mrshaba (talk) 16:23, 31 July 2008 (UTC)

A touch romantic perhaps? There's also a copyright on it which would have to be addressed with a free license.
I do not have any strong position on the case for an image of the sun, the case for an image of some technology, or the case for representing multiple technologies rather than one. Ling's image is fine by me. Many other images would also be fine. While the lead should summarize the article, the lead image does not have to do so. This is such a minor issue, that I favour dropping it. Geometry guy 20:34, 31 July 2008 (UTC)
Maybe Mr. Orman's picture isn't a good choice. I'm just asking for input. Here are some other photos [3] that I like a lot. What do you think of the one labeled Photovoltaikanlage bei Hemau (the triangle shaped one)? I asked Mr. Leidorf for permission to use this picture and he agreed. I'm leaving it up to him to upload and I set up a place holder picture here to simplify things. I do have a question about photos though. Can someone tell me what the most protective license would be? Mrshaba (talk) 21:49, 31 July 2008 (UTC)

Waste stabilization ponds

In which section of the Article should this material PMID 18653962 be placed ? and these ones on soil remediation PMID 18656308 PMID 18161562 These ones PMID 16484076 PMID 18667225 PMID 16949121 PMID 14766599 on water purification Perhaps a new section on Industrial water and waste treatment is needed Jagra (talk) 09:40, 7 August 2008 (UTC)

The Solar energy article is very large; we have separate articles for many applications of solar energy. See the links in {{Solar energy}} and Category:Solar energy. For example: Solar water disinfection and Soil solarization. --Teratornis (talk) 16:45, 7 August 2008 (UTC)
I concur, the sections need to be consolidated into subarticles - and the information added there. Apteva (talk) 19:02, 7 August 2008 (UTC)
Well I have added solar soil decontamination to Soil solarisation, which really was about soil disinfection. Also Solar water disinfection is about SODIS only and not suitable to add the Solar water treatment items in PMID 18653962 PMID 16484076 PMID 18667225 so back to square one a new section or Article?Jagra (talk) 08:47, 8 August 2008 (UTC)

Solar chemical

Appears to be in need of an update particularily in regard to hydrogen production and this method PMID 18656909 Note the efficiencies claimed Jagra (talk) 08:37, 7 August 2008 (UTC)

Navbox/Solar energy

I have added a navbox to the Article constructed along the lines of the Article framework. Using links from the article with others added. It is a useful referencing system, probably more use on the sub-article pages to link them all together in a quasi project. I agree that a seperate Wiki project is not justified here but this can serve just as well, given many Wiki projects are effectively 'dead' anyway. There seem to be a large number of articles where mergers have been proposed, this may serve to highlight that need, rather one needs to take a NPOV position when including articles in the list. It can also serve to highlight gaps where further articles are needed (just add a proposed name) it will be coloured red until completed.

There is away of connecting a reader to the Navbox directly from the See also section, which being at the end of the text, can be seen more readily than the navbox at the end of a long Reference section, which can easily escape a readers attention. If you would like this feature i will install it also. Jagra (talk) 07:16, 28 June 2008 (UTC)

I moved the template to {{Solar energy}} to be consistent with Wikipedia's naming scheme for navigation templates based on {{Navbox}} (thousands of examples are here: Special:Whatlinkshere/Template:Navbox). I.e., no other navigation template was named as a subpage of the {{Navbox}} template. See also User:Teratornis/Energy#Template:Solar energy for my notes. I updated the links to the template, and I added a documentation subpage to it per WP:DOC. --Teratornis (talk) 17:27, 10 August 2008 (UTC)

The FA-Team would like to help this article and Scattered disc reach FA status: the mission page is linked above. Help with both articles would be much appreciated. Geometry guy 16:19, 26 July 2008 (UTC)

Copyediting comments

Hi, I'm a visitor from the FA-Team. Here are some comments that might or might not help get you over the FA hump.

  • Some reviewers at FAC might reject the first sentence, on the grounds that energy is not a process, energy is energy. Perhaps try this: "The term solar energy usually applies to radiant energy from the sun that is converted to some other form of useful energy, such as heat for a home or a steam turbine or electricity from solar cells. " - Dan Dank55 (talk)(mistakes)
I'd like to start out with an introduction of the term as a resource. Something like, solar energy is heat and light from the sun. Solar resources power the weather and climate and fuel life on earth... The second paragraph would then present SE as a technology for using the resource. Mrshaba (talk) 20:39, 28 July 2008 (UTC)
  • Personally, I'd delete the second sentence, for a bunch of reasons:
    • After a Google search, I don't buy that the terms solar energy and solar power are popularly used to mean different things. People are more likely to say that "solar energy" can mean unconverted energy, but then every example they give involves some kind of technology.
      • Let me rephrase (based on comments below): I don't buy that "solar energy" popularly means "energy from the sun", but that's the way you use the phrase in the section Energy from the Sun. - Dan Dank55 (talk)(mistakes) 20:41, 28 July 2008 (UTC)
Have you looked at the definitions here? Mrshaba (talk) 20:55, 28 July 2008 (UTC)
    • Thermoelectric converters are a marginal solar energy technology.
    • Unless you've got electric eels in the solar pond, the solar pond isn't going to convert "sunlight into electricity", except through the intermediary of heat. - Dan Dank55 (talk)(mistakes)
  • Consider something like this: "In science, power is a measure of how much energy is delivered per time interval, but popularly, solar power generally means the same thing as solar energy."
    • Per your comments below, feel free to tweak this to say that solar power is more likely to apply to electricial generation, or commercial production of electricity if you like. - Dan Dank55 (talk)(mistakes) 20:44, 28 July 2008 (UTC)
  • "Solar energy is the fastest growing form of energy production" should be one of the first things you say, followed by a short list of the most common uses of solar energy. - Dan Dank55 (talk)(mistakes) 18:15, 28 July 2008 (UTC)
  • Both your first sentence ("utilization") and my rewrite imply that, in the usual sense of "solar energy", humans or technology are involved in the energy conversion. I agree with you; that's my sense of how the term is most often used. In your Energy from the Sun section, you use the term several times, but never in the sense that you just defined it; you're using it to mean, well, energy from the sun. Perhaps "energy" or "energy from the sun" would be better in this section. - Dan Dank55 (talk)(mistakes)
  • "the rest is absorbed by the atmosphere, oceans and land masses": some of it is absorbed by me, and I'm none of the above. - Dan Dank55 (talk)(mistakes)
You're right but this is insignificant Dan... Way beyond the scope... This isn't a mathematical proof. Mrshaba (talk) 20:44, 28 July 2008 (UTC)
  • "keeps the surface at an average temperature of 14 °C": Not in my neighborhood. You'll have to define what you mean by "average" here. - Dan Dank55 (talk)(mistakes)
Worldwide mean temperature if you wish. Mrshaba (talk) 20:44, 28 July 2008 (UTC)
  • "flow of renewable energy": It's not clear what you mean by "flow" here. Also, I'm guessing the other 0.1% is geothermal energy? It would be better not to have to guess. - Dan Dank55 (talk)(mistakes)
Solar resources make up about 99.97% of the Earth's Energy Budget. The remainder is tidal, geothermal, and starshine but they are insignificant. That's why they aren't mentioned. Mrshaba (talk) 20:35, 28 July 2008 (UTC)
Whack it if you like. Mrshaba (talk) 20:35, 28 July 2008 (UTC)
  • There are judgment calls to be made throughout the article on whether to write out and whether to convert units. - Dan Dank55 (talk)(mistakes)
There is limited guidance and nobody has offered and advice. I understand the topic well enough to know there are many options: quads, BOE, TWh etc. Since it isn't a requirement, there is no obvious choice, and conversions are rather ugly I've chosen to do without. Mrshaba (talk) 20:35, 28 July 2008 (UTC)
I agree that thermoelectrics, chimneys and ponds are marginal. There's been a futile effort to mention everything in the intro but this approach should probably be reconsidered. There's really nothing wrong with something short and sweet. To Hades with the MoS. Bah humbug... I'd delete the second sentence too and move it down to the solar power section because it would have context there.
What does fastest growing mean? By rate or absolute magnitude? I don't think either measure is true for any solar technologies. Solar heating is adding 20 GW or so a year compared to 3 GW for PV and 100+ GW for coal. If a rate based comparison is used then tidal power would get the crown over solar because tidal is growing from a small base. Personally, I'd avoid setting up a fastest growing comparison.
I've argued that the intro should show "solar energy" to be both a resource and a technology for using this resource. The resources are divided between direct resources like heat and light (electromagnetic radiation if you like) and indirect resources like wind, biomass, hydro, waves, etc. Solar energy technologies are generally confined to those that involve the control of direct solar resources - i.e. technologies that utilize indirect resources are separate - a wind turbine is a wind technology, a dam a hydro technology, etc.
Also, not all solar technologies involve conversion - daylighting technologies don't convert anything and these technologies are a significant slice of the solar pie. Rather than convert I've used the word "control" but people in high places have problems with that word too. What to do eh? I called the FA team over because I'm stuck.Mrshaba (talk) 19:47, 28 July 2008 (UTC)
"Personally, I'd avoid setting up a fastest growing comparison": That's in the lead already. It sounds like you want to change it. - Dan Dank55 (talk)(mistakes) 20:17, 28 July 2008 (UTC)
Yes. It's not a true statement. Mrshaba (talk) 20:44, 28 July 2008 (UTC)
Do the google search again. I've looked into it in depth and written most of the solar energy organizations in the US in the process. I see "solar power" associated with generation more so than the term "solar energy". It's more of a general observation and it is by no means absolute but there are a few sources, (Harold Hay, Scott Sklar) that have explicitly made this point. Scott Sklar answered my question here. The fellow from NREL agreed that Solar Power goes with generation while Solar Energy is more generic all encompassing term. Frank De Winter, another hall-of-famer, agreed with Sklar but he pointed out that the US doesn't have a Academie de Francais to work out how the language should develop. You've got the science thing right and I see your point. This isn't about the scientific difference between energy and power but the popular understanding of the terms solar energy vs. solar power. There isn't an absolute answer here. The current phrasing is a pretty good compromise. Mrshaba (talk) 20:07, 28 July 2008 (UTC)
That's not my first sentence. I think the term should be introduced as a resource first. Mrshaba (talk) 20:13, 28 July 2008 (UTC)
  • I'm seeing some things that were brought up at the recent FAC: citations needed, conversions needed, words that readers can guess at but would be better with some explanation (concentrating, hybrid). Of course, it's not necessary to head back to FAC, but if you want to go in that direction, I'd suggest tackling these things. - Dan Dank55 (talk)(mistakes) 20:38, 28 July 2008 (UTC)
Again, conversions are not required. There's no clear choice so no choice should be made besides metric. That's my feeling. I've looked into the citation needed tags but haven't had much luck. Of all the tags I'd say the solar chimney one is valid but most of the remaining citations have confounded me. I can't find references for obvious statements like, some solar technologies produce energy (PV, SHW, CSP) while others reduce the need to consume energy (shading, reflective coatings). I've removed the pumped-hydro blurb from the page a few times because it doesn't have a connection to SE but it keeps coming back. Ummm... Do I remove it again or add a citation to a generic storage technology that I don't think is relevant to the subject? Most of the remaining tags go with hobby-technologies that ISES doesn't write about. I can't find a "respectable" source for how a solar balloon works. The FAC helped remove some junk sources but it did not give me any feedback on what a good-enough source looked like. I asked... You'd think Wolfgang Scheffler's site would be a good enough source for Scheffler reflectors but I didn't get a reply. That kinda pissed me off. The FAC kinda pissed me off in general.
The world's slowest mediation process with Apteva has been taking up the rest of my time. I was hoping the mediation process would clear some things up but it's made matters worse. I can't even get the mediator to follow the established consensus. Wow... How hard should that be? Meanwhile the page is getting hassled by a sockpuppet user with poor english skills that keeps moving high quality content and leaving a mess behind. Dammit. I appreciate your help Dan but you guys have come at a bad time as far as my energy level goes. And I mean this in the best way but I can't handle anymore arguing over the difference between solar energy and solar power. Mrshaba (talk) 21:47, 28 July 2008 (UTC)
Metric is fine. I only just discovered the mediation stuff and have commented there. I have not minced my words: what a colossal waste of editor time that has been. Mine included: I spent much of Saturday preparing a critique of this article for advocacy, when one of the main issues which stimulated my concerns was the presence of two POV images. I intend to remove these images from the article. They are a clear barrier towards improving the article to FA standards. Geometry guy 21:34, 30 July 2008 (UTC)
Thank you Geo. I've been trying to remove the box picture for about a year. I initiated an RFC that showed a clear consensus to remove it but it came back. I had it removed for lacking a source but but it came back. We removed it as part of the mediation procedure but it came back. I'd like to see it finally go but Apteva, Oakwillow, 199.xxx, and whoever else he is has managed to keep it on the page against my best efforts. I also have problems with the dot image for some of the reasons you cited. The only other example of advocacy that I can recognize is this blurb:

"Since 2006 it has been economical for investors to install photovoltaics for free in return for a long term power purchase agreement. 50% of commercial systems were installed in this manner in 2007 and it is expected that 90% will by 2009.[106] Nellis Air Force Base is receiving photoelectric power for about 2.2 ¢/kWh and grid power for 9 ¢/kWh.[107][108]"

Squirmy could quote an accurate price range but it's about 20-40 cents/kWh. This is a far cry from 2.2 cents/kWh so something is clearly amiss. You guys might be wondering why I don't remove this stuff myself. I have... repeatedly... but they come back... See the pattern yet? If you see any other examples of advocacy besides these please bring them up because I'm probably responsible for them. Mrshaba (talk) 23:25, 30 July 2008 (UTC)

Would some brave soul check whether the serial comma is used more often that not, or vice versa? I'm unsure. Nousernamesleft (talk) 20:36, 10 August 2008 (UTC)

I don't generally use serial commas but patient copyeditors have inserted them where I left them out. Serial commas should be considered the convention on the page. Mrshaba (talk) 20:56, 10 August 2008 (UTC)

power per unit area

woud be nice to know the power delivered by sunlight to , say, a square meter of ground. thx — Preceding unsigned comment added by 68.240.189.9 (talk) 03:39, 29 July 2008 (UTC)

Ouch, someone actually trying to use this article. The average insolation image with the little black dots shows that if you are in the blue area the average is 100 to 150 W/m^2 (this is an average over several years), green, 150 to 200, yellow, 200 to 250 and gold 250 to 300. For most of the worlds populations it ranges from 150 to 300, but that is a two to one variation depending on where you live. It doesn't affect whether you can use solar energy, just how much bigger (or smaller) the collectors need to be for the same amount of energy. 199.125.109.124 (talk) 00:00, 12 August 2008 (UTC)

History

For an Article where I keep hearing 'too large' as a catchcry for not including recent developments, there is an awfull lot of past history, that I think is largely redundant in this Article.

A quick read indicated to me about 35 to 40 lines (several sections worth) not including Photovoltaics that should probably be retitled History of photovoltaics or Experimental solar power that also is another past history lesson, that can be severly pruned.

History would be better dealt with in the linked Main Articles where seperate sections can be devoted to it. Solar energy is really about the future and new technologies. A better balance needs to be attempted here, if we are serious about size reduction. Any comments first. Jagra (talk) 08:10, 9 August 2008 (UTC)

For general guidelines on article length and how and when to split sections into separate articles, see EIW:Long. Note that this is typically an ongoing process. Someone may initially add content to a large article, which someone else later refactors into related articles. Thus it is not highly critical where the content goes first; someone can rearrange it later. As the field of solar energy is rapidly developing and expanding, the Solar energy article may have a tendency to get too long, since more people would look to the main article first before checking to see that we have articles on subtopics. As to writing a History of solar energy article, precedent exists in the form of Wind power and History of wind power. But before starting a new article, search Wikipedia (for example with {{Google wikipedia}}) to make sure there isn't already an article about the history of solar energy under another name. --Teratornis (talk) 16:54, 9 August 2008 (UTC)
The length of the article does not concern me in any way as this page is of similar length to its peers (nuclear, wind, hydro, coal) and it's well within the article size guidelines. I've removed that "to do" several times but it has returned just as the box picture has. I do not agree with the statement that this page should be about the future of new technologies. I don't know how it could do that. Passive design, concentrating solar thermal, and solar water heating are all rather old technologies. These technologies certainly represent the present and you can make a strong argument that they will represent the future of solar energy more the latest dye-sensetized nanotube solar cell ever will. If you look through other encyclopedias and overviews of the subject you'll find plenty of history. The Coming Age of Solar Energy by Halacy, Direct use of the Sun's Energy by Daniels and A Golden Thread by Perlin are all classic books on the topic that are heavy on history. The past is prelude. Do as you wish though. Mrshaba (talk) 17:05, 9 August 2008 (UTC)
The history of solar energy is a large and important topic in its own right which might deserve a separate article. However, someone would have to do the work to create it. It's just an idea to consider. Solar energy is currently 71 kilobytes long, and thus Wikipedia:Article size#A rule of thumb suggests the article may have some scope for subdivision. Of course Wikipedia has lots of long articles, notably on several other energy-related topics. The mention of article size is more to encourage users with new content relating to solar energy to look first to the specialized solar energy articles rather than adding everything to the main Solar energy article. If someone wants to apply the summary style makeover to Solar energy, that might usefully shrink the article so it can accommodate future natural growth. Many articles on Wikipedia have a natural tendency to grow over time. Note that creating a History of solar energy article would not obliterate all historical content from the Solar energy article, merely shrink it to a higher-level summary with a link to the detailed article. But as creating new articles like this requires a fair amount of work, it all depends on someone who feels personally motivated enough to make it happen. And of course it requires consensus. --Teratornis (talk) 17:31, 9 August 2008 (UTC)
Also, on Wikipedia we should try to follow policies and guidelines rather than taking other articles as precendent. See: Wikipedia:There is no common sense and Wikipedia:Other stuff exists. Other energy-related articles have gone through split-ups (e.g. Peak oil and Wind power) - while still remaining long, and continuing to grow. Splitting articles on these dynamic topics does not result in the articles becoming small, it's more a way to keep them from growing to extreme size. --Teratornis (talk) 17:38, 9 August 2008 (UTC)
The Article size guidelines refer to readable prose. This page comes in at 36 kilobytes. Mrshaba (talk) 17:41, 9 August 2008 (UTC)
Those guidelines are total BS. The numbers are mislabeled as readable character counts when they were actually developed to mean edit byte count, the number that gets displayed just above the edit window ("This page is 71 kilobytes long.") and also displayed in the article history, "(73,529 bytes)". This needs to be corrected but several editors have tried and failed, due to watchdogging by editors of long articles who apparently want to pretend that their articles aren't really that long. This article has multiple sub-articles that can already be utilized to greatly reduce the size of the article. Just look for the word "main", and delete all but a summary paragraph of that section. I would recommend a History of photovoltaics first (and link it from the photovoltaics article and not here), rather than a history of solar energy, which would have to go back many thousand years. While "main" appears 16 times, five of those are in sub-sections of the solar thermal sub-section and can be simply deleted, and the one sentence summary expanded. The main section "applications" should not be a named section, as it includes most of the article. Apteva (talk) 19:36, 9 August 2008 (UTC)

(indent reduce) The Article appears to be twice as long as desirable, I hear the argument about readable prose but the loadability of the Article (discussed here) on other platforms surely means total length of 32 kB? In which case there is enough material here for two Articles. Thats why I like the suggestion for the 'History of solar energy'. Solar energy can only grow over time and room to grow is already needed. Yes it does take time to write another article but by hiving off slabs from here it will have a good start others can build on, rather than just junk the material and the work put into it. Also it provides a recoverable source for the Article if need be. I would suggest first removing material to a sandbox set up for it and see how it then looks.

I agree the overall structure does need a review, I prefer in a summary article such as this for each section to summarize Main articles. Jagra (talk) 08:11, 10 August 2008 (UTC)

Trying it out in a sandbox is not really necessary - just use "Show preview" to "see how it then looks". You can't accidentally lose anything - Wikipedia saves every version of every article - click on the "History" tab and you can see all 5,000+ versions of this article. Click on the date/time links to see each version. Apteva (talk) 05:45, 11 August 2008 (UTC)
The article size policy is clear about readable prose and this page is within the guidelines at 36 kB i.e. Splitting is not suggested based on size alone. The technical issue you speak of are a legacy problem and they do not overset the readable prose guidelines. The 100+ kB of pictures have more to do with the actual page size than anything else. Your suggestion to set up a sandbox and try something is a fine one but I don't think you'll have enough to work with.
The structure is mostly based on notability but it loosely follows the basic energy sectors (transportation, industrial, agriculture, commercial, residential) and then there are divisions by type (light, electricity, heat). What sort of structure would you suggest? Mrshaba (talk) 18:25, 10 August 2008 (UTC)
The 32KB issue has long been irrelevant and is a distraction from the many other important issues raised in this discussion. I suggest focusing on the real issues below. Geometry guy 21:07, 10 August 2008 (UTC)
The 32 KB issue is still highly relevant and that is why any section or article beyond that gets an automatic size notification when you click edit. People view websites on portable devices, such as cell phones and size can be very important in those cases. Size is a matter of opinion, and is more sensitive to dial-up users or someone who wants to locate information quickly. I would prefer using summary style so that readers can quickly "drill down" to find what they are looking for in the article, instead of keeping one huge article. Wikipedia has no limit to how much material can be included, but as mentioned it may need to be reorganized somewhat. Apteva (talk) 05:45, 11 August 2008 (UTC)

Solar energy is a resource

Solar energy is a resource, and as a resource one of the most fundamental questions is how much is available, both graphically and in comparison to other similar resources. It is essential to not delete that information from the article. And questioning the integrity of the President of MIT? Now that goes way too far. Apteva (talk) 23:58, 6 August 2008 (UTC)

Can you please explain where and how the integrity of the President of MIT has been questioned? Geometry guy 00:47, 7 August 2008 (UTC)
You implicated that she wasn't a reliable source. You don't think she checked her facts first? There are dozens of other sources that make the same statement. She in my opinion happens to have more credibility than the others. Apteva (talk) 01:00, 7 August 2008 (UTC)
I'm sure she checked her facts, but so what? Suppose it were the Queen of England instead of the President of MIT. She would check her facts first before making a statement like that wouldn't she? So can we use her to support the relevance of a comparison between incident solar radiation and global energy consumption? No.
Now read WP:RS, which explains in multiple ways why that source is inadequate to support this image. If this is the best of the "dozens", the image has to go. I actually agree with your basic point about the resource, but you are not addressing it in a way which is compatible with any Wikipedia policy. Find a better way. Based on expert secondary sources. Geometry guy 01:21, 7 August 2008 (UTC)
I'll take a look. Although in my opinion the author is "generally regarded as trustworthy or authoritative in relation to the subject at hand." Digging up a book reference or one from Popular Science should be pretty easy. Apteva (talk) 03:31, 7 August 2008 (UTC)
I've no doubt that the President of MIT is trustworthy, but this isn't her domain; also sources "should directly support the information as it is presented in an article". I have amplified below and thanks for those links. Geometry guy 22:23, 7 August 2008 (UTC)
Evidently the one hour vs one year is a popular quote, although it may be a bit dated as energy consumption and population increase, although in the developed world energy use is projected to decrease by 50% due to efficiency increases (efficiency is going up by about 1% a year - CFLs use 1/3 to 1/4, LEDs about 1/10th the electricity of incandescents, electric cars use 1/7th the energy of ICEs). Here are a few references to choose from. If you googled each variation you would probably find many more: Apteva (talk) 18:57, 7 August 2008 (UTC)

This one quotes Wikipedia 2006 as a source for more in a day than in a year:

This is good progress. Now for step 2 (WP:NOR): which of these sources are the most reliable according to WP:RS? How do the most reliable sources present the information, and how can the article best reflect that? Perhaps multiple sources could be used. Would explicit attribution be helpful? (For instance the physorg.com article says "according to MIT Professor Daniel G. Nocera".)
For me, the two of the above sources which most jump out are the Nature article reprint and the Nature news feature. Nature is clearly a reliable source. Nasa is also not bad and there may be other good ones. Apteva has switched the article's ref to "Physical geography today: A portrait of a planet" by Kolenkow, which may be a good source too, but I haven't checked it myself yet.
At the moment we have two images which make, to my mind, unscientific comparisons. However, if reliable sources present information in a certain way, then our opinions as editors count for nothing. We have to reflect mainstream opinion as far as possible, with explicit attribution if necessary. In this case many sources make the comparison between hourly insolation and annual energy use, so we need at least a sentence on that. I think we even need to say that many sources make this comparison, and cite a few.
Two images, however, represent overkill. Key question: what single image best reflects what the most reliable sources say? It doesn't have to be one of the current two, it can be a new one. We are aiming for a top quality article here. Only the best choice will do. Geometry guy 21:21, 7 August 2008 (UTC)
Judging from your comment about overkill it is possible that the captions need to be made more clear, as each image answers a completely different question - the two questions being, how much is available, and how much do we need? As to the quote I'd veto saying something like "many sources" as it seems highly unencyclopedic. I do agree that the quote shouldn't be buried in a footnote, but it should also have a specific date attached, such as "In 2001,". The Nature article doesn't give any clue as to the origin or basis for the statement, but the Prof. Nocera paper uses a reference of the UN 2003 report "World Energy Assessment Report: Energy and the Challenge of Sustainability". I guess the best thing to do is use two references, the Nature article for the general reader and the Nocera paper for the techies. Apteva (talk) 01:19, 8 August 2008 (UTC)
The first image compares the solar energy available to the energy we need, addressing both questions (in fact, this is one of the main problems with it, as only a fraction of the available energy can be harnessed). The second image also conflates two separate things: the distribution of incident energy (colours), with the energy we need (black dots, under 8% efficiency assumption). The two points should be made separately, and at present there is only space to use an image for one of them. Which point lends itself best to an image? Other points can be made using well sourced prose. Geometry guy 20:00, 8 August 2008 (UTC)
I think an insolation map minus dots would deliver the most bang for the buck. [4] Mrshaba (talk) 20:48, 8 August 2008 (UTC)
I'm not sure that a high res map[5][6] has any value, because weather patterns are not constant, but it definitely has less value without the dots. The main thing to show is in general what are the variations in average insolation, and how much area would be required to replace other sources of energy. As to the first image, I'm more interested in the relation of solar to wind than of solar to consumption. Apteva (talk) 03:26, 10 August 2008 (UTC)
Okay, it looks like we are agreed that the current images don't work. There are two separate issues: comparison of solar with other energy sources, and comparison of solar with consumption. All research into sources so far suggest that the most common comparison or solar with consumption is time-based, not area-based. If Apteva would like to retain an area-based comparison, then reliable sources for such comparisons are needed. The current dot image is too arbitrary to be acceptable at the FA level, unless reliable sources take the same approach. Geometry guy 20:36, 10 August 2008 (UTC)
Huh? Have you clicked on the image? It is well documented, and is completely acceptable for FA or any other level. I'm not sure I understand what you mean by time-based. Apteva (talk) 05:52, 11 August 2008 (UTC)
The image is sourced to a personal webpage, which is not a reliable source. To use the image, we need WP:RS which compare insolation and consumption in terms of surface area. So far, we only have reliable sources which compare insolation and consumption in terms of time (1 hour vs 1 year). Can you provide sources for the area based approach? Thanks, Geometry guy 18:25, 11 August 2008 (UTC)
You are beating a dead horse. The image has been reviewed seven ways to Sunday and is acceptable. Anyone can create an image for WP, it is the data that has to be from a reliable source, not the image. In this case the data source is well documented. Apteva (talk) 17:08, 18 August 2008 (UTC)

Refocus

Article size is a side issue. FAs of 70+KB total size (and 35+KB readable prose) are typical these days, and they can be much larger. FAs must be comprehensive, but should also make appropriate use of summary style. This article is definitely not too long. However, it may go into unnecessary detail in some places. Editors should focus on the level of detail and the need for better spinouts, rather than bean counting. Some history of solar energy is essential in order to make the article comprehensive, but it could be developed in a separate section rather than in each individual section. Let's think about whether the article needs to be restructured, rather than how long it is. Geometry guy 21:07, 10 August 2008 (UTC)

Correct me if I am mistaken, but at the top of this page we have a To-do List presumably developed from peer review for FA status, the top item of which is to reduce size! Now for FA purposes we are told it is not necessary? Can we get clarification here from the FA team and either alter the To-do list or get on with reducing the size as suggested. Jagra (talk) 06:25, 11 August 2008 (UTC)
I have tried to remove that To-do just as I have tried to remove the box diagram. They both reappear. That to do is a distraction. Mrshaba (talk) 06:35, 11 August 2008 (UTC)
Then lets get clarification. Jagra (talk) 06:52, 11 August 2008 (UTC)
You might call it an edit war. I've written most of the page but I have not been able to keep the intro stable, remove the box diagram or control the to-do list among other things. If you go over to the article size talk page you'll see a lengthy discussion of readable prose and whatnot. Apteva goes by Oakwillow over there and he well knows that the consensus regarding page size issues is based upon readable prose. This page has a readable prose of 36 kB and at this length there is no need to have a to-do requiring major size reductions. You worked on the navbox so you know there is a lot of ground to cover within this subject. From my point of view that to-do is a stubborn refusal of consensus both here and on the policy page. As of now the todo list has been updated to reflect the current goals. Mrshaba (talk) 08:32, 11 August 2008 (UTC)
Please, the last thing that anyone needs to do is pretend WP:OWN ownership of a page. Who wrote which short choppy sentences is ancient history and totally unimportant. Apteva (talk) 15:35, 11 August 2008 (UTC)

This has gone on for a year. Mrshaba (talk) 16:45, 11 August 2008 (UTC)

In reply to Jagra's request for clarification, I've updated the todo list (I'm coordinating activity here for the FA-Team). Regarding size, total KBs for FAs with FA-Team support are: 74, 56, 58, 27, 64, 61, 76, 51, 88. These figures are typical for FAs in general, and some are much longer.
At FAC, grumbles about total size start around 100-120 KB, but there are many 100+ KB FAs. The important thing is to be comprehensive without digressing: article size should be determined by the material, not vice versa. Among the FA-Team examples, I am only aware of one case where the FA-Team raised size issues: King Arthur, which was 105KB before FA-Team input, and 76KB afterwards. In most other cases, FA-Team input generally increased article size as missing issues were expanded and references were added. Geometry guy 19:05, 11 August 2008 (UTC)
Thank you for the clarification on Article size, It seems we can now focus on structure. Jagra (talk) 07:37, 12 August 2008 (UTC)
It should be noted that the 2,000+ FA articles range from just over 800 words to just less than 15,000 words with a median (half above, half below) of 3,900 words, corresponding to about 23 kB characters, not the 35 noted above. This article has many sub-articles, and if they were combined into one long article it would far exceed the longest FA article, so I would maintain that a target of less than 40 kB is entirely realistic for the main article, as demonstrated below. There is another warning that kicks in at 80 kB ("This page is 81 kilobytes long. It may be appropriate to split this article into smaller, more specific articles."), and we are below that. Above that is where you start to get most of the size complaints, though articles above 100 kB become very problematic - on dial up they hang your computer for multiple minutes while they are loading. Barack Obama, at 125 KB took 45 seconds just to see the title, and after about 10 and a half minutes locked up the computer with a program error. It only has about 5,400 words (34 k characters), but almost every sentence has at least one reference. After I rebooted I was able to load it partially from cache in 2 and a half minutes. Considering the average attention span on the internet is about 8 seconds, the overblown egos who are working on that article really need to make better use of the 9 subarticles it has, although my recollection is that the campaign subarticle was much longer - about 170 kB. Anyway, enough ranting about other articles. I would stop complaining at anything under 45 or even 50 kB, but I'm on dial up (25 times slower than broadband), so European users with their magical 10+Mb/s won't complain as much. Apteva (talk) 20:26, 12 August 2008 (UTC)

New breakthrough -- 24/7 solar power?

The MIT prof says here that solar cells can collect power all day long. I believe he's referring this paper is important in it. II | (t - c) 20:10, 2 August 2008 (UTC)

Don't bother clicking on either link, all they are are home storage of electricity using hydrogen, which is a horribly inefficient storage medium - about 35%. Pumped hydro-storage is much better - about 78% efficient. Of course you can't do it at home though. That's what the grid and net metering are for. Apteva (talk) 04:57, 3 August 2008 (UTC)
If James Barber, a Fellow of the Royal Society and leading researcher in photosynthesis describes this as "enormous", then hopefully you will pardon my skepticism of your view. I suspect you don't understand it. Then again, I'm no chemist, and don't know much about solar. II | (t - c) 07:01, 3 August 2008 (UTC)
The claim is
"A liquid catalyst was added to water before electrolysis to achieve what the researchers claim is almost 100-percent efficiency."EE Times
I'm skeptical, but I'm not going to dismiss an MIT professor out of hand. Pumped hydro may still be better, but it's not a generally-available option.
On the other hand, I don't buy the idea that this is a particular benefit for solar power, which isn't anywhere close to generating surplus power during the midday. It seems to me that a cheap, efficient means of storing electricity would be a greater benefit to wind power, allowing it to convert an intermittent power source into a reliable, on-demand power supply. Or, on a larger scale, allowing nuclear and coal plants to replace gas turbines in meeting the peak demand, by storing their excess power during the night for the next afternoon.
—WWoods (talk) 14:58, 3 August 2008 (UTC)
Coal and nuclear have absolutely no benefit to society - one causes global warming, acid rain, and mercury poisoning, and the other radiation and nuclear proliferation. All coal and nuclear should be just shut down as quickly as wind and solar with hydro storage can take their place - in 5 to 10 years at most. About the only place in the United States where pumped hydro can't be used is Florida, which may be undersea later on this century anyway. It only requires a 200 foot elevation, though and even Florida has that. If you look ahead to the end of the century, there won't be any coal, nuclear, or Florida left if we follow your proposal. Apteva (talk) 16:15, 3 August 2008 (UTC)
In the meantime gas turbines will replace coal burning as base load unless sequestration proves economic tommorrow. Jagra (talk) 08:05, 6 August 2008 (UTC)
Please confine talk page comments to improving the article, not a general discussion of the merits of solar and other energy technologies. Thanks, Geometry guy 22:13, 6 August 2008 (UTC)
Agree, lets not address POV further, if this is a new energy storage methodology I agree it should be mentioned in the Article, along with pumped storage, now what's the problem with the reference? This PMID 18669820 is an RS ref that I think covers the same finding?Jagra (talk) 07:25, 7 August 2008 (UTC)
Does anyone else think that it is ironic that all the energy research in the US is being done by the National Institutes of Health (nih.gov), instead of by the National Science Foundation (nsf.gov) or the Energy Department (energy.gov)? Apteva (talk) 17:40, 18 August 2008 (UTC)
Just because NIH indexes an article in PubMed doesn't mean NIH conducted or funded the research. It is nothing more than a compilation of article titles and abstracts with bibliographic information. Considering the number of journals indexed in PubMed, NIH probably funded far less than 1% of what you'll find in PubMed.--Squirmymcphee (talk) 00:01, 28 August 2008 (UTC)

It would save a lot of research work if either of them had bothered to set up an electronic database (as done by NIH) of science and engineering papers published in the peer reviewed literature? Apart from other uses it would solve the (seemingly continual) problem of finding reliable source citations for this Article. Jagra (talk) 09:03, 19 August 2008 (UTC)

Can you show an example where another WP article did something similar because this seems like a tall order? One of the primary peer reviewed sources used is the Solar Energy journal. Some of the book refs are also peer reviewed such as Solar Power and Fuels or Passive Solar Buildings. Are you with the FA Team Jagra? Mrshaba (talk) 15:13, 19 August 2008 (UTC)
You didn't need to ask, the list is at Wikipedia:WikiProject Featured articles/FA-Team#Team members and specialities. Non-Cabal members are welcome to edit articles... Please clarify what you mean by "another WP article did something similar". The only discussion I see is about the NIH, not WP articles. Apteva (talk) 18:56, 19 August 2008 (UTC)
This is an indirect DOE database that has been helpful. Sandia Mrshaba (talk) 19:58, 19 August 2008 (UTC)
The sorts of indices you want do exist (e.g., Compendex), but they're privately owned and operated so they generally don't offer free access. You will typically find them in a university library. Between Wiley Interscience, Elsevier, and IEEE Xplor you can cover most of the major journals for free on the web, but then you have go to three different sites to do your searches and you still miss a fair number of notable journals. You might also try Google Scholar.--Squirmymcphee (talk) 00:01, 28 August 2008 (UTC)
I can do searches in the UK Web of Science database, which includes all major science journals in English and many minor ones too. People will need to suggest search terms though, as just searching for "solar" will throw up too many articles to process. Itsmejudith (talk) 09:09, 4 September 2008 (UTC)
Speaking of Google Scholar, editors may find the {{Google scholar cite}} template useful. It acts a storable front-end for searches on the Universal reference formatter. Here are some examples:
Clicking the {{Wikify}} link below a result generates a citation template, such as:
  • Lewis, N. S.; Nocera, D. G. (2006), Proceedings of the National Academy of Sciences, 103 (43), National Academy of Sciences: 15729 {{citation}}: Missing or empty |title= (help)CS1 maint: multiple names: authors list (link)
which might need a little manual editing. I'm thinking about editing a version of the {{fact}} template with options that generate links to example searches using the Universal reference formatter. That way, in addition to displaying "citation needed" (which is fairly useless by itself), a template could show readers how to search for some sources, and generate citation templates with far less effort than the RTFM and manual edit method. --Teratornis (talk) 19:04, 4 September 2008 (UTC)

Reorganization

Lets look at that reorganisation, I agree section 2 seems too long, and I am not sure that 'passive solar' is a technology! Needs to be a definition and more differentiation between 'passive' and 'active' in the Article. Needs to include Industrial solar waste treatment. Perhaps main headings should be (residential, agricultural, commercial, industrial, transportation, storage, development etc )Jagra (talk) 06:49, 11 August 2008 (UTC)

Your idea for naming the sections based on the conventional energy sectors won't work because there's too much overlap. You wouldn't classify coal or natural gas or wind this way. I gave the transportation and agriculture sectors a section but organized the remaining technologies by "type of energy" delivered - i.e. thermal, light, electricity, chemical. The architecture section was my best attempt at summarizing some Passive technologies that didn't fit with the program. This is the basic idea behind the way I organized the page so perhaps we can start from there.
Passive solar is definitely a technology and certainly one of the most important categories in the solar field. The term was coined in the 1970s to contrast against the term 'active solar' which was then the hot thing going. I actually dislike both terms but it's the going lingo. Passive solar homes on average use 70% less auxiliary heat than conventional homes and that takes an impressive amount of passive solar design technology.
Here's a simple problem with passive building technologies when it comes to organization - they're performance is generally measured by a reduction in conventional energy use rather than a production of energy. These technologies simply aren't measured in energy statistics so where do you organize them? You can have passive lighting (daylighting), passive heating, passive cooling or passive ventilation but then you can have active versions of all these technologies too. One idea I had early on was to present the definitions of passive and active right away up in the lead paragraph of the Applications. Here are my definitions.
active solar - Techniques of capturing, converting and distributing sunlight that use electromechanical components such as photovoltaic panels, pumps and fans to process sunlight into useable outputs such as heating, lighting or electricity
passive solar - Non-mechanical techniques of capturing, converting and distributing sunlight into useable outputs. These techniques include selecting materials with favorable thermal properties, designing spaces that naturally circulate air and referencing the position of a building to the Sun to provide solar heating, natural cooling and daylighting.
If these were added the idea of hybrid systems incorporating both features should also be explained.
There's a snippet on industrial solar waste treatment in the process heat section. Interestingly, Namethatworks is a professional technical writer who has done some work in the area of soil remediation. In private communication he suggested we add some more on soil remediation but he withdrew this idea because he didn't feel it was notable enough. I agreed with this because I haven't seen it mentioned in the literature much but I did add the link in the see also list. I don't have any problem with adding this information. Mrshaba (talk) 09:32, 11 August 2008 (UTC)
Long definitions not necessary but identifying passive solar and active solar applications will help, also wikilink in text to Passive house. Some usefull debate on active vs passive here Plenty of RS material on Solar waste water treatment. I will come back with alternative structure for consideration Jagra (talk) 11:05, 11 August 2008 (UTC)
Apteva has indicated (in recent edits to the article) one possible alternative structure. More ideas are welcome. Geometry guy 21:41, 11 August 2008 (UTC)
That would be "edit", not "edits". My intent was to just do a sample and revert it, but I kept it because it came out just fine.[7] At the same time I cleaned up some of the references and added some useful content that had been missing. The agriculture section was mislabeled as "main", those are not subarticles, so it was changed to "{{see}}". The size was reduced to a completely acceptable 37 kB, just by using summary style, instead of folding all the subarticles into the main article as had been done - someone, who boasted that he wrote most of the article, never edited even one other article until recently, not even one of the 16 subarticles. Guys, Wikipedia doesn't assign you an article for you to only be able to work on that one - use subarticles - that's what they are for. And if your employer assigned you to work on the article, that's really bad for WP. At 37 kB it took me 20 minutes to read and that's really the upward limit that I would like to see in one article. Apteva (talk) 22:21, 11 August 2008 (UTC)

Predicated on the longer Article I had in mind a more expanded content. Without going into detail at this time as to what goes under which section, it would look something like this;

Contents

1 Energy from the Sun

Solar radiation, Insolation

2 Agriculture

Agriculture, Horticulture, Greenhouse

3 Buildings

Passive solar building design, Passive house, Zero energy building, Thermal mass, Urban heat island, Passive solar, Active solar

4 Residential and Commercial

Solar heating, Solar hot water, Solar combisystem, Solar air conditioning, Solar chimney, Solar lighting, Solar cooker, Solar still, Solar water disinfection,

5 Industrial

Desalination, Process heat, Solar chemical, Solar waste conversion, Soil solarization

6 Solar Electricity

7 Transportation

8 Energy storage

9 Experimental

10 Development, deployment and economics

11 See also

12 Notes

13 References

14 External links

I think Apteva's work could fit into this structure, extending the summary style, I am open to suggestions, hack away. Jagra (talk) 07:31, 12 August 2008 (UTC)

It's more common to break up the technologies along energy boundaries or applications. Residential, Commercial and Industrial do not break up the topic in a meaningful way. Does this make sense? This application breakdown should be helpful: [8] I think breaking down the technologies by energy qualities is more fundamental and easier to understand. The paper by Cedric also offers an excellent overview of thermal technologies. [9] Mrshaba (talk) 16:33, 12 August 2008 (UTC)
I'm not so sure it is so common, The logic is difficult to follow and that is probably why section 2 is so convoluted with too many sub headings and sub sub headings, It needs a fresh structure, regardless of the size issue. In the structure suggested above, any more than say a max of three Main article links is unweildy. It should be summary style (which there seems to be some consensus on) and a simple matter of including the leads under the sub headings. Clearly from the structure I have outlined above there is more than enough available material to do just that. In fact in Residential and Commercial as well as Industrial new sub articles are probably needed. I don't agree with listing unused material in the See also section, I see this as for related but not directly relevant links. In the Buildings section you could cherry pick for main articles but mention and link others in the text, rather than as at present denying their existance. Does that make sense? Jagra (talk) 05:33, 16 August 2008 (UTC)
Sorry, your proposal doesn't make sense to me. What does this mean? "In the structure suggested above, any more than say a max of three Main article links is unweildy."
I favor modifying the current structure rather than starting with something completely new. The Cedric paper above is an excellent example of grouping solar thermal technologies together and he uses many of the same sub-headings in his breakdown as are used on the page. I don't see this as unwieldy. Grouping these technologies by energy sector does not make sense to me and strangely it seems as though I suggested it to you in the conversation above. Daylighting applies in all energy sectors and putting it in say Residential implies it's not or cannot be used in Industrial. The same goes for solar heating and solar water heating. These technologies don't breakdown in that way. The energy sectors are artificial to begin with. Breaking the technologies down by energy qualities makes a whole lot more sense.
"I don't agree with listing unused material in the See also section." It's a notability thing. There are dozens of solar technologies that are not listed on the page because the don't meet the bar - distillation pyramids for example. A professional writer that worked on a solar soil remediation project felt it wasn't a notable technology so it was skipped. No one is actively denying the existence of any individual technologies. Mrshaba (talk) 16:32, 16 August 2008 (UTC)
It would be easier for me to visualize what you had in mind if you just went ahead and edited the article - even if you don't fully fill in all the sections - save it and then revert yourself using undo if you have only stubbed the sections, keep it if you have a workable version. Then you can post the version link here for us to see, like this one.[10] Apteva (talk) 17:22, 18 August 2008 (UTC)
When i see some making value judgements about other Articles with comments like 'because they don't meet the bar' in order to justify their own position, I am tempted to comment that this Article is not yet of a standard from which to judge others. That is what we are working towards, and why a restructure is needed. Regarding this comment, Daylighting applies in all energy sectors and putting it in say Residential implies it's not or cannot be used in Industrial. I could say well wheels and engines apply to all vehicles but we catergorize them as, cars, trucks, busses, etc. It goes without saying that certain aspects apply to others, and i do not see this as problematic. I am beginning to think that this Article might be better titled 'History of solar power' and a complete rewrite done for Solar power, in the meantime i will give consideration on beginning with a few sections. Jagra (talk) 09:27, 19 August 2008 (UTC)
I would agree with that, but it's a toss up as to whether to use page move or create History of solar power using cut and paste, because everyone "thinks" they were working on the "solar power" article while they were editing this "history" article. I would recommend cut and paste. But don't do it until you have heard from others. Apteva (talk) 19:07, 19 August 2008 (UTC)

Why shouldn't this article include examples of environmentalist opposition to solar power?

I added 3 examples of environmental opposition to solar power to this article, but an unregisitgered user moved them to the Solar power in the United States article. I think they should be included here, because this article should be balanced. Grundle2600 (talk) 20:05, 22 August 2008 (UTC)

The article seems to be against the route transmission lines would take in a special situation rather than solar energy in general. The vast majority of installed PV either completely eliminates the need to run transmission lines (off-grid) or is built adjacent to the existing grid (Nellis, Rancho Seco, grid-connected homes). The location for the huge project PG&E recently announced was chosen specifically because it fell alongside the existing transmission lines running out of Diablo Canyon. The PV guru Martin Green has argued that PV reduces the need to expand transmission capacity because it is generally sited closer to end users thus reducing the load on the lines. So, I don't think the article is representative of the way PV is generally sited. It's also rather vague when it comes to details that specifically relate to solar energy. Do you have any other sources that mention this issue? Mrshaba (talk) 22:22, 22 August 2008 (UTC)
See here

"But David Hogan, a San Diego-based conservation manager at the Center for Biological Diversity, questions SDG&E's math.

"The Utility Conservation Action Network has shown SDG&E has wildly underrepresented the cost. It's going to be much more than $1.5 billion and much less for (installation) of rooftop solar," Hogan said.

Judging from this quote it seems CBD is arguing for rooftop solar installations vs. a remote facility. So again, the opposition is not focused around solar energy but a transmission line. Mrshaba (talk) 22:47, 22 August 2008 (UTC)
It's also uniquely applicable to the United States, and just deals with the permitting process there, and of no interest to anyone from say, England, Germany, France, Spain, Australia, should I go on? That is why it was moved to the appropriate article - SP in the US. Anyone who argues that rooftop solar is cheaper than CSP doesn't know what they are talking about, by the way, which they would quickly learn if they read a few WP articles on the subject. 199.125.109.134 (talk) 02:33, 23 August 2008 (UTC)
For comparison, Environmental effects of wind power is a collection of (seemingly) every sort of environmental or aesthetic objection to wind power. Having a separate "Environmental effects of ..." article allows the primary article to summarize these effects, and avoid becoming a battleground. Anyone who wants to really understand any form of commercial-scale power generation (whether centralized or distributed) needs to be familiar with all the objections to it that various people have dreamed up in various places. The solar power folks in, say, Germany certainly need to pay attention to disputes over solar power in the U.S., if only to be sure their local conditions are sufficiently different to preclude the same kinds of disputes. Market conditions in one country may affect companies in another country, due to international trade (for example, the U.S. imports thousands of wind turbines from European countries such as Vestas, so those companies have to care about energy policy in the U.S. which could affect wind turbine sales). Every form of commercial-scale power has some sort of environmental or social impact. Even though the side effects of solar power may be negligible in comparison to the potentially disastrous effects of large-scale fossil fuel drawdown, the side effects are not zero, and belong in any comprehensive treatment of the subject. Although of course we don't have to cram everything into the main article on a subject, when we can have any number of subsidiary articles to treat the side topics. --Teratornis (talk) 07:24, 21 September 2008 (UTC)

Solar Waste water treatment

Added a new section to the Article, glaring ommission previously but it does not readily fit into existing structure, so have added it at end of Article. Feel free to relocate it.

This is one reason a new structure is needed, I will post and revert for discussion a proposed new structure edit soon that will present better and provide for this section. Jagra (talk) 07:26, 29 August 2008 (UTC)

I think it belongs in the existing section Desalination and disinfection, but will wait for other views. It could also be shorter and I'm not sure that it is relevant to discuss whether it is better to desalinate or to treat waste water. So much depends on the location and the purpose of treating the water, and the question may be independent of whether solar methods are used. Also, if we go into too much length we start to raise more questions, e.g. why would such a method be used in preference to a reed bed or related method of filtration - and since reeds need sunlight to grow, is a reed bed a solar technology anyway? Best short and sweet and within the existing section. Will be interested to read your proposals for a new structure, but I'm not convinced that we will ever be able to find a universally agreed taxonomy for this diverse group of technologies. Nice to see peace breaking out on the article while I was away and that there are new editors around. Itsmejudith (talk) 21:09, 3 September 2008 (UTC)

What to do now for FA?

Hi everyone. Progress on the article seems to have stopped. I am not sure why a restructuring is necessary or whether any of the things on the to-do list are still outstanding. I would like to see the article resubmitted for judgement as soon as possible. Also, although I dread to raise this, is there now consensus on the illustrations. I thought there was consensus that the box diagram was misleading and should go????Itsmejudith (talk) 12:57, 17 September 2008 (UTC)

It has been suggested that this article be cut and pasted into History of solar power and the article be restructured, taking out all the duplication from all the sub-articles. If you look at the SEIA (Solar Energy Industries Association) website, there are only four ways to use solar energy: "There are four ways we harness solar energy: photovoltaics (converting light to electricity), heating and cooling systems (solar thermal), concentrating solar power (utility scale), and lighting." Normally unless something has radically changed there is no point in resubmitting an article right away. Apteva (talk) 01:18, 19 September 2008 (UTC)
I'm perfectly happy to have a History of solar power article, but I don't think that very much of this article should go into it. And I'm not particularly impressed by the SEIA idea that there are exactly four ways we harness solar energy. That is one way of grouping the technologies, but it is only one way. It also leaves out solar water purifiying, desalination and several other applications we mention here. Itsmejudith (talk) 18:34, 19 September 2008 (UTC)
The SEIA grouping also leaves out hydropower, wind power, and agriculture which are other ways we use solar energy. Fossil fuels represent stored (ancient) solar energy according to mainstream geological theory. Most energy available to humans derives ultimately from solar energy, with some exceptions including nuclear power, geothermal power, and tidal power. However, by convention we usually consider the indirect applications of solar energy to be separate topics. Thus the SEIA should not say "there are only four ways" but rather, "We find it convenient to arbitrarily recognize four of the ways..." --Teratornis (talk) 18:28, 20 September 2008 (UTC)
Oops, I noticed the quote from the SEIA says "There are four ways...", and does not say "only." The word "only" appears to reflect Apteva's reading of the quote. The phrase "there are four" may be technically correct if there are at least four, but many people might read it as exactly four, as I did initially. --Teratornis (talk) 18:35, 20 September 2008 (UTC)

I was reviewing part of the SEIA website and noticed this page. [11] They combine solar lighting in with Passive Solar and leave out some sections (Chemical, Agriculture, Vehicles) but there's plenty of organizational overlap and I'd say this tends to validate the basic layout of the technologies on this page. Mrshaba (talk) 08:11, 8 October 2008 (UTC)

12-Year-Old May Hold Key to Solar Energy

http://news.yahoo.com/s/zd/20080919/tc_zd/232218 Bioye (talk) 14:18, 20 September 2008 (UTC)

That article seems to have been written by a reporter who knows little or nothing about physics or solar energy. It makes the extraordinary claim: "...one 12-year-old boy may have the key to making solar panels that can harness 500 times the light of a traditional solar cell." The only way to get more light to a solar cell is to use some sort of mirror or lens to concentrate the light, but the article says nothing about that. Thus the "500 times" statement makes little sense, since "traditional solar cells" already harness about one fifth of the incident light energy. One fifth is one hundred times greater than one five hundredth as the article implies. The rest of the article rambles vaguely without explaining the bizarre claim it opens with. Unfortunately, popular press accounts of the field of energy have some examples of poor writing, which both result from and prey on the general public's lack of understanding of basic concepts from physics and engineering. For example, see Water-fuelled car and Perpetual motion machine. If you can find some reliable sources that describe this 12-year-old boy's invention coherently, you can work them into the appropriate article(s) on Wikipedia. The link you gave does not appear to be a reliable source, at least with respect to its claim about the conversion efficiency of this solar cell. The source may be reliable about the name of the boy and the award he won, since the reporter needs no special training to relay those facts correctly. --Teratornis (talk) 18:13, 20 September 2008 (UTC)
I should add that people do not necessarily judge the work of a 12-year-old as they would judge the work of an adult. When an adult invents something, we want to know whether it works. When a child invents something, we want to know what the invention says about the inventive potential of the child - whether the invention actually works or could reach commercial scale is secondary, because we're thinking about what the child will do in the future. When I was a child, I cooked up some fantastic ideas too, but none of them amounted to anything. It would be very hard for a child to produce a real breakthrough in the field of energy technology, because the field is very mature, and thus a child needs years of training just to catch up to current practice in some particular area. By the time the child knows enough to actually innovate, the child is usually an adult. --Teratornis (talk) 18:41, 20 September 2008 (UTC)
http://www.davidsongifted.org/fellows/Article/Davidson_Fellows___2008_405.aspx#table14 says
"In his project, “High Efficient 3-Dimensional Nanotube Solar Cell for Visible and UV Light,” William invented a novel solar panel that enables light absorption from visible to ultraviolet light. He designed carbon nanotubes to overcome the barriers of electron movement, doubling the light-electricity conversion efficiency. William also developed a model for solar towers and a computer program to simulate and optimize the tower parameters. His optimized design provides 500 times more light absorption than commercially-available solar cells and nine times more than the cutting-edge, three-dimensional solar cell." [emph added]
The "doubling" claim is extraordinary, but not impossible. I don't know what the "500 times" figure is supposed to mean. Maybe only 1/500th as much is not being absorbed?
—WWoods (talk) 00:03, 21 September 2008 (UTC)
The only way I see to make sense of the "500 times" is to assume "solar towers" refers to placing the solar cell at the focus of a Solar power tower. Thus the solar cell would have to be extremely durable. The first article still sounds a bit overblown because the total system cost for a solar power tower would still be high, even if putting solar cells at the focus would be cheaper than using a thermal collector. You still need the heliostats and so on. Or maybe a hybrid system could use both, by cooling the solar cells with a working fluid that could then drive a heat engine. One advantage of the solar power tower is its ability to store heat energy in a reservoir of working fluid, allowing it to generate electricity for several hours after sunset. The thermal system also buffers brief interruptions in sunlight due to passing clouds, whereas photovoltaic cells would vary all over the place. Even if solar cells double in bang per buck, they still cost more than modern wind turbines. Still, this item is interesting and might go into some subsidiary article, perhaps if we get a more coherent description of what exactly the young inventor came up with, and what effect it could have on the industry. (Although WP:CRYSTAL may apply.) --Teratornis (talk) 07:06, 21 September 2008 (UTC)
I don't see any need to put it in the article at all. On the other hand the CSP article needs a better explanation of concentrating solar power using photovoltaics (here is the entire body of the article: "Technologies: Concentrating solar thermal (CST) and Concentrating PV (CPV) are the Concentrating solar power technologies.") - there is one company that I know of that is using a 1,000 to 1 concentration on the photovoltaic cell, using a parabolic mirror in two axes to concentrate the sunlight onto a 2.5 x 2.5 (approx) cm photocell. It also provides an equal amount of heat output - for every 1 kW electricity, they provide 1 kW heat as well, in the form of hot water. When you think about it, concentrating photovoltaics makes a lot more sense than flat panel photovoltaics, because for the price of a piece of 1/8th inch plywood and a roll of aluminum foil you can effectively multiply the efficiency of your silicon by a factor of 10 or even 100. You are not getting any more energy per square meter of land area, but you are concentrating the sun onto a smaller area and using less silicon for the same power output. The solar field is robust, but has a lot of evolving left to do, and somewhere between 1 and 1,000 an optimum number will eventually fall out (I think a fresnel lens gives a concentration of 2 or so). In reading the article, what the 500 number means is that the 12 year old is concentrating the sun by 500 and shining it on a complex surface with nanotubes etc just like a multilayer photovoltaic cell to extract a higher efficiency than available from a single cell solar panel. Apteva (talk) 01:11, 23 September 2008 (UTC)

Adding and Removing

After reading through parts of the page today it seems there's some questionable material. I don't really know who contributed the material. The edits have consisted largely of vandalism recently and I don't have the will to go through each edit by edit since August. Here's some material that I think can be removed or truncated.

While comparing ocean water desalination to wastewater reclamation for drinking water shows desalination as the first option, using reclamation for irrigation and industrial use provides multiple benefits.[48] Urban runoff and storm water capture also provide multiple benefits in treating, restoring and recharging groundwater.[49]Solar energy is being used in treating waste water for reuse.

Sunlight enables waste water stabilisation ponds to disinfect wastewaters very effectively without the need for any chemicals or electricity consumption and their associated CO2 emissions. The energy and carbon emission savings gained over electromechanical treatment systems are immense. Furthermore, because algal photosynthesis consumes CO2, WSP can be utilised as CO2 scrubbers, and provide an energy source. [50] [51]

Tests on two solar-driven advanced oxidation processes, namely heterogeneous semiconductor photocatalysis and homogeneous photo-Fenton, both coupled to biological treatment, were carried out in order to identify the environmentally preferable alternative to treat industrial wastewaters containing non-biodegradable priority hazardous substances. The experimental results obtained showed that solar photo-Fenton is able to obtain a biodegradable effluent much faster than solar heterogeneous photocatalysis. [52] Combined solar photo-Fenton / biological treatment is being used or considered for removal of endocrine disrupting chemicals in sewage treatment waste water. [53] for treating industrial effluents [54] including treatment of winery waste water [55] for the bleaching wastewater effluent from a pulp and paper mill [56] tannery wastewater.[57] and textile dyeing wastewater. [58][59] The technology is also being used for the treatment of groundwater contaminated with benzene or petroleum such as at garage sites. [60][61]

The use of PV for extended purposes shouldn't take up too much space on the page. Unique/dominant technologies like remote lighting, water pumping or powering vehicles might deserve mention but PV powered water cleaning isn't particularly interesting to me. I like the bit about decontamination ponds but the picture throws me off. I think this should be compressed into half the space.

The High-altitude airship (HAA) is an unmanned, long-duration, lighter-than-air vehicle using helium gas for lift, and thin-film solar cells for power. The United States Department of Defense Missile Defense Agency has contracted Lockheed Martin to construct it to enhance the Ballistic Missile Defense System (BMDS).[126] Airships have some advantages for solar-powered flight: they do not require power to remain aloft, and an airship's envelope presents a large area to the Sun.

This is a future project. I know Space power is already on the page but the line on future technology needs to be drawn.

Solar installations in recent years have also largely begun to expand into residential areas, with governments offering incentive programs to make "green" energy a more economically viable option. In Canada the government offers the RESOP (Renewable Energy Standard Offer Program).[citation needed] The program allows residential homeowners with solar panel installations to sell the energy they produce back to the grid (i.e., the government) at 41¢/kWh, while drawing power from the grid at an average rate of 20¢/kWh (see feed-in tariff). The program is designed to help promote the government's green agenda and lower the strain often placed on the energy grid at peak hours. With the incentives offered by the program the average payback period for a residential solar installation (sized between 1.3 kW and 5 kW) is estimated at 18 to 23 years, considering such cost factors as parts, installation and maintenance, as well as the average energy production of a system on an annual basis.[citation needed]

Daniel Lincot, the chairman of the 2008 European Photovoltaic Solar Energy Conference and the research director of the Paris-based Photovoltaic Energy Development and Research Institute, said that photovoltaics can cover all the world energy demand [145]. Photovoltaics are 85 times as efficient as growing corn for ethanol. On a 300 feet by 300 feet (1 hectare) plot of land enough ethanol can be produced to drive a car 30,000 miles (48,000 km) per year or 2,500,000 miles (4,020,000 km) by covering the same land with photo cells.

The PPA material is poorly sourced and seems to be misrepresented. I don't like all the subsidy information because everywhere is different as far as subsidies go. I like the example about cars driving but I think it's misplaced in this section. Perhaps a performance section? Anyways, I'm leaving for Tokyo in the morning. Good luck with the page. Mrshaba (talk) 00:47, 11 October 2008 (UTC)
In general the page is still horrendously long, about 84,000 bytes, instead of the 40,000 that would be acceptable in my opinion. I think a lot can be done by making use of the many subsections that we have. Have fun in Japan. There is no Solar power in Japan article, a glaring omission. Maybe you can find someone who can help create it. I would suggest taking along a print out of the solar power in Germany and in the United States articles as samples. Apteva (talk) 03:07, 11 October 2008 (UTC)
I noticed that you deleted the sentence "Solar lights that charge during the day and light up at dusk are a common sight along walkways." This is odd because for most people, that is by far the most common use of solar energy. I would recommend keeping it in. Apteva (talk) 04:25, 12 October 2008 (UTC)
That's a detail that might have an application in the body of the text, but is not appropriate for the lede. --Skyemoor (talk) 11:39, 12 October 2008 (UTC)
That's where it was. I'll put it back. I would have taken it out myself if it had been in the lead. All of this section is only about the body of the article. Apteva (talk) 13:46, 12 October 2008 (UTC)
Re the stuff that Mrshaba mentioned at the beginning of this thread. This was a chunk about waste water treatment added a few weeks ago. There was a question about where it should go in the article. I suggested it should go with the other water treatment (disinfection and desalination). There was no reply so I went ahead and moved it. But it is far too long, for what is not a very developed technology. I'm going to shorten it drastically. Itsmejudith (talk) 16:30, 12 October 2008 (UTC)