Talk:Solar water heating

message: Can you please put more pictures in this article? 130.49.162.62 19:32, 29 October 2006 (UTC)
thread_title:  Pictures 

message: Here is a link to a great solar hot water heating site http://www.solarroofs.com/Makingitbetter7 06:34, 15 December 2006 (UTC)
thread_title:  Link to buy solar hot water heaters. 

message: An schematical image is to be added to the article to make things more clear.
At *Solar hot water system schematical picture and especially at another schematical picture of a solar hot water system (page 22), there are 2 good pictures. Is it possible to upload them at the top (where the "no picture available" is located ?
These pictures are incorrect - please refer to link on picture and associated comment.
I dont know whether the picture may be taken from the brochure and simply modified with a program (GIMP, ...). Perhaps that this is possible and legal (OND Vlaanderen is a governmental information company) and that the picture may be thus modified and uploaded at a legal way.
KVDP (talk) 15:12, 9 February 2008 (UTC)
thread_title:  Image request 

message: I believe that "Solar water heating" would be a more appropriate name for this article. --213.149.123.28 (talk) 23:11, 13 February 2008 (UTC)
thread_title:  Name change 

message: With ever rising diy-community and their increasing environmental awareness, people have begun building their own (small-scale) solar hot water systems from scratch. Trough the internet, the community is able to attain plans to solar hot water systems. Solar hot water DIY systems/plans from the PESN-database3 other diy solar panels from the Sietch and people have sprung up building them for their own domestic requirements. The DIY-solar hot water systems are being used both in the developed world, as in the developing world to power homes.
I'm already putting this section in, hope it qualifies (it would be very helpful for the green community so try to improve it before deleting it, if you were tempted to this.
KVDP (talk) 12:18, 18 February 2008 (UTC)
thread_title: DIY Solar Hot Water Systems 

message: * Dutch Useful publications on solar hot water systems with drawings and explications of practically set-up systems). Notable publications with pictures include: "Zonneboilers - warm water met de zon", Ideeen voor energiezuinig bouwen (useful picture hot water solar plate and tank), "Energieprestatieregelgeving: Praktische gids voor als u binnenkort gaat bouwen of verbouwen (pricing commercial hot water systems + installation by third party)" 
Another useful schematic is present in this document (page 22) 
See to the links mentioned, include info in article.
KVDP (talk) 10:05, 30 March 2008 (UTC)
thread_title:  Link to obtain extra info and pictures, ... 

message: A picture of a batch water heater would be useful here. I saw a very nice one at the book "Earthship volume 2", but this one is useful too.  —Preceding unsigned comment added by 81.246.142.204 (talk) 13:50, 28 August 2008 (UTC)
thread_title: Batch water heater picture

message: Someone removed the schematic and upped other picture. As the first was useful with this other one (included operation within a house with extra components, I reuploaded :
Do not remove; lots of cooperative work has been gone in this (I spent lots of hours on it too). Thanks;
KVDP (talk) 16:49, 28 August 2008 (UTC)
thread_title: Schematic

message: The pictures at http://www.appropedia.org/Solar_hot_water_-_system_types (Examples of Common Solar Hot Water Systems) can speficiy the difference between open and closed loop active systems. Please include in article.
Also, can someone improve my batch heater (thumb|right|150px) and upload to article again  —Preceding unsigned comment added by 81.245.182.116 (talk) 16:06, 11 February 2009 (UTC)
thread_title: Pictures

message: Is a unglazed collector a flat plate collector. If so, add this article to text:
Also add following images where applicable:
Image:Evacuated tube diagram.jpg
Image:Active_closed_loop_solar_HW_system.gif
Image:Active open loop solar HW system.gif
A text explaining the difference between the open loop and closed loop systems should be added. Some info can be found at Appropedia-system types  —Preceding unsigned comment added by 81.245.168.190 (talk) 10:36, 12 February 2009 (UTC)
thread_title: Unglazed equals flat plate collector ?

message: The comparison at http://njwolf.iweb.bsu.edu/solarhotwater.htm can be integrated to page.
Also, recategorise the page, for example drainback systems are a very important category spanning over some of the mentioned (uncategorised) systems on the page. Some additional info is available at http://www.house-energy.com/Solar/System-Drainback.htm  —Preceding unsigned comment added by 91.176.218.77 (talk) 15:58, 7 September 2009 (UTC)
thread_title: Solar water systems comparison

message: Earlier today, I added a link to a new company that I'm working with called Zoe Energy (www.zoeenergy.com).  The company just started about 2 weeks ago and is planning on including discussions surrounding alternative energies.  I think it would probably be useful to Wikipedia to include linked to this "type" of site. Rangerwez (talk) 19:11, 10 September 2009 (UTC)
replies: text: Please don't add links to companies that you're working with, see the conflict of interest guideline. Even setting that aside, commercial sites are usually not going to be linked. See the guideline on external links. - MrOllie (talk) 19:18, 10 September 2009 (UTC)
thread_title:  Linking to External Sites 

message: I propose we merge the collector section here into Solar thermal collector and reduce this section to list (and link to) the types of collectors that are used for heating water (as opposed to producing thermal electricity).Jojalozzo (talk) 15:55, 22 January 2010 (UTC)
thread_title:  Solar Thermal Collector subsumes Collector section here 

message: These new diagrams while excellent otherwise have the low side sensors detecting the return temperature on the heat exchanger. In my experience the sensor for the low side of the differential controller is placed in the storage tank near the heat exchanger to detect the temperature of the potable water at that location in the tank. Jojalozzo (talk) 13:57, 7 February 2010 (UTC)
thread_title:  Indirect active system image sensor location 

message: This section is unnecesary and undue weight. Perhaps a new article can be created with it? LK (talk) 10:35, 11 February 2010 (UTC)
thread_title:  History of solar water heating in Israel 

message: Levi Yissar built the first prototype Israeli solar water heater and in 1953 he started NerYah Company, Israel's first commercial manufacturer of solar water heaters.Solar Evolution - The History of Solar Energy, John Perlin, California Solar Center.Petrotyranny by John C. Bacher, David Suzuki, published by Dundurn Press Ltd., 2000; reference is at Page 70  Despite the abundance of sunlight in Israel, solar water heaters were used by only 20% of the population by 1967. Following the energy crisis in the 1970s, in 1980 the Israeli Knesset passed a law requiring the installation of solar water heaters in all new homes (except high towers with insufficient roof area). As a result, Israel is now the world leader in the use of solar energy per capita with 85% of the households today using solar thermal systems (3% of the primary national energy consumption).The Samuel Neaman Institute for Advanced Studies in Science and Technology - Publications - Solar energy for the production of heat Summary and recommendations of the 4th assembly of the energy forum at SNI
Israel's use of solar water heaters is estimated to save the country two million barrels of oil a year, and the country has the highest per capita use in the world.Israeli Section of the International Solar Energy Society, edited by Gershon Grossman, Faculty of Mechanical Energy, Technion, Haifa; Final draft. In the 1950s there was a fuel shortage in the new Israeli state, and the government forbade heating water between 10 p.m. and 6 p.m.  As the situation worsened, engineer Levi Yissar proposed that instead of building more electrical generators, homes should switch to solar water heaters.  He built a prototype in his home, and in 1953 he started NerYah Company, Israel's first commercial manufacturer of solar water heaters.  By 1967 around one in twenty households heated their water with the sun and 50,000 solar heaters had been sold.  However, cheap oil from Iran and from oil fields captured in the Six Day War made Israeli electricity cheaper and the demand for solar heaters  dropped. With the 1970s oil crisis, Harry Zvi Tabor, the father of Israel's solar industry, developed the prototype solar water heater that is now used in over 30%-40% of Israeli homes.At the Zenith of Solar Energy, Neal Sandler,BusinessWeek, March 26, 2008.  
In 1980, the Israeli Knesset passed a law requiring the installation of solar water heaters in all new homes (except high towers with insufficient roof area). As a result, Israel is now the world leader in the use of solar energy per capita (3% of the primary national energy consumption).The Samuel Neaman Institute for Advanced Studies in Science and Technology — Publications — Solar energy for the production of heat Summary and recommendations of the 4th assembly of the energy forum at SNI
As of the early 1990s, all new residential buildings were required by the government to install solar water-heating systems, and Israel's National Infrastructure Ministry estimates solar panels for water-heating already satisfy 4% of the country's total energy demand.  Israel and Cyprus are the per capita leaders in the use of solar water heating systems with over 30%-40% of homes using them.Summary of solar thermal capacity
I do not agree at all.The historical importance of Israel in developing and implementing solar thermal devices is undisputed. The historical context would be incomplete without a section on Israeli technology development. Their skills have been exported to many other countries. However, your point about weaknesses in the text has merit. I have shortened the Israeli section, reorganised the HISTORY section, hope this improves the content.
Jwhferguson (talk) 18:57, 11 February 2010 (UTC)
thread_title:  Israel 

message: I am adding in a new type of pumping system I found on the web under active -- I am not sure if it would be better placed under passive -- although it does not use electricity to run the pump it isn't using convention as in a thermosiphon either....and is using a pump. Someone more experienced with solar thermal system - please make sure it is in the appropriate category.Enviro1 (talk) 13:54, 10 June 2010 (UTC)
thread_title:  active/passive bubble pumping system 

message: The initialism HCF is not defined at its first use.
Please clarify the meaning of HCF. - Ac44ck (talk) 00:33, 3 October 2010 (UTC)
replies: text: Thanks to Jwhferguson for fixing the typo to HTF. -Ac44ck (talk) 06:54, 7 November 2010 (UTC)
thread_title:  HCF 

message: It has happened, with a number of solar water heating installations, that the water temperature rose to nearly 100 degrees C, during intense solar radiation and low hot water demand: High water temperatures caused plastic plumbing to rupture. This problem calls for methods of cooling the tank water when temperatures of about 90 degrees are reached. An easy way to do this is to force-circulate the tank water through a radiator device (similar to heating radiators) placed in a shady and well ventilated location. Care should be taken that the materials the radiator is made of be suitable for handling drinking water. Alternatively, the fluid of the heat exchanger, if such is used, be circulated through the radiator, but in this case electrically operated valves should be used to isolate the heat exchanger circuit from the solar collectors.  —Preceding unsigned comment added by 62.38.220.132 (talk) 08:51, 28 March 2011 (UTC)
replies: text: This will not happen in a drainback flat-plate system, and it is extremely unlikely that it will happen even in an antifreeze flat-plate system.  However, if you go on vacation and have an ICS, ICS-thermosiphon, or a system using evacuated tubes, yes, it's possible that you could come home to a disaster.  It sounds like you have a FAFCO antifreeze system, though, since it has "plastic plumbing" in it.  At any rate, your system should be protected from this type of damage from the T&P valve, but people often neglect their T&P, leading to sometimes catastrophic results.  My advice would be to replace your T&P valve since it most likely failed to do its job.  (The other possibility is that your T&P is actually working, but your system failed long before the boiling point, which is possible, given that it is plastic.)  SolarCoordinates (talk) 18:28, 15 April 2011 (UTC)
thread_title:  Overheating 

message: The choice of making flat-plate collector risers small has little to do with the "surface-to-volume" ratio, and is instead based upon (1) shortening the distance between the absorber fins' center point and the riser pipe, as decreasing this distance increases thermal conductivity, reducing heat loss, and (2) the same size as the headers would cause uneven flow across the risers: the risers near the outlet would have much higher flow than the risers near the inlet.  SolarCoordinates (talk) 09:23, 20 April 2011 (UTC)
thread_title:  "Since the surface-to-volume ratio increases sharply as the diameter of a pipe decreases" 

message: I changed the article because, for example, the definitions of direct & indirect were buried in the "Passive Systems" section even though they are completely independent of passive/active.  Freeze & overheat protection also had their own section under "Types of Solar Water Heating (SWH) Systems)" even though they aren't "types" at all.  Changes were mainly structural in nature, but some content was changed as well.  If you have any concerns about the changes that were made, PLEASE POST THEM HERE.
More changes will be coming since, for example, ICS is defined in two different places, and there is also a small "history" section under "Collectors used in modern SHW systems," which seems unnecessary.  I am also not a fan of the "140 kWh per month" table, as that represents a mediocre system installed on a two-person residence, which should not be considered representative of a typical installation.  Additional sections will be made to address concerns for future changes. SolarCoordinates (talk) 21:37, 20 April 2011 (UTC)
thread_title:  April 20 Overhaul 

message: Regarding the "Costs and payback periods for residential SWH systems with savings of 200 kW.h/month (using 2010 data)" chart:
The following is updated data obtained in August 2011:
Country: Israel
Currency: NIS
System Cost: 3,200
Subsidy: 0%
Effective cost: 3,200
Electricity cost/kW.h: 0.52
Electricity Saving/month: 104
Payback period(y): 2.6
I would have put the data in myself but could not find how. 84.229.231.234 (talk) 19:20, 16 August 2011 (UTC)
thread_title:  Financial data for Israel 

message: Converting all of the costs to US Dollars (using 2010 exchange rates, same as date of data) would make this table much more useful. Any objections?  — Preceding unsigned comment added by Markg729 (talk • contribs) 19:40, 10 October 2011 (UTC)
thread_title:  Costs and payback periods table --> USD 

message: Its should probably be pointed out that for most people the savings gained from installing a solar hot water heater are questionable at best. This is because most people use most of their hot water either in the early morning or in the evenings when a solar collector is not producing hot water. Let me elaborate. Lets say that all the members of your family shower in the morning, effectively using most of the stored hot water. Now, since the solar collectors have not yet heated up, the back up gas or electric heater will automatically come on and stay on until the entire 40 gallons in the water tank is hot again. By the time the solar collectors are ready to produce there job is already done. And if you shower in the evening it’s the same story, as the sun is going down by then. The only thing the solar collectors will be doing in this case is replacing the heat that dissipates from the tank during the day. The gas or electric heater on the other hand will be making ALL the hot water used by you and replacing all the heat dissipated from the tank during the night. So basically this means you could actually save more money by installing a tankless hot water system, which heats water on demand, than by installing a solar system. Of course if your family uses most of their hot water in the afternoon then a solar system could definitely save you a substantial amount on your hot water heating cost. I suspect that when the solar industry gives out statistic on potential savings they are basing those savings on these afternoon energy users, which of course is very misleading to the rest of us. Don’t get me wrong, complete home solar heating systems can be great, be they passive or active. They are usually able to store all the energy gained from the sun during the day and release it back into the house during the night. Solar hot water heaters alone on the other hand are probably a big waste of money for most people though. Slobeachboy (talk) 05:43, 21 January 2013 (UTC)
replies: text: Great. WP:BOLD, cite it and write it! --Wtshymanski (talk) 14:44, 21 January 2013 (UTC)

text: The article could really be improved so that it's clearer why this is not a problem with a typical well-designed system!  (e.g. systems with 2 tanks or 1 tank AND a tankless water heater) --Elvey(t•c) 23:42, 24 April 2015 (UTC)

text: == Speaking of Questionable - Thermalux / Solar Energy Labs, Inc. idiocy ==
Wow, what an idiotic system:  Use PV panels to heat water with the electricity generated.  Yes, there's a company actually marketing such an idiotic solution!  (Sure, it'll work, it'll just be very inefficient/expensive/under-powered compared to a proper well-designed system.) 
http://www.offgridquest.com/energy/wind-power/the-best-off-the-grid-water-heater-yet-a  And they managed to get over $6000 committed to their kickstarter project. --Elvey(t•c) 23:42, 24 April 2015 (UTC)

text: Doesn't seem to have attracted any news coverage other than this, so probably not appropriate to include yet.  if it does, I bet it would make an amusing entry in the efficiency tables. --Elvey(t•c) 23:47, 24 April 2015 (UTC)
thread_title:  Questionable Savings 

message: Low pressure polymer water channels made of silicone rubber is mentioned in both second and third type of freeze protection.
This seems to be fixed and replaced with appropriate listings. TacoEditSquad (talk) 02:05, 17 October 2017 (UTC)
thread_title:  Freeze protection list duplicate? 

message: Hello fellow Wikipedians,
I have just added archive links to  on Solar water heating. Please take a moment to review my edit. If necessary, add  after the link to keep me from modifying it. Alternatively, you can add  to keep me off the page altogether. I made the following changes:
*Attempted to fix sourcing for http://www.neaman.org.il/neaman/publications/publication_item.asp?fid=590&parent_fid=490&iid=3639
*Attempted to fix sourcing for http://rredc.nrel.gov/solar/calculators/PVWATTS/version1/
*Attempted to fix sourcing for http://www.aer.gov.au/content/index.phtml/itemId/717887
*Added archive https://web.archive.org/20110927090915/http://www.vlaanderen.be/servlet/Satellite?pagename=Infolijn/View&cid=1090509343446&c=Solution_C&p=1186804409590&context= to http://www.vlaanderen.be/servlet/Satellite?pagename=Infolijn/View&cid=1090509343446&c=Solution_C&p=1186804409590&context=
When you have finished reviewing my changes, please set the checked parameter below to true to let others know.
Cheers.—cyberbot IITalk to my owner:Online 22:10, 6 January 2016 (UTC)
thread_title:  External links modified 

message: Hello fellow Wikipedians,
I have just added archive links to  on Solar water heating. Please take a moment to review my edit. If necessary, add  after the link to keep me from modifying it. Alternatively, you can add  to keep me off the page altogether. I made the following changes:
*Attempted to fix sourcing for http://www.heatingcentral.com/Chromagen_Solar_Water_Heating_Systems
*Added archive https://web.archive.org/20100507211551/http://www.environment.gov.au:80/sustainability/energyefficiency/buildings/homes/index.html to http://www.environment.gov.au/sustainability/energyefficiency/buildings/homes/index.html
*Attempted to fix sourcing for http://www.ren21.net/globalstatusreport/REN21_GSR_2010_full.pdf
*Attempted to fix sourcing for http://www.iea-shc.org/publications/downloads/Solar_Heat_Worldwide-2011.pdf
When you have finished reviewing my changes, please set the checked parameter below to true to let others know.
Cheers.—cyberbot IITalk to my owner:Online 13:31, 9 February 2016 (UTC)
thread_title:  External links modified 

message: Hello fellow Wikipedians,
I have just modified  on Solar water heating. Please take a moment to review my edit. If you have any questions, or need the bot to ignore the links, or the page altogether, please visit this simple FaQ for additional information. I made the following changes:
*Corrected formatting/usage for https://www.environmentcalifornia.org/uploads/at/56/at563bKwmfrtJI6fKl9U_w/Solar-Water-Heating.pdf
*Corrected formatting/usage for http://www.ren21.net/globalstatusreport/g2009.asp
*Corrected formatting/usage for http://lainginc.itt.com/LG-pump-DC-Solar-Pumps.asp
When you have finished reviewing my changes, please set the checked parameter below to true or failed to let others know (documentation at ).
Cheers.—cyberbot IITalk to my owner:Online 11:20, 2 April 2016 (UTC)
thread_title:  External links modified 

message: What is meant by "kW.h"? This way of writing is not SI compliant. Please use a scientific valid notation. Did you mean kW*h? In that case I'm most familiar with seeing it written as "kWh". Since this is mostly accompanied by "/day" I would welcome a more simple and technical number like a peak performance in W. Also the preferred unit for energy should be the J. --BjKa (talk) 13:13, 27 January 2017 (UTC)
replies: text: kWh is the preferred unit in this context. It is normally written "kWh", never "kW.h". Please feel free to remove the dot when you see it. The fact that the unit is so widely used in this context means that even when dividing by another unit of time (day) is still useful to keep kWh/day in most cases for comparisons. --Ita140188 (talk) 06:00, 28 January 2017 (UTC)
thread_title:  "kW.h" 

message: 1. The information about "flat plate collectors" should have a citation about them being used in Florida. 
2. It would be beneficial if in the DIY section the characteristics were more descriptive. Ex: Low maintenance is vague. Low maintenance could mean different things for different people. 
3. Citation needed when discussing the durability of tempered glass in flat plate collectors.
4. In the evacuated tube section, is there any more information that could be added to explain why the vacuum life varies from 5-15 years?
5. When stating the cost benefits, the sentence: "In sunny, warm locations, where freeze protection is not necessary, an ICS (batch type) solar water heater can be cost effective." Sunny and warm are vague. Ex: some people may find 60 degrees to be warm while others say warm is 90 degrees. By being more specific about the exact temperature needed to keep the solar water heater cost-effective. This would erase any confusion. 
 Nathanwcampbell (talk) 19:04, 16 October 2017 (UTC)
thread_title:  Comments about possible changes to consider 

message: Can someone find any new technology as of 2017 to add to this article. I'm sure something new has come out in the last few years that would be pertaining to this. Such as how pricing for installing a system in the US is much lower then it has been.  
Article: https://www.homeadvisor.com/cost/plumbing/install-a-solar-water-heater/ 
TacoEditSquad (talk) 02:08, 17 October 2017 (UTC)
thread_title:  Update 

message: Hello fellow Wikipedians,
I have just modified 3 external links on Solar water heating. Please take a moment to review my edit. If you have any questions, or need the bot to ignore the links, or the page altogether, please visit this simple FaQ for additional information. I made the following changes:
*Added archive https://web.archive.org/web/20110114224043/http://www.sunnovations.com/content/how-sunnovations-system-works to http://www.sunnovations.com/content/how-sunnovations-system-works
*Added archive https://web.archive.org/web/20091104181439/http://www2.vlaanderen.be/economie/energiesparen/doc/folder_zonneboiler.pdf to http://www2.vlaanderen.be/economie/energiesparen/doc/folder_zonneboiler.pdf
*Corrected formatting/usage for http://www.vlaanderen.be/servlet/Satellite?pagename=Infolijn%2FView&cid=1090509343446&c=Solution_C&p=1186804409590&context=
When you have finished reviewing my changes, you may follow the instructions on the template below to fix any issues with the URLs.
Cheers.—InternetArchiveBot (Report bug) 17:37, 22 January 2018 (UTC)
thread_title:  External links modified (January 2018) 

message: In my opinion, the width of a table within the article needs to be increased as the title 'Currency' has been split due to the text space not being wide enough, making the table look unprofessional in my opinion. Xboxsponge15 (talk) 15:24, 29 July 2021 (UTC)
thread_title:  Width of table within the article needs to be increased 

message: Typically green tinted glass is called soda glass, not "coke glass" https://en.wikipedia.org/wiki/Soda%E2%80%93lime_glass 
Optically clear glass needs the addition of some other elements, historically lead, for crown, crystal or leaded glass. Probably what would be important for a Evacuated tube collectors is transparency to infra-red, while absorbance is of import on the inner tube. The IR transmittance of plain old soda glass is awful. https://commons.wikimedia.org/wiki/File:Soda-lime_glass,_typical_transmission_spectrum_(2_mm_thickness).svg
2601:243:1202:D9F0:F854:B822:1A57:ED44 (talk) 02:48, 7 July 2022 (UTC)
thread_title:  "Coke Glass"?  in Evacuated tube collectors section of article