Talk:Solar cooker

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Above undated message substituted from Template:Dashboard.wikiedu.org assignment by PrimeBOT (talk) 09:45, 17 January 2022 (UTC)

Merge from Solar oven

Solar oven should be a subsection of here. I started to merge a while back, but it seems that I forgot to delete and redirect the other page. D'oh - sorry!. And there's been further edits to Solar oven now, so it needs careful merging. --Singkong2005 03:18, 10 February 2006 (UTC) jhfgujfjkgrgcgedghheat" - isn't it already heat? DavidFarmbrough 17:00 (BST) 12 September 2005

Light would go under the category of "radiant energy". It all depends on how you define "heat".

-User: Nightvid

I'm new to solar cooking technologies but it seems the main content applies only to solar ovens, not all types of solar cookers or parabolic solar cookers. For example. under Operation, paragraph 4, this applies to a solar oven but not a parabolic--correct? If so, I'll try to re-organize and categorize the information as I learn more about this fascinating topic. Lester Woods (talk) 05:57, 11 May 2014 (UTC)

Reasons for unpopularity

I've read that they're not popular because they involve standing in the sun for hours.

Another potential downside is safety, if the food isn't heated to a sufficient temperature.

Something should be added about these points. I don't really know much about this topic though. --Singkong2005 07:43, 28 November 2005 (UTC)

People don't stand in the sun for hours; the solar cooker does. In fact, the food cooks slowly and does not need to be stirred, so this liberates the cook to do other productive work.

Insufficiently cooked food is of course a safety issue no matter how food is cooked. This is not a problem for solar cookers, which can easily reach temperatures necessary to sterilize food or water (over 70 deg. C). Parveson (talk) 20:05, 27 June 2011 (UTC)

my 2¢ 's worth: this is pathetic. Has any of these "change agents" ever asked themselves what is going to happen to those Lesotho women if their husbands come home and supper is not ready? You have got to be able to cook a meal regardless of the weather, and this technology fails to address that basic need. Without some way of storing energy, and using that stored energy whenever needed this is bound to be a total failure. Conclusion: perhaps fun to try out on a camping trip when you have nothing else to do, but totally worthless under any other circumstance. JdH 13:42, 21 March 2006 (UTC)

That's a POV that's not terribly helpful of itself for the article. The point about lack of storage is your best one, but any facts beyond the obvious that solar cookers don't store energy and can only be used when the sun is shining would need research and citation. In areas with consistent sunshine they're probably very effective especially if a backup method is available. A large enough collector would probably be useful even in some overcast situations. Anyway, research is the answer and with that expanded information on their lack of popularity and the factors affecting that would be useful. - Taxman ^Talk 15:29, 21 March 2006 (UTC)

I put in a reference to a review; did you read that? But my negative reaction was really triggered by that term "change agents": If the technology doesn't sell itself by proving itself to be useful then it is counter productive to try to "convince" people. Rather than "convincing" you need to listen to what people's needs are, and see how you can address those needs. JdH 16:19, 21 March 2006 (UTC)

I hadn't sorry. But it's not the highest quality review and not exaclty the highest quality reference of course. Now that I'm on it I'll see what I can dig up. But the change agents stuff is unsourced and should be modified too so you're right on that. But don't forget even good technology doesn't sell itself. Refrigerators had to be sold too, door to door in fact; there was significant resistance to those too. Before things hit critical mass natural resistance to change and lack of information on choices prevents the change. - Taxman ^Talk 16:27, 21 March 2006 (UTC)

A magazine article covering attempts to get these adopted in India? maybe in the 1960's said that a cultural reason for not adopting these in some communities was that "food cooked outside the home" was an invitation to neighbors and others to join in the feast.

If your already a poor family, having to give away your meager ration just because your using a solar cooker outside is going to be a non starter. Bobpage (talk) 03:50, 16 April 2012 (UTC)

windy day

what would u do if it were a wndy day and u wanted to use the solar cooker that u made?

You would use the firewood that you saved on the days when you were able to cook with the sun. —The preceding unsigned comment was added by 24.19.27.192 (talk) 18:10, 4 April 2007 (UTC).

Mild to moderate winds won't make too much difference with a box style cooker, and even a panel cooker can perform fairly well in some winds, though the panels do catch the wind and may try take off if not secured. A box style cooker also gives more margins as to overcast. A completely clear sky is not necessary to successfully cooking in a box cooker. Since a well-made box cooker holds the heat as well as collecting it, short periods of shade from an occasional cloud going over will not disrupt the cooking process, though it might lengthen it slightly.--SharonID 06:46, 2 May 2007 (UTC)

Article needs better formatting

somebody practically deleted the whole page, and i got it back up, but there are still some problems. thanks Bobguy89 20:06, 10 May 2007 (UTC)

Working on it. I think the basic structure makes more sense now. Blue Rhino 03:30, 20 July 2007 (UTC)

HotPot

I did some looking around about the HotPot, and it doesn't seem like it's worth devoting a whole section to. Maybe we should include it in a list of humanitarian organizations that are solar-cooker related. But I don't think it has enough significance to discuss at length in this article. Blue Rhino 03:29, 20 July 2007 (UTC)

I've also looked at it, and I'm not convinced that it is a solar cooker at all. It seems to be a replacement for using an oven bag and a normal pot in panel cookers (like the CooKit). Does anyone know more about this? Can the Hot Pot be used by itself as a solar cooker? WhatamIdoing (talk) 18:20, 4 March 2008 (UTC)

I don't know where you are looking, but the HotPot is a very effective, durable and widely-used solar cooker. It was cleverly designed by engineers to provide thermal gain via the greenhouse effect, as well as by reflection from polished aluminum panels. The panel, by the way, is designed to fold flat for easy packing. I replaced the image with a clearer one. For more details see the site of Solar Household Energy.Parveson (talk) 19:53, 27 June 2011 (UTC)

Solar kettles

The image does not go with this text. The image shows a tea kettle heated by a parabolic solar cooker. The text describes evacuated tube solar collectors, which is an entirely different technology that is generally used for solar water heating. The paragraph refers to a specific device created by one individual and ambiguously named. Parveson (talk) 00:01, 28 June 2011 (UTC)

More solar cooker types needed

See solar cooker models and all solar cooker designs list for a list of all solar cookers on Solarcooking wikia (still many of them not imbedded into article. DIY-solarcooker construction and extra models may also be derived from this site

Finally, look into this site for even more solar cookers KVDP (talk) 08:35, 31 January 2008 (UTC)

There are hundreds of inventions related to solar cooking that have been devised by individuals; many of them are catalogued in the above-mentioned places. Those are the appropriate places for them. This page should be used for organizing these devices into various categories based on their design, size, appropriate foods, cooking power etc. This is what is needed. Parveson (talk) 00:11, 28 June 2011 (UTC)

Environmental technology template

I'd like to replace the Environmental technology template with one that matches the standard navbox style, i.e. horizontal instead of vertical, collapsing and typically placed at the bottom of article pages. I've done a mock up of what this would look like at {{User:Jwanders/ET}}. Figured this was a big enough change that I should post before going ahead with it. Please discuss here--jwanders^Talk 22:03, 17 February 2008 (UTC)

External links

Just wanted to give this page's regular editors a heads-up that it's time for a review of the External Links section. You may want to familiarize yourself with the official policy on external links, and I encourage everyone to remove links that do not seem to meet these guidelines. In general, however, the goal is to have:

• only links which provide "encyclopedic" information about solar cookers (=something useful to student writing an essay for school)
• no links that are primarily trying to sell things
• no links that are (or should be) used as references higher up in the article
• the fewest number of links possible (so that only the "best" links are included)

The goal is not to list all possible organizations, manufacturers, and so forth: Wikipedia is not an advertising opportunity. I've put this article on my list for a day or two from now, but anyone who feels like it can get started now. Thanks, WhatamIdoing (talk) 21:30, 3 March 2008 (UTC)

I've just done a quick organization-of-links on the External links section. If you think any are miscategorized, please make appropriate changes. I've also removed a dead link and a duplicate link, and repaired another so that it works again. WhatamIdoing (talk) 19:20, 4 March 2008 (UTC)

few facts

"The tripod hybrid grill is revolutionary in that many, if not all, of the parts required to build them can be scavenged from commonly thrown away items."

thats true of nearly all cooker types. hardly revolutionary

"Solar ovens can be used to prepare anything that can be made in a conventional oven or stove "

the temperature's much too low for frying or roasting.

Reasons for unpopularity were mentioned further up: ths is quite an important aspect of solar cookers imho, and currently missing from the article. Tabby (talk) 03:27, 22 June 2008 (UTC)

Most (home-sized) solar ovens are sufficiently hot for roasting, which can be done at a mere 200 degrees F. Rather, the problem is that solar ovens are not dry heat, and so your "roasts" are instead braised or stewed.

For frying, a small amount of frying can be done: heat a heavy (e.g., cast iron) pan and oil to frying temperature (300+ F) in a decent box cooker, remove it from the cooker, and fry your egg. It takes about three minutes to fry an egg, and a heavy pan won't cool down that quickly.

As for the tripod grill: that language is certainly WP:PEACOCKing if nothing else, and should be re-phrased to be a neutral, detached, encyclopedic statement. Would you like to do that? WhatamIdoing (talk) 06:40, 22 June 2008 (UTC)

Indian low-cost cookers

Include following line to the article (reformulate text):

Gandhian activist M K Ghosh can rightly be called the father of the solar cooker which is being promoted in India today. Ghosh's cooker was a double-walled wooden box with a double-layered glass window and an adjustable mirror. Solar radiation, which entered directly through a glass window and through reflection from the mirror, got absorbed by the black inner surface. Temperatures reached up to 90 C. Mohan Parikh of the Agricultural Tools Research Centre (ATRC) made improvements on M K Ghosh's cooker in 1976 and came up with an inexpensive model which rural people could afford. It was made of wood and used paddy husk for insulation.

Materials like hardboard, cement sheets and boxwood were also employed by M M Hoda of the Appropriate Technology Development Association (ATDA) in Lucknow to build his janata cooker. ATDA came up with a still cheaper kisan cooker, insulated with paddy husk and plastered with dung. Costs were thus cut down by 50 per cent. Hoda incorporated a 200-watt electric light bulb into the existing design and demonstrated how the cooker could be used even at night to cook rice, dal and vegetables within two hours. Nearly 50 per cent of the cookers sold by ATDA have had these bulb attachments.

The first parabolic solar cooker was developed in the early 1950s by M L Ghai at the National Physical Laboratory (NPL) in Delhi.

See http://www.indiaenvironmentportal.org.in/node/5799 —Preceding unsigned comment added by 81.245.168.190 (talk) 09:29, 12 February 2009 (UTC)

This is interesting information. Do you realize that most of this would be re-written without names? It might look something like this:

An early model of solar cooker in India was a double-walled wooden box with a double-layered glass window and an adjustable mirror. Temperatures reached up to 90 C. Improvements in the 1970s reduced the price by using paddy husk for insulation. Lower cost materials such as hardboard, cement sheets and boxwood were employed later; with the use of paddy husk for insulation and dung for plaster, costs were eventually cut in half. Many solar cookers in India are sold with an attachment for a 200-watt electric light bulb, so that the oven can be used at night.

Wikipedia is not trying to make individuals famous. WhatamIdoing (talk) 06:04, 23 March 2009 (UTC)

this solar power is tremindes —Preceding unsigned comment added by 137.164.228.77 (talk) 16:40, 21 April 2010 (UTC)

This is a cultural matter. In the "west", we tend to avoid putting people's names in articles like this. But in other parts of the world, notably India, it is regarded as highly disrespectful, bordering on theft of intellectual property, to describe someone's work without giving him credit for it and mentioning other notable things he has done. Wikipedia is supposed to be international, so it must make some sort of compromise over this. DOwenWilliams (talk) 20:34, 20 August 2011 (UTC)

References

Illusion of precision required for parabolic cookers

The math shown for design is way too precise.

All solar cookers use the sun. The sun is not a point source of light. It is roughly half a degree wide.

All solar cookers use a pot, kettle, container of some sort. Say two liters or four quarts in size. The target container is unlikely to be a point or even to be a half degree in size. Even a target pipe in a trough style collector is unlikely to be just 1/2 a degree wide.

The article should explain that a practical design can be very sloppy in terms of the math and still every bit as practical.Bobpage (talk) 04:22, 16 April 2012 (UTC)

Approximately, a litre is the same as a quart. It's a bit bigger than a U.S. quart, and smaller than an Imperial quart. Suggesting that two litres equal four quarts demonstrates a great tolerance for errors!

Yes. It's true that solar cookers can often work well if they are only roughly constructed. But guesswork has limitations. Some people's guesses are very poor. Calculating things accurately is easy to do with a pocket calculator, and eliminates poor guesswork. It may be impractical to construct the cooker to the exact calculated dimensions, but attempting to do so will make sure that it is close enough to work.

DOwenWilliams (talk) 04:51, 16 April 2012 (UTC)

Much food just needs heating

Quite a lot of food does not require cooking, as much as it benefits from heating. Also recipes, to make use of convenient tests such as boiling point, are often quite precise and specific, when anything loosely approximating the process might also work. Manufacturers recommend cooking of many things -- often just for their own protection. Fresh, carefully stored hot dogs can be eaten out of the package. Obviously very fresh fish from unpolluted sources can be eaten raw, as in sashimi. Some people would say that tea and coffee should not be made with boiled water.

The nub of the comment is that solar cookers might be a lot more popular were it not that so much of our information about food depends on conventional cookers and conventional recipes. There's been good effort in the article to discuss, for example, cooking vegetables, but it might be of benefit to characterize broadly the scope of kitchen cooking that is primarily solar. Is it possible to cook that way, primarily?

Also, there's the issue of low solar power on overcast days, winter, and near the poles. This would seem simply to require a larger reflector, it's not an inherent problem with solar cooking, as such. 76.102.1.129 (talk) 03:18, 30 December 2013 (UTC)

No, a larger mirror won't help you on an overcast day. Parabolic mirrors conserve flux, as measured in watt per square metre per steradian. They convert highly directional low intensity radiation into low directional high intensity radiation. It doesn't matter at which point of an overcast sky you point the mirror, as long as the light source is isotropic it won't give you any increase in intensity (as measured in watt per square metre). From a thermodynamic instead of optical point of view, a working solar concentrator under overcast skies would be a violation of the Second Law.

Winter or high latitude doesn't matter in se, but when the sun is low in the sky, its light has to travel further though the troposphere, greatly increasing the chance it hits a cloud before reaching the mirror. From the point of view of the solar cooker the sky is usually overcast when the sun is low, even when lots of blue sky is still visible around the zenith. So solar cookers are not particularly practical outside the desert and steppe zones, which isn't that bad, as those are exactly the regions where conserving firewood is important. PiusImpavidus (talk) 14:30, 4 May 2015 (UTC)

Nice theory but I don't buy it. If an overcast sky radiates more heat than the ground, e.g. clean snow radiating very little, then an object under an overcast sky will collect more heat from above than below.

If you now put a small perfectly reflecting flat mirror under the object it will collect a little additional heat from below. As you keep enlarging the flat mirror the amount of heat from below will keep increasing.

Granted the increase asymptotes to a factor of at most 2, but you weren't allowing anything let alone a factor of two.

Not enough to fry an ant on an overcast day though, surely a disappointment to future generations of young sadists. Vaughan Pratt (talk) 07:22, 16 June 2015 (UTC)

Edit request

In the "Vacuum tube technology" sub-section, change the period after "light a fire" (fourth line) to a semi-colon and add "these vacuum tube solar cookers can cook a meal in as little as 20 minutes. Other vacuum tube solar cookers, such as the GoSun Fusion, include an electric heat element that also allows them to cook at night." This is to provide additional info on the capabilities of vacuum tube solar cookers.

Supporting sources (refs 3 and 4) are provided in the collapsed section below.

Extended content

Vacuum tube technology Evacuated tube solar cookers are essentially a vacuum sealed between two layers of glass. The vacuum allows the tube to act both as a "super" greenhouse and an insulator. The central cooking tube is made from borosilicate glass, which is resistant to thermal shock, and has a vacuum beneath the surface to insulate the interior. The inside of the tube is lined with copper, stainless steel, and aluminum nitrile to better absorb and conduct heat from the sun's rays. Some vacuum tube solar cookers such as the GoSun stove incorporate lightweight designs which allow great portability. Portable vacuum tube cookers such as the GoSun allow users to cook freshly caught fish on the beach without needing to light a fire; these vacuum tube solar cookers can cook a meal in as little as 20 minutes. Other vacuum tube solar cookers, such as the GoSun Fusion, include an electric heat element that also allows them to cook at night.

References

Davykamanzi → talk • contribs • alter ego 21:20, 31 August 2020 (UTC)

Not done, promotional namedrop. – Thjarkur (talk) 15:59, 6 September 2020 (UTC)

@Þjarkur: In the same vein as my request at Talk:Solar-powered refrigerator, in the "Vacuum tube technology" sub-section, change the period after "light a fire" (fourth line) to a semi-colon and add "these vacuum tube solar cookers can cook a meal in as little as 20 minutes. Other vacuum tube solar cookers include an electric heat element that also allows them to cook at night" (refs provided in the collapsible section below). Note that any mentions of GoSun or any other company has been excluded.

Extended content

Vacuum tube technology Evacuated tube solar cookers are essentially a vacuum sealed between two layers of glass. The vacuum allows the tube to act both as a "super" greenhouse and an insulator. The central cooking tube is made from borosilicate glass, which is resistant to thermal shock, and has a vacuum beneath the surface to insulate the interior. The inside of the tube is lined with copper, stainless steel, and aluminum nitrile to better absorb and conduct heat from the sun's rays. Some vacuum tube solar cookers such as the GoSun stove incorporate lightweight designs which allow great portability. Portable vacuum tube cookers allow users to cook freshly caught fish on the beach without needing to light a fire; these vacuum tube solar cookers can cook a meal in as little as 20 minutes. Other vacuum tube solar cookers include an electric heat element that also allows them to cook at night.

References

Davykamanzi → talk • contribs • alter ego 20:31, 7 September 2020 (UTC)

Related to the other response, I don't see this as an improvement to the article. I think readers are aware that they can cook fish on their cooker and that meals usually take around 20 minutes to cook. Electric heat elements verge a bit away from the subject of solar cookers. – Thjarkur (talk) 21:43, 7 September 2020 (UTC)