Solar cooking pots

The best solar cooking pots are typically made of thin, dark metal with a lid. Pots with polished finishes, which reflect light away from the pot instead of absorbing it should be avoided. Unless you're cooking with a parabolic solar cooker where the light is being focused on the bottom of the pot, it's very important to use dark-colored pots that absorb light and transform it into heat. 
Clear pots will also work, especially with dark colored food ingredients, and pot lids can be either dark or clear. It is important to always cook with the lid in place so that the moisture from the food doesn't escape and fog the plastic bag or other glazing.
The material that the pot is made from will also affect how quickly it heats up and how well it retains the heat. Here are a few points to keep in mind:
*Pots made from thin material heat faster than thicker ones
*Metal pots will heat faster than ceramic or earthenware
*Cast iron is slow to heat initially but will hold heat better than thinner metals. Cast iron should be preheated in the cooker and be used during good solar cooking conditions, as it requires strong sunlight to achieve the best results
*Foil is not generally recommended to wrap food for solar cooking because shiny foil insulates by reflecting sunlight and heat away from the food.
Ideally, the pot/cooker combination should be able to cook a large enough meal to feed the entire family, which can have many members in some cultures. Some introductory projects have not succeeded because the amount of food cooked was not enough to meet the needs of the families who participated. 
==Glass jars==
thumb|300px|Solar cooking with glass jars
Glass jars make good pots either clear or painted out the outside. They may cook slightly better darkened. Also, darkening the outside of food containers will protect some of the B Vitamins. When painting the jars, a strip of masking tape placed from top to bottom before painting can be removed when the paint is dry to leave a tidy strip of clear glass for visual inspection of the inside.
When using jars for cooking, make a hole in the lid of any non-canning jar, such as mayonnaise jars, peanut butter jars, etc., to prevent steam buildup. Dome and ring canning jar lids that are designed for food preservation automatically release excess steam pressure yet are safe only when used on canning strength, food preservation jars. The thickness and strength of non-canning glass jars is not intended to take the strain of steam under pressure and could break explosively unless vented.
==Earthenware pots==
Some low-fired earthenware pots do not initially cook well, although dark colored and hard-fired earthenware pots with glazing work very well. Perhaps the poor performance of some earthenware is due to liquid soaking through and evaporating on the outside, or perhaps it is due to the thickness and porous nature of low-fired clay pot sides. Experimentally, in the efforts to use low-fired, unglazed earthenware, the goal has been to approximate the hard-fired pots by filling the pores and to providing a form of glazing. On a homecraft basis, this has been done by saturating the pot with food-type oil, fat or natural resin which both closes the pores and changes the surface. Oil also will conduct heat rather well and this may be part of what improves cooking in low-fired, earthenware pots following oil treatment. Light colored earthenware needs to be darkened on the outside only, perhaps by rubbing a dark nontoxic dark powder or soot from clean wood into the oil coating. Even so, there may be forms of low fired earthenware that are difficult to use.
==Paints to use==
==Buying pots==
*The classic Granite Ware 3 qt. cook pot with lid, which fits nicely inside of two 3 qt. clear Pyrex bowls, is available on Amazon intermittently. To use the Pyrex bowls as a greenhouse enclosure, avoid the 3 qt. pots with side handles. As of 4/27/23, the 3 qt. Granite Ware covered pot is available on Amazon again. It is advertised as a 3 lb. capacity pot, but matches the dimensions of the classic 3 qt. pot.
*Amazon sells a good pot for solar cooking: https://amazon.com/GSI-Outdoors-Straight-Blue-3-5-Quart/dp/B0002YRHZK
*Another good pot on Amazon: https://www.amazon.com/Granite-Ware-Bean-Pot-4-Quart/dp/B003RY64LK/
*It can be difficult finding smaller covered cook pots in a Graniteware option. A dark colored covered bread pan size has been found from a Hong Kong vendor. Note that this pot has three small holes in the bottom of it apparently to allow steam to escape while baking bread. It is available in quantities of 50+ from Banggood.
::
Banggood_bread_pan,_7-8-15.png|300px|Covered bread pan available in large quantities through Banggood
Stansport_Enamel_4_qt._pot_10-25-11.jpg..jpg|300px|Inspired by traditional Graniteware, the Stansport GSI Enamelware blends old-fashioned charm and functionality into one sturdy package. Plus, three-ply construction maximizes heat distribution for even cooking.
Crockpot-inner-pot.jpg|300px|In the USA, it is very easy to find used crockpots in thrift stores that contain an inner ceramic pot with a glass lid that is perfect for solar cooking.
*Various pots used by hikers are available online from Amazon.com:
**GSI Outdoors Enameled Pot & Lid, 3.5 Quart I Campfire Cookware, Home or Cabin - Blue
**Texsport Black Ice The Scouter 5 pc Hard Anodized Camping Cookware Outdoor Cook Set
*Dull, black cooking pots are also available through a company located in the Czech Republic called Belis, http://www.belis.eu. Their contact page is: http://kontakt.czechtrade.net/belis/en/
==Pot lids==
Pot lids can be homemade by turning the pot upside down on a flattened piece of metal and drawing an outline. Cut the metal about ¼ inch (.6 cm) outside the line. File or sand the sharp edges to dull the cut surfaces and protect the fingers. This may be done simply by rubbing a rock along the cuts. Working regularly around the lid piece with pliers, bend the edge down at the line. Sometimes the fluting looks nice. If necessary, cut from the edge into the line to allow the pieces of edge to overlap. Darken the outside of the lid and heat it for several hours before using it with food. Temporary lids made be made by the same method using a brown paper bag and creasing the paper at the line. These also need to be heated alone for several hours before being used with food. Sometimes small holes are punched in a lid to allow moisture to escape and produce a drier crust on foods such as breads or breadcrumb toppings, cakes and cookies.
Nutritional research in great detail has been done by Professor George Hammons and others at Philander Smith College in Little Rock, Arkansas, USA. After analysis of many different nutrients in food cooked equal times by conventional methods and by solar box cookers using dark pots with lids they concluded that solar cooked foods retained nutrition as well as or better than foods cooked by conventional methods in spite of the longer cooking times required.
===Clear or black cook pot top?===
This has been of point of speculation among cooks using solar panel cookers. Each option has its benefits. Having a clear top means avoiding having to lift the lid, letting valuable heat and moisture escape, when checking on the food. This top probably works better with dishes like soups and stews where the heat is more easily evenly distributed within the pot.
Black tops work better for bread baking. The baking dough receives some additional direct radiation heat gain from the black top, along with the internal heat. This allows baked goods to brown on top.
Teong Tan did side-by-side using various pot/glazing configurations. What was not expected was that the pot with a clear glass lid had outperformed the pot with a metal lid plus oven bag. He states that this could be due to: 
*The metal lid had prevented sunlight from reaching the inside of the pot, where it mattered the most. 
*The downward conduction and convection of heat, from the hot metal lid to the lower part of the pot, were not efficient.
*The amount of sunlight coming in from the top was significant, and this had helped to rapidly raise the temperature of the pot with the clear glass lid.
Steven Andrews came up with a clever alternative. Paint a clear top black with heat-resistant paint, but first mask a wide strip to retain a window to the food inside. Painting the top should provide at least some the benefits of a black metal top.
Note: It should be remembered that using a pane of either float or plate glass runs the risk of breakage while handling or using for a pot top! Tempered glass, like that used in manufactured pot lids, is the better option. Read more about glass properties
===EuroSolarPot===
 
Built by Andrew and Margot, the EuroSolarPot has been tested successfully in France and Poland. The pot is designed for use in solar panel cookers, especially in the Nordic countries. Thanks to some greenhouse effect added by the clear lid, its thermal properties are improved compared to traditional solar pot without a greenhouse enclosure. Click here for more information.
==Tips and tricks==
==Pot risers==
Faustine Odaba wire pot riser, 7-3-14.jpg|Faustine Odaba's wire pot riser made from coat hangers. Photo credit: Faustine Odaba
Pot stand, Matthew Rollins, 12-10-12.jpg|Matthew Rollins has designed a collapsible pot stand to work with a cooking bag.
November 2016: 
SunLife pot carrying framework, 11-18-16.png|SunLife has developed a wood and wire pot carrying device Photo credit: Sunlife
SunLife pot holder with pot, 11-8-16.png|Pot scaffold shown with cook pot Photo credit: Sunlife
SunLife, working in Ghana, has developed a simple wood and wire harness to elevate a cook pot, as well as, provide a way to lift the hot pot either with or without the cooking bag enclosure. The wire frame also maintains an efficient shape for the enclosure.
==Covering reflective pots with a dark cloth==
When cookware with a black surface is not available, it may still be possible to effectively use reflective or colored cookware with your solar cooker. Basically, it involves using a black cloth to cover the cookware after placing it in the cooker. Place the cloth as close to the pot surface as possible to minimize heat loss. Neelaratna Geekiyanage, from Sri Lanka, reports that he has used this technique to cook, pasteurize water, and make copra from scraped coconut to extract high quality coconut oil. He calls it the NG method.
==Some alternative cooking pots==
*Smoked-glass casserole dishes. Pyrex makes a low-cost model available for $5 - $10 in stores in the US. 
*Rough up glass jars with sandpaper and paint these black. Use masking tape to leave one clear strip for viewing. 
*Put shiny pots in a brown paper sack. 
*Paint a shallow cake pan black and fashion a lid from a sheet of black-painted aluminum flashing with its edges folded down. 
*Buy dark baking pans in matched pairs and use one upside-down as a lid for the other. Metal binder clips of the right size—medium to large range, depending on the pan rims—work well for holding them securely together. 
*Finned pots: Arezki Harmim writes in February 2009: "Within the framework of a project of development and popularization of solar cooking in Algerian Sahara, registered in the program of the Unit of research in renewable energies in Saharan medium installed in Adrar (located at the south of Algeria), our team of research proposed the use of a finned cooking vessel with an aim of improving the solar cookers performances. Fins attached to the external surface of the cooking vessel increase the heat transfer surface area. This improves the heat transfer from the internal hot air of the cooker towards the interior of the vessel where the food to be cooked is placed. Indeed, the various experimental tests carried out with the help of a double exposure solar cooker and a finned cooking vessel showed that there is a clear reduction of the cooking time in comparison with the same cooker tested under the same conditions but with an ordinary cooking vessel. The same results were also recorded with a simple box type solar cooker. An example of the finned cooking vessel is shown in the figure."
===Jar-in-jar cooking chamber=== 
Bernhard Müller has created a small cooking chamber and pot combination by inserting a black painted glass jar, with metal top, inside of a slightly larger clear glass jar with a similar top. The two metal tops should be either riveted or screwed together with stainless screws. 
An extremely important feature is to punch a pressure relief hole through both tops. Without it, there is danger of explosion if the lids are sealed too tightly. Care should be taken when cooking with glass jars to avoid accidental breakage. Some jars, like the Mason style used for food canning, are made with heavier glass than is typically used in commercial food sales. While stronger, it does not compare to the strength of Pyrex cookware. The inner jar painted black will become quite hot.
===Blackened coffee can with glass lid===
thumb|250px|none|Here, a blackened coffee can with a glass cover is used as a pot. Under ideal conditions cooking can be done without a glass or plastic enclosure.
===Build your own HotPot bowl===
A few creative solar enthusiasts have been working on ideas to make a HotPot bowl that is inexpensive and easy to use. They incorporate a black pot inside of a larger Pyrex style bowl and lid with an insulated handle. As seen in photos, the addition of a wooden spacer ring has helped provide a seal between pots of slightly different sizes.
Candidates for components include:
*Pyrex® Sculptured 4-3/4-qt Bowl
*Pyrex® 2-qt Casserole w/ Cover <--(only large one sold w/cover) 
*Pyrex® 4-qt Mixing Bowl
*Granite Ware 4 quart beanpot
*Granite Ware 4 Quart Stockpot with Steamer Insert
*Granite Ware 4 Quart Covered Sauce Pot
*Global Sun Oven, Granite Ware, Enamel, 3-quart Pot
==Reports==
*January 2020:  - Atul Sagade
*March 2019: Soot-based coatings for solar cookers - H. Servín-Campuzano, et al
*January 2010: Efficacy of Stainless Steel as Cooking Utensil Material for Solar Cooking - Vandana Kaushik and Ranju Bala
*February 2017: Preliminary work on gasket making for cooking pots - Solar Household Energy
*February 2008: - Teong Tan
*October 2001: An Analysis of Greenhouse Cookpot Design Considerations for Low-Cost Solar Cookers - Florida Solar Energy Center
*Experimenting with stacked pots
==Audio and video==
*July 2023: Using a black or shiny stainless steel cooking pot
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==See also==
*Paint
*Jar lids
*Pressure cookers
*Solar canning
*Glazing
*Other components of a solar cooker
Category:Materials
Category:Research