Changes: How solar cookers work

Revision as of 17:34, 16 April 2014

Types

The three most common types of solar cookers are box cookers, curved concentrators (parabolics) and panel cookers. Hundreds — if not thousands — of variations on these basic types exist. Additionally, several large-scale solar cooking systems have been developed to meet the needs of institutions worldwide.

Box cookers

Box cookers cook food at moderate to high temperatures and often accommodate multiple pots. Worldwide, they are the most widespread. There are several hundred thousand in India alone. See Solar box cooker designs.
.

Parabolic cookers

Curved concentrator cookers, or "parabolics," cook fast at high temperatures, but require frequent adjustment and supervision for safe operation. Several hundred thousand exist, mainly in China. They are especially useful for large-scale institutional cooking. See Parabolic solar cooker designs.
.

Panel cookers

Main article: Solar panel cooker designs

Panel cookers incorporate elements of box and curved concentrator cookers. They are simple and relatively inexpensive to buy or produce. Solar Cookers International's "CooKit" is the most widely used combination cooker. See Solar panel cooker designs.

Principles

Most solar cookers work on the basic principle: Sunlight is converted to heat energy, that is retained for cooking.

Fuel: Sunlight

Sunlight is the "fuel." A solar cooker needs an outdoor spot that is sunny for several hours and protected from strong wind, and where food will be safe. Solar cookers don't work at night or on cloudy days, though during the best months for cooking, many foods can be cooked under intermittent clouds or a light haze, as long as food is put out early and there is definitely more sun than not overall. Extra covers or simple foiled boosters can help under marginal skies.

Converting sunlight to heat energy

Dark surfaces get very hot in sunlight, whereas light surfaces don't. Food cooks best in dark, shallow, thin metal pots with dark, tight-fitting lids to hold in heat and moisture.

Retaining heat

Main article: Greenhouse effect

A transparent heat trap around the dark pot lets in the sunlight, and keeps the heat that is produced from escaping. This is a clear, heat-resistant plastic bag or large inverted glass bowl (in panel cookers) or an insulated box with a glass or plastic window (in box cookers). Curved concentrator cookers typically don't require a heat trap.

Capturing extra sunlight energy

One or more shiny surfaces reflect extra sunlight onto the pot, increasing its heat potential. Mirrors, aluminum foil, mylar, mirror-finish metals, chrome sign vinyl, and other shiny materials have all been used successfully for solar cooking, depending on the type of cooker and the environment in which it will be used. See Reflective material.

External links

Parabolic Solar Cookers -Humboldt State University
How Solar Cooking Works - HowStuffWorks
The full text of the book The Expanding World of Solar Box Cooking - Barbara Kerr
Evaluation of Several Original and Commonly Used Solar Cooker Designs - Dane Dormio and Steven Jones
Rating Solar Cookers
French: Evaluation des fours solaires

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 {{GoogleTranslateLinks}}
 ==Types==
 The three most common types of solar cookers are [[box cookers]], curved concentrators ([[Parabolic cookers|parabolics]]) and [[panel cookers]]. Hundreds — if not thousands — of variations on these basic types exist. Additionally, several large-scale solar cooking systems have been developed to meet the needs of institutions worldwide.
@@ Line 9: / Line 7: @@
 ===Box cookers===
-Box cookers cook food at moderate to high temperatures and often accommodate multiple pots. Worldwide, they are the most widespread. There are several hundred million in  alone. India is See [[:Category:Solar box cooker designs|Solar box cooker designs]].<br clear="all" />.
+Box cookers cook food at moderate to high temperatures and often accommodate multiple pots. Worldwide, they are the most widespread. There are several hundred thousand in India alone. See [[:Category:Solar box cooker designs|Solar box cooker designs]].<br clear="all" />.
 [[Image:Parabolic-type.jpg|right|woman with parabolic cooker]]
@@ Line 15: / Line 13: @@
 ===Parabolic cookers===
-Curved concentrator cookers, or "parabolics," cook fast at high temperatures, but require frequent adjustment and supervision for safe operation. Several hundred thousand exist, mainly in China. They are especially useful for large-scale institutional cooking.  See [[:Category:Parabolic solar cooker designs|Parabolic solar cooker designs]].<br clear="all" />.
+Curved concentrator cookers, or "parabolics," cook fast at high temperatures, but require frequent adjustment and supervision for safe operation. Several hundred thousand exist, mainly in China. They are especially useful for large-scale institutional cooking. See [[:Category:Parabolic solar cooker designs|Parabolic solar cooker designs]].<br clear="all" />.
 [[Image:Panel-type.jpg|left|woman with panel cooker]]
@@ Line 21: / Line 19: @@
 ===Panel cookers===
 {{Main|Solar panel cooker designs}}
-Panel cookers incorporate elements of box and curved concentrator cookers. They are simple and relatively inexpensive to buy or produce. Solar Cookers International's "[[CooKit]]" is the most widely used combination cooker. See [[:Category:Solar panel cooker designs|Solar panel cooker designs]]. SHLONGGG<br clear="all" />
+Panel cookers incorporate elements of box and curved concentrator cookers. They are simple and relatively inexpensive to buy or produce. Solar Cookers International's "[[CooKit]]" is the most widely used combination cooker. See [[:Category:Solar panel cooker designs|Solar panel cooker designs]].<br clear="all" />
 ==Principles==
@@ Line 33: / Line 31: @@
 ===Retaining heat===
+{{Main|Greenhouse effect}}
 A transparent heat trap around the dark pot lets in the sunlight, and keeps the heat that is produced from escaping. This is a clear, heat-resistant plastic bag or large inverted glass bowl (in panel cookers) or an insulated box with a glass or plastic window (in box cookers). Curved concentrator cookers typically don't require a heat trap.