How to Choose a Solar Cooker
A Solar Cooker is perfect for supplementing your other cooking methods, saving energy, RV’ing, camping, and your emergency kit!
An All Season Solar Cooker is a great supplement to all other cooking methods. Using the free energy of the sun saves your other energy resources. During the holidays, the All Season Solar Cooker can be used for the turkey while the indoor oven is busy with the rest of the feast.
There are many solar cooker designs to choose from. I teach solar cooking and have prepared the following 4 criteria for use when choosing a solar cooker. These 4 are Collection, Absorption, Retention, Duration (CARD) The cooker that you choose must address each of these attributes
is the means of getting the sunlight into our cooking area. Collection methods range from simple – facing the sun to feel its warmth on your face – to complex – building a mirror array that will concentrate reflected sunlight into one area.
For solar cooking, the simplest cookers just use a pane of glass over a box – and these actually work. But for more reliable and powerful solar cooking, one or more reflectors are used. Reflectors help to magnify and direct the light to the cooking area.
For Collection, the size of the area that receives sunshine is also important. For Collection, the more reflectors (say, 4 vs 1 or none) the better your cooker will work.
occurs when the collected light strikes a non reflective surface. Light absorption occurs best on dark colored, dull, surfaces. Light colored shiny surfaces tend to reflect the light and do not heat up as well – if at all. A pot with a non reflective black surface does a very good job of absorption.
Where absorption occurs is also a factor. Early models of solar ovens had black painted walls and glass doors. The sunlight would enter through the glass, strike the oven walls, be absorbed, and the oven walls would heat. This was great if you wanted hot oven walls but tests have shown this to be a slower cooking method than if the walls are reflective.
Most modern box cookers use a reflective wall inside the cooker. The light enters the oven through the glass, then either strikes the dark pot, where it is absorbed, or is reflected off the shiny oven walls one or more times until it does hit the pot. The absorption of sunlight and conversion to heat occurs directly on the pot that contains the food. This method has been shown to heat food about twice as fast as the black wall method.
So when designing for absorption -plan on using a non-reflective dark colored pot as the target for your collected light.
is the means we use to keep the heat we have created on the pot from escaping.
Panel and/or box cookers will use either a glass oven door, glass bowls, or oven bags to keep the outside air away from the heat.
Duration is the final, and most important consideration
You can achieve all of the above (Collection, Absorption, Retention) but you cannot successfully solar cook unless you maintain these conditions for long enough to cook the food. Duration should be judged in two ways; 1. How long can a particular design collect the sun and; 2. What time of day can a particular design collect the sun. Most solar cookers are designed to collect the sun from 10 a.m. until 2 p.m. This gives a 4 hour cooking opportunity in the middle of the day. The All Season Solar Cooker is designed to collect the sun from sunrise to sunset. This gives a cooking opportunity of 8 to 14 hours, depending on the season. Duration and time of day are both important. But consider this: What if the only time of day that the sun was available was before 10 a.m? of after 2 p.m? In these cases (common on partly cloudy days or in rainy areas) the All Season Solar Cooker could still provide top performance.
Whether for convenience or necessity, your solar cooker must be able to cook at any time of the day. We cannot control the weather. You should choose a solar cooker that will perform whenever the sun is available. Look at the chart below. The ASSC can focus on the sun during all hours of sunlight. Most other designs only focus on the sun during the hours shown in the shaded area. Before or after those hours their performance deteriorates because they cannot capture all of the incoming sun.
Choose wisely. There is only one portable solar cooker that can capture the light from dusk until dawn. The All Season Solar Cooker.