Frequently Asked Questions 22-Apr-2008

Where are solar ovens being used the most?

There are reliable reports that there are over 100,000 cookers in use in both India and China. We are aware of solar cooking projects in most of the countries of the world. See our country by country resources page for information on the use of solar cookers in each country.

How hot do solar ovens get?

Place an oven thermometer in the sunny part of the oven to get a reading similar to what the cooking pot is "feeling". The temperature reached by box cookers and panel cookers depends primarily on the number and size of the reflectors used. A single-reflector box cooker usually tops out at around 150° C (300° F) as the food approaches being done. High temperatures, however, are not needed for cooking. Your oven will cook just fine as long as it gets up to about 90° C (200° F) or so. Higher temperatures cook larger quantities, cook faster, and allow for cooking on marginal days; However, many people prefer to cook at lower temperatures, since then they can leave the food to cook while they go about their business. With a single-reflector box cooker, once the food is cooked, it just stays warm and doesn't scorch. It's good to keep in mind that food containing moisture cannot go much above 100° C (212° F), unless a pressurized cooking vessel is used. The high temperatures you see in cookbooks for conventional ovens are just for convenience and for special effects such as quick browning.

How long does it take to cook a meal?

As a rule of thumb, you can figure that food in a single-reflector box cooker or a panel cooker like the CooKit will take about twice as long as in a conventional oven. However, when the time required to obtain fuelwood and tend the fire are considered, solar ovens usually demand less of the cook’s time. Also, since you food very seldom burns in a box cooker or panel cooker, you don't have to watch the cooker or stir any food as it cooks. You can just put in a few pots with different foods and then come back later in the day and in general the food in each pot will be cooked and kept warm until you take it out. Of course fresh vegetables will definitely overcook and become very soft if left in the cooker too long.

Panel cookers cook smaller portions, usually only in a single pot, but often they cook slightly faster. Some people have reported the need to stir food every once in a while when using this kind of cooker to assure that the food heats evenly.

Cooking with a parabolic cooker is very similar to cooking on one burner of a conventional stove. Since the concentrated sunlight shines directly on the bottom of a pot, the pot heats up and cooks very quickly. The food can burn though, so you have to stir it and watch it carefully.