Use the Sun to Cook your Food

Backgrounder

One way people sometimes describe a really hot day is to say, “It’s so hot, you could fry an egg on the ground.” Well, how about cooking vegetables in a box in the sun? You can do this using the rays from the sun. This is called cooking with solar energy.

Cooking with solar energy is an idea that is getting a lot of attention, especially in countries with hot, sunny weather. That’s because the world is running out of energy sources such as coal, oil and gas. Fuelwood is also hard to find. And people are worried about the damage to the environment and to people’s health when these energy sources are burned. This is not a problem when you cook using solar energy.

How do you do it? Well, you can use something called a solar cooker. There are a few different kinds of solar cookers. Some have pipes, wires, and coils that not only catch the sun’s energy but hold it so you can cook later on at night or on cloudy days. These are called storage cookers. Others cook by using steam heat from water heated by the sun, but they are complicated to make and don’t reach high temperatures. These are called steam cookers.

The simplest and least expensive solar cooker to make or buy is called a solar box cooker. This cooker can be made out of wood or cardboard. It is a box inside a bigger box with lots of insulation between them. You can use feathers, wool, spun fiberglass, or wall sized cardboard pieces covered with foil as insulation. Both boxes are low and wide.

The small inner box is where you put your pots. The inside of the smaller box is covered with shiny aluminum foil. The bottom is painted black or holds a dark metal tray. A sheet of glass covers the two boxes and on top of that there is a lid that can open and close, like a door. The inside of this lid also has shiny foil or a mirror on it. When the lid is open, the foil or mirror catches the sun’s rays and directs them through the glass cover and into the box. The dark bottom inside the box absorbs the heat of the sun, and the shiny sides direct the rays onto the pots. The pots have to be dark to absorb and hold all the heat. The glass plate cover keeps the heat inside.

On a sunny day, the temperature inside the cooker can reach 95 150 degrees Celsius, so the food cooks well. For example, an egg can cook in about 45 minutes, potatoes can cook in 3 4 hours, and large pieces of meat can cook in 5 8 hours. To cook food as fast as possible, let the box get hot for 30 minutes before cooking, and keep moving the box every few hours to face the sun as it changes direction.

There are several reasons to cook using energy from the sun. Cooking with solar energy saves fuelwood and is much less expensive than using fuels like coal, oil and gas. In fact, it’s free! Cooking with solar energy doesn’t create smoke or harmful fumes so it’s safer for whoever is preparing the food. It’s also safer for the environment. What’s more, the food often tastes better and is more nutritious. That’s because you don’t need to use much water – or any water at all – in the pot since the food is cooked slowly and evenly and can’t burn as it can when you cook over a flame.

But there are also disadvantages to cooking with a solar box cooker. You need sunny skies _ you can’t cook on a very cloudy or rainy day. And you can’t cook after dark. Food takes longer to prepare since temperatures generally don’t rise as high as when you cook with a flame. So, even if you do use solar energy, some foods may still have to be cooked, or finished cooking, using heat from wood, coal, oil or gas.

Still, you can save fuel costs, and lose less food from burning when you cook your food using the sun’s energy instead of expensive, scarce energy sources.