A solar oven, sometimes referred to as a solar cooker, is a device that allows you to cook food using the sun's energy as fuel. The most common kinds of solar cookers are curved concentrators (also known as parabolic cookers,) panel cookers, and box cookers. Curved concentrators resemble a mirrored satellite dish. They cook at high temperatures, but require frequent adjustment. Panel cookers combine elements of a curved concentrator and a box cooker.
Homemade solar oven designs range from simple, inexpensive cookers that can be made in an hour, to complex systems that can cook at higher temperatures. One uncomplicated panel cooker design uses an automobile sunshade reflector to concentrate sunlight onto a black surface to cook food. Solar box cookers reflect and collect heat into a box, in which multiple cooking pots can be placed. This article will show you how to make a simple box cooker using common household supplies.
Is it really possible to cook with the sun? Yes! With a few simple adjustments, almost any recipe can be cooked in a solar oven. This article will show you how to make, use and enjoy a solar oven. Included is a solar oven construction plan that is easy to follow and can be constructed from simple materials on one day. I will provide tips along the way to make the process even easier and your oven more efficient. Solar cooking recipes links are included so that you can begin to enjoy the benefits of using a solar oven right away.
Photo credit: Self-Sufficient-Blog.com
First, heat must be collected. Sunlight is the fuel. In order to use sunlight, it must be collected and converted to heat energy. Dark surfaces get very hot in sunlight, so it is recommended to cook in a black, shallow pot with a tight lid to hold in the heat and moisture.
Next, heat must be retained. A transparent heat trap around the dark pot lets in sunlight and keeps in the heat. Types of wraps include clear, heat-resistant oven bags, inverted glass bowls, clear plastic or window glass.
Finally, increase and concentrate the heat. Shiny surfaces can reflect more sunlight onto the pot, increasing the potential for heat.
Photo credit: PracticallyOffTheGrid.com
Here are some of the recipes and tips that I share in my classes. Print as a two-sided document, assemble the pages and staple in the middle to create a small solar cookbook.
There is a rise in interest in solar cooking, with good reason! Solar cooking has many benefits.
- Solar cooking saves fuel and is environmentally benign. It uses the power of the sun, which is a free, renewable resource.
- Solar cooking saves money spent on utility bills for fuel. And your kitchen stays cool on hot days!
- Slow cooking in a solar oven retains moisture, flavor and vital nutrients. Scientific evidence shows that foods cooked at a moderate temperature may be healthier.
- Solar cooking is easy. Solar ovens do not burn foods, so no periodic or constant stirring is necessary. Foods cook virtually unattended.
- Pots used to cook in a solar oven are easy to clean, with no burned on spots or sticky cooking oil film caused by high temperature cooking.
- There is no risk of smoke, fire, or carcinogenic burning of food. There is very little danger to children.
- Solar cooking is versatile, portable and wonderful for camping.
- Solar ovens do not depend upon electrical or gas power. Solar cooking is a skill everyone should know for emergency food cooking, as well as water and milk pasteurization.
What Can I Cook in a Solar Oven?
Almost anything! Fruits, vegetables, meats, grains, even bread and desserts! A solar oven functions like a slow cooker, so it is able to cook roasts, casseroles, soups and other items that would normally be prepared in a crock pot. It can dehydrate foods, such as dried fruits, herbs and meats. It can also function like a conventional oven, giving you the ability to bake breads, cakes and cookies. Rice, beans and even pasta can be made in a solar oven, though they take a longer to cook than they would on the stove top.
Solar cookers do not get hot enough to boil liquids, stir-fry, sear meats or to bake pancakes and other flat breads. However, water can be pre-heated in a solar oven so that it boils quickly on the stove-top, and foods such as pasta and rice that are generally cooked by boiling can be prepared in a solar oven at a lower temperature. Meats can be seared or browned on the stove, and finished cooking in a solar oven with a tender, juicy result.
Photo credit: KnowledgePublications.com
Any time that the length of your shadow on the ground is shorter than your height, the sun is high enough to cook. The sun is most intense between the hours of 10:00 am and 2:00 pm, which are prime solar cooking hours. However, a solar oven can be placed in the sun early in the morning, in order to begin heating up, and a well-insulated, hot oven will cook for an hour or two later than 2:00 in the afternoon.
The sun's angle as it moves across the sky can effect solar cooker temperatures. The angle of the sun is highest during summer months, but in many places, solar cooking can be done during most of the year.
In general, you will need to add one hour to your conventional cooking time. Approximate cooking lengths for different types of food can be found in the following PDF file (you will need Adobe Acrobat to open the link:) How to Make, Use and Enjoy Solar Cookers.
The cooking times provided in the publication are approximate because solar cooking is not as uniform as conventional cooking. Many factors can affect the speed of solar cooking, including the following:
- Time of year: cook times are longer in the winter than they are in the spring and fall, and cook times are shortest during the summer.
- Amount of sun: Cloudy days require longer cook times than sunny days.
- Amount of wind: Wind dissipates heat, which causes the oven to cool and require a longer cook time.
- Type of pot: a large pot will take longer to heat than a small pot. An insulated pot also takes longer to heat up than a pot made of thinner material. Black pots heat up faster and hotter than light-colored or shiny, reflective pots.
- Amount of food: Larger amounts of food take longer to heat up and cook than smaller amounts of food.
- Amount of water: Water takes a long time to heat in a solar oven. A lot of water means a longer cooking time. In general, solar cooking requires less water than stove-top cooking.
- Orientation of the Cooker: A cooker that is moved periodically throughout the day to follow the sun will cook faster than a cooker that is not facing directly directly towards the sun.
Under normal conditions, a solar oven will cook at a temperature of 180º-250º Fahrenheit. Foods cook well at temperatures between 180-195ºF. The temperatures inside a simple solar cooker are hot enough to fully cook meals, but not so hot as to burn or dry out food, or to damage healthful nutrients.
Warning: food allowed to cool to temperatures between 50 and 125ºF for four hours or longer should be discarded as it may be harmful if ingested, causing bacterial food poisoning. If in doubt, throw it out.
Photo credit: SolarCooking.Wikia.com
Check out my article Solar Pot Roast, French Bread and Cinnamon Baked Apples to find out how to make an entire meal in a solar cooker.
Here are some more links to places that I like to visit on the web.
Solar Cookers International
Solar Cookers International (SCI): Harnessing the sun to benefit people and the environment.
How to Make, Use and Enjoy a Solar Cooker
What exactly is a solar cooker? It is a device that allows you to cook food using the sun's energy as fuel. Is it really possible to cook with the sun? Yes, and this booklet will show you how. It will walk you through the process of building a simple oven.
Recipes for Solar Ovens and Solar Cookers | Solar Oven Society
The following recipes have been sent in by avid solar cookers who want to share the good things they have discovered when solar cooking.
Daily Solar Cooking Recipe
Delicious recipes posted daily by the Sun Oven company.
Solar Oven Recipes
Learn to cook eggs and potatoes in a solar oven. More recipes, as well.
SOLAR COOKING RECIPES
Solar oven cooking is easy. Exact timing is not important. The gentle, solar heat is what gives food the enhanced flavor that is always present in this method of cooking. You will become an expert in no time at all. Just experiment a little!
Solar Oven Recipes | Preparedness Advice Blog
You can make great meals with your solar oven.
Here is a PDF instruction manual that you can download and use. Drawings are property of SolarCooking.org. Text and photos are property of The Micro Farm Project.
A few items that you will need:
1. Black cookware with lids
2. Thermometers to measure the oven temperature and the temperature of your food
3. A rack to lift cookware off of the bottom of the oven, for more even and efficient cooking
Commercial Solar Cookers
If you don't want to make your own solar oven or you want one that is more sturdy, there are several options available online. These ovens are portable, cook at higher temperatures than homemade ovens, and have good reviews by users.