Many people understand the concept of passive solar for heating a home. Fewer realize it can be used in to cook food and sterilize water.

A solar oven is pretty much what it sounds like. It is used to cook food and sterilize water. Most people do not even know they exist, but they are an effective way to cook from both an economic and efficiency point of view.

The basic idea with a solar cooking is to create a box like structure that the sun heats up dramatically. If you have sat in a car in rush hour during the summer, you know the sun can generate a lot of heat. Instead of cooking you in a car, a solar oven focuses on food.

So, how do we cook with it? The box structure is created with dark paneling and then covered with a clear glass or plastic top after pots and food or water has been inserted. The structure is sealed. Much like a car, the sunlight beats through the clear top and heats the interior of the box. As the heat rises, it cooks the items inside. Yes, it produces more than enough heat to do the job. It really is as simple as that.

There are three general types of solar ovens. A solar box works as described in the previous paragraph. A panel oven uses reflective surfaces to focus the sun on a pot to create heat and cook the material inside. A parabolic version is designed to focus the sunlight into the bottom of a concave area upon which sits pots. There are variations of these three forms, but all solar cooking designs are derived from these basic forms.

While cooking with the sun is a fun and efficient, most people will never apply it in their home because of obvious design issues. At a cabin or when camping, however, it is a perfect solution.

Rick Chapo is with SolarCompanies.com, a directory of solar energy companies.