Sustainable design, according to the website ecolife.com, is “the intention to reduce or completely eliminate negative environmental impacts through thoughtful designs.” Often referred to as environmental design, this concept can be applied to various different categories of design. Regardless of the application, however, a sustainable design will try to include certain environmentally-friendly outcomes such as lowering energy and water usage, reducing green house gas emissions, limiting resource consumption by using renewable resources or recycled materials, reducing or eliminating waste products by reusing or recycling them when available, and using non-toxic materials or those that will contribute to human health. A fine example of a sustainable design is the solar cooker.
Throughout the world, people have limited access to cooking fuels. In fact, in developing countries electricity and gas are out of the question when it comes to cooking. Only firewood and charcoal are within reach, and charcoal can sometimes be too expensive to purchase. That only leaves wood, and in developing countries trees are sometimes scarce. It takes a lot of wood to cook an entire meal for a family every day, and what few wood sources there are continue to dwindle. Families often have to walk miles to get firewood, and they often end up spending what little money they have on fuel, leaving less to buy food with. This shortage of cooking fuels results in illness and in a lot of cases death. In fact, 2 million people die every year from bacterial illnesses that could have been prevented by pasteurizing drinking water or food. Fires also release a lot of pollutants into the air. This smoke, filled with particulates, is bad for the environment and for the people who breathe them in. Inhaling smoke and soot often results in both lung and heart disease and an estimated 1.5 million people die from smoke inhalation annually. The use of wood for kitchen fires also creates a local deforestation problem, which destroys animal habitats and other ecosystem functions.
This is where the sustainable design of the solar cooker comes into play. There are two different types of solar cookers: the box cooker and the parabolic cooker. The box cooker uses a shiny metal on the lid to direct sunlight into a dark pot or box, which absorbs the energy and turns it into heat. A glass covering over the box may be used to create a green house effect that allows sunlight to enter but keeps the heat from escaping. This design allows the solar cooker to reach temperatures high enough to pasteurize food and water, which is around 180 degrees F. In fact, the box cooker can reach up to 300 degrees F, and can cook food in a couple of hours.
The parabolic cooker can get even hotter, reaching temperatures up to 400 degrees F. This design is slightly more complicated. It uses curved reflective surfaces to focus a lot of light on a relatively small area. A pot of food sits in the arm of the cooker which suspends it in the middle of the reflective surfaces directly where all the light is concentrated.
The solar cooker uses sunlight, a renewable resource, to heat food or water to the necessary levels of pasteurization. This design greatly improves the health of individuals living in developing countries by killing bacteria in water or food. Also, the cooker eliminates the need for an open flame which means cleaner, safer air free from the particulates that cause lung and heart disease. The solar cooker also reduces firewood usage which protects animal habits and other ecosystem functions. In fact, using a solar cooker for an entire year can eliminate up to 1 ton of firewood. The solar cooker is a great example of a sustainable design that limits resource consumption by using a renewable resource, minimizes impact on the local ecosystem due to the decrease in firewood usage, and uses non-toxic materials that contribute to human health by eliminating the smoke particulates that cause lung and heart disease.