Written by “Jack” Chao H.
Scientists predict that natural resources such as fossil fuel, gas and rare minerals will be exhausted in 400 years. One of the major goals of CIRENAS is to create sustainable systems to support our daily life and find solutions to the lack of non-renewable resources. Nowadays, we have some mature techniques of renewable energy but they are not being used extensively. Solar, wind, hydro and geothermal are common renewable energy sources and all of them are presently being utilized in Costa Rica.
Our campus is located on the Nicoya Peninsula of Costa Rica, which is on average 32 degrees Celsius to 38 degrees Celsius during the day. Under this beneficial condition of high temperatures we decided to use solar energy equipment to cook our food. Finally, we found out that the liquefied gas we use for cooking everyday is $16 per tank and that we were using 1 tank a week. Calculating three months of this program we consume 12 tanks of gas, or $192 or approximately 96 gallons. Not only it is expensive but also against our goal to build a sustainable system of living life.
On Feb 28th, Francis Vanek from Ithaca New York, who is a professor of Cornell University came down to our community and taught us how to make a solar oven. Francis taught us how to calculate perfect angles for the sun’s reflection for each hour of the day. We tried to use as much as we can of local materials instead of imported goods from foreign countries. Our solar oven is mostly made by wood and metal. We measured all the lengths, widths and weights of our base frames and wooden board and used sandpaper to sand the surface of all those prepared wood parts. We filled the walls with coconut husks, which are a common material found in Costa Rica for the insulation. We stuck the smooth zinc coated sheet metal to reflect the sun light into our oven to heat it up. On the top of the oven we used two pieces of glass, not only to retain the heat but also we can see through them and are able to look at the process of our food cooking inside, because they are transparent.
We had been working on the solar oven project for two weeks with our group and local schools students and all of us were curious and hopeful of how are solar ovens going to work well. After finishing up our first two solar ovens, we were impatient to test them. First we put two eggs in a pan and adjusted the oven to face the sun. In about ten minuets, two cooked and eggs came out perfect. It tasted super good because the solar oven raised the temperature little by little, so eggs had not been scorched and had cooked evenly. Each day, we were making some deserts such as cookies, pies etc. Then, we put them into solar ovens in the early morning so that later in the day we could enjoy these delicious foods at dinners.
We really had a good time working together with everybody. What I learned from this project is about how to learn from nature and protect it. We are standing on the top of the food chain but we also can choose to be a producer to give our efforts back to nature. There are seven billion people in this world, if everybody can take one small step, our environment will become better and better.