SAIIER 2014:Learning about biochar and biogas
Auroville Nature Camp
|Learning about biochar and biogas|
biomass gasification and use of biochar as a soil amendment
The project was carried out in two schools, Transition and Udavi. The classes were chosen based on discussions with the science teachers in both schools. In Transition, the 8th grade was chosen, with two batches of 12 students each (total 24) and in Udavi, the 10th grade was chosen with 16 students.
Four lessons were done in each school: two lectures, and two practicals. The sequence was changed slightly based on the discussions with the teachers. So I began with lectures. The lectures were focused on explaining the significance of biochar and biomass management for sustainability in terms of interconnections with various aspects of environmental conservation such as water quality, air quality, soil productivity, and global warming as well as the basic principles of conservation. Two movies on biochar (Terra Preta) and biomass energy were shared with the teachers, who showed them to the students in additional lessons. In Udavi school, students were asked to write a small report after each lesson, and in both schools, students were given a quiz, so that we could see how far the students understood the concepts (extracts from the reports and quizzes given below).
The first practical was a field visit to two charcoal kilns and field trials (Discipline Farm and Adam retort). The second practical was conducted in school, which included demonstrations of the gasifier stoves and charcoal cooker to show how gasification works as well as to give hands-on experience to the students of using the stoves and observing the process of making biochar. After the lectures, many students showed interest in using the small kiln as well. So this was included in the last practical (photos from the practicals shown below).
A few students also showed interest in continuing the experiments; so small amounts of biochar were given to the interested students to experiment with at home. Unfortunately, we were not able to provide a safe learning space for continuing the experiments with stoves and kilns. Also, since these lectures and experiments were done in January and February, the teachers felt that there was not enough time to conduct the farming and composting experiments this year. However, teachers from both schools have shown interest in repeating this unit next year and starting early, so that the students have enough time for the crop growth experiments.
Extracts from student reports and quizzes
“I learned about how charcoal absorbs and releases energy and nutrients for the Earth. It is like “Wheatabisc”. A slow energy release breakfast. I really enjoyed the movie. But I still think there’s more to know. In physics chemistry we are learning about all the scientific explanations about carbon and its properties and now I see why and how it gets the name Life chemistry” - Udavi student
“Cookstoves are important because they can provide flame and heat to cook as well as making biochar. They also use most of the side products of burning and are quite easy to use. They can really help the environment if they are used by many people instead of gas stoves” - Transition student
“I now have idea to make charcoal and mix with compost and put to my garden. I have informed some farmers to use charcoal and they said that it is expensive, but I said if we make it ourselves, we can make it with less amount. They said I will try to do what you said.” - Udavi student
“This time during our charcoal class we learnt how they made charcoal and the different procedures. I was very interested in the kilns and their productivity levels. I would really like to take the time to watch and learn how to use the kiln.” - Udavi student
“Everything in its place: Everything is necessary in the correct quantities. An example would be carbon that is currently creating a negative effect because there is too much of it in the atmosphere. Carbon greatly helps the growth of plants when it remains in the ground but contributes to global warming in the atmosphere. So we should not think there is too much carbon, it simply happens to be in the wrong place” - Transition student
“When I heard of the word charcoal, I thought that the charcoal is the black piece, which remains after burning woods. But after seeing the different ways of making charcoal, I got an idea of what charcoal is. And I also learnt the logic of “everything in its place”. That really made a lot of sense to me” - Udavi student
“It (biochar) stops the soil from releasing lots of carbon into the air, helps the soil to be more fertile so crops grow better. We have think in a circle, and make sure that we know where we get products from and what happens when we throw them away. We should try to make sure that things we do and the things we use aren’t harming the environment” - Transition student