Eight months after the opening of the SolarVillage-test field in Tamera a new module is built, which will enable a self-sufficient energy supply for a village year round: a biogas plant. It will run the kitchen in the winter rainy season in the months where direct solar power often is not sufficient. For the first time, this well-established system in Nepal and China will be modified to European conditions. It is a research and a training project of the Global Campus: Participants from South America, including representatives of the peace community San José de Apartadó in Colombia and of indigenous peoples are expected tp participate. There, in the rainforest biogas could be an important alternative for the local energy autonomy as the irridiation of the sun is limited.
The experimental power plant has been constructed by Michael Stang and Martin Funk. Martin, one of the engineers: "I'm a fan of low-tech solutions that can be realized in simple workshops. Also residents of poorer countries can understand and build it themselves and by this create their energy autonomy. And who knows, maybe soon in Europe we will rely on the advantages of simple technologies."
The solar systems of the test field meet the energy needs of the kitchen in the summer months. In the search for a complement to the winter months with insufficient sunshine, the SolarVillage team came to biogas. Biogas can be produced from any form of biomass through anaerobic processes, i.e., in an airtight biogas plant. It consists of methane (CH4), carbon dioxide (CO2), hydrogenperoxide and traces of other gases.
In Tamera during the year, various forms of biomass are created: food waste, tree and shrub cutting, horse manure and human feces in the compost toilets. Using this potential for the environment, for energy, is the objective of the biogas plant.
Enviromentalists in Europe tend to be critical of biogas as an energy alternative: In Europe almost exclusively large plants are in use, the biomass is produced in large monocultures, fertilized accordingly and uses space away which could be used for food production. When all factors are included, the effectiveness is rather questionable.
In Nepal and China it is quite different: There, many villages have biogas plants or "digesters" which produce, with simple technology, biogas that is used for cooking and even for the busses.
This is the system that the SolarVillage team is implementing in June during a training seminar. Since this will be also used as a research facility for the adaptation to European conditions, some additional elements are to be installed.
A Nepalese biogas consists of an underground pit, which is covered with a brick or concrete dome. Here, the organic material is microbially fermented to methane. The rising gas gathers in the dome and then is directed either to a store or via cables directly into the kitchen for cooking.
At the plant, some toilets are installed. Additionally there is a funnel in which food waste or other organic material can be mixed with water and then supplied to the fermentation tank.
The fermented material is fed into an evaporation tank, dried and can be introduced as a high quality fertilizer in the landscape garden. (Without human excrement, use in the orchard would be possible.)
The research facility should also show how the system operates under European conditions. Therefore, in comparison to the original version from Nepal some additional elements are added. The system is heated by solar collectors. Heating pipes and thermal sensors control the temperature precisely. Even a manual agitator is installed in the fermentation tank, which is not present in the Nepalese plants. It is a safety feature to prevent the occurrence of floating layers. A program will also test the direct use of the fermented humid mass for the irrigation and fertilization of fruit trees.
The plant will offer the opportunity to conduct experiments for the fermentation of various materials, which are generally regarded as unsuitable for biogas plants, such as tree and shrub cutting, obtained in large quantities of Tamera.
As autonomy for a peace village is not only dependant on energy question, the second part of the education will be about community building and conflict resolution.
As the participants are often unable to pay for the travel expenses and classes, any donations are welcome.
Please write to: solarvillage@tamera.org
