The Peruan Yachachiq's – leaders of the rural communities experienced and trained in sustainable agriculture – have realized an excellent use for the waste of their cattle. They turn it into bio-gas, which can be directly used as a substitute for natural gas or firewood.
To be able to produce the animal bio-gas, the following is needed: a one by ten meters long container, the daily dung of either five cows or ten pigs, several gallons of water (depending on the animals diet) and an inside temperature of 35 degrees. The warm and wet environment is optimal for the bacteria inside the dung to thrive and multiply. They digest the manure anaerobicly – without oxygen – and thereby excrete a methane rich bio-gas. The gas fills up the top of the container and escapes through a PVC tube, that is directly linked to a gas cooker in the homes of the people.
Global warming by methane
The gas is not the only remainder after the bacteria's have feasted on the dung. A liquid fertilizer - biól - is a welcome byproduct that can be tapped from the digestor and used for growing potatoes and other vegetables. On the whole, a bio-digestor, is an excellent instrument to prevent deforestation and to manage animal waste. Methane is a greenhouse gas with a very high global warming potential. It is able to contain far more heat than CO2 does. Considering the massive amount of global livestock and the methane it produces, it is highly beneficial to capture and burn the methane into CO2 and at the same time use the energy from the process for cooking.
Project: Manure Bio-gas