A thriving livestock sector provides abundant food but also generates large volumes of waste, polluting the environment and emitting greenhouse gases. Biogas technology offers a double solution: treating waste while producing renewable energy and organic fertiliser, closing the circular-economy loop in agriculture.
How biogas works
Biogas is produced through anaerobic digestion of organic matter, mainly livestock waste, in the absence of oxygen. Microorganisms break down the organic material and release a gas mixture in which methane (CH4) is the combustible component that provides energy. The process takes place in a sealed digester, yielding both fuel gas and nutrient-rich effluent.
Environmental and energy benefits
Biogas delivers several benefits at once, solving problems common to traditional livestock keeping.
- Treats waste and reduces odour and water pollution.
- Captures methane, a potent greenhouse gas, instead of releasing it freely.
- Provides fuel for cooking, heating or power generation.
- Produces effluent usable as quality organic fertiliser.
From cooking gas to electricity
At household scale, biogas is often used directly for cooking, replacing firewood or LPG, saving costs and easing pressure on forests. At larger farm scale, greater gas volumes can drive generators to power farm operations. Power generation from biogas suits concentrated livestock farms with high waste volumes and energy needs, though stable operation requires gas-treatment equipment and proper maintenance.
Effluent and organic fertiliser
An often-overlooked value of biogas is the digested effluent. The remaining liquid and sludge are nutrient-rich and can serve as organic fertiliser, improving soil and reducing chemical-fertiliser needs. Combining crops and livestock creates a closed loop: waste becomes energy and fertiliser, fertiliser nourishes crops, and crop residues return as animal feed, the model of a circular economy.
In circular agriculture, the waste of one process becomes the input of another; nothing is wasted.
Challenges in deployment
Despite the benefits, scaling biogas faces challenges: upfront cost, technical operation and maintenance demands, and gas output that fluctuates with temperature and feedstock. Gas safety must also be taken seriously. Appropriately sized designs, clear operating guidance and technical-support services are therefore essential for sustainability.
In line with promoting green agriculture and the circular economy, ASTRI Institute studies and transfers livestock-waste solutions, including biogas technology, working with households and farms to choose suitable models that reduce emissions and improve resource efficiency in agricultural production.