biogás

Biogás is a renewable energy carrier produced by the anaerobic digestion of organic matter. It consists mainly of methane and carbon dioxide, with small amounts of water vapor and trace gases. The methane content typically ranges from about 50 to 70 percent, depending on feedstock and digestion conditions.

Biogas is produced in anaerobic digesters, where microorganisms break down organic material in the absence of oxygen. Common feedstocks include animal manure, crop residues, food waste, municipal organic waste, and sewage sludges. Digesters can be operated as batch or continuous systems and may run under mesophilic or thermophilic temperatures. The biological process advances through hydrolysis, acidogenesis, acetogenesis, and methanogenesis.

Biogas can be used to generate electricity and heat directly in combined heat and power plants, or burned for cooking and heating. It can be upgraded to biomethane, a pipeline-grade gas that can substitute natural gas or serve as a renewable vehicle fuel. The solid and liquid residue left after digestion, known as digestate, can be applied as a fertilizer or soil conditioner after proper treatment.

Biogas offers environmental benefits, including greenhouse gas emission reductions and better waste management. Its deployment depends on feedstock availability, regulatory support, and investment in digestion, gas handling, and grid or transport infrastructure. Risks include safety concerns due to flammability and the need to manage contaminants and inhibitors that can affect digestion performance.