Biogas is a gas produced by means of anaerobic digestion of biomass. Microorganisms metabolize carbon from organic substrates in oxygen-free environment (anaerobic). This process is also called rotting or oxygen-free digestion and follows the food chain. Biogas is a gas that consists of approximately 60% methane (CH4) and 40% of carbon dioxide (CO2). Synonyms for biogas are terms like sewer gas, mine gas, marsh gas, and methane gas. Caloric value of biogas ranges between 6000 to 7500 kcal

Biogas can be utilized for electricity or heat production. The most common biogas application is a fuel in co-generation plants with internal combustion engines.  

Biogas can be cleaned from CO2 and up-graded to the properties of natural gas . This purified gas is called biomethane.

Table. Main biogas perfromances

Energy in 1 m3 of biogas 6-6,5 kWh
Heat value ability4500-6300 ccal /m3
Biogas density1,16-1,27 kg / m3
Burning temperature650-750 С
Biogas pressure in a reactor0,05 atm