Work out biogas yield from dung instantly with clear inputs, formula shown and shareable results.
Gas comes from volatile solids, not from wet weight. Cattle dung is 16-20% total solids of which about 80% is volatile, and each kilogram of volatile solids yields 0.2-0.3 m3 of biogas at 55-65% methane. Methane's calorific value of about 9.94 kWh/m3 converts that to usable heat.
Biogas yield
VS = dung x TS % x VS share; biogas = VS x yield per kg VS
Energy
Methane = biogas x 60%; energy (kWh) = methane x 9.94
Biogas mixtures with air are explosive. Gas piping, valves and appliances must comply with the applicable code and be leak-tested before use.
Drying loses volatile solids to the air and starts aerobic decomposition. Dung collected and fed the same day gives noticeably more gas per kilogram.
Strongly. Mesophilic digestion peaks near 35 C; below about 20 C gas production can halve, which is why cold-climate plants are insulated or heated.