Anaerobic digestion is the process by which microorganisms degrade organic and biodegradable wastes. During this process, three products are typically produced: biogas, biogas slurry and digestate.

Based on the latest livestock data released by China’s National Bureau of Statistics (NBS) in 2018, Based on the latest livestock data released by China’s National Bureau of Statistics in 2018, Wang et al.’s team concluded that if animal manure is used as the main feedstock for biogas production of biogas, the energy potential of manure biogas would be at least 5.74 × 10¹² megajoules, which is equivalent to about 4% of China’s total energy demand, using 2017 data as the basement.