Economic analysis of pig farm biogas projects in China and Germany

Biogas projects of large & medium-scale husbandry farms are significant in reducing environmental pollution and getting access to renewable energy. However, they are all generally dependent on government subsidy in China, and their profitability is poor. In this work, we made contrastive analysis on the economy of pig farm biogas projects in China and Germany based on biogas fermentation steady-state model. Biogas fermentation process, generator efficiency and tariff are the key factors that affect economic efficiency. Currently, low electricity tariff [0.42 CNY·(kW·h)^-1] is the root cause for the loss of biogas projects. On the basis of improving the technology of biogas and power generation and reaching the level in Germany, changing the policy of giving construction subsidies without paying attention to operational efficiency to attaching importance to actual emission reduction and increasing tariff to 1.5 CNY·(kW·h)^-1 can shorten the payback period of the project within 3 years, which is of great importance to accelerating the development of biogas industry in China.