Ganglin Cao has completed his bachelor at the age of 23 years from Yulin University. He is a postgraduate in Lanzhou University of Technoloy. His major is Thermal engineering in China Northwestern Collaborative Innovation Center of Low-carbon Urbanization Technologies. He has published one papers in China Biogas.


It is environment-friendly and high-efficient way to cogenerate power and heat with biogas from the anaerobic fermentation process of cow manure. However, in Northwest China, it is difficult for a cogeneration system of heat and power, which is also called as Combined Heat and Power (CHP) to run normally during winter. Two generators are made in Czech Republic by an engineering company TEDOM, model Cento T88 SPE BIO, with a maximum power output of 76 kW and the power generation efficiency is 31.5%. But the heat from the exhausted gas is just not enough to preheat the feedstock and to maintain the thermostat for the anaerobic fermentation. Therefore, solar thermal collector and biogas boiler were introduced to a CHP built at Huazhuang town in Lanzhou City, Gansu Province, China and theoretical analysis was carried out to compare the economic performance of two auxiliary heating methods in this paper. we also did an economic study on the two assisted warming mode of solar collector and biogas boiler, while maintaining the temperature of the fermentation tank at 52ºC in summer and 37ºC in other seasons. The results showed that, the initial investment ratio of solar collector and biogas boiler auxiliary warming system is 4.02:1, and the net annual value of solar collector is 19.3% higher than the gas boiler. Taking into consideration, the premise including the relevant policies, economic and environmental benefits will provide sufficient solar energy in Northwest, whereas, energy of waste heat power generation recovery is insufficient hence, solar collector of biogas plant’s as an auxiliary warming system should be preferred.