The supply rate goal for new and renewable energy has been set to 20% by 2030 through the expansion of biogas production. The goal to reduce CO2 and greenhouse gas emissions by 37% below the business-as-usual (BAU) level of 851 million by 2030 was set by the Korean Government. However, biogas from corresponding treatment facilities is not used for the purpose of energy production, but is incinerated to raise the temperature of digesters. This study aimed to conduct a simulation of a solid oxide fuel cell (SOFC) hybrid plant using actual biogas operation data, analyzing annual performance. The 2450 kW SOFC system was set to its maximum capacity, with the available amount of biogas and the heat of the exhaust gas used to heat the anaerobic digester, but the amount of digester heat decreased in summer because of high air temperature. Up to 55% of total power usage could be produced via biogas, and a 45% reduction in CO2 was achieved.