NOVELTY - Village household biogas system with auxiliary heating function of solar energy in villages, comprises a solar water heater (1), a circulating water pump (2), a three-way valve (3), a valve (4), a heat exchanger (5), a stirring device, a biogas pool and a control cabinet. The heat exchanger is coaxial with the stirring device which is arranged on the inner side of the heat exchanger. The water outlet port of the water tank of the solar water heater is connected to circulating water pump and water inlet three-way valve.    USE - The household biogas system is used in villages.    ADVANTAGE - The biogas system uses artificially set winter or summer working mode, and are processed by passing the solar energy passes into the biogas pool, and the solar water heater and the biogas pool are individually worked.    DETAILED DESCRIPTION - Village household biogas system with auxiliary heating function of solar energy, comprises a solar water heater (1), a circulating water pump (2), a three-way valve (3), a valve (4), a heat exchanger (5), a stirring device, a biogas pool and a control cabinet, where the heat exchanger and the stirring device are arranged in the biogas pool. The heat exchanger is coaxial with the stirring device which is arranged on the inner side of the heat exchanger. The water outlet port of the water tank of the solar water heater is connected to the circulating water pump, the water inlet three-way valve, the valve and the water inlet end of the heat exchanger in turn via pipes. The water outlet end of the heat exchanger is connected to the valve, the water refluxing three-way valve and the water inlet port of the water tank of the solar water heater in turn via the pipes. The water tank of the solar water heater and the biogas pool have temperature testing points, where the temperature testing points, the water pump and the stirring device signal wire are connected to the control cabinet.    DESCRIPTION OF DRAWING(S) - The drawing shows a schematic representation of the village household biogas system with auxiliary heating function of solar energy.    Solar water heater (1)    Circulating water pump (2)    Three-way valve (3)    Valve (4)    Heat exchanger (5)