NOVELTY - Automatic solar biogas fermentation comprises: delivering the excrement mixture of the excrement storage pit (1) to the material tank of the hydrolysis acidification treatment tank (4) for hydrolysis acidification treatment and stirring the excrement storage pit with a stirrer, delivering the excrement mixture treated by the hydrolysis acidification treatment tank to the material tank of the anaerobic digestion tank (5), stirring and fermenting in the anaerobic digestion tank, installing the stirrers (6) on the hydrolysis acidification treatment tank and anaerobic digestion tank.    USE - The method is useful for automatic solar biogas fermentation.    ADVANTAGE - The automatic solar biogas fermentation method is environment-friendly. The method has the automation control over the biogas feed, agitation and discharge of the fixed quantity of biogas at a constant temperature.    DETAILED DESCRIPTION - Automatic solar biogas fermentation comprises: (a) delivering the excrement mixture of the excrement storage pit to the material tank of the hydrolysis acidification treatment tank for hydrolysis acidification treatment by the automatic feed delivery pump to ferment the excrement mixture and stirring the excrement storage pit with a stirrer; (b) delivering the excrement mixture treated by the hydrolysis acidification treatment tank to the material tank of the anaerobic digestion tank by the automatic feed pump, stirring and fermenting in the anaerobic digestion tank; (c) installing the stirrers on the hydrolysis acidification treatment tank and anaerobic digestion tank; (d) delivering the hot water to the water collecting inter-layer (8) between the hydrolysis acidification treatment tank and the anaerobic digestion tank by the solar heat collector through a temperature control pump and a solar hot water circulation system, and delivering the hot water to the excrement storage pit by the solar heat collector through the temperature control pump and the solar hot water circulation system; (e) introducing the gas produced in the anaerobic digestion tank to a desulfurization device for eliminating hydrogen sulfide and sulfur dioxide from the gas, and then guiding the gas to the water collector for removing the condensed water and injecting the gas into the storage tank for application by the user; (f) discharging the waste material in the material tank of the anaerobic digestion tank after gas generation to the solid-liquid separator by a hydraulic automatic control discharge switch for solid-liquid separation, using the separated material as the biological fertilizer; (g) installing the heat insulation materials on outer walls of the hydrolysis acidification treatment tank and the anaerobic digestion tank; and (h) finishing the control work of all device by the automatic control cabinet.    DESCRIPTION OF DRAWING(S) - The figure shows a schematic representation of a process flow diagram of an automatic solar biogas fermentation method.    Excrement storage pit (1)    Hydrolysis acidification treatment tank (4)    Anaerobic digestion tank (5)    Stirrers (6)    Water collecting inter-layer (8)