NOVELTY - The method comprises carrying out a hydrolysis process (12) and an acidification process and then a methane formation process (14) in a spatially separated manner. The hydrolysis process takes place in a separate container. The supply of biomass (10) to the process and/or the removal of fermenting substrate (18) from the process take place in a discontinuous manner. The hydrolysis and acidification are carried out in a batch procedure in a common container. After the acidification, a fermentation process is carried out in a fermenter (16). A hydrolysis container is filled in a single process.    USE - Method for producing biogas e.g. methane gas during a multi-step process from solid biomass such as solid dung (80%), grass, clover-containing grass and/or grass from the landscape conservation (claimed).    ADVANTAGE - The method effectively increases biogas production by increasing the supply of hydrolyzed material from the hydrolysis container to the fermenter within very short time (2 hours) and enables economic production of biogas with increased yield.    DETAILED DESCRIPTION - The method comprises carrying out a hydrolysis process (12) and an acidification process and then a methane formation process (14) in a spatially separated manner. The hydrolysis process takes place in a separate container. The supply of biomass (10) to the process and/or the removal of fermenting substrate (18) from the process take place in a discontinuous manner. The hydrolysis and acidification are carried out in a batch procedure in a common container. After the acidification, a fermentation process is carried out in a fermenter (16). A hydrolysis container is filled in a single process and then the container is kept for two days on a temperature level. The pH value in the hydrolysis process is 3.5-5. After completion of the hydrolysis and acidification, the liquid material is fed into the hydrolysis container in the fermenter and/or fermenting container. The evacuation of the hydrolysis container and the feeding process into the fermenter take place over two days. Two parallel preliminary stages comprising the hydrolysis container and an acidification container are intended. The two hydrolysis containers are variably filled. The hydrolyzed biomass is fed to the fermenting container and/or fermenter after a defined period and in defined quantities and is placed for two days for the methane gasification. The fermenting substrate is used as fuel containing chips. The acidification container has a volume of 200 m3. The biomass fed to the acidification container is mixed by an agitator. An INDEPENDENT CLAIM is included for a plant for producing biogas during a multi-stage process.    DESCRIPTION OF DRAWING(S) - The diagram shows a schematic flow diagram for process steps of a method for producing biogas from biomass.    Supply of biomass (10)    Hydrolysis process (12)    Methane formation process (14)    Fermentation process in a fermenter (16)    Fermenting substrate. (18)