NOVELTY - Biogas plant comprises a fermentation device, preferably a fermenter (1) comprising at least one fermentation container having a bottom and an outer wall enclosing the bottom, and at least one additional fermentation unit, storage unit and/or at least one gas storage (3) having at least one receptacle, where the receptacle laterally encloses the fermentation container of the fermentation device.    USE - Used as biogas plant.    ADVANTAGE - The biogas plant is safe, space saving and easy to operate.    DETAILED DESCRIPTION - INDEPENDENT CLAIMS are also included for:    (1) gas storage for the biogas plant, comprising a gas storage space for temporarily storing gas, where the gas storage space is surrounded by a central region such that the gas storage space gives a ring shape or helical shape, and the gas storage space is formed hose-like or tubular or by a pressure tight pipe;    (2) fermentation- and/or storage unit for fermenting and/or storing biomass and/or fermentation residues for the biogas plant, comprising receptacle having bottom and side walls, where an inner sidewall and an outer sidewall enclose the central region, the outer side wall is arranged spaced apart from the central region, and the bottom is substantially positioned between the inner- and the outer side wall;    (3) a dosing device for fermentation device of the biogas plant, comprising a dosing container (5), a push wall and a pushing mechanism, where the dosing container is divided by the push wall in an actuating compartment for receiving the pushing mechanism and in the receptacle for receiving biomass, having outlet for transporting biomass into the fermentation container, and the push wall is movable in the dosing container such that a volume of the actuating compartment and a volume of the receptacle are varied. The pushing mechanism is gradually moved perpendicular to the push wall;    (4) an introducing device for the biogas plant for introducing biomass into the fermentation container of the fermentation device, comprising a supplying unit for introducing biomass into the fermentation container, which is arranged in the region of a container lid of the fermentation container, and an introducing screw (6), which is at least partially located within the supplying unit, where the supplying unit is formed as support for supporting the container cover, which has flow channel for introducing biomass into the container along its longitudinal axis, and the support is vertically oriented with its longitudinal axis and/or is arranged centrally or displaced in the container;    (5) a heating device for tempering biomass and/or fermentation residues for the biogas plant, comprising fermentation- and/or storage unit having container and supplying unit for introducing biomass and/or fermentation residues into the container, which forms cylindrical flow passage, and at least one preheating means, where the preheating means is arranged on a surface of the supplying unit, which conducts biomass and/or fermentation residues, and/or in the supplying unit adjacent to the surface of the supplying unit of the fermentation- and/or storage unit, or the preheating means the surface of the supplying unit; and    (6) an agitating device for the biogas plant, comprising agitating tool for mixing biomass and/or fermentation residues, a support frame, and a gravity-substrate mixer having a container divided by a membrane, where the agitating tool and the region of the support frame are arranged in biomass and/or fermentation residues receiving fermentation- and/or storage container of the fermentation- and/or storage unit, and the container halves are filled with different media.    DESCRIPTION OF DRAWING(S) - The figure shows a schematic external view of the biogas plant.    Fermenter (1)    Secondary fermenter (2)    Gas storage (3)    Dosing container (5)    Introducing screw (6)