NOVELTY - The biogas plant for the production of biogas by fermentation, comprises a fermenter (2) in which a nutrient medium is introduced by a feeding device (10) having an unit for mixing the nutrient medium and gaseous medium, a pressure sensor (20) for recording pressure of the biogas, a control unit (30), which produces signals for regulating abundance quantity of the nutrient medium present in the fermenter, a gas pipeline through which the biogas taken from the gas storage area is supplied to an inlet of the mixing unit, and a heat exchanger (16).    USE - For the production of biogas by fermentation.    ADVANTAGE - The biogas plant has less operating and maintenance costs and ensures simple- and cost effective production of the biogas.    DETAILED DESCRIPTION - The biogas plant for the production of biogas by fermentation, comprises a fermenter (2) in which a nutrient medium is introduced by a feeding device (10) having an unit for mixing the nutrient medium and gaseous medium, a pressure sensor (20) for recording pressure of the biogas, a control unit (30), which produces signals for regulating abundance quantity of the nutrient medium present in the fermenter, a gas pipeline through which the biogas taken from the gas storage area is supplied to an inlet of the mixing unit, and a heat exchanger (16) by which the process warmth required to the fermentation is supplied to the nutrient medium. A sensor signal of the pressure sensor is led to the control unit, which compares the actual pressure of the biogas with a given predetermined pressure, which is equal to the atmospheric pressure. The regulation of the abundance quantity takes place via the supply and/or removal of the nutrient medium in or from the fermenter by regulating valves and/or feed pump. The fermenter has sampling points for entirely or partially fermented nutrient medium present in the fermenter. The regulating valves are openable and lockable by the control unit. The mixing unit is connected upstream of the fermenter and has a first inlet by which the nutrient medium is supplied to the mixing unit, a second inlet by which the gaseous medium is supplied to the mixing unit, and a third inlet by which the nutrient medium taken from the fermenter is supplied to the mixing unit. The second inlet of the mixing unit is connected to a gas compressor and/or a gas pump.    DESCRIPTION OF DRAWING(S) - The figure shows a biogas plant.    Fermenter (2)    Feeding device (10)    Heat exchanger (16)    Pressure sensor (20)    Control unit. (30)