NOVELTY - Producing biogas for a feed distribution system or natural gas distribution system, comprises (a) anaerobic digestion of organic matter, (b) storing produced buffer biogas in storage (2), (c) transferring the biogas via a transfer line, (d) purifying the biogas provided during the step (c), and (e) distribution of feed or natural gas via an injection station equipped with at least one biomethane counting and analyzing unit and a network protection unit against over-pressure.    USE - The process is useful for producing biogas, preferably biomethane for a feed distribution system or natural gas distribution system (claimed).    ADVANTAGE - The process economically produces the biomethane with high yield in an eco-friendly manner.    DETAILED DESCRIPTION - Producing biogas for a feed distribution system or natural gas distribution system, comprises (a) anaerobic digestion of organic matter, (b) storing produced buffer biogas in storage (2), (c) transferring the biogas via a transfer line, (d) purifying the biogas provided during the step (c) to produce biomethane for the feed distribution system or natural gas distribution system, and (e) distribution of feed or natural gas via an injection station equipped with at least one biomethane counting and analyzing unit and a network protection unit against over-pressure including at least an automatic valve for interrupting the injection of biogas when the gas pressure in the network exceeds a critical pressure defined by the network operator. The method further comprises controlling and adjusting the biogas in the step (d) by (i) measuring the amount of biogas in storage, and (j) adjusting the biogas flown in the step (d) according to the amount of biogas measured in the step (b) to maintain or restore the amount of biogas to a stored value corresponding to a optimal minimum amount (Qopt) defined by the producer. An INDEPENDENT CLAIM is included for an installation for implementing the method comprising a supply of organic material, a digester (1) to produce biogas from organic matter, a biogas product buffer storage unit, a purification unit (6) for purifying biogas into biomethane, the feed distribution system, the natural gas distribution system, a line for transferring biogas from the storage to the unit to purify the biogas into biomethane, and a line for transferring the biomethane from the unit for purifying the injection station, where the installation further comprises an unit for measuring the amount of biogas in the buffer storage, and an unit for adjusting the biogas flown from the purification unit.    DESCRIPTION OF DRAWING(S) - The figure shows a block flow diagram of a process for producing biogas.    Digester (1)    Storage (2)    Flare (5)    Purification unit (6)    Recycle line. (8)