NOVELTY - The method comprises producing a synthesis gas from a carbonaceous material by performing a reforming operation of an intermediate gas flow from the carbonaceous material, where the synthesis gas flow includes hydrogen and carbon monoxide and the synthesis gas has a first molar flow rate under first operating conditions for the reforming operation, and producing a hydrogen flow from a hydrogenated raw material and a first electric power consumption, where the hydrogen flow has a first molar flow rate for the first electric power consumption.    USE - The method is useful for the production of methanol and/or hydrocarbon from a carbonaceous material including coal, lignite, municipal waste, animal waste, biomass, and plastics such as polyethylene or polyethylene terephthalate.    ADVANTAGE - The method ensures effective and easy production of the methanol and/or hydrocarbon from the carbonaceous material with high quality and production yield and reduced electricity consumption.    DETAILED DESCRIPTION - The method comprises producing a synthesis gas from a carbonaceous material by performing a reforming operation of an intermediate gas flow from the carbonaceous material, where the synthesis gas flow includes hydrogen and carbon monoxide and the synthesis gas has a first molar flow rate under first operating conditions for the reforming operation, producing a hydrogen flow from a hydrogenated raw material and a first electric power consumption, where the hydrogen flow has a first molar flow rate for the first electric power consumption, producing the methanol and/or hydrocarbons from synthesis gas and the hydrogen gas flow, lowering the first electric power consumption to produce the hydrogen flow until a second electric power consumption is lower than the first electric power consumption, where the hydrogen gas flow has a second molar flow rate for the second electric power consumption, and subjecting the synthesis gas under second operating conditions that are different from the first operating condition for reforming to compensate the drop down of the molar flow rate of the hydrogen flow. The second molar ratio is lower than the first molar flow rate. The synthesis gas further has a second molar flow rate that is higher than first molar flow rate under the second operating conditions. The reforming operation is carried out: at a first temperature and a first pressure under the first operating conditions; at a second temperature and a second pressure under the second operating conditions, where the second temperature is lower than the first temperature and the second pressure is lower than the first pressure; and in a reforming unit for receiving an input stream containing organic molecules and for receiving different input streams on a total molar flow of carbon atoms contained in the organic molecules and a total molar water flow and oxygen flow. A ratio of the total molar water flow rate on the total molar flow rate of carbon atoms contained in the organic molecules is equal to a first value under the first operating conditions and is equal to a second value under the second operating conditions. The second value is 1.5-3 times than the first value. The hydrogen flow is produced from electricity supplied by an electric distribution network. The intermediate flow is obtained by gasification of the carbonaceous material. An INDEPENDENT CLAIM is included for an installation of production of methanol and/or hydrocarbon from a carbonaceous material.    DESCRIPTION OF DRAWING(S) - The diagram shows a schematic view of an installation for production of hydrocarbon.    Synthesis gas production unit (10)    Conditioning unit (12)    Adding unit (14)    First product stream production unit (16)    Electrolysis unit. (22)