A method for recovering energy from biomass, in particular from vegetal biomass, by gasification, comprising: a drying step of the biomass; a pyrolysis step; a partial oxidation step; a reduction step; a gas treatment step; a combustion step; said steps being carried out in respective physically separated reaction stages; the method comprising the steps of: - recovering the heat required for the process from the gas coming out of the reduction step and from the exhaust gas coming out of the combustion step; - regulating thermal flows in the drying step independently of regulation of the heat reduction of the gas produced in the reduction step; - controlling the drying step, the pyrolysis step, the partial oxidation step and the reduction step so as to prioritize, in the following order: temperature reduction of the gas produced in the reduction step; recovery of thermal energy from the exhaust gases exiting from the combustion step; transfer of thermal energy to the drying step; and - detecting and processing: humidity and mass flow rate of the biomass to treat and flow rate of steam produced in the drying step, for calculating the mass flow rate of dried biomass sent to the pyrolysis step; temperature and residence time in the pyrolysis step and flow rate of the pyrolysis gases, for calculating the mass flow rate of the pyrolysis solid residue and then, once the ash percentage content is known, the quantity of char which passes to the reduction step and the quantity of steam needed in the reduction step; temperature of the partial oxidation step, for regulating the flow rate of air supplied to the partial oxidation step, i.e. of oxidising agent fed to the oxidation step, or determining the equivalence ratio; temperature profile and Δp trend in the thickness of a reduction char bed used in the reduction step, and flow rate of the gas produced in the reduction step, for determining the equivalence ratio, the flow rate of the steam and the quantity of residual pyrolysis char. a drying step of the biomass; a pyrolysis step; a partial oxidation step; a reduction step; a gas treatment step; a combustion step; said steps being carried out in respective physically separated reaction stages; the method comprising the steps of: - recovering the heat required for the process from the gas coming out of the reduction step and from the exhaust gas coming out of the combustion step; - regulating thermal flows in the drying step independently of regulation of the heat reduction of the gas produced in the reduction step; - controlling the drying step, the pyrolysis step, the partial oxidation step and the reduction step so as to prioritize, in the following order: temperature reduction of the gas produced in the reduction step; recovery of thermal energy from the exhaust gases exiting from the combustion step; transfer of thermal energy to the drying step; and - detecting and processing: humidity and mass flow rate of the biomass to treat and flow rate of steam produced in the drying step, for calculating the mass flow rate of dried biomass sent to the pyrolysis step; temperature and residence time in the pyrolysis step and flow rate of the pyrolysis gases, for calculating the mass flow rate of the pyrolysis solid residue and then, once the ash percentage content is known, the quantity of char which passes to the reduction step and the quantity of steam needed in the reduction step; temperature of the partial oxidation step, for regulating the flow rate of air supplied to the partial oxidation step, i.e. of oxidising agent fed to the oxidation step, or determining the equivalence ratio; temperature profile and Δp trend in the thickness of a reduction char bed used in the reduction step, and flow rate of the gas produced in the reduction step, for determining the equivalence ratio, the flow rate of the steam and the quantity of residual pyrolysis char. - recovering the heat required for the process from the gas coming out of the reduction step and from the exhaust gas coming out of the combustion step; - regulating thermal flows in the drying step independently of regulation of the heat reduction of the gas produced in the reduction step; - controlling the drying step, the pyrolysis step, the partial oxidation step and the reduction step so as to prioritize, in the following order: temperature reduction of the gas produced in the reduction step; recovery of thermal energy from the exhaust gases exiting from the combustion step; transfer of thermal energy to the drying step; and - detecting and processing: humidity and mass flow rate of the biomass to treat and flow rate of steam produced in the drying step, for calculating the mass flow rate of dried biomass sent to the pyrolysis step; temperature and residence time in the pyrolysis step and flow rate of the pyrolysis gases, for calculating the mass flow rate of the pyrolysis solid residue and then, once the ash percentage content is known, the quantity of char which passes to the reduction step and the quantity of steam needed in the reduction step; temperature of the partial oxidation step, for regulating the flow rate of air supplied to the partial oxidation step, i.e. of oxidising agent fed to the oxidation step, or determining the equivalence ratio; temperature profile and Δp trend in the thickness of a reduction char bed used in the reduction step, and flow rate of the gas produced in the reduction step, for determining the equivalence ratio, the flow rate of the steam and the quantity of residual pyrolysis char.