NOVELTY - The gasification plant (15) has a gas cleaning device that is connected with fixed bed reactor (3). The carbonization and/or evaporation chamber (22) is provided with the chambers (26,27) which are heated using the heat dissipated from fixed bed reactor such that impurities such as tar and other long-chain hydrocarbons separated from useful gas (14) is carbonized and evaporated. The carbonization and/or evaporation chamber is connected with fixed bed reactor through thermally gas-insulated conduit (23) such that carbonized impurities are supplied to interior of reactor.    USE - Thermo-chemical wood gasification plant for auto-thermal production of usable energy gases from biomass of wood, wood chip, bark, sludge, pellet, impregnated or treated wood, compost waste, industrial waste, cellulose-like chemical compounds and stalks, used for operating piston motor and gas turbine used in vehicle. Can also be used in grain or corn straw and other waste products of cultivation of agricultural crops such as giant Miscanthus, organic industry and household waste, vegetable oils, starch, animal excrements such as slurry and manure.    ADVANTAGE - The efficient production of usable energy gas from biomass can be ensured. The gasification efficiency can be improved. The yield of the usable energy gas can be improved. The waste heat can be utilized efficiently. The environmental protection can be ensured by reducing the carbon dioxide emission. The separated crude gas and hydrocarbons can be vaporized or carbonized efficiently. The quality and calorific value of the produced gas can be improved by increasing the proportion of oxygen in the combustion air provided inside the reactor. The continuous operation of the piston motor can be ensured. The piston motor can be maintained easily. The pollutant disposal cost can be reduced. The turbulence generated during outflow of the product gas can be reduced. The ash or dust in the useful gas can be separated easily.    DETAILED DESCRIPTION - An INDEPENDENT CLAIM is included for thermo-chemical wood gasification method for production of usable energy gases.    DESCRIPTION OF DRAWING(S) - The drawing shows a schematic view of the thermo-chemical wood gasification plant.    Fixed bed reactor (3)    Useful gas (14)    Gasification plant (15)    Carbonization and/or evaporation chamber (22)    Thermally gas-insulated conduit (23)    Chambers (26,27)