The work proposes a method of thermodynamic analysis of experimental modes on a set of design mode. This method makethe study the influence of gasification process parameters and optimise the gas generator operation possible. This approach can be used to study the operation of reactors differing in design and power, as well as to compare them with each other.The experimental results will be useful for validation of mathematical models. For the runs, complete data are given, sufficient for compiling mass and energy balances. The atypical modes of biomass gasification are attractive from a practical point of view. They are characterised by a compact reaction zone, high efficiency, low tar yields and stability of the gas composition with changes in reactor power. Keywords: biomass gasification; reactor; synthesis gas; solid fuel.