Wood gas is produced by the heating of wood. When wood burns in the stove, the wood gas escapes and is ignited by the flame. Therefore, the flame has a distance to the wood.
This is the area in which the wood gas mixes with oxygen, which flows in from below due to the rapid rise of the heated air. This principle is used in the extraction of wood gas to advantage, but prevents the formation of a flame in the gasifier by deprivation of oxygen. This allows the wood gas to be sucked off and used for combustion in an engine.
The engine is connected to a generator for the power generation; the rejected heat can be used for many heating or drying processes. The reasonable use of the rejected heat is the lynchpin of profitable wood power generation. The use of kinetic energy and waste heat enables the amazing efficiency of 82%.
This technology is not new, it was used in times of fuel shortage in vehicles.