This 17 minute video shows a homemade wood gasifier that puts out enough gas to run a small generator. This is his second version with some improvements. The gasifier can use wood chips, sawdust, leaves, paper, etc., but he is using wood pellets which are already dry.
The gasifier produces syngas when wood is pyrolyzed in a low oxygen environment.
The 12 volt blower squirrel cage fan from a car heater provides airflow. But it requires a battery and the battery must be kept charged. Maybe the generator has a 12 volt output? Or else run a 5 amp charger off the 120VAC from the generator. He injects the gas directly into the air intake of the carburetor. It needs to have a fine screen filter in front of the carburetor to prevent damage to the engine.
Another similar gasifier.