Vesa Mikkonen February, 2011
Producing of suitable fuel for wood gas cars is difficult for most enthusiasts. In Finland various automatic wood chopping machines are today on sale and at least this "Superpilke" machine could be modified to produce suitable chunks for gas-generators on board of cars. Productivity was not bad, about 1.5 m3 readymade chunks in an hour. That means in about three days I am able to produce the fuel for entire year. To modify this machine only one part, the crankshaft operating the feeder, had to replaced to yield shorter cutting. That I could make by my self. Bad side is that this machine needs a lot of power and a tractor is needed to power it. The freezing weather (-30°C) stopped the work today.
For stationary power generation continuous feeding of chunks is difficult.
Chunks do well for batch operated wood gas-generators on cars, but for stationary power generation continuous feeding of chunks is difficult. For continuous fed small gasifiers I recommend chips to be used as a fuel because of the ease of production and ease of feeding into the gasifier.
The pictures show you how I produced chunks for my car yesterday. The double steel fence for drying (originally for concrete reinforcement) is 2.0 m in diameter and the height of the fence is 2.0 metres. Finnish birch has a density of 600 kg combustible matter / solid cubic meter in dry state. By the evening the fence was full, 6 m3 ready made fuel. The quality of the chunks is not very high by that should do for my car.
Regards from Finland