Summary of Genset Options for Wood Gas


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Many of us have gone round and round on what engines to choose for woodgas gensets.  There is a long thread on this here in the GEK forum: http://gekgasifier.com/forums/showthread.php?t=14  None of the choices are ideal, but many are tolerable.  Below is a general summary of options.   Click here for an inventory of specific genset models and sellers

 

See also our How to Convert an Engine or Generator to Wood Gas page for what to do once you have an engine.

 

For inspiration, here's us running a 10kW Honda V Twin gen set recently:

 

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Characteristics of the perfect wood gas engine / genset:

 

 

The usual cheap DIY options:

 

 

Dual fuel is not turning out to be very reasonable at the small scale.  So you can either start with a spark engine and have lower than ideal compression ratios, or start with a direct injection diesel engine and convert to spark.

 

An outlier in the "convert a diesel realm" is the detroit diesel 2-71.  These were common heavy industrial gensets, of near eternal life expectancy.  Most interestingly for woodgas, they are two stroke, thus do not have intake valves to foul.  They do, however, have a blower, and that has bearings that might be foulable.  Not sure if the pressure side of the blower would encourage tarry gas into the bearing housing.  Here's one dealer of these: http://affordablepower.com/Generators.htm

 

 

The best DIY options:

 

 

Either of these scenarios can be set up with pulley drive or direct Lovejoy drive.  Regular V pulleys are likely better for developed world.  Lovejoy direct drive is likely better for places where they can be easily sourced.  We've done both and are not strongly convinced of one method or the other.  The V belt drive creates the option for ratio changes so the engine can be set to run in its desired zone, not just 1800 or 3600.

 

Here's how we currently combine all this into an integrated gasifier / genset:

http://www.youtube.com/watch?v=0JrLbu3Ndyw

 

 

 

The best off-the-shelf option

 

Natural gas or LP gensets in the lower RPM variety are a reasonable match.  You do not need the LP or natural gas mixer, as the woodgas requires a different set up, but the rest of the engine is well suited to your needs.  There are often 2200 RPM LP generators for RV use.   Then there are proper 1800 RPM LP and natural gas generators for industrial use, which will often have higher compression. Natural gas and LP are more detonation resistant than gasoline.  See here for our inventory of lp / nat gas genset models and sellers of interest.