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Power output vs gasifier size

 
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Location: NEPa
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Unless I missed it, didn't see in the video on the Gasifier Builders Bible any mention that suggested what horse power engine could be supported by the design in the book. Does a scaling factor vs HP curve exist for supporting different size engines?

PS - Love the use of an O2 sensor and associated electronics for controlling carburetion.
 
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Thanks David,

The horsepower method of pairing isn't as favored as just pairing the gasifier's production capacity to the engines consumption capacity in liters. We have an engine sizing chart in the book that explains this more clearly. This design is best suited for 1-5 liter engines because of the size of the propane tanks we used for the shell. You can go a little smaller on engine size than 1 liter, but that is the general range.

Wood gasifiers produce a range of gas outputs based on the sizing of the jets and the diameter of the hearth opening. A quick change of the jets and the choke plate will allow you to match different engine sizes. Larger engines do need more suction to get started so I recommend 2 blower motors to get the gas producer up to operating temperatures quickly.
 
David Moyle
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I read where a rough rule of thumb is 33 HP/liter of engine displacement - so this gasifier runs 30-150 HP engines? That's pretty big - makes power generation seem feasible. How many pounds of wood per hour does it consume?
 
Ben Peterson
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You can turn 2-3 pounds of wood into a kilowatt hour depending on the engine size and rpm. Subtract out the water condensate to get an actual wood weight or it might seem heavier.

Those hp ratings are valid for petro fuels. Derate 30-50% for woodgas because of the nitrogen content and the fact that the engine is dragging air into the gasifier to make the gas. How tight your filter is will determine how much extra work the engine has to do to get the gas to it.

But even if you take a worse case scenario at 50% you still have some real power to play with.
 
David Moyle
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So, just to make sure I understand you, to support a 15 kW generator would require in the neighborhood of 40 lbs of seasoned wood per hour?
 
Ben Peterson
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David:

Yes that would be about the weight.
 
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