Click HERE for an 86K JPG image of a wood gas generator equipped Kubelwagen and Type 60 Beetle.
Fuel shortages during WWII prompted searches for alternative fuels in England, Germany, Scandinavia and many other countries. One of the most unusual solutions involved the modification of vehicles for use with wood, charcoal, or coal. Typical modifications included A) a gas generator; B) a gas reservoir; and C) carburetor modifications and additional plumbing to convey, filter, and meter the gas into the engine.
The gas generator was an airtight vessel into which was introduced a charge of wood, charcoal, or anthracite coal. Heat was applied to the fuel either internally or externally to initiate a self-sustaining gassification of the fuel in an oxygen deprived environment. The resulting "woodgas" was piped to the reservoir, or in the case of small engines, directly to the engine carburetor. Wood-gas modified vehicles were therefore technically a "dual fuel" vehicle in that a self-sustaining gassification of the wood charcoal, or coal required another fuel to start the process.
Gas reservoir sizes depended upon vehicle, engine, and gassifier size. Small vehicles and engines could be supplied directly from the gassifer, thus eliminating large reservoirs. Larger, more powerful vehicles required separate gas reservoirs to compensate for gassifer outputs which were less than the fuel consumption rate of the engine. These larger reservoirs usually took the form of gas bags that were attached to the roof or rear end of the vehicle. The largest mobile reservoirs were gas bags fitted to busses which were often several feet in diameter and as long as the vehicle.
Although the designation T230 was used to indicate woodgas fuel systems fitted to both Kubelwagens and KdF Wagens (Type 60 wartime Beetles), surviving phototgraphs reveal that a variety of gas generator designs and hood sheet metal were employed. Vehicles so equipped are easily recognized by the vehicle's modified hood (28K JPG). Some photos show that the fuel loading hatch protruded from a port in the hood, while others illustrate an unbroken hoodline which completely enclosed the generator. Generally the woodgas fuel system comprised a gassifier container (20K JPG) approximately 18 to 24 inches in diameter and 30 to 36 inches in length (height) fitted into the nose of the vehicle. Both Kubelwagens and Beetles equipped with the T230 gas generator located the generator vessel ahead of the front axle beams where the spare tire was formerly located. Type 60's relocated the spare tire, along with extra bags of fuel, to a roof rack (28K JPG) on the roof of the vehicle. The bottom of the gas generator also extended below the original bodywork at the front of the vehicle, thus decreasing obstacle clearance.
Other components of the VW T230 woodgas fuel system included:
1) a large (8" diameter by 30") gas filter cannister located just ahead of the windshield (and under the hood, in the case of the Type 60)
2) a secondary, rectangular gas filter (about 12" by 2" by 48") located crossways beneath the car behind the front wheels
3) a gas pump or fan located behind the rear torsion bar tube
4) a small final cannister filter in the engine bay
5) a fuel mixer at the engine intake manifold.
Click HERE for an 80K GIF of a wood-gas powered Kubelwagen.
Click HERE for a 77K GIF of a wood-gas powered VW Beetle that probably was fitted with four wheel drive!
My thanks for Chris Horn for loaning me his copy of VW Beetle At War by Dr. Hans-Georg Mayer (ISBN: 0-88740-400-6), from which much of the information on this page was gleaned. If you are interested in learning more about wartime VW Beetles, I highly recommend Dr. Mayer's book, available from Schiffer Publishing Ltd., 1469 Morstein Road, West Chester, PA, 19380, USA.
Information on wood gassifer equipped vehicles is limited, and I am currently looking for gassifer construction details, fuel metering details, and pictures of vehicles so equipped. If you know of any such information, or if you can direct me to manufacturing firms who currently produce such systems, please let me know!