Wood-burning stoves once fueled autos

In the World War II the Japanese ran their automobiles on fuel which was generated by a wood-burning stove attached near the engine. I would like more information on the process and how to build such a burner. Not long ago there was a news item about a van being driven across the US by burning wood for fuel. How about it? Edwin C. Schisler Manchester, Mo.

You're right in saying that the Japanese used a gasification system to run their automobiles during World War II. In fact, I can well recall seeing cars in Australia in 1944 and '45 with charcoal stoves on the back of them. Gasification systems also were widely used in Germany, France, the Soviet Union, and Sweden.

Well over 800,000 vehicles were so equipped, I'm told by the General Motors Technical Center in Warren, Mich. In the US, however, only 6 vehicles were reported to operate on automotive gas producers in 1942.

Clearly, liquid fuels were not as scarce in the US at that time.

Despite some advantages to such a system, there are problems, I'm told. Likely problem areas for the operation of automotive gas producers are the solid fuel feed mechanism, tar and clinker formation in the gasifier, line plugging, gas filtration, and engine durability.

"Frequent maintenance and atmospheric emissions are also problems which would need to be addressed in addition to the standardization, manufacture, and distribution of the fuel," asserts William Agnew of the GM facility.

Gasification, in very general terms, is the controlled, partial combustion of the fuel. The process uses the intense heat of partial combustion to break molecular bonds in the fuel, thus transforming the solid fuel to a gaseous fuel. The gasification products of solid fuels with air are a low-heating-value gas commonly called producer gas.

The internal-combustion engines of automobiles and trucks can be converted to use producer gas, asserts Dr. Agnew.

As a matter of fact, gasifiers were first developed in the mid-19th century in Germany. Toward the end of the century, stationary producers were being used to gasify both wood and coal. Most of these producers were of the updraft type with air forced into the bottom of the reactor and gas discharged at the top. The producer gas was either directly combusted in a furnace or boiler, or cleaned and cooled to operate an internal-combustion engine.

During World War II the most successful portable gasifiers were the downdraft versions, which had lower tar production. After the war, however, they were abandoned because of the ready availability of gasoline and natural gas.

While anthracite, coke, charcoal, and wood are among the solid fuels widely used in the 1940s in Europe for automotive gas producers, charcoal was the most successful because of its low ash content, ease of gasification due to the high porosity of the fuel, and less tar.

Even though a wood-burning car did make a cross-country trip a few months ago , such a system would be cumbersome and uninviting to almost all motorists these days. I know of no plans for such a conversion.

If you want more information, you can write to Dr. William Agnew, General Motors Technical Center, Warren, MI 48090.

If you have a question on how to save energy -- in your home, your car, on the water -- send it to ENERGY, The Christian Science Monitor, One Norway Street , Boston, MA 02115.

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