Wood gas

Wood gas is a syngas fuel which can be used as a fuel for furnaces, stoves and vehicles in place of gasoline, diesel or other fuels. During the production process biomass or other carbon-containing materials are gasified within the oxygen-limited environment of a wood gas generator to produce hydrogen and carbon monoxide. These gases can then be burnt as a fuel within an oxygen rich environment to produce carbon dioxide, water and heat. In some gasifiers this process is preceded by pyrolysis, where the biomass or coal is first converted to char, releasing methane and tar rich in polycyclic aromatic hydrocarbons.

The first wood gasifier was apparently built by Gustav Bischof in 1839. The first vehicle powered by wood gas was built by Thomas Hugh Parker in 1901. Around 1900, many cities delivered syngas (centrally produced, typically from coal) to residences. Natural gas began to be used only in 1930.

Wood gas vehicles were used during World War II as a consequence of the rationing of fossil fuels. In Germany alone, around 500,000 "producer gas" vehicles were in use at the end of the war. Trucks, buses, tractors, motorcycles, ships and trains were equipped with a wood gasification unit. In 1942, when wood gas had not yet reached the height of its popularity, there were about 73,000 wood gas vehicles in Sweden, 65,000 in France, 10,000 in Denmark, and almost 8,000 in Switzerland. In 1944, Finland had 43,000 "woodmobiles", of which 30,000 were buses and trucks, 7,000 private vehicles, 4,000 tractors and 600 boats. Although charcoal was preferred for cars in China during the oil shortages.

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Wikipedia