Section 5. Wartime Research and Production
Item 3. Research on Alternative Fuels
Demand for automobiles in Japan started to increase rapidly following the Great Kanto Earthquake in 1923, and automobile ownership exceeded 100,000 vehicles by the end of August 1933. As a result, gasoline consumption also grew quickly, and securing fuel became a major problem. In 1934, when Toyoda Automatic Loom Works, Ltd. began producing prototype automobiles, Japan relied on imports for 80 percent of its crude oil, and when imports of refined petroleum products are included, 86 percent of all petroleum products demand was imported. Oil is a strategic material, and restrictions were imposed following the Manchurian Incident in 1931. The Petroleum Industry Law came into effect in July 1934, and oil refining and importing became licensed businesses.
In response to these developments, extensive research was conducted on fuels that could take the place of gasoline, and research on electric vehicle storage batteries and diesel engines was also performed as a part of those efforts. Among the alternative fuels considered were charcoal, wood, Coalite (semicoke; a low-temperature carbonization byproduct of coal), charcoal briquettes, anthracite, brown coal, acetylene gas (carbide), natural gas, alcohol, etherified alcohol, and man-made oil. Of these, the Ministry of Commerce and Industry provided a subsidy (up to 300 yen) from 1934 to users of gas generating devices that used charcoal and wood.
In the Automotive Department of Toyoda Automatic Loom Works, Kichihei Miki1, the inventor of a wood gas generating furnace, conducted research at the Shibaura Laboratory starting in 1936. According to an article authored by Miki and entitled 'Wood-Burning Vehicles and Coal-Burning Vehicles'2, a fully-loaded 2-ton truck driven 100 kilometers consumed 20 to 25 liters of gasoline (4 to 5 kilometers per liter) or 40 to 50 kilograms of wood (2 to 2.5 kilometers per kilogram), indicating that 1 liter of gasoline was equivalent to about 2 kilograms of wood. One can of gasoline (18 liters) cost 1.8 yen, while 3,750 kilograms of wood cost 30 yen, and if the truck were driven 100 miles (160 kilometers) each day, over the course of the year, the gasoline would cost approximately 1,500 yen while the wood would cost approximately 250 yen, a savings of 1,250 yen annually by using wood.
In about 1936 when Miki began his research at the Shibaura Laboratory, charcoal-powered vehicle technology was undeveloped and could not produce adequate output, but as a result of subsequent advances, performance improved substantially. The July 1939 issue of Ryusenkei publicity magazine reported in an article entitled "Charcoal-Powered Vehicle Quality Improves" that a coal-fueled vehicle performed well in tests conducted by the Ministry of Railways.3 Toyota Motor Co., Ltd. continued research on charcoal gas generating furnaces and produced a prototype model AX charcoal gas generating furnace in February 1945.4
Meanwhile, anhydrous alcohol, an alternative fuel, was combined with gasoline in a 10 percent mixture starting in July 1938. In response, Toyota Motor Co., Ltd. developed a timing device that appropriately adjusted the ignition timing for gasoline mixed with alcohol and obtained a patent in February 1940.5