Methanol fuels consist of methyl alcohol, and can be used to power internal combustion engines or for other purposes. A number of different processes and raw materials can be used to make methanol fuels. The most common methyl alcohol in the past was created from wood, though methane gas and coal are often used. Methanol fuels are sometimes used in place of gasoline for racing applications, due to a lower volatility. Most of the attention paid to alcohol-based fuels has involved ethanol, though methanol can offer benefits such as increased sustainability and cheaper production.
It is possible to burn methanol fuels either alone or in combination with ethanol and gasoline. Methanol can be made from either sustainable or nonrenewable raw materials, while ethanol is made exclusively from renewable biomass. Ethyl alcohol is chemically identical to the alcohol ingested by people, but methyl alcohol is toxic. A common name for methanol is wood alcohol, since it was traditionally made through the destructive gasification of wood. It can also be made from methane found in natural gas, or the gasification of coal or various biomasses.
Methyl alcohol has a lower energy density than ethanol, and can also be more toxic. While ethanol can be ingested in moderation without doing extensive damage, methanol toxicity may cause blindness and other complications. Methanol may be absorbed if it comes into contact with the skin, and its vapors can cause toxicity if inhaled. Both types of alcohol fuels are hygroscopic, so they may absorb water molecules from the air if they are not tightly sealed.
The production of methanol fuels is typically less costly than ethanol variants, though advances are being made in the production of both. Ethanol was traditionally made from the same types of biomass that humans and livestock consume, such as corn and sugar cane. This could make ethanol expensive to produce, and raises concerns about a potential food crisis. Much of the methanol fuel in use is made from nonrenewable natural gas and coal, though biomethane is typically not made from edible biomass. Advances in ethanol production make us of other methods, such as cellulosic ethanol, that use non-edible vegetable matter.
Various racing circuits used methanol fuels as early as the 1960s. High speed crashes involving gasoline fueled vehicles tended to result in deaths due to the volatility of gasoline and the dark, opaque flames created when it burns. Methanol fueled vehicles involved in the same crashes were observed to burn less intensely, and with invisible flames. This could facilitate the rescue of trapped drivers. Methanol is still highly combustible, though the release of volatile organic compounds (VOCs) is typically lower than gasoline.