What Is Ethanol and How Is It Made?
Most people probably remember from high-school biology that ethanol is a chemical made when yeast breaks down sugar molecules in a process called fermentation. Ethanol has two carbon atoms, six hydrogen atoms, and one oxygen atom. There are various kinds of alcohol, but ethanol is the one found in your beer, wine, and spirits. It is also combustible, which is well known to anyone who has set brandy on fire while cooking–think Cherries Jubilee. Alcohols like ethanol and its chemical cousins make effective fuels because they give off a lot of energy when burned, just as liquid fossil fuels do. The advantage of alcohol is that it is liquid at room temperature, which makes it easy to transport and handle. Ethanol can be made in a variety of ways, but the usual way is still the most common: yeast is fed sugar molecules isolated from fruits or vegetables, and it produces ethanol as a byproduct. The ethanol is then distilled from a dilute solution by controlled heating in order to drive off
