There are several common ethanol fuel mixtures in use around the world. The use of pure hydrous or anhydrous ethanol in internal combustion engines (ICE) is only possible if the engine is designed or modified for that purpose. Anhydrous ethanol can be blended with gasoline (petrol) in various ratios for use in unmodified gasoline engines, and with minor modifications can also be used with a higher content of ethanol.
Ethanol fuel mixtures have "E" numbers which describe the percentage of ethanol fuel in the mixture by volume, for example, E85 is 85% anhydrous ethanol and 15% gasoline. Low ethanol blends, from E5 to E25, are also known as gasohol, though internationally the most common use of the term gasohol refers to the E10 blend.
Blends of E10 or less are used in more than twenty countries around the world by 2011, led by the United States, where almost all retail gasoline sold in 2010 was blended with 10% of ethanol. Blends from E20 to E25 have been used in Brazil since the late 1970s. E85 is commonly used in the U.S. and Europe for flexible-fuel vehicles. Hydrous ethanol or E100 is used in Brazilian neat ethanol vehicles and flex-fuel light vehicles and in hydrous E15 called hE15 for modern petrol cars in Netherlands
sembra che in D sia già in uso