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Energy Density of Ethanol

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Jolly, Lindsay. The Commercial viability of fuel ethanol from sugarcane [pdf]. International Sugar Organization. 2001. "The IEA did the cost comparison on the basis of per litre of gasoline equivalent indirect recognition of the fact that the energy density of ethanol (23.4 MJ/kg)" 23.4 MJ/kg
Gallons of Ethanol. The Energy Advocate, 1998. "Since the density of ethanol is 0.789 grams per cubic centimeter, the energy density of ethanol is 26.8 megajoules per kilogram." 26.8 MJ/kg
Thomas, George. Overview of Storage Development DOE Hydrogen Program [pdf]. Hydrogen Program Review. San Ramon, CA. May 9-11, 2000.
Fuel hydrogen weight fraction Ambient state Mass energy state (MJ/kg)
Ethanol 0.13 Liquid 26.8
26.8 MJ/kg

Ethanol, also known as grain alcohol or ethyl alcohol, is a clear and colorless liquid. Alcohols are a group of chemical compounds whose molecules contain a hydroxyl (OH) group. The chemical formla for ethanol is CH3CH2OH. Its low freezing point made it useful as the fluid in thermometers and for antifreeze in automobile radiators. It is a useful a solvent for making perfumes, paints, lacquer, and explosives. But ethanol is often used to make alcoholic beverages. Since ancient time, ethanol has been made by the fermentation of sugars, into alcoholic beverages like beer and wine. Some ethanol is not intended for drinking. Ethanol can be used as an automotive fuel by itself or mixed with gasoline to form gasohol.

Did you know that every time a bushel of corn is processed into ethanol both food and fuel can be produced? Ethanol as a fuel is produced by fermenting materials that contain starch from grains like corn, potatoes and sugarcanes. Currently in the United States, about 1.6 billion gallons of ethanol are produced each year. Ethanol use has increased because it is both biodegradable and renewable. It provides a better energy, environmental and economic resource. When the alcohol is used with gasoline it improves combustion and reduces carbon monoxide emissions.

Energy density is the amount of energy per mass. The greater the value the more beneficail the source is. The common unit of measurement for energy density is megajoules per kilogram (MJ/kg). The energy density of ethanol is about 25 MJ/kg.

Roxanne Garcia -- 2003