Ed. note: This post, about ethanol is now the third post (read about biodiesel and compost to catch up) in the Green Basics series of posts that TreeHugger is writing to provide basic information about important ideas, materials and technologies for new greenies (or those who just need a quick refresher). Read on and stay tuned!
Ethanol as fuel
Ethanol is also known as ethyl alcohol, the same kind of alcohol you shake with vermouth and serve with some olives. Used as a fuel, it is often added to gasoline (notated much the same as biodiesel: E10 means 10% ethanol; E85 means 85% ethanol, and so on). Most gasoline-burning car engines on the road today will operate on E10 gasoline without modification, and most of the ethanol produced in the world today is "bio-ethanol," or ethanol derived from the starch or sugar in a wide variety of common crops, or feedstocks. Most commonly, ethanol is made by fermenting sugar with yeast (just as drinking alcohol is), distilling it to remove most or all of the water and then usually denaturing it (this steps isn't required to make fuel), altering it so that more than a swig will land you in the hospital. So don't drink it.What is ethanol?
Compared with conventional unleaded gasoline, ethanol is a particulate-free burning fuel source that combusts cleanly with oxygen to form carbon dioxide and water. Use of ethanol, produced from current methods, emits a similar net amount of carbon dioxide but less carbon monoxide than gasoline.
Keep reading to learn more about who's making it, corn and other feedstocks, and ethanol's effects on fuel prices.