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Side-by-side comparison of section of ethanol between GA version and 080111 version

GA version 071009 Current 081011

As a fuel

[edit]

The largest single use of ethanol is as a motor fuel and fuel additive. The largest national fuel ethanol industries exist in Brazil (gasoline sold in Brazil contains at least 20% ethanol and hydrous ethanol is also used as fuel).[1]

Today, almost half of Brazilian cars are able to use 100% ethanol as fuel, which includes ethanol-only engines and flex-fuel engines. Flex-fuel engines are able to work with all ethanol, all gasoline, or any mixture of both. Brazil supports this population of ethanol-burning automobiles with large national infrastructure that produces ethanol from domestically grown sugar cane. Sugar cane not only has a greater concentration of sucrose than corn (by about 30%), but is also much easier to extract. The bagasse generated by the process is not wasted, but is utilized in power plants as a surprisingly efficient fuel to produce electricity.

World production of ethanol in 2006 was 51 billion liters, (13.5 billion gallons), with 69% of the world supply coming from Brazil and the United States.[2]

The United States fuel ethanol industry is based largely on maize. According to the Renewable Fuels Association, as of November 2006, 107 grain ethanol biorefineries in the United States have the capacity to produce 5.1 billion gallons of ethanol per year. An additional 56 construction projects underway (in the U.S.) can add 3.8 billion gallons of new capacity in the next 18 months. Over time, it is believed that a material portion of the ~150 billion gallon per year market for gasoline will begin to be replaced with fuel ethanol.[3]

The Energy Policy Act of 2005 requires that 4 billion gallons of "renewable fuel" be used in 2006 and this requirement will grow to a yearly production of 7.5 billion gallons by 2012.[4]

A Ford Taurus "fueled by clean burning ethanol" owned by New York City.

In the United States, ethanol is most commonly blended with gasoline as a 10% ethanol blend nicknamed "gasohol". This blend is widely sold throughout the U.S. Midwest, and in cities required by the 1990 Clean Air Act to oxygenate their gasoline during the winter.

As a fuel

[edit]

The largest single use of ethanol is as a motor fuel and fuel additive. The largest national fuel ethanol industries exist in Brazil (gasoline sold in Brazil contains at least 20% ethanol and anhydrous ethanol is also used as fuel).[1]

Henry Ford designed the first mass-produced automobile in the US, the famed Model T Ford to run on pure anhydrous [ethanol] alcohol -- he said it was "the fuel of the future". Today, however, 100 % pure ethanol is not approved as a motor vehicle fuel, even though compared to gasoline, ethanol cuts poisonous gas emissions [carbon monoxide, nitrous oxides, sulfur dioxide] and produces fewer greenhouse gases that cause global climate change. Added to gasoline, ethanol also reduces ground-level ozone formation by lowering volatile organic compound and hydrocarbon emissions, decreasing carcinogenic benzene, and butadiene, emissions, and particulate matter emissions from gasoline combustion. Since 90% of US crude oil reserves have been consumed, the US must import crude oil to meet energy demand. Substituting ethanol for gasoline would substantially reduces the foreign trade deficit, which is aggravated by crude oil [and gasoline] imports. [5]

Today, almost half of Brazilian cars are able to use 100% ethanol as fuel, which includes ethanol-only engines and flex-fuel engines. Flex-fuel engines [in Brazil] are able to work with all ethanol, all gasoline, or any mixture of both. In the US flex-fuel vehicles can run on zero% to 85% ethanol(15% gasoline) since higher ethanol blends are not yet allowed here.] Brazil supports this population of ethanol-burning automobiles with large national infrastructure that produces ethanol from domestically grown sugar cane. Sugar cane not only has a greater concentration of sucrose than corn (by about 30%), but is also much easier to extract. The bagasse generated by the process is not wasted, but is utilized in power plants as a surprisingly efficient fuel to produce electricity.

World production of ethanol in 2006 was 51 billion liters, (13.5 billion gallons), with 69% of the world supply coming from Brazil and the United States.[6]

The United States fuel ethanol industry is based largely on maize. According to the Renewable Fuels Association, as of October 30, 2007, 131 grain ethanol biorefineries in the United States have the capacity to produce 7.0 billion gallons of ethanol per year. An additional 72 construction projects underway (in the U.S.) can add 6.4 billion gallons of new capacity in the next 18 months. Over time, it is believed that a material portion of the ~150 billion gallon per year market for gasoline will begin to be replaced with fuel ethanol.[3]

The Energy Policy Act of 2005 requires that 4 billion gallons of "renewable fuel" be used in 2006 and this requirement will grow to a yearly production of 7.5 billion gallons by 2012.[4]

A Ford Taurus "fueled by clean burning ethanol" owned by New York City.

In the United States, ethanol is most commonly blended with gasoline as a 10% ethanol blend nicknamed "gasohol". This blend is widely sold throughout the U.S. Midwest, and in cities required by the 1990 Clean Air Act to oxygenate their gasoline during the winter.

Controversy

[edit]

As reported in "The Energy Balance of Corn Ethanol: an Update,"[7] the energy returned on energy invested EROEI for ethanol made from corn in the U.S. is 1.34 (it yields 34% more energy than it takes to produce it). Input energy includes natural gas based fertilizers, farm equipment, transformation from corn or other materials, and transportation. However, other researchers report that the production of ethanol consumes more energy than it yields.[8][9]

Lately criticism and controversy has been growing over the massive subsidies that some companies have been receiving for ethanol production,[10] including "the bulk of the more than $10 billion in subsidies to Archer-Daniels-Midland since 1980," according to the CATO institute.[11] Recent articles have also blamed subsidized ethanol production for the nearly 200% increase in milk prices since 2004,[12] although that is disputed by some.

Oil has historically had a much higher EROEI than agriculturally produced ethanol, especially from petroleum deposits accessible by land, but also from those that only offshore drilling rigs can reach. Apart from this, the amount of ethanol needed to run the United States, for example, is greater than its own farmland could produce, even if fields now used for food were converted for production of non-food-grade corn. It has been estimated that "if every bushel of U.S. corn, wheat, rice and soybean were used to produce ethanol, it would only cover about 4% of U.S. energy needs on a net basis."[13]

In the United States, preferential regulatory and tax treatment of ethanol automotive fuels introduces complexities beyond its energy economics alone. North American automakers have in 2006 and 2007 promoted a blend of 85% ethanol and 15% gasoline, marketed as E85, and their flex-fuel vehicles, e.g. GM's "Live Green, Go Yellow" campaign.[14] The apparent motivation is the nature of U.S. Corporate Average Fuel Economy (CAFE) standards, which give an effective 54% fuel efficiency bonus to vehicles capable of running on 85% alcohol blends over vehicles not adapted to run on 85% alcohol blends.[15] In addition to this auto manufacturer-driven impetus for 85% alcohol blends, the United States Environmental Protection Agency had authority to mandate that minimum proportions of oxygenates be added to automotive gasoline on regional and seasonal bases from 1992 until 2006 in an attempt to reduce air pollution, in particular ground-level ozone and smog.[16] As a consequence, much gasoline sold in the United States is blended with up to 10% of an unspecified oxygenating agent.[17] In America, incidents of methyl tert(iary)-butyl ether (MTBE) groundwater contamination in the majority of the 50 states,[18] and the State of California's ban on the use of MTBE as a gasoline additive has allowed ethanol to displace it as the most common fuel oxygenate.[19]

Controversy

[edit]

As reported in "The Energy Balance of Corn Ethanol: an Update,"[20] the energy returned on energy invested (EROEI) for ethanol made from corn in the U.S. is 1.34 (it yields 34% more energy than it takes to produce it). Input energy includes natural gas based fertilizers, farm equipment, transformation from corn or other materials, and transportation. However, other researchers report that the production of ethanol consumes more energy than it yields.[8][21] However, recent research suggests that cellulosic crops such as switchgrass provide a much better net energy production, producing over five times as much energy as the total used to produce the crop and convert it to fuel [22]. If this research is confirmed, cellulosic crops will probably displace corn as the main fuel crop for producing bioethanol, and existing calculations of potential will need a major revision.

Environmentalists, livestock farmers, and opponents of subsidies say that increased ethanol production won't meet energy goals and may damage the environment as food prices soar. Some of the controversial subsidies in the past have included more than $10 billion to Archer-Daniels-Midland since 1980.[23] Critics also speculate that as ethanol is more widely used, changing irrigation practices could greatly increase pressure on water resources. In October 2007, 28 environmental groups decried the Renewable Fuels Standard (RFS), a legislative effort intended to increase ethanol production, and said that the measure will "lead to substantial environmental damage and a system of biofuels production that will not benefit family farmers...will not promote sustainable agriculture and will not mitigate global climate change."[24][10] Recent articles have also blamed subsidized ethanol production for the nearly 200% increase in milk prices since 2004,[12] although that is disputed by some.

Oil has historically had a much higher EROEI than agriculturally produced ethanol, according to some. However, oil must be refined into gasoline before it can be used for automobile fuel. Refining, as well as exploration and drilling, consumes energy. The difference between the energy in the fuel (output energy) and the energy needed to produce it (input energy) is often expressed as a percent of the input energy and called net energy gain (or loss). Several studies released in 2002 estimated that the net energy gain for corn ethanol is between 21 and 34 percent. In comparison, gasoline production yields a net energy loss of between 19 and 20 percent. The net energy loss for MTBE is about 33 percent. When added to gasoline Ethanol can replace MBTE as an anti-knock agent without poisoning drinking water as MBTE does. Further agricultural practices and ethanol production improvements could lead to an increase in ethanol net energy gain in the future. Consuming known oil reserves is increasing oil exploration and drilling energy consumpyion which is reducing Oil EROEI (and energy balance) further. [25]

Some say the amount of ethanol needed to run the United States is greater than its own farmland could produce, even if fields now used for food were converted for production of non-food-grade corn. It has been estimated that "if every bushel of U.S. corn, wheat, rice and soybean were used to produce ethanol, it would only cover about 4% of U.S. energy needs on a net basis."[26] This ignores the fact that ethanol in the future will be produced from thrown away cellulose in the form of Biomass from forest products, switch grass, waste paper, and other material, technologies that are just getting underway today. [27] The calculation for how much gasoline can potentially be replaced by corn ethanol [excluding corn stover cellulose] is not that difficult. The US has 2,263 million acres of farmland. [28] The average corn yield is 140 bushels per acre [29] The ethanol yield from corn kernal distillation alone, excluding corn stover cellulosic ethanol, is 2.5 gallons per bushel. [30] This results in over 792 billion gallons of ethanol (multiplying the 3 items above) which is much over the 146 billion gallons per year of gasoline consumed each year in the US. [31] This doesn't even include cellulosic ethanol!

In the United States, preferential regulatory and tax treatment of ethanol automotive fuels introduces complexities beyond its energy economics alone. North American automakers have in 2006 and 2007 promoted a blend of 85% ethanol and 15% gasoline, marketed as E85, and their flex-fuel vehicles, e.g. GM's "Live Green, Go Yellow" campaign.[14] The apparent motivation is the nature of U.S. Corporate Average Fuel Economy (CAFE) standards, which give an effective 54% fuel efficiency bonus to vehicles capable of running on 85% alcohol blends over vehicles not adapted to run on 85% alcohol blends.[32] In addition to this auto manufacturer-driven impetus for 85% alcohol blends, the United States Environmental Protection Agency had authority to mandate that minimum proportions of oxygenates be added to automotive gasoline on regional and seasonal bases from 1992 until 2006 in an attempt to reduce air pollution, in particular ground-level ozone and smog.[33] In the United States, incidents of methyl tert(iary)-butyl ether (MTBE) groundwater contamination have been recorded in the majority of the 50 states,[34] and the State of California's ban on the use of MTBE as a gasoline additive has further driven the more widespread use of ethanol as the most common fuel oxygenate.[19]

References

[edit]
  1. ^ a b Reel, M. (August 19 2006) "Brazil's Road to Energy Independence" The Washington Post.
  2. ^ "Renewable Fuels Association Industry Statistics".
  3. ^ a b "First Commercial U.S. Cellulosic Ethanol Biorefinery Announced". Renewable Fuels Association. November 20, 2006. Retrieved 21 May 2006.
  4. ^ a b "Renewable Fuel Standard Program". United States Environmental Protection Agency. April 10, 2007. Retrieved 21 May 2007.
  5. ^ "Etnanol Fuel".
  6. ^ "Renewable Fuels Association Industry Statistics".
  7. ^ Hosein Shapouri, James A. Duffield, and Michael Wang. "The Energy Balance of Corn Ethanol: an Update" (PDF). United States Department of Agriculture. Retrieved 21 May 2007.{{cite web}}: CS1 maint: multiple names: authors list (link)
  8. ^ a b Pimentel D, Patzek TW (2005). "Ethanol Production Using Corn, Switchgrass, and Wood; Biodiesel Production Using Soybean and Sunflower". Natural Resources Research. 14 (1): 65–76. doi:10.1007/s11053-005-4679-8.
  9. ^ Lang, Susan S. "Cornell ecologist's study finds that producing ethanol and biodiesel from corn and other crops is not worth the energy". Cornell University. Retrieved 5 July 2005.
  10. ^ a b Moira Herbst (March 19, 2007). "Ethanol's Growing List of Enemies". Business Week. Retrieved 2007-09-03.
  11. ^ Doug Bandow (October 2, 1997). "Ethanol Keeps ADM Drunk On Tax Dollars". CATO Institute. Retrieved 2007-09-03.
  12. ^ a b Jeff Cox (June 19,2007). "Corn and milk: A 1-2 inflation combo". CNNMoney.com. Retrieved 2007-09-03. {{cite journal}}: Check date values in: |date= (help)
  13. ^ "Forget the Ethanol Myth -- Avoid Biofuel Bubble: John F. Wasik". Bloomberg.com. July 23, 2007. Retrieved 2007-07-25.
  14. ^ a b "GM Announces E85 Fuel Card Promotion On FlexFuel Vehicles". The Auto Channel. Retrieved 2007-09-04.
  15. ^ "CAFE Credits for Flex Fuel Vehicles Undermine Improvements in Fuel Economy". Public Citizen. 2006-09-27. Retrieved 2007-09-03. {{cite web}}: Check date values in: |date= (help)
  16. ^ "Regulations & Standards". United States Environmental Protection Agency. Retrieved 2007-09-04.
  17. ^ "Oxygenated Gasoline". Chevron Oil. Retrieved 2007-09-04.
  18. ^ "MTBE Contamination from Underground Storage Tanks" (PDF). United States General Accounting Office. May 21, 2002. Retrieved 2007-10-09.
  19. ^ a b "Methyl Tertiary Butyl Ether (MTBE)". United State Environmental Protection Agency. Retrieved 2007-09-04.
  20. ^ Hosein Shapouri, James A. Duffield, and Michael Wang. "The Energy Balance of Corn Ethanol: an Update" (PDF). United States Department of Agriculture. Retrieved 21 May 2007.{{cite web}}: CS1 maint: multiple names: authors list (link)
  21. ^ Lang, Susan S. "Cornell ecologist's study finds that producing ethanol and biodiesel from corn and other crops is not worth the energy". Cornell University. Retrieved 5 July 2005.
  22. ^ "Net energy of cellulosic ethanol from switchgrass".
  23. ^ Doug Bandow (October 2, 1997). "Ethanol Keeps ADM Drunk On Tax Dollars". CATO Institute. Retrieved 2007-09-03.
  24. ^ The Politics of Ethanol Outshine its Costs
  25. ^ David Andress & Associates (November, 2002
  26. ^ "Forget the Ethanol Myth -- Avoid Biofuel Bubble: John F. Wasik". Bloomberg.com. July 23, 2007. Retrieved 2007-07-25.
  27. ^ http://www.greencarcongress.com/cellulosic_ethanol/index.html. {{cite web}}: Missing or empty |title= (help)
  28. ^ http://www.ers.usda.gov/StateFacts/US.HTM)). {{cite web}}: Missing or empty |title= (help)
  29. ^ http://www.farmdoc.uiuc.edu/manage/newsletters/fefo06_08/fefo06_08.html). {{cite web}}: Missing or empty |title= (help)}
  30. ^ http://www.ethanol-gec.org/winter96/eawin9608.htm. {{cite web}}: Missing or empty |title= (help)). "Ethanol Energy Balances". {{cite web}}: Check date values in: |date= (help); External link in |date= (help); line feed character in |date= at position 22 (help)
  31. ^ http://auto.howstuffworks.com/question417.htm)). {{cite web}}: Missing or empty |title= (help)
  32. ^ "CAFE Credits for Flex Fuel Vehicles Undermine Improvements in Fuel Economy". Public Citizen. 2006-09-27. Retrieved 2007-09-03. {{cite web}}: Check date values in: |date= (help)
  33. ^ "Regulations & Standards". United States Environmental Protection Agency. Retrieved 2007-09-04.
  34. ^ "MTBE Contamination from Underground Storage Tanks" (PDF). United States General Accounting Office. May 21, 2002. Retrieved 2007-10-09.