Ethanol fuel
608623
226078111
2008-07-16T18:58:02Z
Arriva436
2363746
/* Europe */ Changed picture of bio-ethanol bus in Reading to an ethanol bus which has demonstrated in the whole UK.
{{renewable energy sources}}
[[Image:EthanolPetrol.jpg|right|thumb|Information on a pump in California.]]
'''Ethanol fuel''' is [[ethanol]] (ethyl alcohol), the same type of [[alcohol]] found in [[alcoholic beverages]]. It can be used as a fuel, mainly as a [[biofuel]] alternative to gasoline, and is widely used in cars in [[Ethanol fuel in Brazil|Brazil]]. Because it is easy to manufacture and process, and can be made from very common [[crops]], such as [[sugar cane]] and [[maize|maize (corn)]], it is an increasingly common alternative to [[gasoline]] in some parts of the world. Ethanol produced from cellulose is known as [[cellulosic ethanol]] or [[ceetol]].
'''Anhydrous ethanol''' (ethanol with less than 1% water) can be blended with gasoline in varying quantities up to pure [[ethanol]] ([[Common ethanol fuel mixtures#E100|E100]]), and most spark-ignited gasoline style engines will operate well with mixtures of 10% ethanol (E10).<ref>[http://www.esru.strath.ac.uk/EandE/Web_sites/02-03/biofuels/what_bioethanol.htm What is Bioethanol]</ref> Most cars on the road today in the U.S. can run on blends of up to 10% ethanol,<ref>Worldwatch Institute and Center for American Progress (2006). [http://images1.americanprogress.org/il80web20037/americanenergynow/AmericanEnergy.pdf ''American energy: The renewable path to energy security'']</ref> and the use of 10% ethanol gasoline is mandated in some cities where harmful levels of auto emissions are possible.<ref> [http://www.eia.doe.gov/pub/oil_gas/petroleum/data_publications/monthly_oxygenate_report/current/pdf/819mhilt.pdf EIA- 819 Monthly Oxygenate Report]</ref>
Ethanol can be mass-produced by fermentation of sugar or by hydration of [[ethylene]] (ethene CH<sub>2</sub>=CH<sub>2</sub>) from [[petroleum]] and other sources. Current interest in ethanol mainly lies in bio-ethanol, produced from the [[starch]] or [[sugar]] in a wide variety of crops, but there has been considerable debate about how useful bio-ethanol will be in replacing fossil fuels in vehicles. Concerns relate to the large amount of arable land required for crops,<ref> [http://www.efrc.com/manage/authincludes/article_uploads/Deforestation%20diesel1.pdf Deforestation diesel – the madness of biofuel]</ref> as well as the energy and pollution balance of the whole cycle of ethanol production.<ref>Youngquist, W. Geodestinies, National Book company, Portland, OR, 499p.</ref><ref>[http://www.oilcrash.com/articles/pf_bio.htm The dirty truth about biofuels]</ref> Recent developments with [[cellulosic ethanol commercialization|cellulosic ethanol production and commercialization]] may allay some of these concerns.<ref>[http://news.bbc.co.uk/2/hi/science/nature/5353118.stm Biofuels look to the next generation]</ref>
According to the [[International Energy Agency]], [[cellulosic ethanol]] could allow ethanol fuels to play a much bigger role in the future than previously thought.<ref>International Energy Agency (2006). [http://www.worldenergyoutlook.org/summaries2006/English.pdf ''World Energy Outlook 2006''] p. 8.</ref> Cellulosic ethanol offers promise as resistant cellulose fibers, a major component in plant cells walls, can be used to generate ethanol. Dedicated energy crops, such as [[switchgrass]], are also promising cellulose sources that can be produced in many regions of the United States.<ref>Biotechnology Industry Organization (2007). [http://bio.org/ind/biofuel/CellulosicEthanolIssueBrief.pdf ''Industrial Biotechnology Is Revolutionizing the Production of Ethanol Transportation Fuel''] pp. 3-4.</ref>
==Chemistry==
[[Image:Ethanol-3d-stick-structure.svg|thumb|In this 3-d diagram of ethanol, the lines represent [[single bond]]s.]]
Glucose is created in the plant by [[photosynthesis]].
: 6CO<sub>2</sub> + 6H<sub>2</sub>O + light → C<sub>6</sub>H<sub>12</sub>O<sub>6</sub> + 6O<sub>2</sub>
During [[ethanol fermentation]], [[glucose]] is decomposed into [[ethanol]] and [[carbon dioxide]].
:C<sub>6</sub>H<sub>12</sub>O<sub>6</sub> → 2C<sub>2</sub>H<sub>6</sub>O + 2CO<sub>2</sub> + heat
During combustion ethanol reacts with [[oxygen]] to produce carbon dioxide, [[water]], and heat:
:C<sub>2</sub>H<sub>6</sub>O + 3O<sub>2</sub> → 2CO<sub>2</sub> + 3H<sub>2</sub>O + heat
After doubling the ethanol combustion reaction because two molecules of ethanol are produced for each glucose molecule, there are equal numbers of each type of molecule on each side of the equation, and the net reaction for the overall production and consumption of ethanol is just:
:light → heat
The heat of the combustion of ethanol is used to to drive the piston in the engine by expanding heated gases. It can be said that sunlight is used to run the engine.
Air pollutants are also produced when ethanol is burned in the [[atmosphere]] rather than in pure oxygen. Harmful nitrous oxide gases are produced. Nitrogen dioxide is one of the harmful gases as is a major contributor to the formation of "brown smog".{{Fact|date=May 2008}}
==Sources==
{{Main|Energy crop}}
[[Image:Saccharum-officinarum-harvest.JPG|thumb|Sugar cane harvest]]
[[Image:Cornfield in South Africa2.jpg|thumb|Cornfield in [[South Africa]]]]
[[Image:Panicum virgatum.jpg|thumb|upright|[[Switchgrass]]]]
Ethanol is considered "[[renewable energy|renewable]]" because it is primarily the result of conversion of the [[sun]]'s energy into usable energy. Creation of ethanol starts with [[photosynthesis]] causing the feedstocks such as [[switchgrass]], [[sugar cane]], or [[corn]] to grow. These feedstocks are processed into ethanol.
About 5% of the ethanol produced in the world in 2003 was actually a petroleum product.<ref> [http://www.meti.go.jp/report/downloadfiles/g30819b40j.pdf meti.go.jp file g30819b40j]</ref> It is made by the catalytic hydration of ethylene with [[sulfuric acid]] as the [[catalyst]]. It can also be obtained via [[ethylene]] or [[acetylene]], from [[calcium carbide]], [[coal]], oil gas, and other sources. Two million tons of petroleum-derived ethanol are produced annually. The principal suppliers are plants in the United States, Europe, and South Africa.<ref> [http://www.grainscouncil.com/Policy/Biofuels/Qld_Biofuels_study.pdf#search=%22%22synthetic%20ethanol%22%20producer%22 (grainscouncil.com, Biofuels_study 268 kB pdf, footnote, p 6)]</ref> Petroleum derived ethanol (synthetic ethanol) is chemically identical to bio-ethanol and can be differentiated only by radiocarbon dating.<ref> [http://www.ethanolproducer.com/article-print.jsp?article_id=2077 ethanolproducer.com, article 2077]</ref>
Bio-ethanol is obtained from the conversion of carbon based feedstock. Agricultural feedstocks are considered renewable because they get energy from the [[sun]] using [[photosynthesis]], provided that all minerals required for growth (such as nitrogen and phosphorus) are returned to the land. Ethanol can be produced from a variety of feedstocks such as [[sugar cane]], [[bagasse]], [[miscanthus]], [[sugar beet]], [[sorghum]], grain [[sorghum]], [[switchgrass]], [[barley]], [[hemp]], [[kenaf]], [[potato]]es, [[sweet potato]]es, [[cassava]], [[sunflower]], [[fruit]], [[molasses]], [[corn]], [[stover]], [[grain]], [[wheat]], [[straw]], [[cotton]], other [[biomass]], as well as many types of [[cellulose]] waste and harvestings, whichever has the best [[well-to-wheel]] assessment.
Current, first generation processes for the production of ethanol from corn use only a small part of the corn plant: the corn kernels are taken from the corn plant and only the starch, which represents about 50% of the dry kernel mass, is transformed into ethanol. Two types of second generation processes are under development. The first type uses [[enzyme]]s and [[yeast]] to convert the plant cellulose into ethanol while the second type uses [[pyrolysis]] to convert the whole plant to either a liquid [[bio-oil]] or a [[syngas]]. Second generation processes can also be used with plants such as grasses, wood or agricultural waste material such as straw.
====Production process====
{{see also|Corn ethanol#Problems associated with corn-derived ethanol|l1=problems associated with corn-derived ethanol}}
The basic steps for large scale production of ethanol are: microbial ([[yeast]]) [[Fermentation (biochemistry)|fermentation]] of sugars, [[distillation]], [[dehydration]] (requirements vary, see Ethanol fuel mixtures, below), and [[denatured alcohol|denaturing]] (optional). Prior to fermentation, some crops require [[saccharification]] or [[hydrolysis]] of carbohydrates such as cellulose and starch into sugars. Saccharification of cellulose is called [[cellulolysis]] (see [[cellulosic ethanol]]). Enzymes are used to convert starch into sugar.<ref>{{cite web
| url= http://www.greencarcongress.com/2005/06/new_enzyme_for_.html
| title= New Enzyme for More Efficient Corn Ethanol Production
| date= 2005-06-30 |publisher= Green Car Congress
| accessdate= 2008-01-14 }} </ref>
====Fermentation====
{{Main|Ethanol fermentation}}
Ethanol is produced by [[microbial fermentation]] of the sugar. Microbial fermentation will currently only work directly with [[sugar]]s. Two major components of plants, [[starch]] and [[cellulose]], are both made up of sugars, and can in principle be converted to sugars for fermentation. Currently, only the sugar (e.g. sugar cane) and starch (e.g. corn) portions can be economically converted. However, there is much activity in the area of [[cellulosic ethanol]], where the cellulose part of a plant is broken down to sugars and subsequently converted to ethanol.
====Distillation====
[[Image:Ethanol plant.jpg|thumb|right|Ethanol plant in West [[Burlington, Iowa]] ]]
[[Image:UsinaSantaElisa.jpg|thumb|right|Ethanol plant in Sertãozinho, Brazil.]]
For the ethanol to be usable as a fuel, water must be removed. Most of the water is removed by [[distillation]], but the purity is limited to 95-96% due to the formation of a low-boiling water-ethanol [[azeotrope]]. The 95.6% m/m (96.5% v/v) ethanol, 4.4% m/m (3.5% v/v) water mixture may be used as a fuel alone, but unlike [[anhydrous]] ethanol, is immiscible in gasoline, so the water fraction is typically removed in further treatment in order to burn with in combination with gasoline in gasoline engines.
====Dehydration====
There are basically three dehydration processes to remove the water from an [[azeotropic]] ethanol/water mixture. The first process, used in many early fuel ethanol plants, is called [[azeotropic distillation]], and consists of adding [[benzene]] or [[cyclohexane]] to the mixture. When these components are added to the mixture, it forms an heterogeneous azeotropic mixture in [[vapor-liquid-liquid equilibrium]], which, when distillated, produces anhydrous ethanol in the column bottom, and a vapor mixture of water and cyclohexane/benzene, which when condensed becomes a two-phase liquid mixture. Another early method, called [[extractive distillation]], consists of adding a ternary component which will increase ethanol relative volatility. When the ternary mixture is distillated, it will produce anhydrous ethanol on the top stream of the column.
With increasing attention being paid to saving energy, many methods have been proposed that avoid distillation all together for dehydration. Of these methods, a third method has emerged and has been adopted by the majority of modern ethanol plants. This new process uses [[molecular sieves]] to remove water from fuel ethanol. In this process, ethanol vapor under pressure passes through a bed of molecular sieve beads. The bead's pores are sized to allow absorption of water while excluding ethanol. After a period of time, the bed is regenerated under vacuum to remove the absorbed water. Two beds are used so that one is available to absorb water while the other is being regenerated. This dehydration technology can account for energy saving of 3,000 btus/gallon compared to earlier azeotropic distillation. [http://www.bioethanol.ru/images/bioethanol/Fuel%20ethanol%20production%20-%20Katzen.pdf Modern Corn Ethanol plant description]
==Technology==
===Ethanol-based engines===
Ethanol is most commonly used to power automobiles, though it may be used to power other vehicles, such as [[farm tractor]]s and [[airplanes]]. Ethanol (E100) consumption in an engine is approximately 34% higher than that of gasoline (the energy per volume unit is 34% lower).<ref name=EEREFAQ /><ref name=EIAATTF /><!-- 404 <ref name=FUELECON />--> However, higher [[compression ratio]]s in an ethanol-only engine allow for increased power output and better fuel economy than would be obtained with the lower compression ratio.<ref> [http://courses.washington.edu/me341/oct22v2.htm washington.edu, course, October 22 v2]</ref><ref> [http://www.swri.edu/4org/d03/engres/spkeng/sprkign/pbeffimp.htm Efficiency Improvements Associated with Ethanol-Fueled Spark-Ignition Engines]</ref> In general, ethanol-only engines are tuned to give slightly better power and torque output to gasoline-powered engines. In flexible fuel vehicles, the lower compression ratio requires tunings that give the same output when using either gasoline or hydrated ethanol. For maximum use of ethanol's benefits, a much higher compression ratio should be used,<ref>{{cite web
| url= http://web.mit.edu/newsoffice/2006/engine.html
| title= "MIT's pint-sized car engine promises high efficiency, low cost"
| author= Nancy Stauffer | date= 2006-10-25 |work=
| publisher= [[Massachusetts Institute of Technology]]
| accessdate= 2008-01-14 }} </ref> which would render that engine unsuitable for gasoline use. When ethanol fuel availability allows high-compression ethanol-only vehicles to be practical, the fuel efficiency of such engines should be equal or greater than current gasoline engines. However, since the energy content (by volume) of ethanol fuel is less than gasoline, a larger volume of ethanol fuel (151%) would still be required to produce the same amount of energy.<ref> [http://www.hybridcars.com/component/option,com_joomblog/Itemid,0/joomblog_task,blog_view/joomblog_contentid,12019/ Squeezing More Out of Ethanol]</ref>
A 2004 MIT study,<ref> [http://www.psfc.mit.edu/library1/catalog/reports/2000/06ja/06ja016/06ja016_full.pdf MIT Study] </ref> and an earlier paper published by the Society of Automotive Engineers,<ref> [http://www.sae.org/technical/papers/2000-01-2902 SAE Paper 2001-01-2901]</ref> describing tests, identify a method to exploit the characteristics of fuel ethanol that is substantially better than mixing it with gasoline. The method presents the possibility of leveraging the use of alcohol to even achieve definite improvement over the cost-effectiveness of hybrid electric. The improvement consists of using dual-fuel direct-injection of pure alcohol (or the azeotrope or E85) and gasoline, in any ratio up to 100% of either, in a turbocharged, high compression-ratio, small-displacement engine having performance similar to an engine having twice the displacement. Each fuel is carried separately, with a much smaller tank for alcohol. The high-compression (which increases efficiency) engine will run on ordinary gasoline under low-power cruise conditions. Alcohol is directly injected into the cylinders (and the gasoline injection simultaneously reduced) only when necessary to suppress ‘knock’ such as when significantly accelerating. Direct cylinder injection raises the already high octane rating of ethanol up to an effective 130. The calculated over-all reduction of gasoline use and CO2 emission is 30%. The consumer cost payback time shows a 4:1 improvement over turbo-diesel and a 5:1 improvement over hybrid. In addition, the problems of water absorption into pre-mixed gasoline (causing phase separation), supply issues of multiple mix ratios and cold-weather starting are avoided.
Ethanol's higher octane rating allows an increase of an engine's compression ratio for increased [[thermal efficiency]].<ref>[http://courses.washington.edu/me341/oct22v2.htm washington.edu, course, October 22 v2]</ref> In one study, complex engine controls and increased exhaust gas recirculation allowed a compression ratio of 19.5 with fuels ranging from neat ethanol to E50. Thermal efficiency up to approximately that for a diesel was achieved.<ref>{{cite web
| url= http://www.epa.gov/otaq/presentations/epa-fev-isaf-no55.pdf
| title= Economical, High-Efficiency Engine Technologies for Alcohol Fuels
| author= Matthew Brusstar | coauthors= Marco Bakenhus
|date= |year= |month= |work=
| format= [[PDF]] | publisher= [[U. S. Environmental Protection Agency]]
| accessdate= 2008-01-14 }} </ref> This would result in the MPG (miles per gallon) of a dedicated ethanol vehicle to be about the same as one burning gasoline.
Engines using fuel with 30% to 100% ethanol also need a cold-starting system. For E85 fuel at temperatures below 11 °C (52 °F) a cold-starting system is required for reliable starting and to meet EPA emissions standards.<ref>{{cite web
| url= http://www.michigan.gov/documents/CIS_EO_coldstart_AF-E-62_87914_7.pdf
| title= Project: Development of Technologies to Improve Cold Start Performance of Ethanol Vehicles
|author= Gregory W. Davis
|date= 2001-06-11 |format= [[PDF]] |work= |publisher= STATE OF MICHIGAN Department of Consumer & Industry Services
| accessdate= 2008-01-14 }} </ref> However, the EPA does not require cold start systems on E85 vehicles. No current production E85 vehicles in the USA are equipped with these cold start systems, and they meet EPA emission guidelines.{{Fact|date=May 2008}}
===Ethanol fuel mixtures===
{{see details|Common ethanol fuel mixtures}}
[[Image:gas x álcool - 70%.svg|thumb|upright|right|Hydrated ethanol × [[gasoline type C]] price table for use in Brazil]]
To avoid engine stall due to "slugs" of water in the fuel lines interrupting fuel flow, the fuel must exist as a single phase. The fraction of water that an ethanol-gasoline fuel can contain without phase separation increases with the percentage of ethanol.<ref>This is shown for 25°C (77°F) in a gasoline-ethanol-water phase diagram, Fig 13 of {{cite web
| url= http://virtual.vtt.fi/inf/julkaisut/muut/2004/EtOH_VTT5100_03.pdf
| title= Technical View on Biofuels for Transportation – Focus on Ethanol End-Use Aspects
|author= Päivi Aakko |coauthors= Nils-Olof Nylund
|date= |year= |month= |format= [[PDF]] |work= |publisher=
| accessdate= 2008-01-14 }}
</ref>. This shows, for example, that E30 can have up to about 2% water. If there is more than about 71% ethanol, the remainder can be any proportion of water or gasoline and phase separation will not occur. However, the fuel mileage declines with increased water content. The increased solubility of water with higher ethanol content permits E30 and hydrated ethanol to be put in the same tank since any combination of them always results in a single phase. Somewhat less water is tolerated at lower temperatures. For E10 it is about 0.5% v/v at 70 F and decreases to about 0.23% v/v at -30 F.<ref>as shown in Figure 1 of http://www.epa.gov/OMS/regs/fuels/rfg/waterphs.pdf </ref>
In many countries cars are mandated to run on mixtures of ethanol. Brazil requires cars be suitable for a 25% ethanol blend, and has required various mixtures between 22% and 25% ethanol, since of July 2007 25% is required. The United States allows up to 10% blends, and some states require this (or a smaller amount) in all gasoline sold. Other countries have adopted their own requirements.
Beginning with the model year 1999, an increasing number of vehicles in the world are manufactured with engines which can run on any fuel from 0% ethanol up to 100% ethanol without modification. Many cars and [[light truck]]s (a class containing [[minivan]]s, [[sport utility vehicle|SUV]]s and [[pickup truck]]s) are designed to be [[flexible-fuel vehicle]]s (also called ''dual-fuel'' vehicles). In older model years, their engine systems contained alcohol sensors in the fuel and/or oxygen sensors in the exhaust that provide input to the engine control computer to adjust the fuel injection to achieve [[stochiometric]] (no residual fuel or free oxygen in the exhaust) air-to-fuel ratio for any fuel mix. In newer models, the alcohol sensors have been removed, with the computer using only oxygen and airflow sensor feedback to estimate alcohol content. The engine control computer can also adjust (advance) the ignition timing to achieve a higher output without pre-ignition when it predicts that higher alcohol percentages are present in the fuel being burned. This method is backed up by advanced knock sensors - used in most high performance gasoline engines regardless of whether they're designed to use ethanol or not - that detect pre-ignition and detonation.
===Fuel economy===
In theory, all fuel-driven vehicles have a [[fuel economy]] (measured as miles per US gallon, or liters per 100 km) that is directly proportional to the fuel's energy content.<ref>www.eia.doe.gov [http://www.eia.doe.gov/cneaf/alternate/page/faq.html#12 DOE FAQ]</ref>In reality, there are many other variables that come in to play that affect the performance of a particular fuel in a particular engine. Ethanol contains approx. 34% less energy per unit volume than gasoline, and therefore in theory, burning pure ethanol in a vehicle will result in a 34% reduction in miles per US gallon, given the same fuel economy, compared to burning pure gasoline. This assumes that the octane ratings of the fuels, and thus the engine's ability to extract energy from the fuels, are the same.<ref name=EEREFAQ>www.eere.energy.gov [http://www.eere.energy.gov/afdc/progs/ddown.cgi?afdc/FAQ/5/0/0 Energy.gov site]</ref><ref name=EIAATTF>www.eia.doe.gov [http://www.eia.doe.gov/cneaf/solar.renewables/alt_trans_fuel/attf.pdf#page=39 Alternative Fuel Efficiencies in Miles per Gallon]</ref><!-- 404 <ref name=FUELECON />--> For E10 (10% ethanol and 90% gasoline), the effect is small (~3%) when compared to conventional gasoline,<ref>www.raa.net [http://www.raa.net/page.asp?TerID=146|RAA All About Cars - Ethanol in Petrol] February 2004. Royal Automobile Association of South Australia. Retrieved on [[2007]]-[[04-29]]</ref> and even smaller (1-2%) when compared to oxygenated and reformulated blends.<ref> http://www.epa.gov [http://www.epa.gov/orcdizux/rfgecon.htm EPA Info]</ref> However, for [[E85]] (85% ethanol), the effect becomes significant. E85 will produce lower mileage than gasoline, and will require more frequent refueling. Actual performance may vary depending on the vehicle. The EPA-rated mileage of current USA flex-fuel vehicles<ref> http://www.fueleconomy.gov [http://www.fueleconomy.gov/feg/byfueltype.htm EPA Mileage]</ref> should be considered when making price comparisons, but it must be noted that E85 is a high performance fuel, with an octane rating of about 104, and should be compared to premium. In one estimate<ref name=bourne/> the US [[retail price]] for E85 ethanol is 2.62 [[US dollar]] per [[gallon]] or 3.71 dollar corrected for energy equivalency compared to a gallon of gasoline priced at 3.03 dollar. Brazilian cane ethanol (100%)is priced at 3.88 dollar against 4.91 dollar for E25 (figures July 2007).
==Experience by country==
The top five ethanol producers in 2006 were the United States with 4.855 billion [[gallon|U.S. liquid gallons]] (bg), Brazil (4.49 bg), China (1.02 bg), India (0.50 bg) and France (0.25 bg).<ref name="RFA1E">{{cite web|url=http://www.ethanolrfa.org/industry/statistics/#E|title=Industry Statistics: Annual World Ethanol Production by Country|publisher=Renewable Fuels Association|date= |accessdate=2008-05-02|language= }}</ref> Brazil and the United States accounted for 70 percent of all ethanol production, with total world production of 13.5 billion US gallons (40 million tonnes). When accounting just for fuel ethanol production in 2007, the U.S. and Brazil are responsible for 88% of the 13.1 billion gallons total world production. Strong incentives, coupled with other industry development initiatives, are giving rise to fledgling ethanol industries in countries such as [[Thailand]], [[Colombia]], and some [[Central America]]n countries. Nevertheless, ethanol has yet to make a dent in world oil consumption of approximately 4000 million tonnes/yr (84 million barrels/day).<ref> [http://www.ethanolproducer.com/article.jsp?article_id=2222 It's a global thing], ''Ethanol Producer Magazine'', August 2006.</ref>
{| class="wikitable" style="margin: 1em auto 1em auto"
! colspan="5" align=center style="background-color: #abcdef;" | Total Annual Ethanol Production (All Grades)<br/>by Country (2004-2006)<ref name="RFA1E"/> <br /> Top 15 countries <br /><small>(Millions of [[gallon|U.S. liquid gallons]])</small> || colspan="3" align=center style="background-color: #abcdef;" | Annual Fuel Ethanol Production<br/> by Country (2004-2006)<ref name="RFA08">{{cite web|url=http://www.ethanolrfa.org/objects/pdf/outlook/RFA_Outlook_2008.pdf |title=Changing the Climate: Ethanol Industry Outlook 2008 |publisher=Renewable Fuels Association |accessdate=2008-05-10|language= }} Source:F.O. Licht</ref> <br /> Top 15 countries/blocks <br /><small>(Millions of [[gallon|U.S. liquid gallons]])</small>
|- align=center
| bgcolor="#ABCDEF"| World <br /> rank|| bgcolor="#ABCDEF"|Country|| bgcolor="#ABCDEF"|2006|| bgcolor="#ABCDEF"|2005|| bgcolor="#ABCDEF"|2004 ||bgcolor="#ABCDEF"| World <br /> rank|| bgcolor="#ABCDEF"|Country/Region|| bgcolor="#ABCDEF"|2007
|-
|align="center"|1||{{USA}}||align="center"|4,855 || align="center"|4,264 || align="center"|3,535 ||align="center"|1||{{USA}}||align="center"|6,498.6
|-
|align="center"|2||{{BRA}}||align="center"|4,491 ||align="center"|4,227 ||align="center"|3,989 ||align="center"|2||{{BRA}}||align="center"|5,019.2
|-
|align="center"|3||{{CHN}}||align="center"|1,017 ||align="center"|1,004 ||align="center"|964 ||align="center"|3||{{EU}}||align="center"|570.3
|-
|align="center"|4||{{IND}}||align="center"|502 ||align="center"|449 ||align="center"|462 ||align="center"|4 ||{{CHN}} || align="center"|486.0
|-
|align="center"|5||{{FRA}}||align="center"|251 ||align="center"|240 ||align="center"|219 ||align="center"|5||{{CAN}}||align="center"|211.3
|-
|align="center"|6||{{GER}} ||align="center"|202 ||align="center"|114 ||align="center"|71 ||align="center"|6||{{THA}}||align="center"|79.2
|-
|align="center"|7||{{RUS}}||align="center"|171 ||align="center"|198 ||align="center"|198 ||align="center"|7||{{COL}}||align="center"|74.9
|-
|align="center"|8||{{CAN}} ||align="center"|153 ||align="center"|61 ||align="center"|61 || align="center"|8||{{IND}}||align="center"|52.8
|-
|align="center"|9||{{ESP}}||align="center"|122 ||align="center"|93 ||align="center"|79 ||align="center"|9||[[Central America]]||align="center"|39.6
|-
|align="center"|10||{{flag|South Africa}}||align="center"|102 ||align="center"|103 ||align="center"|110 ||align="center"|10||{{AUS}}||align="center"|26.4
|-
|align="center"|11||{{THA}} ||align="center"|93 ||align="center"|79 ||align="center"|74 || align="center"|11||{{TUR}}||align="center"|15.8
|-
|align="center"|12||{{UK}}||align="center"|74 ||align="center"|92 ||align="center"|106 || align="center"|12||{{PAK}}||align="center"|9.2
|-
|align="center"|13||{{flag|Ukraine}} ||align="center"|71 ||align="center"|65 ||align="center"|66 || align="center"|13||{{PER}}||align="center"|7.9
|-
|align="center"|14||{{POL}} ||align="center"|66 ||align="center"|58 ||align="center"|53 || align="center"|14||{{ARG}}||align="center"|5.2
|-
|align="center"|15||{{flag|Saudi Arabia}} ||align="center"|52 ||align="center"|32 ||align="center"|79 ||align="center"|15||{{PAR}}||align="center"|4.7
|-
| bgcolor="#ABCDEF"| || align="center" bgcolor="#ABCDEF"| World Total ||align="center" bgcolor="#ABCDEF"|13,489 ||align="center" bgcolor="#ABCDEF"|12,150 ||align="center" bgcolor="#ABCDEF"|10,770 ||bgcolor="#ABCDEF"| || align="center" bgcolor="#ABCDEF"|World Total||align="center" bgcolor="#ABCDEF"|13,101.7
|}
===Brazil===
{{Main|Ethanol fuel in Brazil}}
[[Image:Sao Paulo ethanol pump 04 2008 74 zoom.jpg|200px|thumb|right|[[Brazil]] has ethanol fuel available throughout the country. A typical [[Petrobras]] [[filling]] station at [[São Paulo]] with dual fuel service, marked A for alcohol (ethanol) and G for [[gasoline]].]]
[[Image:Four Brazilian full flex-fuel automoviles 05 2008.jpg|200px|thumb|right|Typical [[Brazil]]ian [[flexible-fuel vehicle|"flex" models]] from several car makers, that run on any blend of [[ethanol (fuel)|ethanol]] and [[gasoline]].]]
[[Brazil]] has the largest and most successful bio-fuel programs in the world, involving production of ethanol fuel from [[sugar cane]], and it is considered to have the world's first [[sustainable]] [[biofuel]]s economy.<ref name="Wilson">{{cite web|url=http://www.wilsoncenter.org/topics/pubs/Brazil_SR_e3.pdf|title=Brazil Institute Special Report: The Global Dynamics of Biofuels|author=Daniel Budny and Paulo Sotero, editor|publisher=Brazil Institute of the Woodrow Wilson Center|date= 2007-04|accessdate=2008-05-03|language=}}</ref><ref name="Apollo">{{Citation | last = Inslee, Jay; Bracken Hendricks | title = Apollo's Fire | year = 2007 | pages=153-155, 160-161 | publisher = Island Press, Washington, D.C. | id = ISBN 978-1-59726-175-3 . ''See Chapter 6. Homegrown Energy.''}}</ref><ref name="NYT100406">{{cite web|url=http://www.nytimes.com/2006/04/10/world/americas/10brazil.html?pagewanted=1&sq=Bush%20Brazil%20ethanol&st=nyt&scp=5 |title=With Big Boost From Sugar Cane, Brazil Is Satisfying Its Fuel Needs |author=Larry Rother|publisher=The New York Times|date=2006-04-10|accessdate=2008-04-28|language= }}</ref> In 2006 Brazilian [[ethanol]] provided around 20% of the country's road transport sector fuel consumption needs, and more than 40% of fuel consumption for the light vehicle fleet.<ref name= "BEN2007">{{cite web|url=http://www.mme.gov.br/site/menu/select_main_menu_item.do?channelId=1432&pageId=14493 |title=2007 Brazilian Energy Balance: Executive Summary |author= | |date=|publisher=Ministério de Minas e Energia do Brasil |accessdate=2008-05-10|language=English}} Table 2. Report is based in 2006 data</ref><ref name= "Brazil48_20">{{cite web|url=http://www.washingtontimes.com/article/20080507/COMMENTARY/381443705/1012/commentary |title=Brazil's energy plan examined |author=D. Sean Shurtleff | |date=2008-05-07|publisher=The Washington Times |accessdate=2008-05-10|language=}}</ref>
<ref name="Apollo"/> As a result of the increasing use of ethanol, together with the exploitation of domestic deep water oil sources, Brazil, which years ago had to import a large share of the petroleum needed for domestic consumption, in 2006 reached complete self-sufficiency in oil supply.<ref> [http://www.renewableenergyaccess.com/rea/news/story?id=44896 America and Brazil Intersect on Ethanol] ''Renewable Energy Access'', 15 May 2006. </ref><ref> [http://cesp.stanford.edu/news/oil_addiction_20060417/ How to manage our oil addiction - CESP]</ref><ref> [http://www.washingtonpost.com/wp-dyn/content/article/2006/04/21/AR2006042100139.html New Rig Brings Brazil Oil Self-Sufficiency] ''Washington Post'', 21 April 2006.</ref>
Together, [[Brazil]] and the [[United States]] lead the industrial world in global [[ethanol]] production, accounting together for 70% of the world's production<ref name="WasPos1">{{cite web |url=http://www.washingtonpost.com/wp-dyn/content/article/2007/02/22/AR2007022201361.html |title=Latin America -- the 'Persian Gulf' of Biofuels? |publisher=The Washington Post|author= Marcela Sanchez |date=2007-02-23 |accessdate=2008-05-03|language= }}</ref> and nearly 90% of ethanol used for fuel. <ref name="WorldBank">{{cite web|url=http://siteresources.worldbank.org/INTWDR2008/Resources/2795087-1192112387976/WDR08_05_Focus_B.pdf |title=Biofuels: The Promise and the Risks, in World Development Report 2008 |publisher=The Worl Bank|date=2008|pages= pp. 70-71|accessdate=2008-05-04|language= }}</ref> In 2006 Brazil produced 16.3 billion [[liter]]s (4.3 billion [[gallon|U.S. liquid gallons]]),<ref name="RFA1E">{{cite web |url=http://www.ethanolrfa.org/industry/statistics/#E|title=Industry Statistics: Annual World Ethanol Production by Country|publisher=Renewable Fuels Association|date= |accessdate=2008-05-02|language= }}</ref> which represents 33.3% of the world's total ethanol production and 42% of the world's ethanol used as fuel.<ref name="WorldBank"/> Sugar cane plantations cover 3.6 million [[hectares]] of land for ethanol production, representing just 1% of Brazil's arable land, with a productivity of 7,500 liters of ethanol per hectare, as compared with the U.S. [[maize]] ethanol productivity of 3,000 liters per hectare.<ref name="Veja_30_04">{{Cite web|url=http://veja.abril.com.br/300408/p_058.shtml|title=Ele é o falso vilão|author=Julia Duailibi|publisher=Veja Magazine|language=Portuguese|date=2008-04-27|accessdate=2008-05-03}}</ref><ref name="Wilson"/>
Production and use of ethanol has been stimulated through:
:*Low-interest loans for the construction of ethanol distilleries
:*Guaranteed purchase of ethanol by the state-owned oil company at a reasonable price
:*Retail pricing of neat ethanol so it is competitive if not slightly favorable to the gasoline-ethanol blend
:*Tax incentives provided during the 1980s to stimulate the purchase of neat ethanol vehicles.<ref name="aceee"> American Council for an Energy-Efficient Economy (1999). [http://www.aceee.org/store/proddetail.cfm?CFID=2968430&CFTOKEN=11214103&ItemID=90&CategoryID=7 ''Policies for a More Sustainable Energy Future'']</ref>
Guaranteed purchase and price regulation were ended some years ago, with relatively positive results. In addition to these other policies, ethanol producers in the state of São Paulo established a research and technology transfer center that has been effective in improving sugar cane and ethanol yields.<ref name="aceee"/>
There are no longer light vehicles in Brazil running on pure gasoline. Since 1977 the government made mandatory to blend 20% of ethanol ([[E20]]) with [[gasoline]] ([[gasohol]]), requiring just a minor adjustment on regular gasoline motors. Today the mandatory blend is allowed to vary nationwide between 20% to 25% ethanol ([[Common ethanol fuel mixtures|E25]]) and it is used by all regular gasoline vehicles, plus three million cars running on 100% anhydrous ethanol and five million of [[w:Flexible-fuel_vehicle#Flexible-fuel_vehicles_in_Brazil\|dual or flexible-fuel vehicles]]. The Brazilian car manufacturing industry developed full flexible-fuel vehicles that can run on any proportion of gasoline and ethanol.<ref name="CEPAL">{{cite web |url=http://www.agrocombustibles.org/conceptos/CepalBiocombustiblesLac2004.pdf| title=Perspectivas de un Programa de Biocombustibles en América Central: Proyecto Uso Sustentable de Hidrocarburos|author=Luiz A. Horta Nogueira|publisher=Comisión Económica para América Latina y el Caribe (CEPAL)|date=2004-03-22|accessdate=2008-05-09|language=Spanish}}</ref> Introduced in the market in 2003, these vehicles became a commercial success.<ref name="ICIS">{{cite web| url=http://www.icis.com/Articles/2007/11/12/9077311/brazils-flex-fuel-car-production-rises-boosting-ethanol-consumption-to-record-highs.html |title=Brazil's flex-fuel car production rises, boosting ethanol consumption to record highs|date=2007-11-12|author=William Lemos |publisher=ICIS chemical business |accessdate=2008-05-03|language= }}</ref> On March 2008, the fleet of "flex" cars and light commercial vehicles had reached 5 million new vehicles sold.<ref name= "Globo1">{{cite web|url=http://g1.globo.com/Noticias/Carros/0,,MUL345131-9658,00-BRASIL+TEM+MILHOES+DE+VEICULOS+BICOMBUSTIVEIS.html |title=Brasil tem 5 milhões de veículos bicombustíveis |date=2008-03-10|publisher=Globo G1|accessdate=2008-05-04|language=Portuguese}}</ref> which represents around 10% of Brazil's motor vehicle fleet and 15.6% of all light vehicles.<ref>{{cite web|url=http://www2.cidades.gov.br/renaest/detalheNoticia.do?noticia.codigo=120|publisher=Departamento Nacional de Trânsito |language=Portuguese|title=DENATRAN Frota por tipo/UF 2008 (file 2008-03) |accessdate=2008-05-03}} As of March 31st, 2008, DENATRAN reports a total fleet of 50 million, including motorcycles, trucks and special equipment, and 32 million automobiles and light commercial vehicles.</ref> The ethanol-powered and [[flexible-fuel vehicle|"flex" vehicles]], as they are popularly known, are manufactured to tolerate hydrated ethanol, an [[azeotrope]] comprised of 95.6% ethanol and 4.4% water.<ref name="Ethanol">{{Citation | last = Goettemoeller, Jeffrey; Adrian Goettemoeller | title = Sustainable Ethanol: Biofuels, Biorefineries, Cellulosic Biomass, Flex-Fuel Vehicles, and Sustainable Farming for Energy Independence | year = 2007| publisher = Praire Oak Publishing, Maryville, Missouri |pages=42 |language=| id = ISBN 978-0-9786293-0-4 }}</ref>
The first vehicle in the world,{{Fact|date=June 2008}} moved by pure ethanol, was the [[Fiat 147]], built in July 1979.{{Fact|date=June 2008}} In the late 1988, ethanol vehicles held almost 90% of the Brazilian‘s market, but an strong crisis in ethanol supplies in early 1990 left thousands of vehicles out of fuel in their garages, and makes the ethanol vehicles production fall to less than 20% of the total fuel produced in one year. Recently, in early 2003, Volkswagen started the production of the [[Volkswagen Gol]] Total Flex, the first full flexible-fuel vehicle, that supports any percentage of ethanol and gasoline used as fuel. Because of the flexible-fuel vehicles, the ethanol production in 2006, reached more than 60% of the total fuel production in 2006.{{Fact|date=June 2008}}
===United States===
{| class="wikitable" style="float: right; margin-left: 10px"
! colspan="4" align=center style="background-color: #ccffcc;" | {{U.S.}} fuel ethanol <br/>production and imports <br/> (2001-2007)<ref name="RFA1E"/><br /><small>(Millions of [[gallon|U.S. liquid gallons]])</small>
|-
! style="background-color: #ccffcc;" | Year
! style="background-color: #ccffcc;" | Production
! style="background-color: #ccffcc;" | Imports
! style="background-color: #ccffcc;" | Demand
|-----
| align="right" | 2001 || align="right" | 1,770|| align="right" | n/a || align="right" | n/a
|-----
| align="right" | 2002 || align="right" | 2,130|| align="right" | 46 || align="right" | 2,085
|-----
| align="right" | 2003 || align="right" | 2,800|| align="right" | 61 || align="right" | 2,900
|-----
| align="right" | 2004 || align="right" | 3,400|| align="right" | 161 || align="right" | 3,530
|-----
| align="right" | 2005 || align="right" | 3,904|| align="right" | 135 || align="right" | 4,049
|-----
| align="right" | 2006 || align="right" | 4,855|| align="right" | 653 || align="right" | 5,377
|-----
| align="right" | 2007 || align="right" | 6,485|| align="right" | 435 || align="right" | 6,847
|-----
| colspan="4" align=left |<small>Note: Demand figures includes stocks change<br/> and small exports in 2005</small>
|}
{{Main|Ethanol fuel in the United States}}
The United States produces and consumes more ethanol fuel than any other country in the world. Most cars on the road today in the U.S. can run on blends of up to 10% ethanol, and motor vehicle manufacturers already produce vehicles designed to run on much higher ethanol blends. In 2007 Portland, Oregon, became the first city in the United States to require all gasoline sold within city limits to contain at least 10% ethanol.<ref>{{cite web
| url= http://postcarboncities.net/node/192
| title= In biodiesel we trust
|author= Todd Murphy
|date= 2007-05-22 |work= |publisher= ''[[Portland Tribune]]''
| accessdate= 2008-01-14 }} </ref><ref> [http://www.cleanedge.com/book/Introduction_The_Clean_Tech_Revolution.pdf Introduction: The Clean Tech Opportunity] p. 3.</ref> As of January 2008, three states — Missouri, Minnesota, and Hawaii — require ethanol to be blended with gasoline motor fuel. Many cities are also required to use an ethanol blend due to non-attainment of federal air quality goals.<ref>3 states, many cities: [http://www.npr.org/templates/story/story.php?storyId=17720583]</ref>
[[Image:Ethanol Car.jpg|thumb|left|A [[Ford Taurus]] "fueled by clean burning ethanol" owned by [[New York City]].]]
Several motor vehicle manufacturers, including [[Ford Motor Company|Ford]], [[DaimlerChrysler]], and [[General Motors Corporation|GM]], sell [[flexible-fuel vehicle]]s that can use gasoline and ethanol blends ranging from pure gasoline all the way up to 85% ethanol (E85). By mid-2006, there were approximately six million E85-compatible vehicles on U.S. roads.<ref> [http://images1.americanprogress.org/il80web20037/americanenergynow/AmericanEnergy.pdf American energy: The renewable path to energy security]</ref>
In the USA there are currently 1,587 stations distributing ethanol, although most stations are in the [[corn belt]] area.<ref name="EUBIA"> [http://www.eubia.org/fileadmin/template/main/res/pdf/Projects/Brochure5_Bioethanol_low_res.pdf Brochure5_Bioethanol_low_res Bioethanol Production and Use] “Creating Markets for Renewable Energy Technologies EU, RES Technology Marketing Campaign“, [[European Biomass Industry Association]] EUBIA 4/2007, page 12</ref><ref name="nevc">[http://www.e85refueling.com/ National Ethanol Vehicle Coalition]</ref> One of the debated methods for distribution in the US is using existing [[oil pipeline]]s,<ref>{{cite web
| url= http://www.planetark.com/dailynewsstory.cfm/newsid/46173/story.htm
| title= US Ethanol Producers Covet Existing Oil Pipelines
|author= Timothy Gardner
|date= 2007-12-24 |work= |publisher= [[Reuters]]
| accessdate= 2008-01-14 }} </ref> which raises concerns over corrosion. In any case, some companies proposed building a 1,700-mile pipeline to carry ethanol from the [[Midwest]] through Central [[Pennsylvania]] to [[New York]]. <ref>http://correu.cs.san.gva.es/exchweb/bin/redir.asp?URL=http://www.pennenvironment.org/in-the-news/energy/energy/new-3b-ethanol-pipeline-could-run-through-midstate</ref>
The production of fuel ethanol from corn in the United States is controversial for a few reasons. Production of ethanol from corn is 5 to 6 times less efficient than producing it from sugarcane. Ethanol production from corn is highly dependent upon subsidies and it consumes a food crop to produce fuel.<ref name=bourne/> The subsidies paid to fuel blenders and ethanol refineries have often been cited as the reason for driving up the price of corn, and in farmers planting more corn and the conversion of considerable land to corn (maize) production which generally consumes more fertilizers and pesticides than many other land uses.<ref name=bourne/> This is at odds with the subsidies actually paid directly to farmers that are designed to take corn land out of production and pay farmers to plant grass and idle the land, often in conjunction with soil conservation programs, in an attempt to boost corn prices. Recent developments with [[cellulosic ethanol commercialization| cellulosic ethanol production and commercialization]] may allay some of these concerns. A theoretically much more efficient way of ethanol production has been suggested to use sugar beets which make about the same amount of ethanol as corn without using the corn food crop especially since sugar beats can grow in less tropical conditions than sugar cane.[http://news.bbc.co.uk/2/hi/science/nature/5353118.stm Biofuels look to the next generation] </ref>
===Europe===
{| class="wikitable" style="float: right; margin-left: 10px"
! colspan="4" align=center style="background-color: #ddf;" | Production of [[Bioethanol]] in the <br/>{{EU}} (GWh)<ref name="BaroBiofuels2007"> [http://www.energies-renouvelables.org/observ-er/stat_baro/erec/baro179_b.asp Biofuels barometer 2007 - EurObserv’ER] Systèmes solaires Le journal des énergies renouvelables n° 179, s. 63-75, 5/2007</ref>
|-
! style="background-color: #ddf;" | No
! style="background-color: #ddf;" | Country
! style="background-color: #ddf;" | 2006
! style="background-color: #ddf;" | 2005
|-----
| align="right" | 1 || align=left | {{GER}} || align="right" | 2,554 || align="right" | 978
|-----
| align="right" | 2 || align=left | {{ESP}} || align="right" | 2,382 || align="right" | 1,796
|-----
| align="right" | 3 || align=left | {{FRA}} || align="right" | 1,482 || align="right" | 853
|-----
| align="right" | 4 || align=left | {{SWE}} || align="right" | 830|| align="right" | 907
|-----
| align="right" | 5 || align=left | {{ITA}} || align="right" | 759|| align="right" | 47
|-----
| align="right" | 6 || align=left | {{POL}} || align="right" | 711 || align="right" | 379
|-----
| align="right" | 7 || align=left | {{HUN}} || align="right" | 201 || align="right" | 207
|-----
| align="right" | 8 || align=left | {{LIT}} || align="right" | 107 || align="right" | 47
|-----
| align="right" | 9 || align=left | {{NED}} || align="right" | 89 || align="right" | 47
|-----
| align="right" | 10 || align=left | {{CZE}} || align="right" | 89 || align="right" | 0
|-----
| align="right" | 11 || align=left | {{LAT}} || align="right" | 71 || align="right" | 71
|-----
| align="right" | 12 || align=left | {{FIN}} || align="right" | 0 || align="right" | 77
|-----
| align="right" style="background-color: #ddf;" | '''27''' || align=left style="background-color: #ddf;" | '''Total '''
| align="right" style="background-color: #ddf;" | '''9,274''' || align="right" style="background-color: #ddf;" | '''5,411'''
|-----
| colspan="4" align=left | <small>100 l bioethanol = 79,62 kg, <BR/>1 tonne bioethanol = 0,64 toe
</small>
|}
{| class="wikitable" style="float: right; background-color::#efefef; margin-left: 10px"
! colspan="4" align="left" style="background-color: #ddf;" | Consumption of [[Bioethanol]] in the <br/>{{EU}} (GWh)<ref name="BaroBiofuels2007"> [http://www.energies-renouvelables.org/observ-er/stat_baro/erec/baro179_b.asp Biofuels barometer 2007 - EurObserv’ER] Systèmes solaires Le journal des énergies renouvelables n° 179, s. 63-75, 5/2007</ref>
|-
! style="background-color: #ddf;" | No
! style="background-color: #ddf;" | Country
! style="background-color: #ddf;" colspan=1 align="left" | 2006
! style="background-color: #ddf;" colspan=1 align= "left" | 2005
|-----
| align="right" | 1 || align="left" | {{GER}} || align="right" | 3,573 || align="right" | 1,682
|-----
| align="right" | 2 || align="left" | {{SWE}} || align="right" | 1,895 || align="right" | 1,681
|-----
| align="right"| 3 || align="left" | {{FRA}} || align="right" | 1,747|| align="right" | 871
|-----
| align="right" | 4 || align="left" | {{ESP}} || align="right" | 1,332 || align="right" | 1,314
|-----
| align="right" | 5 || align="left" | {{POL}} || align="right" | 611 || align="right" | 329
|-----
| align="right" | 6 || align="left" | {{UK}} || align="right" | 561 || align="right" | 502
|-----
| align="right" | 7 || align="left" | {{NED}} || align="right" | 238 || align="right" | 0
|-----
| align="right" | 8 || align="left" | {{HUN}} || align="right" | 125 || align="right" | 28
|-----
| align="right" | 9 || align="left" | {{LIT}} || align="right" | 99 || align="right" | 10
|-----
| align="right" | 10 || align="left" | {{CZE}} || align="right" | 14 || align="right" | 0
|-----
| align="right" | 11 || align="left" | {{FIN}}|| align="right" | 9 || align="right" | 0
|-----
| align="right" | 12 || align="left" | {{IRL}} || align="right" | 8 || align="right" | 0
|-----
| align="right" | 13 || align="left" | {{ITA}} || align="right" | 0 || align="right" | 59
|-----
| align="right" | 14 || align="left" | {{LAT}} || align="right" | 0 || align="right" | 5
|-----
! align="right" style="background-color: #ddf;" | 27 || align=left style="background-color: #ddf;" | EU
| align="right" style="background-color: #ddf;" | '''10,210''' || align="right" style="background-color: #ddf;" | '''6,481'''
|-----
| colspan=4 align=left | <small> 1 toe = 11,63 MWh </small>
|}
The consumption of bioethanol is largest in Europe in Germany, Sweden, France and Spain. Europe produces equivalent to 90% of its consumption (2006). Germany produced ca 70% of its consumption, Spain 60% and Sweden 50% (2006). In Sweden there are 792 E85 filling stations and in France 131 [[E85]] service stations with 550 more under construction.<ref name=EUBIA/>
On Monday, [[September 17]], [[2007]] the first ethanol fuel pump was opened in Reykjavik, [[Iceland]]. This pump is the only one of its kind in Iceland. The fuel is imported by Brimborg, a Volvo dealer, as a pilot to see how ethanol fueled cars work in Iceland. In a few weeks, the pump will be opened for public use.{{Fact|date=October 2007}}
In [[The Netherlands]] regular petrol with no bio-additives is slowly outphased, since EU-legislation has been passed that requires the fraction of nonmineral origin to become minimum 5,75% of the total fuel consumption volume in 2010. This can be realised by substitutions in diesel or in petrol of any biological source; or fuel sold in the form of pure biofuel. (2007:) There are only a few gas stations where E85 is sold, which is an 85% ethanol, 15% petrol mix.<ref>[http://www.biotanken.nl/website/zoektanklocatie.php Biofuel gas stations locator]</ref> Directly neighbouring country Germany is reported to have a much better biofuel infrastructure and offers both E85 and E50. Biofuel is taxed equally as regular fuel. However, fuel tanked abroad cannot be taxed and a recent payment receipt will in most cases suffice to prevent fines if customs check tank contents. (Authorities are aware of high taxation on fuels and cross-border fuel refilling is a well-known practice.)
[[Image:Scania OmniCity ethanol demonstrator.JPG|right|thumb|200px|An example of an ethanol powered bus. This is a [[Scania OmniCity]] which has been touring the United Kingdom, which does not use the fuel widely. A larger fleet of similar buses will enter service in Stockholm in 2008.]]
{{Main|Ethanol fuel in Sweden}}
All [[Sweden|Swedish]] gas stations are required by an act of parliament to offer at least one [[alternative fuel]], and every fifth car in Stockholm now drives at least partially on alternative fuels, mostly ethanol.<ref>[http://www.progressive.org/mag_johansen0707 Scandinavia Gets Serious on Global Warming], ''The Progressive'', July 2007.</ref> The number of bioethanol stations in Europe is highest in Sweden, with 792 stations.
Stockholm will introduce a fleet of Swedish-made electric hybrid buses in its public transport system on a trial basis in 2008. These buses will use ethanol-powered internal-combustion engines and electric motors. The vehicles’ diesel engines will use ethanol.<ref>[http://www.progressive.org/mag_johansen0707 Scandinavia Gets Serious on Global Warming], ''The Progressive'', July 2007.</ref>
{| class="wikitable" align="center"
! colspan="3" align="center" style="background-color: #F3D161;" | Bioethanol stations <br/>{{EU}}<ref name="EUBIA"> [http://www.eubia.org/fileadmin/template/main/res/pdf/Projects/Brochure5_Bioethanol_low_res.pdf Bioethanol Production and Use, Creating Markets for Renewable Energy Technologies], [[European Biomass Industry Association]] EUBIA 4/2007, page 12</ref>
|-
! style="background-color: #F3D161;" align=center | Country
! style="background-color: #F3D161;" align=center | Stations
! style="background-color: #F3D161;" align=center | No/10<sup>6</sup><BR/>persons
|-----
| align="left" | {{SWE}}|| align="right" | 792 || align="right" | 86.6
|-----
| align="left" | {{GER}}|| align="right" | 73 || align="right" | 0.89
|-----
| align="left" | {{FRA}} || align="right" | 36 || align="right" | 0.56
|-----
| align="left" | {{UK}} || align="right" |14 || align="right" | 0.24
|-----
| align="left" | {{IRL}} || align="right" | 13 || align="right" | 3.07
|-----
| align="left" | {{SWI}} || align="right" | 6 || align="right" | 0.8
|-----
|}
===Asia===
====China====
[[China]] is promoting ethanol-based fuel on a pilot basis in five cities in its central and northeastern region, a move designed to create a new market for its surplus grain and reduce consumption of petroleum. The cities include Zhengzhou, Luoyang and Nanyang in central China's [[Henan province]], and Harbin and Zhaodong in [[Heilongjiang province]], northeast China. Under the program, Henan will promote ethanol-based fuel across the province by the end of this year. Officials say the move is of great importance in helping to stabilize grain prices, raise farmers' income and reducing petrol- induced air pollution.<ref>[http://english.people.com.cn/200206/17/eng20020617_98009.shtml China Promotes Ethanol-Based Fuel in Five Cities]</ref>
====Thailand====
[[Thailand]] already use 10% ethanol ([[E10]]) widely on big scale on the local market. Beginning in 2008 Thailand started with the sale of [[E20]] and the in the third quarter of 2008 [[E85]] will come on the mark.
===Australia===
{{Main|Ethanol fuel in Australia}}
Legislation in [[Australia]] imposes a 10% cap on the concentration of fuel ethanol blends. Blends of 90% unleaded petrol and 10% fuel ethanol are commonly referred to as E10. E10 is available through service stations operating under the BP, Caltex, Shell and United brands as well as those of a number of smaller independents. Not surprisingly, E10 is most widely available closer to the sources of production in Queensland and New South Wales. E10 is most commonly blended with 91 RON "regular unleaded" fuel. There is a requirement that retailers label blends containing fuel ethanol on the [[fuel dispenser|dispenser]].
===Caribbean Basin===
{| class="wikitable" style="float: right; margin-left: 10px"
! colspan="7" align=center style="background-color: #ccffcc;" | {{U.S.}} fuel ethanol <br/>imports by country<br/> (2002-2007)<ref name="RFA1E"/><br /><small>(Millions of [[gallon|U.S. liquid gallons]])</small>
|-
! style="background-color: #ccffcc;" | Country
! style="background-color: #ccffcc;" | 2007*
! style="background-color: #ccffcc;" | 2006
! style="background-color: #ccffcc;" | 2005
! style="background-color: #ccffcc;" | 2004
! style="background-color: #ccffcc;" | 2003
! style="background-color: #ccffcc;" | 2002
|-----
| align="left" | {{BRA}} || align="right" | 188.8|| align="right" | 433.7|| align="right" | 31.2 || align="right" | 90.3|| align="right" |0 || align="right" | 0
|-----
| align="left" | {{JAM}} || align="right" | 75.2|| align="right" | 66.8 || align="right" | 36.3|| align="right" | 36.6|| align="right" | 39.3|| align="right" | 29.0
|-----
| align="left" | {{ESA}} || align="right" | 73.3|| align="right" | 38.5 || align="right" | 23.7|| align="right" | 5.7|| align="right" | 6.9|| align="right" | 4.5
|-----
| align="left" | {{flag|Trinidad and Tobago}} || align="right" | 42.7|| align="right" | 24.8 || align="right" | 10.0|| align="right" | 0|| align="right" | 0|| align="right" | 0
|-----
| align="left" | {{CRI}} || align="right" | 39.3|| align="right" | 35.9|| align="right" | 33.4|| align="right" | 25.4|| align="right" | 14.7|| align="right" | 12.0
|-----
| colspan="7" align=left |<small>*Note: 2007 figures through November only.</small>
|}
All countries in [[Central America]], northern [[South America]] and the [[Caribbean]] are located in a tropical zone with suitable climate for growing [[sugar cane]]. In fact, most of these countries have a long tradition of growing sugar cane mainly for producing [[sugar]] and [[alcoholic beverage]]s.
As a result of the [[guerilla]] movements in Central America, in 1983 the United States [[unilateral]] and temporarily approved the [[Caribbean Basin Initiative]], allowing most countries in the region to benefit from several tariff and trade benefits. These benefits were made permanent in 1990 and more recently, these benefits were replaced by the [[Caribbean Basin Trade and Partnership Act]], approved in 2000, and the [[Dominican Republic–Central America Free Trade Agreement]] that went to effect in 2008. All these agreements have allowed several countries in the region to export ethanol to the U.S free of tariffs.<ref name="CEPAL"/> Until 2004, the countries that benefited the most were [[Jamaica]] and [[Costa Rica]], but as the U.S. began demanding more fuel ethanol, the two countries increased their exports and two others began exporting. In 2007, [[Jamaica]], [[El Salvador]], [[Trinidad & Tobago]] and [[Costa Rica]] exported together to the U.S. a total of 230.5 million gallons of ethanol, representing 54.1% of U.S. fuel ethanol imports. [[Brasil]] began exporting ethanol to the U.S. in 2004 and exported 188.8 million gallons representing 44.3% of U.S. ethanol imports in 2007. The remaining imports that year came from [[Canada]] and [[China]].<ref name="RFA1E"/>
In March 2007, "ethanol diplomacy" was the focus of President [[George W. Bush]]'s Latin American tour, in which he and Brazil's president, [[Luiz Inacio Lula da Silva]], were seeking to promote the production and use of sugar cane based ethanol throughout [[Latin America]] and the [[Caribbean]]. The two countries also agreed to share technology and set international standards for biofuels.<ref name="WasPos1"/> The Brazilian sugar cane technology transfer would allow several [[Central American]], [[Caribbean]] and [[Andean Community of Nations|Andean]] countries to take advantage of their tariff-free trade agreements to increase or become exporters to the United States in the short-term.<ref>{{cite web |url=http://www.nytimes.com/2007/03/03/business/worldbusiness/03ethanol.html?scp=1&sq=Bush+Brazil+ethanol&st=nyt |title=U.S. and Brazil Seek to Promote Ethanol in West |publisher=The New York Times| author= Edmund L. Andrews and Larry Rother|date=2007-03-03 |accessdate=2008-04-28|language= }}</ref> Also, in August 2007, Brazil's President toured [[Mexico]] and several countries in Central America and the Caribbean to promote Brazilian ethanol technology.<ref>{{cite web |url=http://www.nacion.com/ln_ee/2007/agosto/10/ultima-sr1199181.html |title=Diplomacia de biocombustibles" de Lula no genera entusiasmo |publisher=La Nación | author= Diana Renée |date=2007-08-10 |accessdate=2008-04-28|language=Spanish}}</ref> The ethanol alliance between the U.S. and Brazil generated some negative reactions from [[Venezuela]]'s President [[Hugo Chavez]],<ref>{{cite web |url=http://www.nytimes.com/2007/03/10/world/americas/10prexy.html?scp=1&sq=Bush+Brazil+ethanol+Chavez&st=nyt |title=Bush and Chávez Spar at Distance Over Latin Visit |publisher= The Washington Post | author= Jim Rutenberg and Larry Rohter|date=2007-03-10 |accessdate=2008-04-28|language= }}</ref> and by then [[Cuba]]'s President, [[Fidel Castro]], who wrote that "''you will see how many people among the hungry masses of our planet will no longer consume corn''." "''Or even worse''," he continued, "''by offering financing to poor countries to produce ethanol from corn or any other kind of food, no tree will be left to defend humanity from climate change''."'<ref>{{cite web |url=http://query.nytimes.com/gst/fullpage.html?res=9A07E1DE1130F933A05750C0A9619C8B63 |title=Americas: Cuba: Castro Criticizes U.S. Biofuel Policies |publisher=The New York Times|author= |date=2007-03-30 |accessdate=2008-04-28|language= }}</ref> [[Daniel Ortega]], [[Nicaragua]]'s President, and one of the preferencial recipients of Brazilian technical aid also voiced critics to the Bush plan, but he vowed support for sugar cane based ethanol during [[Luiz Inacio Lula da Silva|Lula]]'s visit to Nicaragua.<ref>{{cite web |url=http://english.peopledaily.com.cn/90001/90777/6235427.html |title=Nicaragua president backs sugar-made biofuel as Lula visits |publisher=People's Daily Online |author=Xinhua News |date=2007-08-09 |accessdate=2008-04-28|language= }}</ref><ref>{{cite web |url=http://www.nacion.com/ln_ee/2007/agosto/09/economia1197405.html |title=Lula ofrece cooperación y energía eléctrica |publisher=La Nación |author=AFP |date=2007-08-09 |accessdate=2008-04-28|language=Spanish }}</ref>
==== Colombia ====
[[Colombia]]'s ethanol program began in 2002, based on a law approved in 2001 mandating a mix of 10% ethanol with regular gasoline. Sugar cane-based ethanol production began in 2005, and as local production was not enough to supply enough ethanol to the entire country's fleet, the program was implemented only on cities with more than 500,000 inhabitants, such as [[Cali]], [[Pereira]], and the capital city of [[Bogotá]]. All of the ethanol production comes from the [[Department of Valle del Cauca]], Colombia's traditional sugar cane region.
<!--
El programa para etanol como combustible de Colombia comenzó en [[2002]] año en que el gobierno aprobó una ley que obligaba al [[enriquecimiento en oxígeno]] de la gasolina. Esto se hizo inicialmente para reducir las emisiones de [[monóxido de carbono]] de los coches. Regulaciones más recientes eximieron al etanol elaborado a partir de [[biomasa]] de algunos impuestos que gravan la gasolina, haciendo así más barato el etanol que la gasolina. Esta tendencia se vio reforzada cuando los precios del petróleo subieron a principios de [[2004]] y con él el interés en combustibles renovables (al menos para los coches). En Colombia el precio de la gasolina y del etanol es controlado por el gobierno. Complementariamente a este programa para el etanol existe un programa para el biodiesel para oxigenar combustible diésel y para producir un combustible renovable a partir del aceite vegetal.
Al principio todo el interés en la producción del etanol venía de la industria de azúcar existente, ya que es relativamente fácil añadir un módulo para desarrollar etanol al final de una fabrica de azúcar y las necesidades energéticas son similares a las que se necesitarían para producir el azúcar. El gobierno alienta a convertir gradualmente las fuentes de combustible de los coches a una mezcla del 10 por ciento de etanol y de 90 por ciento de gasolina. Las plantas del etanol están siendo incentivadas por tratos fiscales. Ha habido interés en plantas de etanol de [[yuca]] (mandioca) y de nuevas plantaciones de la caña de azúcar, pero aún no se ha conseguido producir carbohidratos a bajo precio.
La primera planta de etanol (para usarlo como combustible) en Colombia comenzó a producir en octubre de 2005, con la salida de 300.000 litros al día en [[Cauca (departamento)|Cauca]]. Hasta marzo de 2006 cinco plantas, todas en el valle del Río Cauca (departamentos de Valle, Cauca y Risaralda), están operativas con una capacidad combinada de 1.050.000 litros por día o de 357 millones de litros por año. En el Valle del Cauca el azúcar se cosecha durante todo el año y las destilerías nuevas tienen una disponibilidad muy alta. La inversión total en estas plantas es $100 millones. Eventualmente, Colombia espera tener una capacidad de 2.500.000 litros por el día, que es el la cantidad necesaria para agregar el 10% de etanol a la gasolina. El etanol producido se utiliza actualmente en las principales ciudades cerca del Valle del Cauca, tal como [[Cali]] y [[Pereira]], como también en la capital, [[Bogotá]]. No hay suficiente producción para el resto del país.
-->
====Costa Rica====
Starting in October 2008, all gasoline sold in [[Costa Rica]] will be blended with 7.5% ethanol. This follows a two year trial that took place in the provinces of [[Guanacaste]] and [[Puntarenas]]. The government expects to increase the percent of ethanol mixed with gasoline to 12% in the next 4 to 5 years. The Costa Rican government is pursuing this policy to lower the country's dependency of foreign oil and to reduce the amount of greenhouse gases produced. The plan also calls for an increase in ethanol producing crops and tax breaks for flex-fuel vehicles.<ref>{{cite web |url=http://www.nacion.com/ln_ee/2008/mayo/25/pais1549119.html |title=Gasolineras solo venderán biocombustible desde octubre |publisher=La Nación |author=Vanessa Loaiza N. |date=2008-05-25 |accessdate=2008-06-07|language=Spanish }}</ref>
====El Salvador====
As a result of the cooperation agreement between the United States and Brazil, [[El Salvador]] was chosen in 2007 to lead a pilot experience to introduce state-of-the-art technology for growing sugar cane for production of ethanol fuel in [[Central America]], as this technical bilateral cooperation is looking for helping Central American countries to reduce their dependence on foreign oil.<ref>{{cite web |url=http://www.nacion.com/ln_ee/2008/mayo/29/economia1556986.html|title=Centroamérica busca cooperación de Brasil para biocombustibles y comercio |publisher=La Nación |author=Oscar Batres |date=2008-05-29 |accessdate=2008-06-07|language=Spanish }}</ref>
<!--
Brief description of the main producers/exporters from Central America will be done later. Feel free to edit. The CEPAL paper already referenced has enough info.
====Guatemala====
-->
===Comparison between Brazil and the U.S.===
Brazil's sugar cane-based industry is far more efficient than the U.S. corn-based industry. Brazilian distillers are able to produce ethanol for 22 cents per liter, compared with the 30 cents per liter for corn-based ethanol.<ref>''The Economist'', March 3-9th, 2007 "Fuel for Friendship" p. 44</ref> Sugarcane cultivation requires a tropical or subtropical climate, with a minimum of 600 mm (24 in) of annual rainfall. Sugarcane is one of the most efficient photosynthesizers in the plant kingdom, able to convert up to 2% of incident solar energy into biomass. Ethanol is produced by yeast fermentation of the sugar extracted from sugar cane.
Sugarcane production in the United States occurs in [[Florida]], [[Louisiana]], [[Hawaii]], and [[Texas]]. In prime growing regions, such as Hawaii, sugarcane can produce 20 kg for each square meter exposed to the sun. The first three plants to produce sugar cane-based ethanol are expected to go online in Louisiana by mid 2009. Sugar mill plants in [[Lacassine, Lousiana|Lacassine]], [[St. James Parish, Louisiana|St. James]] and [[Bunkie, Louisiana|Bunkie]] were converted to sugar cane-based ethanol production using [[Colombia]]n technology in order to make possible a profitable ethanol production. These three plants will produce 100 million gallons of ethanol within five years.<ref>{{cite web|url=http://www.miamiherald.com/news/americas/story/562380.html|publisher=Miami Herald|author=Gerardo Reyes|title=Colombians in U.S. sugar mills to produce ethanol|date=2008-06-08|accessdate=2008-06-11|language=}}</ref>
U.S. corn-derived ethanol costs 30% more because the corn starch must first be converted to sugar before being distilled into alcohol. Unfortunately, despite this cost differential in production, in contrast to [[Japan]] and [[Sweden]], the U.S. does not import much of Brazilian ethanol because of U.S. trade barriers corresponding to a [[tariff]] of 54-cent per gallon – a levy designed to offset the 51-cent per gallon blender's federal tax credit that is applied to ethanol no matter its country of origin.<ref>[http://www.renewableenergyaccess.com/rea/news/story?id=46863 U.S. Congress Stands Behind Domestic Ethanol, Extends Tariff<!-- Bot generated title -->]</ref> One advantage U.S. corn-derived ethanol offers is the ability to return 1/3 of the feedstock back into the market as a replacement for the corn used in the form of Distillers Dried Grain.<ref name="Ethanol"/>
{| class="wikitable" style="margin: 1em auto 1em auto"
! colspan="4" align=center style="background-color: #abcdef;" | Comparison of key characteristics between <br /> the ethanol industries in the United States and Brazil
|- align=center
| bgcolor="#ABCDEF"| Characteristic|| bgcolor="#ABCDEF"| {{BRA}} || bgcolor="#ABCDEF"|{{flag|U.S.}} || bgcolor="#ABCDEF"| Units/comments
|-
|Feedstock ||align="center"| Sugar cane ||align="center" | Maize || <small>Main [[cash crop]] for ethanol production, the US has less than 2% from other crops.</small>
|-
|Total ethanol production (2007) <ref name="RFA1E"/>||align="center"| 5,019.2 ||align="center"|6,498.6 || <small>Million [[gallon|U.S. liquid gallons]] </small>
|-
|Total arable land <ref name="Veja_30_04">{{Cite web|url=http://veja.abril.com.br/300408/p_058.shtml|title=Ele é o falso vilão|author=Julia Duailibi|publisher=Veja Magazine|language=Portuguese|date=2008-04-27|accessdate=2008-05-03}}</ref>||align="center"| 355 ||align="center"| 270<small><sup>(1)</sup><small> || <small>Million [[hectares]]. </small>
|-
|Total area used for ethanol crop <ref name="Veja_30_04"/><ref name="Ethanol">{{Citation | last = Goettemoeller, Jeffrey; Adrian Goettemoeller | title = Sustainable Ethanol: Biofuels, Biorefineries, Cellulosic Biomass, Flex-Fuel Vehicles, and Sustainable Farming for Energy Independence | year = 2007| publisher = Praire Oak Publishing, Maryville, Missouri |pages=42 |language=| id = ISBN 978-0-9786293-0-4 }}</ref> ||align="center"| 3.6 <small>(1%)</small>||align="center"| 10 <small>(3.7%)</small>|| <small>Million [[hectares]] (% total arable) </small>
|-
|Productivity per hectare <ref name="Veja_30_04"/><ref name="Wilson"/><ref name="Ethanol"/>||align="center"| 7,500 ||align="center"| 4,000 || <small>[[Liter]]s of ethanol per [[hectare]]. Brazil is 727 to 870 gal/acre (2006), US is 424 gal/acre (2006)</small>
|-
|Energy balance (input energy productivity) <ref name="NYT100406"/><ref name="Ethanol"/><ref name= "MLA_2004">{{cite web|url=http://www.eners.ch/plateforme/medias/macedo_2004.pdf |author= Macedo Isaias, M. Lima Verde Leal and J. Azevedo Ramos da Silva|title= Assessment of greenhouse gas emissions in the production and use of fuel ethanol in Brazil|publisher=Secretariat of the Environment, Government of the State of São Paulo|date=2004|accessdate=2008-05-09|language=}}</ref>||align="center"| 8.3 to 10.2 times ||align="center"| 1.3 to 1.6 times||<small>Ratio of the energy obtained from ethanol to the energy expended in its production</small>
|-
|Estimated [[greenhouse gas emission]] reduction <ref name="WorldBank"/><ref name="Ethanol"/><ref name= "Science07">{{cite web|url=http://www.sciencemag.org/cgi/content/abstract/1151861|title=Use of U.S. Croplands for Biofuels Increases Greenhouse Gases Through Emissions from Land-Use Change|author=Timothy Searchinger et al.|publisher=Science Express |date=2008-02-07|accessdate=2008-05-09|language=}}</ref> ||align="center"| 86-90%<small><sup>(2)</sup><small>||align="center"| 10-30%<small><sup>(2)</sup><small>||<small> % GHGs avoided by using ethanol instead of gasoline, using existing crop land.</small>
|-
|Ethanol fueling stations in the counrty<ref name="Wilson"/><ref name="Apollo"/>||align="center"| 33,000 <small>(100%)</small>||align="center"| 873 <small>(0,5%)</small>||<small>As % of total fueling gas stations in the country. U.S. has 170,000 (see Inslee, op cit pp. 161)</small>
|-
|Fuel ethanol used by the road transport sector <ref name= "Brazil48_20"/><ref name= "BEN2007"/> ||align="center"| 20%<small><sup>(3)</sup><small> ||align="center"| 3.6% ||<small>As % of the sector's total on a volumetric basis for 2006. </small>
|-
|Cost of production ([[USD]]/[[gallon]]) <ref name="Wilson"/> ||align="center"| 0.83||align="center"| 1.14|| <small>2006/2007 for Brazil (22¢/liter), 2004 for U.S. (35¢/liter) </small>
|-
|Government subsidy (in [[USD]]) <ref name="Veja_30_04"/><ref name="Apollo"/>||align="center"| 0||align="center"| 0.51/gallon || <small>U.S. as of [[2008-04-30]]. Brazilian ethanol production is no longer subsidized. </small>
|-
|Import tariffs (in [[USD]]) <ref name="NYT100406"/><ref name="Wilson"/>||align="center"| 0||align="center"| 0.54/gallon || <small> As of April 2008, Brazil does not import ethanol, the U.S. does</small>
|-
| colspan="4" align=left| <small>Notes: (1) Only contiguous U.S., excludes [[Alaska]]. (2) Assuming no land use change. <ref name= "Science07"/> (3) Excluding diesel-powered vehicles, ethanol consumption in the road sector is more than 40% <ref name="Wilson"/><ref name="Apollo"/> </small>
|}
==Environment==
=== Energy balance ===
<div style="float: right; margin-left: 10px">
{| class="wikitable"
|+ Energy balance <ref name=bourne>''Green Dreams'' J.K. Bourne JR, R. Clark [[National Geographic Magazine]] October 2007 p. 41 [http://magma.nationalgeographic.com/ngm/2007-10/biofuels/biofuels-interactive.html Article]</ref>
! style="background-color: #F3D161;" | Country
! style="background-color: #F3D161;" | Type
! style="background-color: #F3D161;" | Energy balance
|-----
| align="left" | {{USA}} || Corn ethanol || align="right" | 1.3
|-----
| align="left" | {{BRA}} || Sugarcane ethanol || align="right" | 8
|-----
| align="left" | {{GER}} || Biodiesel || align="right" | 2.5
|-----
| align="left" | {{USA}} || †Cellulosic ethanol || align="right" | ††2–36
|----
|}
† experimental, not in commercial production
†† depending on production method
</div>
{{main article|Ethanol fuel energy balance}}
All biomass goes through at least some of these steps: it needs to be grown, collected, dried, fermented, and burned. All of these steps require resources and an infrastructure. The total amount of energy input into the process compared to the energy released by burning the resulting ethanol fuel is known as the '''energy balance'''. Figures compiled in a 2007 by ''[[National Geographic Magazine]]''<ref name=bourne/> point to modest results for corn ethanol produced in the US: one unit of fossil-fuel energy is required to create 1.3 energy units from the resulting ethanol. The energy balance for sugarcane ethanol produced in Brazil is more favorable, 1:8. Energy balance estimates are not easily produced, thus numerous such reports have been generated that are contradictory. For instance, a separate survey reports that production of ethanol from sugarcane, which requires a tropical climate to grow productively, returns from 8 to 9 units of energy for each unit expended, as compared to corn which only returns about 1.34 units of fuel energy for each unit of energy expended.<ref name="BIOFUELS"> [http://www.iea.org/textbase/nppdf/free/2004/biofuels2004.pdf iea.org, biofuels2004.pdf]</ref>
[[Carbon dioxide]], a [[greenhouse gas]], is emitted during fermentation and combustion. However, this is canceled out by the greater uptake of carbon dioxide by the plants as they grow to produce the biomass.<ref>[http://www.oregon.gov/ENERGY/RENEW/Biomass/forum.shtml oregon.gov, biomass forum]</ref>
When compared to gasoline, depending on the production method, ethanol releases less [[greenhouse gas]]es.<ref>[http://www.transportation.anl.gov/pdfs/TA/58.pdf (pdf) (Wang ''et al.'' 1999)]</ref><ref>[http://www.transportation.anl.gov/pdfs/TA/271.pdf (pdf) (Wang 2002)]</ref>
===Air pollution===
Compared with conventional [[unleaded gasoline]], ethanol is a particulate-free burning fuel source that combusts with oxygen to form carbon dioxide, water and [[aldehydes]] (a contraction of alcohol [[dehydrogenated]]). Gasoline produces 2.44 [[CO2 equivalent]] kg/l and ethanol 1.94 (this is -21% CO2). The [[Clean Air Act]] requires the addition of [[oxygenate]]s to reduce carbon monoxide emissions in the United States. The additive [[MTBE]] is currently being phased out due to ground water contamination, hence ethanol becomes an attractive alternative additive. Current production methods include air pollution from the manufacturer of macronutrient [[fertilizer]]s such as ammonia.
A study by atmospheric scientists at Stanford University found that [[E85]] fuel would increase the risk of air pollution deaths relative to gasoline.<ref name="stanfordpollutionstudy">San Francisco Chronicle, April 18, 2007 [http://sfgate.com/cgi-bin/article.cgi?file=/c/a/2007/04/18/MNG7EPAN601.DTL Study warns of health risk from ethanol], accessed October 6, 2007.</ref> [[Ozone]] levels are significantly increased, thereby increasing photochemical smog and aggravating medical problems such as asthma.<ref>{{cite web
| url= http://pubs.acs.org/subscribe/journals/esthag-w/2007/apr/science/ee_ethanol.html
| title= "Clearing the air on ethanol"
|author= |last= |first= |authorlink= |coauthors=
| date= 2007-04-18 |work= | publisher= Environmental Science & Technology''
| accessdate= 2008-01-14 }} </ref><ref>{{cite web
| url= http://pubs.acs.org/cgi-bin/sample.cgi/esthag/asap/html/es062085v.html
| title= "Effects of Ethanol (E85) versus Gasoline Vehicles on Cancer and Mortality in the United States"
|author= Mark Z. Jacobson
|date= 2007-03-14 |publisher= ACS Publications
| accessdate= 2008-01-14 }} </ref>
===Manufacture===
In 2002, monitoring of [[ethanol plant]]s revealed that they released VOCs (volatile organic compounds) at a higher rate than had previously been disclosed.<ref> [http://www.cbsnews.com/stories/2002/05/03/tech/main508006.shtml CBS News]</ref> The [[United States Environmental Protection Agency|Environmental Protection Agency]] (EPA) subsequently reached settlement with [[Archer Daniels Midland]] and [[Cargill]], two of the largest producers of ethanol, to reduce emission of these VOCs. VOCs are produced when fermented corn mash is dried for sale as a supplement for livestock feed. Devices known as thermal oxidizers or catalytic oxidizers can be attached to the plants to burn off the hazardous gases.
===Carbon dioxide===
[[Image:BioEthanolFootprint.jpg|right|500px|thumb|Calculation of [[carbon intensity]] of corn bioethanol grown in the US and burnt in the UK, using UK government calculation <ref name="UKRTFO"/>]]
[[Image:BioethanolsCountryOfOrigin.jpg|right|500px|thumb|Graph of UK figures for the [[carbon intensity]] of bioethanol and [[fossil fuels]]. This graph assumes that all bioethanols are burnt in their country of origin and that prevously existing cropland is used to grow the feedstock.<ref name="UKRTFO"/>]]
The calculation of exactly how much carbon dioxide is produced in the manufacture of bioethanol is a complex and inexact process, and is highly dependent on the method by which the ethanol is produced and the assumptions made in the calculation. A calculation should include:
* The '''cost''' of growing the feedstock
* The '''cost''' of transporting the feedstock to the factory
* The '''cost''' of processing the feedstock into bioethanol
Such a calculation may or may not consider the following effects:
* The '''cost''' of the change in land use of the area where the fuel feedstock is grown.
* The '''cost''' of transportation of the bioethanol from the factory to its point of use
* The efficiency of the bioethanol compared with standard gasoline
* The amount of Carbon Dioxide produced at the tail pipe.
* The '''benefits''' due to the production of useful bi-products, such as [[cattle feed]] or electricity.
The graph on the right shows figures calculated by the UK government for the purposes of the [[Renewable transport fuel obligation]].<ref name=UKRTFO>[http://www.dft.gov.uk/pgr/roads/environment/rtfo/govrecrfa.pdf Carbon and Sustainability Reporting Within the Renewable Transport Fuel Obligation]</ref>
The January 2006 Science article from UC Berkeley's ERG, estimated reduction from corn ethanol in GHG to be 13% after reviewing a large number of studies. However, in a correction to that article released shortly after publication, they reduce the estimated value to 7.4%. A [[National Geographic Magazine]] overview article (2007)<ref name=bourne/> puts the figures at 22% less CO<sub>2</sub> emissions in production and use for corn ethanol compared to gasoline and a 56% reduction for cane ethanol. Carmaker Ford reports a 70% reduction in CO<sub>2</sub> emissions with bioethanol compared to petrol for one of their [[flexible-fuel vehicle]]s.<ref> [http://www.eubia.org/fileadmin/template/main/res/pics/projects/RESTMAC_-_Bioethanol_Production___Use.pdf Bioethanol Production and Use Creating Markets for Renewable Energy Technologies] EU, RES Technology Marketing Campaign, European Biomass Industry Association EUBIA 2007</ref>
An additional complication is that production requires tilling new soil<ref>New York Times, [http://www.nytimes.com/2008/02/08/science/earth/08wbiofuels.html?em&ex=1202792400&en=b90a6c6cca379cde&ei=5087%0A Biofuels Deemed a Greenhouse Threat Biofuels Deemed a Greenhouse Threat] by Rosenthal, Feb. 8, 2008.</ref> which produces a one-off release of GHG that it can take decades or centuries of production reductions in GHG emissions to equalize.<ref> Sciencexpress Report [http://www.sciencemag.org/cgi/content/abstract/1152747 Land Clearing and the Biofuel Carbon Debt] Fargione, Hill, [[G. David Tilman|Tilman]], Polasky, and Hawthorne. Feb. 7, 2008.</ref> As an example, converting grass lands to corn production for ethanol takes about a century of annual savings to make up for the GHG released from the initial tilling.<ref>New York Times, [http://www.nytimes.com/2008/02/08/science/earth/08wbiofuels.html?em&ex=1202792400&en=b90a6c6cca379cde&ei=5087%0A Biofuels Deemed a Greenhouse Threat Biofuels Deemed a Greenhouse Threat] by Rosenthal, Feb. 8, 2008.</ref>
===Change in land use===
Large-scale farming is necessary to produce agricultural alcohol and this requires substantial amounts of cultivated land. University of Minnesota researchers report that if all corn grown in the U.S. were used to make ethanol it would displace 12% of current U.S. gasoline consumption.<ref name="cornundrum"> {{cite web
| url= http://www1.umn.edu/umnnews/Feature_Stories/Ethanol_fuel_presents_a_cornundrum.html
| title= Ethanol fuel presents a corn-undrum
|author= Deane Morrison
|date= 2006-09-18 |publisher= [[University of Minnesota]]
| accessdate= 2008-01-14 }} </ref> There are claims that land for ethanol production is acquired through deforestation, while others have observed that areas currently supporting forests are usually not suitable for growing crops.<ref>{{cite web
| url= http://news.bbc.co.uk/2/hi/americas/6718155.stm
| title= "Lula calls for ethanol investment"
|author= |last= |first= |authorlink= |coauthors=
|date= 2007-06-04 |publisher= ''[[BBC]]''
|pages= |language= |doi= |archiveurl= |archivedate= |quote=
| accessdate= 2008-01-14 }} </ref><ref>{{cite web
| url= http://www.msnbc.msn.com/id/17500316/
| title= "Brazil's ethanol push could eat away at Amazon"
|date= 2007-03-07 |publisher= [[Associated Press]]
| accessdate= 2008-01-14 }} </ref> In any case, farming may involve a decline in soil fertility due to reduction of organic matter,<ref>Kononova, M. M. ''Soil Organic Matter, Its Nature, Its role in Soil Formation and in Soil Fertility'', 1961</ref> a decrease in water availability and quality, an increase in the use of pesticides and fertilizers, and potential dislocation of local communities.<ref>{{cite web
| url= http://actetsme.info/cms/index.php?option=com_content&task=view&id=178&Itemid=2
| title= Biofuels: An advisable strategy?
|author= Daniela Russi
|date= 2007-03-07 |work= |publisher=
|pages= |language= |doi= |archiveurl= |archivedate= |quote=
| accessdate= |accessmonthday= |accessdaymonth= |accessyear= }} </ref> However, new technology enables farmers and processors to increasingly produce the same output using less inputs.<ref name="cornundrum"/>
There is a concern that as demand for ethanol fuel increases, food crops are replaced by fuel crops, driving food supply down and food prices up. Growing demand for ethanol in the United States has been discussed as a factor in the increased corn prices in Mexico.<ref>Chomsky, Noam. “[http://www.commondreams.org/archive/2007/05/16/1238/ Starving The Poor].” ''The International News''. [[16 May]] [[2007]]. Retrieved 2007-05-17.</ref> Average barley prices in the United States rose 17% from January to June 2007 to the highest in 11 years. However, some commentators suggest that recent food price increases mainly reflect [[Oil price increases since 2003|high oil prices in recent years]], not specific pressures associated with ethanol production.<ref>[http://www.energybulletin.net/5045.html Why Our Food is So Dependent on Oil]</ref>
[[Cellulosic ethanol]] production is a new approach which may alleviate land use and related concerns. Cellulosic ethanol can be produced from any plant material, potentially doubling yields, in an effort to minimize conflict between food needs versus fuel needs. Instead of utilizing only the starch by-products from grinding wheat and other crops, cellulosic ethanol production maximizes the use of all plant materials, including gluten. This approach would have a smaller [[carbon footprint]] because the amount of energy-intensive fertilisers and fungicides remain the same for higher output of usable material. The technology for producing cellulosic ethanol is currently in the [[Cellulosic ethanol commercialization|commercialization stage]].<ref>International Energy Agency (2006). [http://www.worldenergyoutlook.org/summaries2006/English.pdf ''World Energy Outlook 2006''] p. 8.</ref><ref>Biotechnology Industry Organization (2007). [http://bio.org/ind/biofuel/CellulosicEthanolIssueBrief.pdf ''Industrial Biotechnology Is Revolutionizing the Production of Ethanol Transportation Fuel''] pp. 3-4.</ref>
Many analysts suggest that, whichever ethanol fuel production strategy is used, fuel conservation efforts are also needed to make a large impact on reducing petroleum fuel use.<ref>{{cite web
| url= http://grist.org/news/maindish/2006/12/04/montenegro/
| title= The Big Three
|author= Maywa Montenegro
|date= 2006-12-04 |work= |publisher= ''[[Grist (magazine)|]]''
| accessdate= 2008-01-14 }} </ref>
==Efficiency of common crops==
As ethanol yields improve or different feedstocks are introduced, ethanol production may become more economically feasible in the US. Currently, research on improving ethanol yields from each unit of corn is underway using biotechnology. Also, as long as oil prices remain high, the economical use of other feedstocks, such as [[cellulose]], become viable. By-products such as straw or wood chips can be converted to ethanol. Fast growing species like [[switchgrass]] can be grown on land not suitable for other cash crops and yield high levels of ethanol per unit area.<ref name=bourne>''Green Dreams'' J.K. Bourne JR, R. Clark [[National Geographic Magazine]] October 2007 p. 41 [http://magma.nationalgeographic.com/ngm/2007-10/biofuels/biofuels-interactive.html Article]</ref>
{| class="wikitable"
|-
! Crop
! Annual yield (Liters/hectare)
! Annual yield (US gal/acre)
! Greenhouse-gas savings (% vs. petrol)
! Comments
|-
| ''[[Miscanthus]]''
| 7300
| 780
| 37–73
| Low-input perennial grass. Ethanol production depends on development of cellulosic technology.
|-
| [[Switchgrass]]
| 3100–7600
| 330–810
| 37–73
| Low-input perennial grass. Ethanol production depends on development of cellulosic technology. Breeding efforts underway to increase yields. Higher biomass production possible with mixed species of perennial grasses.
|-
| [[Poplar]]
| 3700–6000
| 400–640
| 51–100
| Fast-growing tree. Ethanol production depends on development of cellulosic technology. Completion of genomic sequencing project will aid breeding efforts to increase yields.
|-
| [[Sugar cane]]
| 5300–6500
| 570–700
| 87–96
| Long-season annual grass. Used as feedstock for most bioethanol produced in Brazil. Newer processing plants burn residues not used for ethanol to generate electricity. Only grows in tropical and subtropical climates.
|-
| [[Sweet sorghum]]
| 2500–7000
| 270–750
| No data
| Low-input annual grass. Ethanol production possible using existing technology. Grows in tropical and temperate climates, but highest ethanol yield estimates assume multiple crops per year (only possible in tropical climates). Does not store well.<ref>{{cite web
| url= http://www.iwmi.cgiar.org/EWMA/files/papers/Paper%20for%20Bioenergy%20and%20water-BelumReddy.pdf
| title= "Sweet sorghum: A Water Saving BioEnergy Crop"
|author= Belum V S Reddy |coauthors= A Ashok Kumar and S Ramesh
|date= |year= |month= |format= |work=
|publisher= International Crops Research Institute for the SemiArid Tropics
| accessdate= 2008-01-14 }} </ref><ref>{{cite web
| url= http://www.bic.searca.org/news/2006/oct/phi/25.html
| title= RP INVESTOR TO PUT UP PIONEERING SWEET SORGHUM ETHANOL PLANT
|author= |last= |first= |authorlink= |coauthors=
|date= 25-October-2006 |publisher= Manila Bulletin
| accessdate= 2008-01-14 }} </ref><ref>{{cite web
| url= http://www.hort.purdue.edu/newcrop/proceedings1993/v2-394.html
| title= Sweet Sorghum for a Piedmont Ethanol Industry
|author= Glen C. Rains |coauthors= John S. Cundiff, and Gregory E. Welbaum
|date= 1997-09-12|work= |publisher=
| accessdate= 2008-01-14 }} </ref><ref>{{cite web
| url= http://www.icrisat.org/Media/2004/media13.htm
| title= ICRISAT develops sweet sorghum for ethanol production
|author= |last= |first= |authorlink= |coauthors=
|date= 2004-08-12 |work= |publisher=
| accessdate= 2008-01-14 }} </ref>
|-
| [[Maize|Corn]]
| 3100–3900
| 330–420
| 10–20
| High-input annual grass. Used as feedstock for most bioethanol produced in USA. Only kernels can be processed using available technology; development of commercial cellulosic technology would allow stover to be used and increase ethanol yield by 1,100 - 2,000 litres/ha.
|-
|colspan=5|<small>Source (except sorghum): ''Nature'' 444 ([[December 7]], [[2006]]): 673-676.</small>
|-
|}
==Reduced petroleum imports and costs==
One rationale given for extensive ethanol production in the U.S. is its benefit to [[energy security]], by shifting the need for some foreign-produced oil to domestically-produced energy sources.<ref> http://ethanol.org [http://ethanol.org/pdf/contentmgmt/Energy_Security_Issue_Brief.pdf Energy Security]</ref> <ref name="Turon1998">{{Citation | last = Turon, Martin | title = [http://www.turon.com/papers/ethanol.htm Ethanol as Fuel: An Evironmental and Economic Analysis] | date = 1998-11-25| publisher = U.C. Berkeley, Chemical Engineering }}</ref>Production of ethanol requires significant energy, but current U.S. production derives most of that energy from coal, natural gas and other sources, rather than oil.<ref> http://www.ethanol.org [http://www.ethanol.org/pdf/contentmgmt/Science_Journal_January_2006.pdf Ethanol Can Contribute to Energy and Environmental Goals]</ref> Because 66% of oil consumed in the U.S. is imported, compared to a net surplus of coal and just 16% of natural gas (2006 figures),<ref> http://www.eia.doe.gov [http://www.eia.doe.gov/neic/brochure/infocard01.htm Energy INFOcard]</ref> the displacement of oil-based fuels to ethanol produces a net shift from foreign to domestic U.S. energy sources.
According to a 2008 analysis by Iowa State University, the growth in US ethanol production has caused retail gasoline prices to be US $0.29 to US $0.40 per gallon lower than would otherwise have been the case.<ref>[http://www.renewableenergyworld.com/rea/news/infocus/story?id=52564 Ethanol Lowers Gas Prices 29-40 Cents Per Gallon]</ref>
==Recent patents==
In 2006-2-23, Veridium Corporation announced the technology to convert exhaust carbon dioxide from the fermentation stage of ethanol production facilities back into new ethanol and biodiesel. The bioreactor process is based on a new strain of iron-loving blue-green algae discovered thriving in a hot stream at [[Yellowstone National Park]].<ref>[http://www.treehugger.com/files/2006/03/veridian_corp_e.php Veridium Patents Yellowstone Algae-Fed Bioreactor to Capture Ethanol Plant CO2 Emissions]</ref>
In 2006-11-14, US Patent Office approved Patent 7135308, a process for the production of ethanol by harvesting starch-accumulating filament-forming or colony-forming algae to form a biomass, initiating cellular decay of the biomass in a dark and anaerobic environment, fermenting the biomass in the presence of a yeast, and the isolating the ethanol produced.<ref> [http://patft.uspto.gov/netacgi/nph-Parser?Sect1=PTO2&Sect2=HITOFF&p=1&u=%2Fnetahtml%2FPTO%2Fsearch-bool.html&r=1&f=G&l=50&co1=AND&d=PTXT&s1=7135308&OS=7135308&RS=7135308 US patent 7135308]</ref>
==Criticism and controversy==
{{main|Food vs fuel}}
According to an April 2008 [[World Bank]] report, biofuels have caused world food prices to increase by 75-percent.<ref>{{cite web |url=http://news.yahoo.com/s/afp/20080704/ts_afp/climateenvironmentbiofuelsworldbankusbritain;_ylt=At_X.9OZ0U8sMmq0i5jdpI2GOrgF |title=Biofuels behind food price hikes: leaked World Bank report}}</ref> In 2007, biofuels consumed one third of America's corn (maize) harvest. Filling up one large vehicle fuel tank one time with 100% ethanol uses enough corn to feed one person for a year. Thirty million tons of U.S. corn going to ethanol in 2007 greatly reduces the world's overall supply of grain.<ref>{{cite web |url= http://www.economist.com/research/articlesBySubject/displaystory.cfm?subjectid=7216688&story_id=10252015 | title= The Economist – The End Of Cheap Food}}</ref> However, 31% of the corn put into the process comes out as distiller's grain, or DDGS, which is very high in protein, and is used to feed livestock.<ref>{{cite web |url=http://www.ers.usda.gov/AmberWaves/April06/Features/Ethanol.htm | title= Amber Waves - Ethanol Reshapes the Corn Market}}</ref>
[[Jean Ziegler]], the [[United Nations Special Rapporteur]] on the Right to Food, called for a five-year moratorium on biofuel production to halt the increasing catastrophe for the poor. He proclaimed that the rising practice of converting food crops into biofuel is "A Crime Against Humanity," saying it is creating food shortages and price jumps that cause millions of poor people to go hungry.<ref>{{cite web
| url= http://www.livescience.com/environment/071027-ap-biofuel-crime.html
| title= Crime Against Humanity}}</ref>
The European Organisation for Economic Co-operation and Development warns that “the current push to expand the use of biofuels is creating unsustainable tensions that will disrupt markets without generating significant environmental benefits.”<ref>{{cite web
| url= http://www.ft.com/cms/s/0/e780d216-5fd5-11dc-b0fe-0000779fd2ac.html?nclick_check=1
| title= Financial Times: OECD Warns Against Biofuels Subsidies}}</ref>
When all 200 American ethanol subsidies are considered, they cost about $7 billion USD per year (equal to roughly $1.90 USD total for each a gallon of ethanol).<ref>{{cite web
| url= http://www.economist.com/displaystory.cfm?story_id=10250420
| title= The Economist - Food Prices: Cheap No More}}</ref> When the price of one agricultural commodity increases, farmers are motivated to quickly shift finite land and water resources to it, away from traditional food crops.<ref>{{cite web
| url= http://www.economist.com/displaystory.cfm?story_id=10250420
| title= The Economist - Food Prices: Cheap No More}}</ref>
The 2007-12-19 U.S. [[Energy Independence and Security Act of 2007]] requires American “fuel producers to use at least 36 billion gallons of biofuel in 2022. This is nearly a fivefold increase over current levels.”<ref>{{cite web
| url= http://www.whitehouse.gov/news/releases/2007/12/20071219-6.html
| title= Bush Signs Energy Independence and Security Act of 2007}}</ref>
When cellulosic ethanol is produced from feedstock like switchgrass and sawgrass, the nutrients required to grow the cellulose are removed and cannot decay and replenish the soil. The soil is of poorer quality, and unsustainable soil erosion occurs.
Ethanol production consumes large quantities of unsustainable petroleum and natural gas. Even with the most-optimistic energy [[return on investment]] claims, in order to use 100% [[solar energy]] to grow corn and produce ethanol (fueling farm-and-transportation machinery with ethanol, distilling with heat from burning crop residues, using no fossil fuels), the consumption of ethanol to replace current U.S. petroleum use alone would require about 75% of all cultivated land on the face of the Earth, with no ethanol for other countries, or sufficient food for humans and animals.<ref>{{cite web
| url= http://www.oecd.org/dataoecd/52/25/36760950.pdf
| title= Global Science Forum Conference on Scientific Challenges for Energy Research: Energy At The Crossroads}}</ref>
===Fuel system problems===
Several of the outstanding ethanol fuel issues are linked specifically to fuel systems. Fuels with more than 10% ethanol are not compatible with non E85-ready fuel system components and may cause [[corrosion]] of [[Iron|ferrous]] components.<ref name=FCAI>''[http://www.fcai.com.au/ethanol.php/2006/12/00000005.html Capability of vehicles to satisfactorily operate on Ethanol Blend petrol]'' 8 August 2006. Federal Chamber of Automotive Industries. Retrieved on [[2007]]-[[04-09]].</ref><ref name=2000HOURS>Orbital Fuel Company. ''[http://www.environment.gov.au/atmosphere/fuelquality/publications/2000hours-vehicle-fleet/pubs/2000-hours-vehicles.pdf Market Barriers to the Uptake of Biofuels Study]'' May 2003. Environment Australia. Retrieved on [[2007]]-[[04-29]]</ref> Ethanol fuel can negatively affect electric fuel pumps by increasing internal wear,<ref name=2000HOURS /> cause undesirable spark generation,<ref>{{cite web
| url= http://www.oilgae.com/energy/sou/ae/re/be/alc/eth/eth.html
| title= Ethanol Production Plant, Fuel Stock e85, Cellulosic Corn Ethanol, Prices
|author= |last= |first= |authorlink= |coauthors=
|date= |year= |month= |format= |work= |publisher=
|pages= |language= |doi= |archiveurl= |archivedate= |quote=
| accessdate= 2008-01-14 }} </ref> and is not compatible with [[capacitance]] fuel level gauging indicators and may cause erroneous fuel quantity indications in vehicles that employ that system.<ref> ''[http://commerce.wi.gov/ER/pdf/bst/ProgramLetters_PL/ER-BST-PL-EthanolMotorFuelStorageOverview.pdf Ethanol Motor Fuel Storage Overview]'' September 2005. Wisconsin Department of Commerce. Retrieved on [[2007]]-[[04-29]]</ref> It is also not always compatible with marine craft, especially those that use fiberglass fuel tanks.<ref>{{cite web
| url= http://the.honoluluadvertiser.com/article/2007/Apr/11/ln/FP704110403.html
| title= "Ethanol fuel gunking up Island boats"
|author= Dan Nakaso |date= 2007-04-11 |publisher= ''[[Honolulu Advertiser]]''
| accessdate= 2008-01-14}} </ref><ref>{{cite web
| url= http://www.hawaii.gov/dbedt/ert/new-fuel/files/boat-CTarticle.pdf
| title= New Fuels: Gasoline and Diesel
|author= Philip Gaudreau
|date= |year= |month= |format= [[PDF]] |work= |publisher=
| accessdate= 2008-01-14 }} </ref>
Using 100% ethanol fuel decreases fuel-economy by 15-30% over using 100% gasoline; this can be avoided using certain modifications that would, however, render the engine inoperable on regular petrol without the addition of an adjustable [[Engine control unit|ECU]].<ref>{{cite web
| url= http://www.ethanolrfa.org/resource/facts/engine/
| title= Ethanol Facts: Engine Performance
|author= |last= |first= |authorlink= |coauthors=
|date= |year= |month= |format= |work= |publisher=
| accessdate= 2008-01-14 }} </ref><!--
404 Not Found
<ref>{{cite web
| url= http://www.eere.energy.gov/afdc/afv/eth_vehicles.html
| title=
|author= |last= |first= |authorlink= |coauthors=
|date= |year= |month= |format= |work= |publisher=
|pages= |language= |doi= |archiveurl= |archivedate= |quote=
| accessdate= |accessmonthday= |accessdaymonth= |accessyear= }} </ref>
-->
Tough materials are needed to accommodate a higher compression ratio to make an ethanol engine as efficient as it would be on petrol; these would be similar to those used in diesel engines which typically run at a CR of 20:1,<ref name=FUELECON>{{cite web
| url= http://www.denburydiesels.co.uk/diesel-performance.asp
| title= Performance Tuning for Diesel Cars & Vans
|author= |last= |first= |authorlink= |coauthors=
|date= |year= 2008 |month= |format= |work= |publisher= Denbury Diesels
|pages= |language= |doi= |archiveurl= |archivedate= |quote=
| accessdate= 2008-01-14 }} </ref> versus about 8-12:1 for petrol engines.<ref> {{cite web
| url= http://www.firstscience.com/home/blog/107.html
| title= The Science And Costs of Diesel Cars
|author= Marc West |date= 2007-03-01 |work= |publisher=
| accessdate= 2008-01-14 }} </ref>
In April 2008 the German environmental minister cancelled a proposed 10% ethanol fuel scheme citing technical problems: too many older cars in [[Germany]] are unequipped to handle this fuel. Ethanol levels in fuel will remain at 5%.<ref>[Gabriel stoppt die Biosprit-Verordnung http://www.welt.de/wirtschaft/article1869275/Gabriel_stoppt_die_Biosprit-Verordnung.html] [[Die Welt]] 4 April 2008</ref>
== Bibliography ==
* {{Citation
| last = Goettemoeller, Jeffrey; Adrian Goettemoeller
| title = Sustainable Ethanol: Biofuels, Biorefineries, Cellulosic Biomass, Flex-Fuel Vehicles, and Sustainable Farming for Energy Independence
| year = 2007
| publisher = Praire Oak Publishing, Maryville, Missouri
| id = ISBN 978-0-9786293-0-4 . ''Brief and comprehensive account of the history, evolution and future of ethanol.''
}}
* {{Citation
| last = The Worldwatch Institute
| title = Biofuels for Transport: Global Potential and Implications for Energy and Agriculture
| year = 2007
| publisher = Earthscan Publications Ltd., London, U.K.
| id = ISBN 978-1-84407-422-8 . ''Global view, includes country study cases of Brazil, China, India and Tanzania''.
}}
==References==
<!-- See http://en.wikipedia.org/wiki/Wikipedia:Footnotes for an explanation of how to generate footnotes using the <ref(erences/)> tags -->
{{reflist|2}}
==See also==
{{Portal|Ecology}}
{{portal|energy}}
{{Portalpar|Sustainable development|Sustainable development.svg}}
{|
|- valign=top
| width=250 align=left |
*[[Alcohol fuel]]
*[[Aventine Renewable Energy]]
*[[Biobutanol]], a [[gasoline]] replacement.
*[[Bioconversion of biomass to mixed alcohol fuels]]
*[[Biodiesel]]
*[[Biofuel]]
*[[Biomass]]
*[[Cellulosic ethanol]]
*[[Corn Ethanol]]
*[[Comparison of automobile fuel technologies]]
*[[2,5-Dimethylfuran|DMF]] (potential ethanol competitor biofuel)
| width=250 align=left |
*[[Energy crop]]
*[[Energy development]]
*[[Ethanol fuel in Australia]]
*[[Ethanol fuel in Brazil]]
*[[Ethanol fuel in Sweden]]
*[[Ethanol fuel in the Philippines]]
*[[Ethanol fuel in the United States]]
*[[Flex Fuel]]
*[[Food vs fuel]]
*[[Hydrogen fuel]]
*[[Jatropha]]
*[[Leavening]]
*[[Liquid fuels]]
*[[List of energy topics]]
| width=250 align=left |
*[[MTBE]] (now banned).
*[[Oil crisis]]
*[[P-series fuels]]
*[[Sugarcane]]
*[[Timeline of alcohol fuel]]
*[[Vegetable oil economy]]
|}
==External links==
* {{HSW|make-your-own-ethanol|Can I make my own ethanol?}}
* [http://econ.worldbank.org/WBSITE/EXTERNAL/EXTDEC/EXTRESEARCH/EXTWDRS/EXTWDR2008/0,,contentMDK:21501336~pagePK:64167689~piPK:64167673~theSitePK:2795143,00.html World Bank, Biofuels: The Promise and the Risks. World Development Report 2008: Agriculture for Development]
* {{dmoz|Science/Technology/Energy/Renewable/Biomass_and_Biofuels/Ethanol/|Biofuels: Ethanol}}
* [http://www.gea-wiegand.com/geawiegand/cmsresources.nsf/filenames/Bioethanol_Technolgoy_GEA_Wiegand_en.pdf/$file/Bioethanol_Technolgoy_GEA_Wiegand_en.pdf Bio Ethanol Brochure]
{{Bioenergy}}
{{environmental technology}}
[[Category:Alternative propulsion]]
[[Category:Biofuels]]
[[Category:Biotechnology products]]
[[Category:Ethanol fuel]]
[[Category:Liquid fuels]]
[[ar:الإثانول الحيوي]]
[[bg:Биоетанол]]
[[cs:Bioethanol]]
[[da:Bioætanol]]
[[de:Bioethanol]]
[[et:Bioetanool]]
[[es:Etanol (combustible)]]
[[eo:Bioetanolo]]
[[fr:Bioéthanol]]
[[id:Bahan bakar etanol]]
[[it:Bioetanolo]]
[[kk:Биоэтанол]]
[[hu:Bioetanol]]
[[ja:バイオマスエタノール]]
[[no:Bioetanol]]
[[pt:Álcool combustível]]
[[ru:Биоэтанол]]
[[sk:Bioetanol]]
[[sl:Etanol kot gorivo]]
[[fi:Bioetanoli]]
[[tr:Etanol yakıtı]]
[[uk:Газоголь]]