E85

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Logo used in the United States for E85 fuel
Logo used in the United States for E85 fuel

E85 is an alcohol fuel mixture that typically contains a mixture of up to 85% denatured fuel ethanol and gasoline or other hydrocarbon by volume. On an undenatured basis, the ethanol component ranges from 70% to 83%. E85 as a fuel is widely used in Sweden and is becoming increasingly common in the United States, mainly in the Midwest where corn is a major crop and is the primary source material for ethanol fuel production.

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[edit] Use in flexible-fuel engines

E-85 ethanol is used in engines modified to accept higher concentrations of ethanol. Such flexible-fuel engines are designed to run on any mixture of gasoline or ethanol with up to 85% ethanol by volume. The primary differences from non-FFVs is the elimination of bare magnesium, aluminum, and rubber parts in the fuel system, the use of fuel pumps capable of operating with electrically conductive (ethanol) instead of non-conducting dielectric (gasoline) fuel, specially-coated wear-resistant engine parts, fuel injection control systems having a wider range of pulse widths (for injecting approximately 60% more fuel), the selection of stainless steel fuel lines (sometimes lined with plastic), the selection of stainless steel fuel tanks in place of terne fuel tanks, and, in some cases, the use of acid-neutralizing motor oil. For vehicles with fuel-tank mounted fuel pumps, additional differences to prevent arcing, as well as flame arrestors positioned in the tank's fill pipe, are also sometimes used.[citations needed]

Historically, the first widely-sold flexible-fuel vehicle in the United States was a variant of Henry Ford's Model T intended for use by self-reliant farmers who could make their own ethanol. Surprisingly, it is capable even to this day of running on E85, or gasoline, as it was designed to operate on either ethanol or gasoline, at the user's choice. Henry Ford's subsequent 1927 Model A likewise was an early flex fuel vehicle. It, however, eased the driver's method of accommodating various blends of ethanol and gasoline through a driver's control on the dash with a knob that was turned to control air fuel mixture and pulled to choke the single-barrel Zenith carburetor. This dash-mounted control provided easy control of all the major adjustments required for easily burning ethanol and gasoline in varying proportions, including enough range for burning today's E85 blend of ethanol and gasoline.[citations needed]

Modern flexible-fuel vehicles have come a long way since the Model T and Model A, and now automatically adapt themselves to burning changing percentages of ethanol and gasoline without any user intervention required. So far, most flexible-fuel vehicles that have been built in the United States have been sport-utility vehicles and other members of the "light truck" vehicle class, with smaller numbers of sedans, station wagons, and the like. The United States government corporate average fuel economy (CAFE) regulations are relaxed for FFV. For example, an FFV GMC Yukon is rated 33 mpg for CAFE purposes, when its EPA ratings are 15 mpg city, 20 mpg highway.[citations needed]General Motors has been a modern leader in flexible fuel engines, as their Swedish subsidiary Saab has developed a turbocharged flexible-fuel engine called the BioPower which takes special advantage of the high-octane fuel. This engine allows the vehicle to accelerate faster and attain higher speeds when running on E85 than when running on straight gasoline. Tests done using older Saabs fitted with the APC system shows that they can run fine on up to 50% E85 mixed with ordinary petrol. However it may have long term effects as ethanol is more aggressive on tubes and the petrol also acts as a lubricant.[citations needed]

Their Brazilian subsidiary adopted GM's Family II and Family 1 straight-4 engines with FlexPower technology that enables the use of ethanol, gasoline, or their mixture. The vehicles with FlexPower include the Chevrolet Corsa and the Chevrolet Astra.[citations needed]

E85 has an octane rating of 105, which is higher than typical commercial gasoline mixtures (octane ratings of 85 to 98); however, it does not burn as efficiently in traditionally-manufactured internal-combustion engines. Additionally, E85 contains less energy per volume as compared to gasoline. Although E85 contains only 72% of the energy on a gallon-for-gallon basis compared to gasoline, experimenters have seen slightly better fuel mileage than the 28% this difference in energy content implies. For example, recent tests by the National Renewable Energy Lab on fleet vehicles owned by the state of Ohio showed about a 25% reduction in mpg [1] (see table on pg 5) comparing E85 operation to reformulated gasoline in the same flexible fuel vehicle. Results compared against a gasoline-only vehicle were essentially the same, about a 25% reduction in volumetric fuel economy with E85.]]

[edit] Estimating fuel injector, carburetor and fuel pump requirements

Fuel injector, carburetor jet sizing, and fuel pump requirements can be estimated by using the following rules of thumb as a starting point. For a naturally aspirated (NA) engine (carbureted) on gasoline most need a brake specific fuel consumption (BSFC) for gasoline of 0.50 lb/(hp·h). On E85 the same NA engine would need a BSFC of about 0.65 lb/(hp·h).

Turbocharged engines typically need BSFC fueling of about 0.60 lb/(hp·h), a reasonable first guess for fueling required on E85 would be 0.77 lb/(hp·h).

For a simple conversion to replace gasoline with E85 take the current "flywheel horsepower" as a reference point. With E85, power should increase by about 5%, so the estimated E85 fueling would be:

(BHPgasoline x 1.05) x BSFCe85 = Estimated E85 fuel requirements.

[edit] Life cycle impact of E85 on greenhouse gas emissions

Use of E85 results in reductions of greenhouse gas emissions and energy use for each gallon burned, compared to the emissions and energy use for the gasoline it replaces.[1][2]

Using corn based fuel ethanol production, E85 has a significant effect on total fossil fuel / energy usage and greenhouse gas (GHG) emissions. As process efficiency increases over the coming years, these benefits are expected to continue to improve. A recent study by University of California at Berkeley estimates it cuts greenhouse-gas emissions by 13% over gasoline.[citation needed]

E85 produces less energy per gallon than gasoline, translating in fewer miles per gallon. Until the price of E85 drops to 72% the price of gasoline, consumers won't see any savings in fuel costs per mile. (It would cost $2,781 to drive a Chevy Tahoe FFV 15,000 miles on E85, over $300 more than gasoline).

Using dry milling process technology (circa 1999) each gallon of E85 burned reduced petroleum usage by an estimated 0.949 gallon (0.949 L/L). Reduced GHG emissions by 23.8%, compared to burning a gallon of gasoline, and reduced life cycle fossil energy consumption by 44.4% compared to gasoline.

On a per-mile-driven basis, using 1999 technology, dry milling process derived E85, reduced petroleum usage by 74.9%, GHG emissions by 18.8%, and total fossil energy consumed by 35%. Wet milling derived E85 with 1999 technology would net reductions of 72.5% in petroleum usage, 13.7% in GHG emissions, and 34.4% in fossil energy used.

Using more recent state of the art (circa 2005) the energy usage figures improve slightly, with an appreciable decrease in GHG emissions. Dry mill current technology reduces petroleum usage by 75.6%, GHG emissions by 25.5% and fossil energy use by 40.7%. Wet mill current technology reduces petroleum usage by 73.7%, GHG by 23.8% and fossil energy by 42.5%.

Using cellulose based processes, the reductions in petroleum, GHG, and fossil energy are expected to reach the following levels in a mature production environment. Cellulose based ethanol production is nearing commercial viability at this time (2006). Woody biomass process (near future technology) petroleum reduction 69.9%, GHG emissions 102.2% (taking GHGs out of the atmosphere) and fossil energy usage 79%. Herbaceous biomass process (near future technology) petroleum usage reduction of 71.4%, GHG emissions 67.6% and fossil energy 70.4%.

Skeptics caution, however, that these potential benefits are balanced, and possibly offset, by a significant cost in the form of farmland. It has been estimated that the land area required to operate a motor vehicle for one year on pure ethanol, 11 acres, could feed 7 people over the same timeframe.[2] The logical consequences of these competing land uses are that widespread use of ethanol would lower food production from existing agricultural land, potentially inflating food prices due to less supply. Alternatively, the agricultural industry could maintain existing levels of food production and create more farmland — through deforestation — upon which to grow crops for energy production. Ironically, this could lead to the acceleration of the greenhouse effect as well as the loss of biodiversity.

It should be pointed out though, that many of these concerns are derived from studies by a single author (Pimental) which have been rebutted by several reports.[3][4]

Their conclusion is these series of assumptions may not be entirely appropriate. For example, if the use of ethanol is extended to 100% usage to cover today's fuel energy needs, using exclusively corn derived ethanol, the obvious conclusion is that too much farm land will be required for this usage. This is not likely given current events. Likewise corn used in ethanol production does not remove human food crops from the food chain, as the nutrients are retained and reintroduced to the human food chain through high quality livestock feed. [5]

Ethanol can be brewed from any organic source that contains sugar or starch using current technology. This includes other crops besides corn, such as rice, wheat, barley, potatoes, sugar beets, and sugar cane. At the moment the most cost effective crop in the USA is corn. There is however no reason to assume that will continue into the future. Alternate feed stock streams are already coming on line as producers and manufactures realize that their waste can be converted to a product with market value. For example, Coors Brewing Company is producing 1.5 million gallons per year of fuel ethanol from waste beer and is expanding that output an additional 1.5 million gallons per year in the near future.[6] Others have discussed using otherwise waste crops like freeze damaged fruit, over ripe produce like apples and even out of date bakery goods like stale bread and cakes as possible feed stock streams for ethanol plants.

If cellulose becomes a cost effective feed stock for ethanol, it will become economic to use waste products from other processes or discards, such as waste paper from trash, or stalks and stemmage from crops. Certain high-yield plants grown expressly as a source of cellulose may thrive in climates where food and timber crops do not.

[edit] Ethanol Producers

World's largest ethanol producer

Brazil is currently the world's leader in ethanol production. Because of government subsidies, large sugarcane crops, and high sales taxes on gasoline, Brazil has built a profitable national ethanol industry. Sugarcane is grown in the country as the climate presents perfect conditions for its cultivation and production. It converts very easily to ethanol, and provides Brazil with huge supplies of ethanol. Coimex Trading, a subsidiary of Brazilian conglomerate Grupo Coimex, is the largest producer of ethanol in Brazil.

Largest producer of ethanol in the U.S.

The largest producer of ethanol in the U.S. is Archer Daniels Midland Corporation. ADM is a company that is an agricultural giant in the United States, and has decades of experience. They have a vast network of railcars, trucks, storage facilities, and barges that are capable of delivering high-grade ethanol. They are also working on new ways to produce ethanol that draw on agricultural waste products like cellulose. ADM has made profits of $10.98 billion in 2006, and operates in North America, South America, Europe, Middle East, Africa, Asia and Pacific Rim.

[edit] Power output and usage in racing

E85 has been repeatedly shown to produce more power than a comparable gasoline fuel, especially in engines that need high octane fuels to avoid early detonation.[3] Ford Motor Company found that power typically increased approximately 5% with the switch to E85 [4]. Researchers working on the equivalent of E85 fuel for general aviation aircraft AGE-85 have seen the same results with an aircraft engine jumping from 600 hp on conventional 100LL AV gas to 650 hp on the AGE-85. Recorded power increases range from 5% to 9% depending on the engine. [5][6]

Due to pressure to remove leaded fuel even from racing environments, several racing organizations are looking at ethanol or E85 fuels as suitable alternative fuels for high performance race engines.

In 2007, the Swedish Touring Car Championship, STCC, will have cars running on E85.

In Swedish rallying, as of 2006, approx. 30% of competitors were running their rally cars on E85. There is also a rally cup (Ford Flexifuel Cup) using Ford Fiestas in Gr. N, which started in 2006.

In 2006, the National Street Car Association is adopting E85 as an approved fuel for both their American Muscle Car and Street Machine (racing class) eliminator racing classes.

The National Hot Rod Association (NHRA) currently allows ethanol as an approved fuel in several of its racing classes. NHRA approved ethanol is allowed in their bracket classes, Hotrod, Modified, ProFWD, and ProRWD classes to name some of the more popular. At this time NHRA has not announced any plans to include E85 as an approved fuel in the classes that are currently limited to "pump fuels".

The Indy Racing League is likewise moving to ethanol based fuels in 2006, with 10% ethanol 90% methanol fuel blend, and switching to a 100% ethanol fuel in the 2007 racing season.

General Motors Performance Division's GM Student Cobalt driven by Mark Dickens went 172.680 mph at Bonneville Speed Weeks August 2006, setting a new record for G/FCC class on E85 fuel. This run broke a 19-year-old record of 152.626 mph set by Doc Jeffries in 1987. [7]

There is much discussion of NASCAR also making the switch to an ethanol based fuel in the future. During selected 2006 Craftsman Truck Series races, the Chevrolet Silverado pace truck, such as the one in the GM Flex-Fuel 250, will be fueled by E85, and a marketing campaign with Morgan-Dollar Motorsports resulted in one of their trucks' numbers changed to #85 to promote E85 fuel such as the one used in the pace truck.

In 2006, Shell announced V8 Supercar will use Shell Optimax Extreme, a premium unleaded fuel blended with five percent ethanol.

Interest in E85 is high enough that there are now competitions for engine builders to develop winning combinations for both power and fuel economy on this fuel. One such competition is sponsored by the AERA Engine Builders Association. [8].

[edit] Current E85 flexible-fuel cars

Please see Flexible-fuel vehicle.

[edit] See also

Portal:energy
 energy Portal

[edit] Notes

  1. ^ http://www.transportation.anl.gov/pdfs/TA/58.pdf
  2. ^ http://www.transportation.anl.gov/pdfs/TA/349.pdf
  3. ^ http://www.ncga.com/public_policy/PDF/03_28_05ArgonneNatlLabEthanolStudy.pdf
  4. ^ http://www.ncga.com/ethanol/pdfs/EthanolfFuelsRebuttal.pdf
  5. ^ A review of various studies of the energy return on investment for corn ethanol is available here: http://www.nrdc.org/air/transportation/ethanol/ethanol.pdf
  6. ^ http://www.greencarcongress.com/2005/10/coors_doubling_.html

[edit] References

  • US Department of Energy

Handbook for Handling Storing and Dispensing E85 National Rewnewable Energy Laboratory, April 2006

[edit] External links

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