Jump to content

E85

From Wikipedia, the free encyclopedia

This is an old revision of this page, as edited by Karldw (talk | contribs) at 16:52, 8 December 2010 (→‎Comparisons to regular gasoline: Fixed dead link). The present address (URL) is a permanent link to this revision, which may differ significantly from the current revision.

This article is about alcohol fuel. For a motorway in Europe, see European route E85. For BMW's platform designation, see BMW Z4.
Logo used in the United States for E85 fuel

E85 is an abbreviation for flex fuel meaning a mixture of up to 85% denatured fuel ethanol and gasoline or other hydrocarbon (HC) by volume. Some vehicles such as the Ford Model T can operate on 100 percent pure alcohol fuel, however it is more common to combine gasoline and ethanol to receive some benefits from both fuel types.[1]

Some of the benefits of E85 over conventional gasoline powered vehicles include the potential for localized production of fuel in agricultural areas. Another benefit is potentially reduced pollution emissions especially Carbon dioxide in Earth's atmosphere which is an important element for adaptation to global warming.

Potential benefits of E85 are contested by some experts who point out that deriving gasoline from petroleum is a relatively inexpensive (i.e. more efficient) process even including the transportation of oil and gasoline long distances. Large-scale production of ethanol may be cost prohibitive; and may result in a net energy loss when taking into account all the energy required to make alcohol from starchy plants. Another drawback for E85 is that, in a liter-to-liter comparison, E85 has less power potential than conventional gasoline; about 12-25 percent less energy for transportation by volume. Other experts believe that, if the world was to mix as much alcohol into our automobiles as we do into our brains we might make progress on the global warming issue. [citation needed]

Availability

North America

E85 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; however as yet, there are about 2335 filling stations selling E85 to the public in the US,[2] and, until recently, only three in Canada.[3][4]

Europe

E85 as a fuel is widely used in Sweden however most of it is imported from Italy and Brazil

It is also available across most of the Maxol chain in Ireland where it is made from whey, a byproduct of cheese manufacturing.[5]

In Finland E85 is available from seven St1 chain locations in Helsinki. The Finnish E85 is manufactured from bio waste.

Fuel economy

Because ethanol contains less energy than gasoline, fuel economy is reduced for most 2002 and earlier American FFVs (flexible-fuel vehicles) that are currently on the road by about 30% (most after 2003 lose only 15-17%, or less) when operated on pure E85 (summer blend). Some of the newest American vehicles can lessen this reduction to only 5-15%, but as recently as 2007 the Environmental Protection Agency stated on its website that several of the most current American FFVs were still losing 25-30% fuel efficiency when running on E85. Some Swedish engineered cars with engine management systems provide much better fuel economy on E85 than on gasoline; for example, the Saab Aero-X turbocharged concept car produces higher fuel economy and higher power on 100% ethanol (E100) than gasoline through using a higher compression ratio engine with advanced SAAB engine control computers. Another car that has higher power on ethanol is the Koenigsegg CCXR, which on ethanol is the third most powerful production car with 1020 hp. This according to the manufacturer is due to the cooling properties of ethanol. Still, for almost all American-made FFVs, more E85 is typically needed to do the same work as can be achieved with a lesser volume of gasoline. This difference is sometimes offset by the lower cost of the E85 fuel, depending on E85's current price discount relative to the current price of gasoline. As described earlier, the best thing for drivers to do is to record fuel usage with both fuels and calculate cost/distance for them. Only by doing that, can the end-user economy of the two fuels be compared.

For example, an existing pre-2003 model year American-made FFV vehicle that normally achieves, say, 30 MPG on pure gasoline will typically achieve about 20 MPG, or slightly better, on E85 (summer blend.) When operated on E85 winter blend, which is actually E70 (70% ethanol, 30% gasoline), fuel economy will be higher than when operating on the summer blend. To achieve any short-term operational fuel cost savings, the price of E85 should therefore be 30% or more below the price of gasoline to equalize short term fuel costs for most older pre-2003 FFVs for both winter and summer blends of E85. Life-cycle costs over the life of the FFV engine are theoretically lower for E85, as ethanol is a cooler and cleaner burning fuel than gasoline. Provided that one takes a longterm life-cycle operating cost view, a continuous price discount of only 20% to 25% below the cost of gasoline is probably about the break-even point in terms of vehicle life-cycle operating costs for operating most FFVs on E85 exclusively (for summer, spring/fall, and winter blends).

Fuel economy in fuel-injected non-FFVs operating on a mix of E85 and gasoline varies greatly depending on the engine and fuel mix. For a 60:40 blend of gasoline to E85 (summer blend), a typical fuel economy reduction of around 23.7% resulted in one person's carefully executed experiment with a 1998 Chevrolet S10 pickup with a 2.2L 4-cylinder engine, relative to the fuel economy achieved on pure gasoline. Similarly, for a 50:50 blend of gasoline to E85 (summer blend), a typical fuel economy reduction of around 25% resulted for the same vehicle. (Fuel economy performance numbers were measured on a fixed commute of approximately 110 miles roundtrip per day, on a predominantly freeway commute, running at a fixed speed (62 mph), with cruise control activated, air conditioning ON, at sea level, with flat terrain, traveling to/from Kennedy Space Center, FL.). It is important to note, however, that if the engine had been specifically tuned for consumption of ethanol (higher compression, different fuel-air mixture, etc.) the mileage would have been much better than the results above. The aforementioned fact leads some to believe that the "FFV" engine is more of an infant technology rather than fully mature.

The amount of reduction in mileage, therefore, is highly dependent upon the particulars of the vehicle design, exact composition of the ethanol-gasoline blend and state of engine tune (fuel air mixture and compression ratio primarily).

Use in flexible-fuel vehicles

E-85 ethanol is used in engines modified to accept higher concentrations of ethanol. Such flexible-fuel vehicles (FFV) are designed to run on any mixture of gasoline or ethanol with up to 85% ethanol by volume. There are a few major differences between FFVs and non-FFVs. One is the elimination of bare magnesium, aluminum, and rubber parts in the fuel system. Another is that fuel pumps must be capable of operating with electrically conductive ethanol instead of non-conducting dielectric gasoline fuel. Fuel injection control systems have a wider range of pulse widths to inject approximately 40% more fuel. Stainless steel fuel lines, sometimes lined with plastic, and stainless steel fuel tanks in place of terne fuel tanks are used. In some cases, FFVs use 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.

Comparisons to regular gasoline

See also: E85 in standard engines
E85 fuel dispenser at a regular gasoline station.

E85 has an octane rating higher than that of regular gasoline's typical rating of 87, or premium gasoline's 91-93. This allows it to be used in higher compression engines which tend to produce more power per unit of displacement than their gasoline counterparts. The Renewable Fuels Foundation states in its Changes in Gasoline IV manual, "There is no requirement to post octane on an E85 dispenser. If a retailer chooses to post octane, they should be aware that the often cited 105 octane is incorrect. This number was derived by using ethanol’s blending octane value in gasoline. This is not the proper way to calculate the octane of E85. Ethanol’s true octane value should be used to calculate E85’s octane value. This results in an octane range of 94-96 (R+M)/2. These calculations have been confirmed by actual octane engine tests." [6]

One complication is that use of gasoline in an engine with a high enough compression ratio to use E85 efficiently would likely result in catastrophic failure due to engine detonation, as the octane rating of gasoline is not high enough to withstand the greater compression ratios in use in an engine specifically designed to run on E85. Use of E85 in an engine designed specifically for gasoline would result in a loss of the potential efficiency that it is possible to gain with this fuel. Using E85 in a gasoline engine has the drawback of achieving lower fuel economy as more fuel is needed per unit air (stoichiel ratio) to run the engine in comparison with gasoline. This corresponds to a lower heating value (units of energy per unit mass) for E85 than gasoline. Some vehicles can actually be converted to use E85 despite not being specifically built for it. Because of the lower heating value E85 has a cooler intake charge, which coupled with its high stability level from its high octane rating, has also been used as a "power adder" in turbocharged performance vehicles. These modifications have not only resulted in lower GHG emissions, but also resulted in 10-12% horsepower and torque increase at the wheels. Because of its low price (less than $2.00/gal in some places) and high availability in certain areas people have started to turn to using it in place of the high end race fuels that typically cost over $10.00/gal.

E85 consumes more fuel in flex fuel type vehicles when the vehicle uses the same compression for both E85 and gasoline because of its lower stoichiometric fuel ratio and lower heating value. European car maker Saab currently produces a flex fuel version of their 9-5 sedan which consumes the same amount of fuel whether running e85 or gasoline,[7] though it is not available in the United States. So in order to save money at the pump with current flex fuel vehicles available in the United States the price of E85 must be much lower than gasoline. Currently E85 is about 15% less expensive in most areas.[8] More than 20 fueling stations across the Midwest are selling E85 at the same price as gasoline.[9] E85 also gets less MPG, at least in flex fuel vehicles. In one test, a Chevy Tahoe flex-fuel vehicle averaged 18 MPG [U.S. gallons] for gasoline, and 13 MPG for E85, or 28% fewer MPG than gasoline. In that test, the cost of gas averaged $3.42, while the cost for E85 averaged $3.09, or 90% the cost of gasoline.[10][11] In another test, however, a fleet of Ford Tauruses averaged only about 6% fewer miles per gallon in the ethanol-based vehicles as compared to traditional, gas-powered Tauruses.[12] (Please note this is questionable as the reference provided is non-existent on NREL's website.)

In the United States

Main article: E85 in the United States
See also: Corn ethanol

As of December 31, 2008, there were about 1,921 public E85 fueling stations available in the United States.[13] Prices vary by location, some prices over 30% less than regular gasoline. In other places it has been more expensive.

A recent development in the expansion of E85 filling stations is Wal-Mart's announcement that it will possibly sell E85 at its 385 gas stations countrywide. Wal-Mart along with its popular division, Sam's Club has a partnership with Murphy Oil Corp. which operates more than 9,000 gas stations in Wal-Mart parking lots. Should they decide to follow through with plans, Wal-mart has the potential to be the single largest retailer of E85 in the nation.[14] Grocery retailers in Texas are also beginning to sell E85 at some fuel stations.[15][16]

EPA's stringent tier II vehicle emission standards require that FFVs achieve the same low emissions level regardless of whether E85 or gasoline is used. However, E85 can further reduce emissions of certain pollutants as compared to conventional gasoline or lower volume ethanol blends. For example, E85 is less volatile than gasoline or low volume ethanol blends, which results in fewer evaporative emissions. Using E85 also reduces carbon monoxide emissions and provides significant reductions in emissions of many harmful toxics, including benzene, a known human carcinogen. However, E85 also increases emissions of acetaldehyde. EPA is conducting additional analysis to expand our understanding of the emissions impacts of E85.[17]

Production

In July 2006 Goldman Sachs invested $27 million into a Canadian company called Iogen, which wants to produce ethanol from switchgrass, a perennial grass that is inexpensive to grow. Iogen, a non-publicly traded company, is building the world's first full-scale commercial cellulose-to-ethanol plant by 2010. Another reason for ethanol's popularity is its contribution toward providing economic revitalization in rural communities across the country.[18]

The U.S. Congress passed The Energy Independence and Security Act of 2007, which mandates an increase in the use of biofuels in a new Renewable Fuel Standard (RFS), including ethanol, through the year 2022.[19]

See also

Notes

  1. ^ Nerad, J. (2007) The Complete Idiot's Guide to Hybrid and Alternative Fuel Vehicles. Penguin Group, NY.
  2. ^ "Virginia E85 Station Pushes National Locations Over 1,900". Domestic Fuel Alternative Fuel News. 2009-01-07. {{cite news}}: Cite has empty unknown parameter: |coauthors= (help)
  3. ^ "Canada Advancing E85". National Ethanol Vehicle Coalition Newsletter. 2003-01-15. {{cite news}}: Cite has empty unknown parameter: |coauthors= (help)
  4. ^ Brent, Paul (2007-02-14). "Canada helps GM clean its fleet". National Post. {{cite news}}: Cite has empty unknown parameter: |coauthors= (help)
  5. ^ "Maxol Bioethanol E85 leaflet" (PDF). Retrieved 2010-12-05.
  6. ^ Changes in Gasoline IV, sponsored by Renewable Fuels Foundation
  7. ^ Liquor Does It Quicker, Matthew Phenix, Popular Science. Retrieved April 29, 2008.
  8. ^ Wiesenfelder, Joe. "Fuel Economy | Gas Alternatives". Cars.com. Retrieved 2010-12-05.
  9. ^ "E85 Prices". E85 Prices. Retrieved 2010-12-05.
  10. ^ "E85 vs Gasoline Comparison test". Edmunds.com. Retrieved 2010-12-05.
  11. ^ "Ethanol: The facts, the questions | desmoinesregister.com". The Des Moines Register. Retrieved 2010-04-04.
  12. ^ [1][dead link]
  13. ^ "E85 Prices". E85 Prices. Retrieved 2010-04-04.
  14. ^ E85 at Club Rate. Retrieved September 17, 2007.
  15. ^ Kroger stores are selling E85 at fuel stations nationwide expanding outward from Houston, and Dallas, Texas. Retrieved September 17, 2007.
  16. ^ HEB stores are also offering E85 at some fuel stations in the Texas Hill Country. Retrieved September 17, 2007.
  17. ^ [2][dead link]
  18. ^ "Iogen gets boost from Goldman Sachs". Iogen.ca. 2006-05-01. Retrieved 2010-12-05.
  19. ^ "Biomass Program: Federal Biomass Policy". .eere.energy.gov. Retrieved 2010-04-04.

References

  • US Department of Energy

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

  • Center for American Progress

Flex-Fuel Bait and Switch - See how many flex-fuel cars are on the road and how many stations offer E85.

Retrieved from "https://en.wikipedia.org/w/index.php?title=E85&oldid=401275309"