CATEGORII DOCUMENTE |
Bulgara | Ceha slovaca | Croata | Engleza | Estona | Finlandeza | Franceza |
Germana | Italiana | Letona | Lituaniana | Maghiara | Olandeza | Poloneza |
Sarba | Slovena | Spaniola | Suedeza | Turca | Ucraineana |
Alternative Fuels
Alternative Fuel Vehicles You Can Buy Today
From the earliest days of the automotive industry alternative fuels have always
competed with petroleum for powering vehicles. Nicholas Cugnot
made the first self-powered road vehicle in 1769 with a steam engine, and the
first gasoline automobile didn't appear until over 100 years later from Karl
Benz. Through the late 19th and early 20th century steam and electric power
remained strong contenders. The invention of the self-starter for gasoline engines
by Cadillac eventually proved the undoing of the early steam cars, which
required warming up. Electric cars continued to be produced for a while longer,
but the expanding road network gradually made their short range of 8-15 miles
between charges too inconvenient for many uses.
Today we understand that the wholesale burning of petroleum can't continue
forever. As the new century opens alternative fuel vehicles are becoming more
and more common. Major manufacturers such as Ford, Daimler/Chrysler, and Fiat
offer dual fuel cars and trucks now. These vehicles allow you to choose between
gasoline and compressed natural gas (CNG) for cleaner emissions. Other large
manufacturers such as General Motors, Toyota, and Honda are concentrating on
electric vehicles. These global automakers are slowly
moving from conventional to alternative power as the technology is developed
and refined. Current battery technology allows a maximum range of about 125
miles per charge.
The leading edge of electric vehicle technology is occupied by much smaller
companies. Bombardier, Pivco AS, and S-LEM AG have
designed small, lightweight city cars intended for daily use in dense urban
environments. Corbin-Pacific and Zebra Motors have
chosen to concentrate on performance. Both companies produce creditable sports
cars that just happen to be electrically powered.
Do you have an idea that you think will work for an alternatively powered
vehicle concept? The U.S. Department of Energy invites small businesses (500
employees or less) to submit grant applications on hybrid electric vehicle
technology. Applicants may receive up to $75,000 US for a Phase I grant to
develop the feasibility of the idea.
Hydrogen Vehicles
Fuel Description
Hydrogen is the most abundant element in the universe, but is rarely found in
its uncombined form on the earth. When combusted (oxidized) it creates only
water vapor as a by-product (4H + O2 = 2 H20). When burned in an internal
combustion engine, however, combustion also produces small amounts of nitrogen
oxides and small amounts of unburned hydrocarbons and carbon monoxide because
of engine lubricants. The exhaust is free from carbon dioxide.
Hydrogen is normally a gas and can be compressed and stored in cylinders. It
can also be kept as a liquid, but the gas only turns liquid at temperatures of
minus 423.2 degrees Fahrenheit (below zero)!
Today, hydrogen is mostly obtained by cracking hydrocarbon fuels, but it can be
produced by electrolysis of water (using electricity to split water into
hydrogen and oxygen) and photolysis (chemical
decomposition). The main problem with hydrogen is bulk storage required for
fuel tanks.
For an equivalent energy content of gasoline, liquid hydrogen and the required
refrigeration system requires six to eight times more storage space than
gasoline and compressed hydrogen gas requires six to ten times more storage
space.
Another development using hydrogen is as a blend of hydrogen and methane
(natural gas) called Hythane. Preliminary information
presented in mid- 1994 at the 10th World Hydrogen Energy Conference in Cocoa
Beach, Florida, says that a test car's exhaust using 30 percent hydrogen and 70
percent methane contained 80 percent less nitrogen oxides than U.S. EPA
standards for 2003. This blend has much higher content of hydrogen than other Hythane blends, which typically run about five percent. To
learn more about hydrogen go to the Hydrogen Fuel Page.
Vehicle Availability
There are no vehicles currently available that use hydrogen as a fuel; however,
automobile manufacturers have experimented with developing vehicles that use
hydrogen. Research vehicles have been produced by Daimler-Benz, BMW and Mazda.
The Mercedes-Benz and BMW vehicles use liquid hydrogen. The Mazda vehicle
stores its hydrogen as a gas in a metal-hydride lattice of shaved metal. Other
vehicles have been built using compressed hydrogen, including two vehicles in
Arizona operated by the American Hydrogen Association.
High production costs and low density have prevented hydrogen's use as a
transportation fuel in all but test programs. It may be 20 to 30 years or more
before hydrogen is a viable transportation fuel and then perhaps only in
fuel-cell-powered vehicles.
What is Ethanol?
Ethanol (ethyl alcohol, grain alcohol, ETOH) is a clear, colorless liquid with
a characteristic, agreeable odor. In dilute aqueous solution, it has a somewhat
sweet flavor, but in more concentrated solutions it has a burning taste.
Ethanol, CH3CH2OH, is an alcohol, a group of chemical compounds whose molecules
contain a hydroxyl group, -OH, bonded to a carbon atom.
Two higher blends of ethanol, E-85 and E-95 are being explored as alternative
fuels in demonstration programs. Ethanol is also made into an ether, ethyltertiary-butyl ether (ETBE), that has properties of
interest for oxygenated gasoline and reformulated fuels.
Chemical Properties: Ethanol is ethane with a hydrogen molecule replaced by a
hydroxyl radical. See the fuel properties table (PDF: 116 KB) for more
information.
How is Ethanol Made?
There are basically eight steps in the ethanol production process:
1. Milling: The corn (or barley or wheat) will first pass through hammer mills,
which grind it into a fine powder called meal.
2. Liquefaction: The meal will then be mixed with water and alpha-amylase, and
will pass through cookers where the starch is liquefied. Heat will be applied
at this stage to enable liquefaction. Cookers with a high temperature stage
(120-150 degrees Celsius) and a lower Temperature-holding period (95 degrees
Celsius) will be used. These high temperatures reduce bacteria levels in the
mash.
3. Saccharification: The mash from the cookers will
then be cooled and the secondary enzyme (gluco-amylase)
will be added to convert the liquefied starch to fermentable sugars (dextrose),
a process called saccharification.
4. Fermentation: Yeast will then be added to the mash to ferment the sugars to
ethanol and carbon dioxide. Using a continuous process, the fermenting mash
will be allowed to flow, or cascade, through several fermenters
until the mash is fully fermented and then leaves the final tank. In a batch
fermentation process, the mash stays in one fermenter
for about 48 hours before the distillation process is started.
5. Distillation: The fermented mash, now called 'beer,' will contain
about 10% alcohol, as well as all the non-fermentable solids from the corn and
the yeast cells. The mash will then be pumped to the continuous flow,
multi-column distillation system where the alcohol will be removed from the
solids and the water. The alcohol will leave the top of the final column at
about 96% strength, and the residue mash, called stillage,
will be transferred from the base of the column to the co-product processing
area.
6. Dehydration: The alcohol from the top of the column will then pass through a
dehydration system where the remaining water will be removed. Most ethanol
plants use a molecular sieve to capture the last bit of water in the ethanol.
The alcohol product at this stage is called anhydrous (pure, without water)
ethanol and is approximately 200 proof.
7. Denaturing: Ethanol that will be used for fuel is then denatured with a
small amount (2-5%) of some product, like gasoline, to make it unfit for human
consumption.
8. Co-Products: There are two main co-products created in the production of
ethanol: carbon dioxide and distillers grain. Carbon dioxide is given off in
great quantities during fermentation and many ethanol plants collect that
carbon dioxide, clean it of any residual alcohol, compress it and sell it for
use to carbonate beverages or in the flash freezing of meat. Distillers grains,
wet and dried, are high in protein and other nutrients and are a highly valued
livestock feed ingredient. Some ethanol plants also create a 'syrup'
containing some of the solids that can be a separate production sold in
addition to the distiller's grain, or combined with it. Ethanol production is a
no-waste process that adds value to the corn by converting it into more
valuable products.
Ethanol is also made from a wet-milling process. Many of the larger ethanol
producers use this process, which also yields many other products, such as high
fructose corn sweetner.
Ethanol Market
Ethanol will probably be transferred from import terminals or production
facilities by barge, rail, or truck to eventually reach retail outlets. While
the alcohols are liquids at ambient temperatures and
atmospheric pressures, they cannot be moved easily through the existing
petroleum product network to end-users.
Ethanol is already penetrating the transportation market through gasohol.
Although an exact figure is not available, there are many gasohol outlets.
However, ethanol used in gasohol is not an alternative fuel as defined by EPAct--It is a replacement fuel. Since E-85 is not being
widely used, and E-95 is only undergoing demonstration, few outlets for these
alternative fuels are currently available.
To learn more about ethanol vehicles and to see which ethanol vehicles are
available for sale or lease, go to the AFDC Ethanol Vehicle Page.
Benefits
In general, the benefits to using ethanol are:
? Reducing the need for foreign oil
? Preventing air pollution by using a low emission vehicle
? Using a renewable fuel
For more detailed information on ethanol benefits, go to the American Coalition
for Ethanol Web Page.
FAQs
Please go to the:
? Ethanol Information Centre's FAQs
Page
? The California Energy Commission's FAQ page
If you have further questions regarding Ethanol, please call the National
Alternative Fuels Hotline (800) 423-1DOE.
Background
The concept of ethanol as a fuel began as early as the first Model T car
designed by Henry Ford. American usage of ethanol-blended gasoline began in the
late 1970s. Environmentally, the use of ethanol blends has assisted in reducing
carbon monoxide emissions as mandated by the U.S. Clean Air Act of 1990. In
addition, as corn prices declined during the 1980s, ethanol production, using
corn as a feedstock, came to be seen as a way of expanding the domestic market
for grain, helping to stabilize farmers' incomes.
In Canada, air quality issues have taken on a higher profile on the public
agenda. For agriculture, the savings in government spending on farm support
programs in Canada have not been as evident as in the U.S. Consequently, until
recently, fuel ethanol has not received the level of public attention and
private investment as it has in the U.S.
What is fuel ethanol?
Fuel ethanol (or 'Gasohol') is a high octane, water-free alcohol produced from
the fermentation of sugar or converted starch. It is traditionally used as a
blending ingredient at 5% to 10% concentrations (termed E5 or E10,
respectively) in gasoline or as a raw material to produce high octane fuel
ether additives. Ethanol is made primarily from grains or other renewable
agricultural and agroforestry feedstocks.
What are the advantages to using ethanol-blended fuels?
? Renewable
? Cleaner environment
? Cleaner burning engines
? Lower net carbon dioxide emissions
? Less dependence on imported light crude oil
? Expanded market opportunity for Canadian farmers
? Economic opportunities for rural Canada
How does the use of ethanol-blended fuel benefit the environment?
Net Reduction in Ground Level Ozone-Forming Emissions
Ground-level ozone causes human respiratory problems and damages many plants,
but does nothing to increase ozone concentration in the stratosphere that
protects the earth from the sun's ultraviolet radiation.
In Canada, where the volatility of ethanol blends must match normal gasoline,
the ozone forming potential of ethanol blends is even lower than in the U.S.,
where ethanol blends are allowed to have increased volatility. The emissions
produced by burning ethanol are less reactive with sunlight than those produced
by burning gasoline. This results in a lower potential for forming the damaging
ozone.
The Greenhouse Effect
The 'Greenhouse Effect' refers to the Earth's atmosphere trapping the sun's
radiation. It is a term often used synonymously with 'Global Warming', which
refers to the increasing average global temperature, arising from an increase
in greenhouse gases from industrial activity and population growth. Greenhouse
gases contributing to the Greenhouse Effect include carbon dioxide, methane,
and nitrous oxide.
The term 'Climate Change' refers to a wide range of changes in weather patterns
that result from global warming. A substantial increase in the Earth's average
temperature could result in a change in agricultural patterns and melting of
polar ice caps, raising sea levels and causing flooding of low-lying coastal
areas. Use of ethanol fuels has been shown to reduce emissions that contribute
to global warming by 35-36%.
30% Reduction in Carbon Monoxide (CO) Emissions
Carbon monoxide is a toxic gas that contributes to air pollution. It is of
particular concern when vehicles are operating at lower temperatures.
Oxygenated gasolines, such as ethanol blends, lower
the levels of CO emitted, by promoting a more complete combustion of the fuel.
6% to 10% Net Reduction in Carbon Dioxide (CO2) Entering the Atmosphere
Carbon dioxide is a normal product of burning fuels that contributes to global
warming. More CO2 is absorbed by crop growth than is released by manufacturing
and using ethanol.
'Environmental ChoiceTM'
The environmentally beneficial attributes of ethanol-blended gasoline have
resulted in its designation as an 'Environmental ChoiceTM'
product, displaying the 'EcoLogoTM' at
licensed retail outlets.
What are the environmental implications of feedstock production associated with
the production of ethanol for fuel?
Biological Renewability
Fuel ethanol is produced from biologically renewable sources, such as grain or
wood products.
Sustainable Agriculture
With the development of sustainable and environmentally sensitive production
methods in the agricultural sector, the impact of farming practices is very
minimal. The demand for grain to produce fuel ethanol has not resulted in an
increased corn or wheat acreage in Canada.
What are the by-products/co-products of fuel ethanol production?
Flour, Corn Oil, Corn Meal, Corn Grits
Used in producing food for human consumption.
FibroteinTM
Used as a high fibre and protein food additive.
Corn Gluten Meal and Corn Gluten Feed
Used as high protein animal feed additives.
Amino Acids
Used as animal feed additives.
Dry Distiller's Grains
Used as high protein and energy animal feed.
Carbon Dioxide
Used as a refrigerant, in carbonated beverages, to help vegetable crops grow
more rapidly in greenhouses, and to flush oil wells.
How will fuel ethanol impact Canadian agriculture?
Market Opportunities
Fuel ethanol represents an important new market for Canadian grains.
Impact on exports
Ethanol production will not likely affect Canadian grain exports. If all
gasoline sold in Canada contained 10% ethanol made from Canadian grains, 8
million tonnes of grain would be used, compared to
current exports of 24 million tonnes, and current
production of 50 million tonnes. There will still be
a surplus for export.
Impact on grain prices
The prices of grains have historically moved in parallel with oil prices.
Distiller's grains and gluten feed are high-protein feeds that are co-products
produced from grains when starch is made into ethanol. Therefore, when the cost
of grain is high, a greater portion of the processor's costs can be recovered
through the sale of protein feeds.
Co-products
Distiller's grains, a co-product from ethanol production, will also impact the
availability of protein supplements for cattle and other ruminants, thereby
decreasing the demand for imported soybean meal. The potential also exists to
'partner' fuel ethanol plants with other agricultural operations,
such as the combined ethanol plant-cattle feedlot operation in Lanigan, Saskatchewan. Other agricultural partners could
include dairy operations, feed mills, grain elevators, greenhouses, mushroom
plants, and co-generation plants.
Can ethanol be produced from off-grade or damaged corn?
Yes. This is a good market for off-grade or damaged corn. As can be expected,
the price paid by the ethanol processor for the corn will be affected, as well
as the value of the distiller's grains.
What are alternative feedstocks for ethanol
production?
Currently, corn is the primary feedstock for ethanol production. In some areas
of the country, wheat and wood are also used. In the future, other agricultural
feedstocks and crop residues such as straw, stover, or corn cobs may be used to produce ethanol.
How much ethanol is produced from a bushel of corn or wheat?
The industry average is slightly more than 10 litres
per bushel in addition to the high protein livestock feeds and carbon dioxide
produced.
Why is fuel ethanol blended?
Brazil is able to operate nearly half of its cars on pure ethanol. Most engines
need some modification to run on pure ethanol. A 10% blend requires no engine
modification while making a contribution to reducing emissions.
How has the government responded to the production and use of
ethanol-blended fuels?
The Government of Canada has granted an excise tax exemption on the ethanol
portion of gasoline, as it is made from a renewable resource. Many Canadian
provinces also have provided for road tax exemptions. These tax exemptions
allow ethanol-blended fuels to be sold at a competitive price.
'FleetWise' is a federal initiative to address the
pollution caused by vehicle emissions and its effect on climate change. It
involves a gradual phased-in increase in use of alternative fuels, such as
ethanol. The Government of Canada has committed to integrating environmental
considerations and sound management practices in the operation of its motor
vehicles. This includes a phased-in acquisition of alternative fuel vehicles,
by the year 2005.
Is ethanol production energy efficient?
Ethanol contains about 32,000 (high heating value) BTUs per litre.
It takes about one fourth of that amount to grow the corn and about one third
of that amount to process the corn in a modern ethanol production facility.
Some of the processing costs should be allocated to the co-products that are
produced with the ethanol. If corn farmers use state-of-the-art, energy
efficient and sustainable farming techniques and ethanol plants integrate
state-of-the-art production processes, the amount of energy contained in the
ethanol and its co-products is more than twice the energy used to grow the corn
and convert it into ethanol.
How will using ethanol-blended fuels affect my vehicle?
What is the effect of using ethanol-blended fuels on the manufacturer's
warranty of my vehicle?
When the use of ethanol began in 1979, most automobile manufacturers did not
even address alcohol fuels. As soon as each manufacturer tested their vehicles,
they approved the use of a 10% ethanol blend. Today, all manufacturers approve
the use of 10% ethanol blends, and some even recommend it for environmental
reasons.
Is it necessary to make changes to my vehicle in order to use
ethanol-blended fuels?
All cars built since the 1970s are fully compatible with up to 10% ethanol in
the mixture.
Will ethanol-blended fuels work in fuel-injected engines?
Yes. It may be necessary to change the filter more frequently. Ethanol helps to
clean out the fuel-injection system, and may aid in the maintenance of a
cleaner engine.
Since 1985, all ethanol blends and nearly all non-ethanol gasolines
have contained detergent additives that are designed to prevent injector
deposits. These detergents have been very effective in addressing this issue.
Does ethanol in the fuel work as an effective gas line anti-freeze?
Gas line anti-freeze contains alcohol-usually methanol, ethanol, or isopropyl,
which can be used up to a 0.3% level in a car's fuel tank. All alcohols have the ability to absorb water, and therefore
condensation in the fuel system is absorbed and does not have the opportunity
to collect and freeze. If an ethanol blend contains 10% ethanol, it is able to
absorb more water than a small bottle of isopropyl, and eliminates the need and
expense of adding a gas line anti-freeze.
Will ethanol burn valves?
Ethanol will not burn engine valves. In fact, ethanol burns cooler than
gasoline. Ethanol high-powered racing engines use pure alcohol for that reason.
Will using ethanol-blended fuels plug the fuel filters in my vehicle?
Ethanol can loosen contaminants and residues that have been deposited by
previous gasoline fills. These can collect in the fuel filter. This problem has
happened occasionally in older cars, and can easily be corrected by changing
fuel filters.
Symptoms of a plugged fuel filter will be hesitation, missing, and a loss of
power. Once your car's fuel system is clean, you will notice improved
performance.
Can I mix fuels?
Yes. All gasolines in Canada (including low-level
ethanol blends) must meet the specifications of the Canadian General Standards
Board (CGSB). They are all interchangeable.
What is the effect of using ethanol-blended fuels on fuel economy?
Changes in fuel economy are minimal. While a 10% ethanol blend contains about
97% of the energy of 'pure' gasoline, this is compensated by the fact that the
combustion efficiency of the ethanol-blended fuel is increased. The net result
is that most consumers do not detect a difference in their fuel economy,
although many people using ethanol-blended fuels have said that their fuel
economy has improved.
Can ethanol-blended fuels be used in ATV's, chainsaws or other power or recreational
equipment?
Yes. An ethanol blend may be used anywhere that unleaded gasoline is used.
Farmers, cities, counties, and rural electric co-op fleets, plus snowmobile
racers and fishing guides in the U.S. use ethanol blends exclusively with no
performance problems. Adjustments may be required for air intake. It is
important to consult your owner's manual.
Is it safe to handle fuel ethanol blends?
The WHMIS Material Safety Data Sheet (MSDS) reveals that the properties of
ethanol blends are substantially the same as conventional gasoline blends.
Occupational health and safety risks presented by the use of ethanol gasoline
do not appear to be any different than those posed by conventional gasoline
blends.
Do ethanol blends need special handling or storage?
Only in special circumstances. The gasoline marketer should pump any
accumulated water from the storage tank, and add a final filter to the
dispensing hose. It is wise also to check seasonally used small engines such as
chainsaws and outboard motors (which are more susceptible to water
contamination) for the presence of water, and drain the tank if necessary.
What are the alternatives to ethanol as an oxygenate? How do they compare?
Methanol
Methanol is a derivative of natural gas. It is less expensive to produce than
ethanol but is highly corrosive, more volatile than ethanol, and more damaging
to plastic and rubber fuel system components (elastomers).
It also requires a co-solvent (usually ethanol). Ethanol provides better water
tolerance than methanol.
MTBE
MTBE (Methyl Tertiary Butyl Ether) is a high octane, low volatility, oxygenated
fuel component made by combining methanol and isobutylene
from oil refineries. It is not as sensitive to water as the alcohols,
and does not increase the volatility of most gasolines.
It is known to have a very distinct odor. It is non-corrosive and relatively
low-priced. It is currently the most widely used oxygenate, but is derived from
a non-renewable resource.
ETBE
ETBE (Ethyl Tertiary Butyl Ether) has properties similar to MTBE, but is
produced by combining ethanol (derived from a renewable resource) and isobutylene.
TAME and TAEE
TAME (Tertiary Amyl Methyl Ether) and TAEE (Tertiary Amyl Ethyl Ether) are
complex methyl and ethyl ethers, respectively. They are relatively new and have
similar characteristics to MTBE and ETBE.
How much fuel ethanol is being produced?
Canada's current annual ethanol production, for all markets (1998) is
approximately 234 million litres a year. With
additional proposed development of ethanol production plants, Canadian
potential production in the next few years is at 664 million litres per year.
How much fuel ethanol is being used?
It is difficult to ascertain current levels of fuel ethanol use in Canada. In
the U.S., it now represents about 9% of total gasoline sales, or the equivalent
of the total Canadian gasoline consumption. Over two trillion kilometres have been traveled using fuel ethanol blends.
Who produces alcohol?
? Mohawk Oil Canada Ltd., Minnedosa, Manitoba
(Capacity = 10 million litres);
? Pound-Maker Agventures, Ltd., Lanigan,
Saskatchewan (Capacity = 12 million litres);
? Commercial Alcohols Inc., Tiverton,
Ontario (Capacity = 23 million litres);
? Commercial Alcohols Inc., Chatham,
Ontario (Capacity = 150 million litres);
? Agri-Partners International, Inc. (API), Alberta
(Capacity = 22 million litres);
? Tembec, Temiscaming,
Quebec (Capacity = 17 million litres).
Additional proposed development of ethanol production plants includes those by
? Seaway Grain Processors, Inc., Cornwall, Ontario
(Capacity = 66 million litres);
? Commercial Alcohols, Inc., Varennes,
Quebec (Capacity = 150 million litres);
? Commercial Alcohols Inc.'s Chatham
plant plans to expand by another 150 million litres;
? Metalore Resources Inc. is continuing development
on a wheat-based ethanol production facility.
Who sells ethanol-blended fuels? Where can I purchase them?
Across Canada, there are approximately 950 retailers of ethanol-blended fuels
(July, 1998), excluding those who are not listed with the Canadian Renewable
Fuels Association.
Mohawk Oil is presently selling ethanol blends at over 290 stations in British
Columbia, Alberta, Saskatchewan, Manitoba, the Yukon and Northern Ontario.
Across southern Ontario, UPI Inc. retails ethanol blends at over 60 UPI Inc.,
FS and Co-op gasbars and cardlocks.
They are available in all grades of gasoline and for on-farm delivery. On
January 1, 1998, Sunoco Inc. launched ethanol-enhanced fuels at all its 275
retail outlets in Ontario. In eastern Ontario and western Quebec, MacEwen Petroleum Inc. is retailing ethanol blends at over
60 locations. Fuel ethanol retailing has expanded into Quebec with over 100
Sonic stations and other independent retail outlets. Other companies that have
joined in the retailing of ethanol-blended fuels include Mr. Gas, Pioneer
Petroleum, Frances Fuels, Stinson Petroleum and Sunys.
Politica de confidentialitate | Termeni si conditii de utilizare |
Vizualizari: 1136
Importanta:
Termeni si conditii de utilizare | Contact
© SCRIGROUP 2024 . All rights reserved