THE FUTURE
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and biodiesel seem to be the most feasible ones at present. The key
advantage of bioethanol and biodiesel is that they can be mixed
with conventional petrol and diesel respectively, which allows
using the same handling and distribution infrastructure. Another
important strong point of bioethanol and biodiesel is that when
they are mixed at low concentrations (<10% bioethanol in petrol
and <20% biodiesel in diesel, no engine modifications are necessary.
Ethanol can be blended with gasoline to create E85, a blend of 85%
ethanol and 15% gasoline. E85 and blends with even higher concentrations of ethanol, E95, include pure bioethanol (ElOO-fuel), which
has been used mainly in Brazil (Davis, 2006; Minteer, 2006; Speight,
2008). More widespread practice has been to add up to 20% to gasoline (E20-fuel or gasohol) to avoid engine changes. However, E100fueled vehicles have difficulty starting in cold weather, but this is
not a problem for E85 vehicles because of the presence of gasoline.
In comparison to gasoline, ethanol contains 35% oxygen by
weight; gasoline contains none. The presence of the oxygen promotes more complete combustion, which results in fewer tailpipe
emissions. Compared to the combustion of gasoline, the combustion of ethanol substantially reduces the emission of carbon monoxide, volatile organic compounds, particulate matter and green
house gases. However, a unit of ethanol contains about 32% less
energy than a unit of gasoline. One of the best qualities of ethanol
is its octane rating.
Biodiesel is the generic name for fuels obtained by esterification (by methanol or by ethanol) of vegetable oil (Knothe et al.,
2005; Bockey, 2006). Biodiesel can be used in a diesel engine
without modification and is a clean burning alternative fuel produced from domestic, renewable resources. The fuel is a mixture
of fatty acid alkyl esters made from vegetable oils, animal fats
or recycled greases. Where available, biodiesel can be used in
compression-ignition (diesel) engines in its pure form with little or
no modifications.
Biodiesel is biodegradable, nontoxic, and essentially free of sulfur
and aromatics. It is usually used as a petroleum diesel additive to
reduce levels of particulates, carbon monoxide, hydrocarbons, and
air toxics from diesel-powered vehicles. When used as an additive,
the resulting diesel fuel may be called B5, BIO or B20, representing
the percentage of the biodiesel that is blended with petroleum diesel.
Biodiesel is produced through a process in which organic
oils, such as soybean oil or recycled cooking oil, are combined
263
and biodiesel seem to be the most feasible ones at present. The key
advantage of bioethanol and biodiesel is that they can be mixed
with conventional petrol and diesel respectively, which allows
using the same handling and distribution infrastructure. Another
important strong point of bioethanol and biodiesel is that when
they are mixed at low concentrations (<10% bioethanol in petrol
and <20% biodiesel in diesel, no engine modifications are necessary.
Ethanol can be blended with gasoline to create E85, a blend of 85%
ethanol and 15% gasoline. E85 and blends with even higher concentrations of ethanol, E95, include pure bioethanol (ElOO-fuel), which
has been used mainly in Brazil (Davis, 2006; Minteer, 2006; Speight,
2008). More widespread practice has been to add up to 20% to gasoline (E20-fuel or gasohol) to avoid engine changes. However, E100fueled vehicles have difficulty starting in cold weather, but this is
not a problem for E85 vehicles because of the presence of gasoline.
In comparison to gasoline, ethanol contains 35% oxygen by
weight; gasoline contains none. The presence of the oxygen promotes more complete combustion, which results in fewer tailpipe
emissions. Compared to the combustion of gasoline, the combustion of ethanol substantially reduces the emission of carbon monoxide, volatile organic compounds, particulate matter and green
house gases. However, a unit of ethanol contains about 32% less
energy than a unit of gasoline. One of the best qualities of ethanol
is its octane rating.
Biodiesel is the generic name for fuels obtained by esterification (by methanol or by ethanol) of vegetable oil (Knothe et al.,
2005; Bockey, 2006). Biodiesel can be used in a diesel engine
without modification and is a clean burning alternative fuel produced from domestic, renewable resources. The fuel is a mixture
of fatty acid alkyl esters made from vegetable oils, animal fats
or recycled greases. Where available, biodiesel can be used in
compression-ignition (diesel) engines in its pure form with little or
no modifications.
Biodiesel is biodegradable, nontoxic, and essentially free of sulfur
and aromatics. It is usually used as a petroleum diesel additive to
reduce levels of particulates, carbon monoxide, hydrocarbons, and
air toxics from diesel-powered vehicles. When used as an additive,
the resulting diesel fuel may be called B5, BIO or B20, representing
the percentage of the biodiesel that is blended with petroleum diesel.
Biodiesel is produced through a process in which organic
oils, such as soybean oil or recycled cooking oil, are combined