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A high-octane, water-free alcohol produced from the fermentation
of sugar or converted starch. In its purest form it is a colorless
clear liquid with mild characteristic odor that boils at 78oC and
freezes at 112oC. It has no basic or acidic combustion engines either
on its own or blended with petroleum. Hydrous bioethanol (95% purity)
is used for blending with gasoline.
STANDARDS
The Department of Trade and Industry-Bureau of Products Standard,
the Department of Energy in cooperation of private sectors developed
and promulgated standards for the bioethanol program to ensure the
fuel quality.
Facts on Fuel Ethanol
What is fuel ethanol?
Fuel ethanol is a high-octane, water free alcohol produced from
the fermentation of sugar or converted starch.
It is traditional used as a blending ingredient at 5%-10% concentrations
in gasoline or as a raw material to produce high-octane fuel ether
additives. Ethanol is made primarily from sugarcane, corn, wheat,
sorghum, and other feedstocks. In the Philippines, sugarcane is
the most readily available feedstock. Cassava and sweet sorghum
are also potential feedstocks.
Why fuel ethanol?
Technical feasibility
Fuel ethanol makes an ideal motor fuel for spark ignition
engines for many reasons:
Ethanol has a high natural 'octane' rating that prevents premature
detonation under load
Ethanol burns more cleanly because it contains oxygen, hence less
carbon monoxide emissions
Ethanol burns slightly cooler, extending engine life
Ethanol has a higher 'volumetric efficiency'- contributes to increased
power
Most modern gasoline vehicles could operate on pure ethanol with
a few basic engine modifications. A 10% blend requires no engine
modification while making a contribution to reducing emissions.
Anything more than 10% requires engine modification. In North
America, Flexible Fuel Vehicles (FFV) are currently available
that will operate on blends of up to 85% ethanol with gasoline
(called E85). Brazil uses a 24% blend.
Ethanol up to 190 proof (95% strength) can be produced using
simple distillation. Removal of the last 5% water from an ethanol
solution requires more complex methods. Hydrous (water containing)
ethanol can be used neat (at 100% rate) in a modified gasoline
engine, as they do in Brazil. If the ethanol is to be blended
with gasoline at any rate, the ethanol must be completely anhydrous
(dry) - 200 proof. Otherwise, separation of the fuels will occur.
Renewability
Ethanol is a renewable fuel source. It is produced from plants
that process and store energy from the sun. In a sustainable cropping
system, plant feedstock can be produced year after year. Regions
of the world that are without crude oil deposits could consider
'fuel farming' as a long-term solution to offset their energy
needs and foreign oil dependency.
Environmental benefit
Pure alcohol fuel, such as ethanol, has nearly complete combustion.
This means that very little carbon monoxide is formed. Alcohol
does not contain contaminants commonly found in gasoline such
as sulfur and benzene. Compared to gasoline, harmful emissions
and pollution are greatly reduced. When blended with gasoline,
ethanol contributes a reduction in most emissions according to
its percentage in the blend.
Economic benefit
Fuel ethanol expands the market for Filipino farmers, particularly
the sugar sector, thus enhancing rural economic development.
Fuel economy
Changes in fuel economy are minimal. While a 10% 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-blends have said their fuel economy
has improved.
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