| What is Ethanol?
Ethanol is ethyl alcohol. It is a product of the fermentation of any plant material, whether sugar-, starch-, or cellulose-based. Ethanol is the same alcohol as in alcoholic beverages. Ethanol makes an excellent fuel for internal combustion engines (ICE’s) with spark ignition.
Why Ethanol?
Technical feasibility
Alcohol makes an ideal motor fuel for spark ignition engines for many reasons:
- Alcohol has a high natural ‘octane’ rating - prevents premature detonation under load
- Alcohol burns more cleanly because it contains oxygen - less carbon monoxide emissions
- Alcohol burns slightly cooler - extends engine life
- Alcohol has a higher ‘volumetric efficiency’- contributes to increased power
Most modern gasoline vehicles could operate on pure ethanol with a few basic engine modifications. As well, any gasoline engine can run on commercial blends of up to 15 - 20% (depending on the vehicle) ethanol with gasoline without modifications. In North America, Flexible Fuel Vehicles (FFV) are currently available that will operate on blends of up to 85% ethanol with gasoline (called E85).
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. 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.
Cost effectiveness
The cost of commercial ethanol production from grain is currently about $0.35 to $0.45/litre. Real costs of individual/farm ethanol production vary with the size and level of automation of the process equipment. Other factors include cost of feedstock, process energy requirements, bulk handling considerations, final use (i.e., as straight or blended fuel), possibility of integration with other farm operations (i.e., feedlot), time and management requirements.
What are Some Problems with Ethanol?
A popular argument against ethanol is that it is not Net Energy Positive. However, many recent studies show ethanol to have a positive energy balance. This means in considering the life cycle of ethanol, including byproducts from its production, more energy is contained in ethanol than is used to produce it. Depending on the production system used for growing and producing ethanol, the energy return presently can vary from 1.24:1 to 2.09:1.
Ethanol needs to absorb a certain amount of heat to be effectively vaporized for use in an engine. Once an engine has reached the operating temperature, this vaporization occurs as required. However, there are performance issues with cold weather starting. FFV produced for the North American market incorporate various technologies to improve the cold-start performance using ethanol. Gasoline engines retrofitted to use ethanol would require additional modifications to be cold weather reliable. This might include an in-line fuel heater or other pre-heat strategies.
When ethanol is blended with gasoline, it has the potential to increase the volatility of gasoline. High volatility gasoline has higher emissions that contribute to increased smog formation. It is the gasoline emissions that are creating the smog, however, it is ethanol that raises the volatility of the gasoline blend. In Canada, gasoline volatility is closely regulated. Commercial blends of ethanol and gasoline cannot have higher volatility than unblended gasoline, therefore, there is no increase in smog-forming emissions due to ethanol blended fuel in Canada.
Small scale production of ethanol requires a significant input of equipment and labour. There is added cost to process the alcohol to the required 200 proof for blending with gasoline for unmodified engines. To be most effective, the ethanol should be used in modified engines. There are various costs associated with modifying a gasoline engine, depending on the engine.
Where Can I Obtain Ethanol?
In Canada, fuel ethanol blends are available at most gasoline retailers. At present, fuel ethanol is most commonly sold as blends of 5% or 10%. Fuel ethanol could be produced by individuals with home distillation equipment. Fuel taxes may need to be remitted according to provincial and federal regulations.
For more information
Kelly Lund , E.I.T.
#306, 7000 - 113 Street
Edmonton, Alberta T6H 5T6
Phone: 780-644-1197
Fax: 780-422-9745 |