While the price at the pump for pure ethanol (E85) would be higher, an ethanol-gasoline blend (E10) probably wouldn't cost much more, if at all, than ordinary gasoline. After all, it's only 10% ethanol, not that big a deal in terms of price per gallon.

The most popular arguement against ethanol is whether or not there is a net energy gain. Ethanol production is becoming more efficient with time, especially in the last 10-15 years. Greater efficiency in fermentation and distillation means that for the same amount of ethanol it takes less energy to produce today. Energy returns of 0.85:1 are characteristic of refineries operating before 1980; energy returns of 1.24:1 were later realized between 1980-1992, and after that the use of lignin burning, and enzyme catalysts (cellulase, ligninase, etc.) further reduced energy consumption in the refining process to give energy returns of more than 2:1 for the same amount of fuel produced, depending on the feedstock. More research is being done today on the use of high-cellulose biomass (cellulose is the most abundant substance made by living things) such as sawdust, grasses, woodpulp, wheat straw, and saltwater seaweed. The high energy efficiency of modern refineries together with multiple feedstocks make ethanol an attractive replacement for fossil fuels.

Another popular argument against ethanol is it's cold-weather compatibility. 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. Flexible Fuel Vehicles 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. However for 10 percent ethanol-gasoline blends, I doubt there would be any cold-weather problems. After all, the gasoline would burn normally, and help to ignite the much smaller fraction of ethanol mixed with it. Also, if you don't live in a cold climate, such as the Canadian north, this problem won't affect you.

The third most popular argument against ethanol is the potential for increased smog. When ethanol is blended with gasoline, it will affect the chemical properties and has the potential to increase the volatility of the gasoline component. High volatility gasoline has higher emissions that contribute to increased smog formation. It is the gasoline emissions that are creating the smog, not the ethanol. 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 are required to maintain low volatility and cannot have higher volatility than unblended gasoline. Therefore, there is no increase in smog-forming emissions due to ethanol blended fuel in Canada. In other countries preventing this problem requires a simple tweak of the regulations.

There is nothing new about ethanol fuel: Henry Ford built the original Model-T to run on ethanol, and at that time saw ethanol as an enormous future prospect (before large deposits of oil were discovered). I recently found a book at Toronto Metro Reference Library published in 1907 and containing detailed information on how to modify a "dynamo" to run on ethanol, even how to make ethanol. The knowledge existed 95 years ago to do what we are seeing as wisdom today. 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).

Renewability
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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
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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
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Ethanol is the cheapest fuel next to gasoline.