The Alcohol Engine

If a 650 horsepower IndyCar Series race car can run on 100 percent ethanol, without compromising performance or safety, so can a personal automobile or truck. Forget any negative criticisms you may have heard about corn ethanol and listen to the truth—Alcohol is a better fuel than gasoline.

100% alcohol is a superior fuel for spark ignition internal combustion engines; but only if the engine is optimized to run on alcohol. The flex-fuel E-85 cars and trucks available today have gasoline engines that are not optimized to use alcohol.

“The Flex-Fuel Vehicles (FFVs) produced today, use fairly typical gasoline engines, which, because they must retain dual-fuel capability, are not able to take full advantage of the favorable combustion characteristics of alcohols.
“Engines optimized for alcohol fuel use, on the other hand, may yield efficiencies that exceed that of state-of-the-art diesel engines—or, about one third higher than that of FFV engines. In earlier engine research at EPA with neat [100%] methanol and ethanol, for example, over 40% brake thermal efficiency was achieved over a relatively broad range of loads and speeds, with peak levels reaching over 42%. Similar work has also been performed with E85, yielding up to 20% fuel economy improvement over baseline gasoline engines.”
Economical, High-Efficiency Engine Technologies for Alcohol Fuels   size: 134 Kb - 10 pages
— By Matthew Brusstar, U.S. EPA National Vehicle and Fuel Emissions Laboratory, and Marco Bakenhus, FEV Engine Technology, Inc.

Ethanol Engine efficiency exceeds gasoline engines, giving greater miles per gallon (MPG) with ethanol fuel:
High Efficiency and Low Emissions from a Port-Injected Engine with Alcohol Fuels
— By Matthew Brusstar, Mark Stuhldreher, David Swain and William Pidgeon, U.S. Environmental Protection Agency    size: 70 Kb - 7 pages

Ethyl alcohol in the early 20th century

The following excerpt is from a Paper to the American Society for Environmental History,  Annual Conference March 26-30, 2003 By William Kovarik, Ph.D.

“Studies of alcohol as an internal combustion engine fuel began in the U.S. with the Edison Electric Testing Laboratory and Columbia University in 1906. Elihu Thomson reported that despite a smaller heat or B.T.U. value, "a gallon of alcohol will develop substantially the same power in an internal combustion engine as a gallon of gasoline. This is owing to the superior efficiency of operation..." (New York Times Aug. 5, 1906) Other researchers confirmed the same phenomena around the same time.

“USDA tests in 1906 also demonstrated the efficiency of alcohol in engines and described how gasoline engines could be modified for higher power with pure alcohol fuel or for equivalent fuel consumption, depending on the need. The U.S. Geological Service (USGS) and the U.S. Navy performed 2000 tests on alcohol and gasoline engines in 1907 and 1908 in Norfolk, Va. and St. Louis, Mo. They found that much higher engine compression ratios could be achieved with alcohol than with gasoline. When the compression ratios were adjusted for each fuel, fuel economy was virtually equal despite the greater B.T.U. value of gasoline. "In regard to general cleanliness, such as absence of smoke and disagreeable odors, alcohol has many advantages over gasoline or kerosene as a fuel," the report said. "The exhaust from an alcohol engine is never clouded with a black or grayish smoke." USGS continued the comparative tests and later noted that alcohol was "a more ideal fuel than gasoline" with better efficiency despite the high cost.”

The gasoline engine became the preferred engine for the automobile because gasoline was cheaper than alcohol, not because it was a better fuel. And, because alcohol was not available at any price from 1920 to 1933, a period during which the sale, manufacture, and transportation of alcohol was banned nationally as mandated in the Eighteenth Amendment to the United States Constitution. The amendment was repealed by the Twenty-First Amendment on December 5, 1933. In time to produce alcohol fuels during World War II.

By the time World War II ended, the gasoline engine had become “entrenched” because gasoline remained cheaper than Alcohol, and widely distributed – gas stations were everywhere.

Then in 1973 through 1983, as in recent years, when dependence on foreign oil became a glaring national security issue and the price of gasoline soared, alcohol fuels were again in the national spotlight; but only to become bogged down in “Net Energy” and “Food vs. Fuel” arguments involving corn ethanol.

Synthetic alcohol will finally put to rest the “Net Energy” and “Food vs. Fuel” arguments.

Other arguments include the price of ethanol and the performance of alcohol fuels in an internal combustion engine. The IndyCar race cars should put to rest the engine performance argument and the price of gasoline is now far beyond the cost of synthetic ethanol. When the synthetic fuels industry reaches the size of the petroleum industry, synthetic ethanol should retail at about $2 per gallon.

One lingering argument — one that too many people just can't seem to let go of — involves the difference in BTU values between ethanol and gasoline: A gallon of gasoline has a much higher BTU value than a gallon of ethanol, which only has about 2/3 the BTU of gasoline.

BTU is an acronym for British Thermal Unit. One BTU equals the amount of heat energy required to increase the temperature of 1 pound of water by 1 degree Fahrenheit.

Conventional gasoline has about 116,000 BTU per gallon (LHV*). Ethanol has about 75,000 BTU per gallon (LHV). *LHV=Low Heating Value.  Gasoline's LHV should be compared with the LHV of Ethanol. Low heating values are based on the assumption that the energy in the exhaust water vapor cannot be used. This is true for cars. (For home heating the heat in the water vapor can be captured and used, so HHV* is appropriate. *HHV=High Heating Value.)

Ethanol opponents believe gasoline will always deliver better gas mileage than ethanol because gasoline has more BTU per gallon. The opponents say it is simply a matter of physics.

Ethanol proponents claim that ethanol will deliver equal or better gas mileage than gasoline, when ethanol is used to fuel an engine optimized to take advantage of ethanol’s superior combustion characteristics.

The BTU question, asks: “Will a gallon of ethanol deliver the same miles per gallon as a gallon of gasoline, if the weight of the two test vehicles is identical and the engine size and performance is the same, with the only difference being that one engine is optimized for gasoline and the other is optimized for alcohol?” (an Alcohol Engine)

Some people believe that if ethanol could get the same MPG as gasoline it would violate the laws of physics... and if the test was based on boiling water, it would violate the laws of physics — BTU is a measure of a fuels capacity to boil water.

If you are boiling water as an experiment to compare the energy value of the two fuels, and each experiment used identical furnaces, boilers and amount of water, then a gallon of gasoline would always boil more water than would a gallon of ethanol.

Consider this analogy of the BTU argument: Imagine a “shopping” experiment using two different people, where one person is given $116 and the other person is given $75 dollars. They are sent into the same Wal-Mart store at the same time on the same day (and the store manager agrees not to change prices while the shoppers are conducting the experiment). Each person spends all of the money given to them, and nothing more. Then we compare the receipts and see that one person purchased exactly $116 worth of products and the other person bought exactly $75 worth of products. There is the proof; $116 is worth more than $75. It is straight forward, just like boiling water.

But if we conduct the experiment in a different way, by giving the two people money to “invest” rather than “spend”, we can get a different result.

If one person is given $116,000 to invest and he or she finds an opportunity to earn a 25% return, then their “investment” would return [116,000 X .25 =] $29,000.

Now, if the other person is given only $75,000 to invest but places their money in a high-yield fund that earns 40%, then his or her “investment” would return [75,000 X .40 =] $30,000.

We see by this analogy that the “rate of return” is a very important factor in determining the value of an “investment”. The person who invested the $75,000 actually made more money than the person who had $116,000 to invest.

End of analogy and back to the subject: An Alcohol Engine offers much higher efficiency (rate of return) than does a gasoline engine.

You might ask, “why not use gasoline in the Alcohol Engine?” — Because gasoline would cause knocking in the high-compression alcohol engine. Knocking will damage the engine.

Because of the compression limitation required to prevent “engine knock”, a typical gasoline engine can only deliver about 25% efficiency — only 25% of the BTU's in a gallon of gasoline are converted to mechanical energy that turns the wheels of the car, the other 75% is lost in waste heat.

An Alcohol Engine can deliver about 40% efficiency — 40% of the BTU's in a gallon of ethanol powering an Alcohol Engine will produce mechanical energy that turns the wheels of the car.

Americans consume about 140 billion gallons of gasoline every year. If all spark ignition engines in the future were alcohol engines, then 140 billion gallons of ethanol per year would give American drivers a similar number of miles on the road as would 140 billion gallons of gasoline.

Ethanol has 1/3 less carbon per gallon than gasoline; so if 140 billion gallons of ethanol is burned in place of gasoline each year, delivering the same miles on the road, then cars and trucks with alcohol engines, fueled by ethanol, would emit 1/3 less carbon dioxide.

Today, at 140 billion gallons per year, gasoline engines emit about 1.4 billion tons of carbon dioxide every year. If all gasoline engines were replaced with alcohol engines, and all gas stations offered 100% denatured ethanol to fuel the engines, then only about 950 million tons of carbon dioxide would be emitted each year from 140 billion gallons of ethanol — a reduction of 450 million tons of carbon dioxide per year without reducing the number of miles driven or reducing the power and performance of the vehicles.

One hundred billion gallons of synthetic ethanol, plus 30 billion gallons of cellulosic ethanol plus 10 billion gallons of corn ethanol would equal 140 billion gallons. That is possible; what are we waiting for?