Why I Hate Ethanol

Each time I go grocery shopping I get more and more disgusted at the price of food increases. I know that there are many reasons why the price of food is going up: the devaluing of the dollar, food shortages throughout the world, increasing transportation costs, and so on. Many of these factors are outside of our control in the United States and some take a long time for the effects to be noticeable, but I believe that there is one area that can be quickly changed and where the effects will be readily noticeable…ethanol.

The following is a detailed partial reasoning behind my disdain for ethanol, if you aren’t interested in the details then feel free to skip to the conclusion at the bottom.

The United States is the largest single producer of corn in the world, producing 42% of the world’s supply during fiscal year 2006 (US Grains Council). For fiscal year 2006 81.8 million acres of land was planted with 75.1 million acres of land being harvested. The harvest yielded 11,114 million bushels of corn for a growth density of 136 bushels of corn per acre planted. After exports the domestic supply total was 9,136 million bushels. Of that amount 1,603 million bushels were used for ethanol. (USDA WASDE-457, April 9, 2008)

The estimates for fiscal year 2007 are similar but with a drop in total area planted/harvested to 78.3 and 70.6 million acres respectively. From that an estimated 10,535 million bushels of corn is expected, down slightly from the previous year. After exports the estimated domestic supply is expected to be 9,086 million bushel, again lower than 2006, but the amount used for ethanol is expected to increase to 2,117 million bushels. (USDA WASDE-457, April 9, 2008)

From the above numbers we can calculate that the percentage of corn grown that is used for ethanol is 14.4% for 2006 and 20.1% for 2007. The amount of our domestic supply that is used for ethanol is 17.5% for 2006 and 23.3% for 2007. Using the production numbers from fiscal year 2007 we can see that 8.4% of the world’s supply of corn is used up in producing ethanol for the United States, but how much ethanol do we get from all that corn?

The average ethanol yield from dry mill processing is 2.65 gallons per bushel, for wet mill processing the yield dips to 2.55 gallons per bushel (Argonne National Labs) (PDF warning). Using the yield estimates from fiscal year 2007 and assuming that all processing is done dry mill then we get an annual ethanol production of 5.61 billion gallons. This appears to be a large amount of fuel but let me put that amount into perspective.

Ethanol has the unfortunate characteristic of a low energy density. This means that for every gallon of ethanol you don’t get as much energy as you would get out of a gallon of gas and so your car can’t go as far. The following table (Wikipedia) will give an idea of how the energy density of ethanol compares. The units are MJ/L but the units aren’t important, the thing to notice is the difference between energy sources.

Nuclear Fission 1,5000,000,000
Gasoline 34.6
Body fat metabolism 35
Ethanol 24

Ethanol only contains about 70% of the energy per gallon that gasoline does. This means that if you had car that got 30 MPG with gasoline then on ethanol you would only be getting about 21 MPG. A result of this is that the 5.61 billion gallons of ethanol produced can only offset the consumption of 3.89 billion gallons of gasoline per year. That number still seems fairly large so let’s compare it to the average oil consumption in the United States.

Most oil consumption is measured in barrels but a simple conversion of 42 gallons per barrel will give us numbers that we can work with. The US petroleum consumption is currently at about 20,687,000 barrels/day (Energy Information Administration), this is equivalent to 869 million gallons per day or 317 billion gallons per year. All of this oil does not go to gasoline but almost half does. The US motor gasoline consumption is 388.6 million gallons per day (EIA) or 142 billion gallons per year. The ethanol produced from our corn is enough to offset 2.7% of our gasoline consumption and 1.2% of our annual oil consumption.

For ethanol to be economical it relies heavily on subsidies. In 2006 $7.0 billion was spent on corn ethanol subsidies. Of this amount, $5.4 was windfall profits for farmers. This money came from 3 sources

1. $0.51/gallon blenders credit = $2.5 billion (your tax dollars)
2. $0.9 billion in corn subsidies for ethanol corn (your tax dollars)
3. $3.6 billion extra paid at the pump

For all of this we are less than 1.2% more energy efficient and we reduced our greenhouse gas emissions by 1/19 of 1%. (zFacts.com)

Conclusion

Ethanol is dumb. It uses almost 10% of the worlds corn supply to offset our oil use by less than 1.2% and costs us billions of dollars. How much more good could we do if we provided the corn to the countries that are experiencing food shortages right now? How much more could we offset our oil use if we were to invest the money spent on ethanol into alternative energy research? It is good to be environmentally conscious but we should focus our efforts in activities that do more good than harm.