Anne likes Robert Zubrin's plan of making lots of ethanol from corn or sugar, and using that instead of oil to run our cars. Digging below the surface, the bottom line is that in 2008 we used 42% of our corn crop to reduce oil imports by 3.7%. So, we aren't going to replace a substantial amount of oil imports this way. But Anne didn't get into that aspect.
Anne's politics are certainly different than mine. She likes to talk about having little or no government, and letting the free market work. At the same time, the present crisis is so very bad, and OPEC is removing freedom from the oil market, so she says we need the government to fix it. Okay, so she's libertarian except when things are bad. A governing system that only works in good cases doesn't sound very robust to me, but that's not really the point of this blog post.
Another issue I have with her otherwise excellent presentation is that I don't follow how OPEC, which controls about half of the oil supply, can remove freedom from the market. You can read a detailed analysis at WTRG Economics which suggests that OPEC does not have even rough pricing control.
But I think this is just her ideology, and I don't care about that so much. What is more interesting is her presentation of Zubrin's plan (unattributed) for fixing our balance of trade / economic insecurity problem.
The basic idea in the Zubrin plan is to mandate that all cars sold in the US accept both alcohol and gasoline fuels. This change can be applied to all cars sold within a couple of years because it does not require large changes by auto manufacturers (contrast with hybrids, or plug-in hybrids, which have a much longer and more expensive adoption curve). Having made that change, within a few years a substantial number of consumers will be able to use high-alcohol-content fuels.. When alcohol is cheaper than gas, gas stations will offer alcohol, and so consumers will have an economic alternative to gasoline.
We can make alcohol from corn or coal, or we can import alcohol fuel. There are a lot of hazy details: corn-ethanol may be soaking up so much corn that we're starving people to death worldwide, corn may be crowding out the use of land for food, and it may be impossible to grow enough corn to matter.
The flex-fuel vehicle part sounds really good. There are a few other details which sound really good to me as well:
- Eliminate the tax on imported ethanol, so that it competes with imported oil (which has no tax).
- Eliminate the tax on imported sugar. Sugar cane is supposed to be a better feedstock for ethanol production than corn.
In the presentation above, one of the audience members asks if ethanol from corn replaces more oil than it consumes. Anne says yes, and it appears she is right. Here's a study of corn-ethanol production efficiency:
- Each BTU of corn-ethanol produced in the U.S. requires an average of 0.14 BTU of gasoline, diesel and fuel oil.
- This factor does not support the conclusion at the top of the study, that each gallon of ethanol displaces 7 gallons of imported oil.
- Correcting for the energy density of ethanol and gasoline, each gallon of ethanol produced domestically displaces 0.57 gallons of imported gasoline.
- The U.S. produced 13 billion gallons of ethanol in 2008, which displaced 7.36 billion gallons of gasoline, and reduced oil imports by 167 million barrels. We imported 4.39 billion barrels over the same period, so the oil imports reduction was 3.7%.
- The U.S. used 5.1 billion bushels of corn in 2008 to make that ethanol, which was 42% of the total of 12.3 billion bushels grown that year.
Bottom line: we aren't going to displace more than, say, 10% of our oil imports in the future by using corn ethanol. There just isn't enough corn.
The reason the question gets asked is that there is a different issue: does making corn ethanol yield more fuel energy than fossil fuel energy used? The answer here is: it's close. When you make ethanol, you make electricity along with it. When you add in the energy value of the coproducts, a little more energy comes out than fossil fuel energy went in (this energy was supplied by the sun).
So, the right way to think of ethanol production is as a coal-to-liquids system. It has the consequence of increasing the total amount of carbon dioxide emitted for a given amount of energy delivered to the automobile.
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