The Earth is finite so the supply of corn is finite. In a world with an ever-increasing population there is a very real danger of diminishing corn crops failing to satisfy the nutritional needs of billions of starving humans.

Of course, fat Americans seldom spend any time thinking about billions of people who suffer in this world.

Every few dozen years, someone says what you're saying. It was once Malthus. More recently, it was Paul Ehrlich. They were wrong then, they are wrong now.

Don't forget to point out the fact that if we were to run short of corn, the government could probably stop paying farmers to grow soy or leave their land fallow and let them make a profit on corn. As a city boy, I find it uncomfortably easy to be disgusted by American farm subsidies. Of course, I'm sure that some farmers out there are saying the same thing about money for museums, libraries, and education.

With any luck, biodiesel will help take care of some of the excess soy as well.

With all respect, I think it's fallacious to say that, in regard to the finiteness of resources, Erlich and Malthus were wrong. Criticisms are fair and expected, but failure suggests a proof.

Without taking up too much space here, an interior view of ethanol fuels from any source is that it's a weak and inefficient patch on an inherently flawed system of harnessing energy from combustion. Given that about 0.001% of a corn plant's biomass is fermentable (and that's a very generous estimate), and that fermentation yields of ethanol further account for only about 0.01% of that fraction(again with the healthy estimates), it only takes an extension to assert that 0.00001% of input (including arable land, carbon stores, fertilization products, etc.) is output as fuel. Add in combustion inefficiencies (about 70% lost in entropy) and we're down to three millionths of a percent net yield. That's just as bad as, or arguably worse than, fossil fuel combustion. It takes a lot of subsidies, not to mention additional space and resources for agrigulture, to make up for that deficit.

This is why ecologically-minded engineers argue that, since we have to invest heavily in new methods to store and release energy, it's only reasonable that we shoot for the highest efficicies possible in formats like solar capture and fuel cell technologies.

In the long run, we're all dead.

You're right that ethanol isn't a particularly efficient solution, nor is it one that will solve our energy problems for more than a few decades at most. Because cars are expensive, demand for motor fuel is highly inelastic (I actually did some research on just how inelastic at my old job; it's more inelastic than cigarettes).

But eventually, we're going to move on to something else, like hydrogen, which is why we should take advantage of more flexible supplies now. It'll never get out of hand because it's inefficient (like you said) and expensive.

There will never be a "peak corn?" Not so fast there rj3, I wouldn't be so sure of that.

If you're Amish and use manure for fertilizer and horses to do the field work you may be correct, but not if you're talking about the kind of industrial agriculture we have today that is entirely dependent on fossil fuels.

My grandparents ran a corn/dairy farm and used manure for fertilizer and he had a couple of big horses, and a small gasoline-powered tractor. His yields were 60-80 bushels per acre depending on weather.

Unfortunately, if all of today's corn farmers were running 60-80 bushel operations, there would not be enough corn to do all the things we want to use it for.

But in order to produce 150-160 bushel yields, corn farming has become utterly dependent on fossil fuels, and one can't even say corn ethanol is renewable.

At every step of the production process, "renewable" industrial corn farming consumes unrenewable fossil fuels:

1. Natural gas to make the nitrogen fertilizers corn farmers must have to grow high yields.

2. Diesel fuel for farmers to cultivate, plant, harvest, and transport their crop.

3. More diesel fuel to transport fertilizer, seed corn, and finished ethanol.

4. More natural gas on the farm to dry corn; more at the ethanol plant to mill and distill corn into ethanol; and still more to dry the waste distiller's grains after fermentation.

The hard fact is that growing corn is unsustainable without burning irreplaceable fossil fuels. Until corn farmers and ethanol plants show they can use ethanol instead of fossil fuels to grow grain and make ethanol, it is disingenuous to call corn-based ethanol a renewable fuel.

If corn-based ethanol ever became our primary liquid fuel, we would still be dependent on an overseas fossil fuel -- natural gas. The coming "oil and natural gas peaks" would also become a "corn peak."

Almost all ammonia fertilizer is now made from natural gas. What is not widely known is that an increasingly large percentage of that fertilizer is made overseas and must be imported into the U.S. I've even seen estimates that within five years we will be importing 100% of our nitrogen fertilizers, all made overseas from foreign natural gas.

Unless we are ready to become like the Amish or raise corn the way my grandfather did, corn production is unsustainable without fossil fuels. Unfortunately, if we go back to raising corn the old-fashioned way, we will also inevitable run into the "corn peak.

German farmers, like many other EU farmers, were producing too much grain. The German government, instead of just paying them not to grow grain or giving them price supports, has encouraged them to replace some of the excess wheat they were growing with rapeseed. It's a very oily seed that had been used primarily for cooking oil, but is increasingly turned into biodiesel, available at about 10% of German gas stations. Bavaria is covered with the little yellow flowers each spring. "The world's prettiest oilfields."

And best my eyes and unfortunate nose can tell, Bavarian farmers prefer cow manure. Maybe Germany's environmental laws are so strict that petrochemical fertilizers are heavily restricted and/or heavily taxed, or maybe it's a handy way to deal with all the cow poop from the dairy industry.

The German government also charges only the regular 16% sales tax on biodiesel sales, as opposed to the incredibly heavy taxes applied to petroleum-based fuels, making biodiesel about 10-15 cents a liter cheaper than petrodiesel.

If I stay here long enough to wear out the Volvo, I'll get a diesel.

I see you too are worried some about soil fertility shifting from feeding people to cars. I've followed Lester Brown and others on this issue.

That I have to offer is a redesigned city, town and village infrastructure that leaves out cars and de-emphasizes transit somewhat, while vigorously designing for bicycles and foot traffic: "access by proximity."

I write books on the subject you might be interested in and have a non-profit promoting the idea. You might like to check the book out: ECOCITIES - REBULIDING CITIES IN BALANCE WITH NATURE.

The web site is www.ecocitybuilders.org

If this ends up interesting you, great! Be in touch if you like.

Richard

PS: I was looking for the Zimbabwe connection with ethanol when I ran into your page here. It seems the Mugabe government is seizing farm land, plowing under vegetables and forcing farmers to plant corn - black farmers. You my remember he kicked out most of the white farmers over the last decade or so. The policy was said to be a move to help the country prosper, so I was wondering what the market was where corn - a low nutirition crop with a slim variety of nutrients - was being sold and am very suspicious it is for ethanol, and largely for export. I did learn for Lester Brown's research that ethanol comprises 15% to 20% of the Zimbawe gasoline fuel mix. Got any smoking gun on that?