Some 250,000 people are being added to the world’s population every day. Of the more than 6 billion people now on earth, 3.7 billion suffer from some form of malnutrition. For these reasons and others now does not seem like a good time to embark on a program to turn a significant portion of the world’s food crops into fuel for automobiles. So says David Pimentel (pronounced: pim-men-TELL), the Cornell University agriculturalist whom many regard as the world’s leading authority on the energy content of biofuels and their effects on food and agriculture as a whole.

The growing drive for energy “independence” coupled with heavy subsidies has led to a scramble to build biodiesel and ethanol plants across the United States. “I wish that ethanol and biodiesel would save us,” Pimentel said at a conference entitled “Peak Oil and the Environment” held in Washington, D. C. recently. Unfortunately, green plants collect relatively little solar energy, he explained. Less that 0.1 percent of the sunlight that falls on plants gets converted into usable energy. That compares with about a 20 percent conversion of sunlight to energy by photovoltaic cells.

This means that biodiesel and ethanol production facilities end up being voracious though hidden guests at the world’s dinner tables. Humans get 99 percent of their food from the land and only 1 percent from the oceans, according to Pimentel. (This is in part due to the collapse of the world’s fisheries brought on by new forms of industrial fish harvesting and by high demand for seafood.) The more that we demand from the land in the way of fuel, the less that will be left over to eat, and the catch from the oceans is unlikely to make up for this loss.

Lester Brown, president of the Earth Policy Institute and author of the recent book Plan B, spoke at the same conference. He said that as long as oil remains above $60 per barrel, it will be profitable to produce fuel from crops. “The price for oil is becoming the floor for agricultural crops,” he explained. “We’re setting up a competition between service stations and supermarkets. The prices of agricultural commodities will be determined by their fuel value.” (my emphasis)

If oil prices remain high or even rise, they would continue to put upward pressure on grain prices. This could lead to political instability in countries such as Indonesia and Mexico which rely heavily on grain imports, Brown said.

But if, for the sake of argument, we didn’t concern ourselves with the effects of biofuels on food supplies, just how far could plant-based fuels go toward solving our looming liquid fuels problem? The U. S. Department of Energy now reports that currently less than 1 percent of all vehicle fuel consumed in the United States is plant-derived. According to Pimentel, even if we devoted all the corn raised in the country to making ethanol, we would be able to supply only about 7 percent of the country’s needs. Any claims that biofuels will make us energy independent just don’t hold up.

Even if biofuels could be produced in more substantial amounts, there is reason to believe they would not help us address energy shortages in the future. According to Pimentel’s work it takes 25,000 kilocalories of energy to produce one gallon of corn ethanol which contains 19,400 kilocalories of energy. That’s a loss of more than 22 percent (dividing the loss of 5,600 kilocalories by the 25,000 kilocalories of inputs). Other studies which claim to show an energy gain for ethanol leave out many inputs such as the energy used to create farm and processing machinery, the energy used to irrigate and the costs of the environmental impacts, he said.

(Pimentel’s critics argue that his methods underestimate the energy return on ethanol. He encourages them to submit their findings to refereed scientific journals where all of his research articles on the subject have appeared. So far none have done so.)

Many other biofuels perform even worse. Pimentel and his co-author Tad Patzek determined that it takes 45 percent more energy in the form of fossil fuels to turn switchgrass into liquid fuel than that liquid fuel returns in energy. The results for wood biomass, soybeans and sunflowers were 57 percent, 27 percent and 118 percent, respectively. In short, we are currently subsidizing the production of biofuels with fossil fuels such as coal and natural gas which provide the heat and electricity to process those biofuels.

So, given all of this, what is driving the biofuels market? The simple answer is money, said Pimentel. For instance, U. S. government subsidies mean that companies producing corn ethanol receive payments totaling $7 per bushel of corn processed. The corn farmers alas receive less than a 2-cent per bushel subsidy related to ethanol production.

Pimentel offers a simple test for whether ethanol producers really believe their own hype. If ethanol offers such a magnificent energy gain, then why don’t ethanol plants run on ethanol instead of coal and natural gas? Not surprisingly, this question has so far been met with dumbfounded silence.