During the past several months, as lawmakers and energy experts have warned of a looming energy crisis, one alternative to gasoline that has been considered is ethanol, an alcohol fuel produced from corn.
But a new study by David Pimentel, a professor of ecology at Cornell University, threatens to nip some of the ethanol excitement in the kernel.
Pimentel's report, to be published in the 2001 edition of the Encyclopedia for Physical Sciences and Technology in September, says that producing ethanol is more trouble than it's worth: 131,000 British thermal units of energy are required to produce one gallon of ethanol, but a gallon will only give you about 77,000 Btu of fuel energy.
In other words, producing ethanol results in a net loss of energy.
Consequently, Pimentel thinks the only reason people like to talk about ethanol being a valid alternative to gasoline is "politics and large corporations who are getting big bucks from the government (in the form of ethanol subsidies)."
But ethanol advocates who were told of Pimentel's report on Monday were sharply critical of his findings. They called his conclusions "laughable" and said it contradicted all other studies they'd seen. One ethanol supporter also criticized Pimentel for issuing a press release months before the actual report – suggesting that Pimentel is more interested in the publicity that may come from this finding than in "good science."
This debate over the intelligence of getting fuel from corn is not at all new. At least since the late 1970s, when the fuel crisis prompted exploration into alternate sources of energy, some people have said that corn is the way to go, and others have said that corn advocates are dreaming if they think ethanol production is efficient.
Indeed, Pimentel's new study echoes his first report on ethanol, which was conducted when he was the chairman of the Gasahol Study Group, a Department of Energy task force convened by the Carter Administration in 1980.
Pimentel's studies are essentially just a big comparison of ethanol energy input versus energy output. He adds up the energy required for all the inputs in ethanol production – everything from fertilizer to pesticide to transportation costs to machinery – and compares them to the energy produced by ethanol fuels, called "gasahols."
"You add it all up and you find that you get a number that's 70 percent more than the energy you get from ethanol," he said. "And this is not new – this just brings the numbers up to date. We did the same thing back (in 1980), and back then they didn't believe us either."
After Pimentel's group released its study in 1980, E. Steven Potts, an aide to the Secretary of Energy, issued a memo to his boss calling the report an "attempt to railroad the gasahol issue," according to The Washington Post.
"I don't think anyone will pay attention to this report either," Pimentel said, "but we wanted to get it out (to the media) so you can see what's going on."
Trevor Guthmiller, the executive director of the American Coalition for Ethanol, was skeptical of Pimentel's report, specifically because he issued just a press release and not the full study.
"That tells you a little about their motives," he said. "I've had some ethanol producers who've called me and said that (Pimentel's) numbers are off-based. We have studies on our site, and they indicate that there's more energy in a gallon of ethanol than it takes to produce it."
One of these studies (PDF), conducted by U.S. Department of Agriculture scientists in 1995, concluded that there's a net gain of about 16,000 Btu per gallon of ethanol produced. The other, by David Lorenz and David Morris of the Institute for Local-Self Reliance, found that ethanol production can result in a 40 to 160 percent energy gain.
Since Pimentel hasn't yet released his full report, it's a bit unclear what accounts for the vast differences in these groups' conclusions. One possible reason, according to Phil Lampert, the director of the National Ethanol Vehicle Coalition, is that some people don't take into account the fact that ethanol is produced from a source that's available in abundance: corn.
"When we produce alcohol from corn, we're adding value to corn," he said. "About 10 billion bushels of corn were grown in the U.S. last year. Seven billion were fed to livestock and poultry and pigs. They need the minerals and the vitamins and the protein, and all we remove is the starch – and 100 percent of the protein, minerals and vitamins are still there. It's fed out to livestock poultry and swine."
He suggested that the ethanol critics are mistaken when they count the energy used in corn production with their figures for ethanol production, as Pimentel did.
Finally, ethanol advocates also criticized Pimentel's view that subsidies are the only thing that keeps ethanol in business. Guthmiller cited a General Accounting Office (PDF) report released last year. It found that since 1979 ethanol has received, at most, about $12 billion in government help.
Since 1968, though, petroleum fuels have received about $150 billion in subsidies, the report said.
"If they want to remove the subsidies given to the oil industry, the ethanol industry wouldn't need any incentives either," Guthmiller said. "We don't have soldiers in corn fields – but we have a heck of a lot of them in the Persian Gulf right now."
