Report: On-farm gains lead way for higher net energy balance with fuel

The energy gain of corn made from ethanol is growing, a new federal study says.

Ethanol made from corn produces as much as 2.8 units of energy for every one unit of energy used to make the fuel, according to a U.S. Department of Agriculture report.

In a 2004 USDA report, the net energy balance of corn ethanol was 1.8.

Increased efficiency by both corn farmers and ethanol producers has led to ethanol's greater energy balance, according to the new report.

"Ethanol has made the transition from an energy sink, to a moderate net energy gain in the 1990s, to a substantial gain in the present." And there are still prospects for improvement, says the report from USDA's Office of the Chief Economist.

The report measured all conventional fossil fuel energy used in the production of one gallon of corn ethanol. It analyzed the results of a survey of 18 dry mill ethanol plants in Minnesota, eastern South Dakota, Iowa and Nebraska, as well as federal data on total direct and indirect energy inputs in producing corn.

The net energy balance ranged from 1.4 to 2.8, the report says.

The 1.4 measures only the ratio of energy in ethanol to the external energy used to create it.

After allowing for the heat used to produce byproducts, the energy ratio is between 1.9 and 2.3.

Some ethanol plants already use biomass power. When that's factored in, the energy ratio rises to 2.8, the report says.

The 1.4 ratio is the best and truest measure, says Cole Gustafson, biofuels economist with the North Dakota State University Extension Service in Fargo.

What's causing the gains?

Much more energy is required to manufacture ethanol from corn than to produce the corn itself.

But most of the gain in net energy balance is coming at the farm level, the report finds.

Nitrogen use per bushel has declined by about 20 percent since the mid-1990s, according to the report.

"When farmers get better, so do we," says Ron Lamberty, vice president of the Sioux Falls, S.D.-based American Coalition for Ethanol.

Gustafson notes that many farmers have used less nitrogen in recent years because of high fertilizer prices. He wonders whether they'll use more nitrogen if fertilizer prices decline, which would reduce ethanol's energy balance.

Ethanol's energy balance also is growing because ethanol yields have increased about 10 percent in the past 20 years, which means proportionally less corn is need to produce one gallon of ethanol, the report says.

Keep in mind that the report isn't comprehensive. It measures results only at the 16 Midwestern plants, "which is marginally enough to discuss the results," the report says.

Controversial topic

There's a longstanding debate on whether ethanol produces more or less energy than is used to make it.

Though some disagree, the scientific consensus now is that ethanol has a net energy balance, Gustafson says.

The latest USDA report probably won't surprise people familiar with Midwestern agriculture and the ethanol industry, says Ron Lamberty, vice president of the American Coalition for Ethanol.

"We know it so well that we don't treat it (the report) with the fanfare we should," he says.

Many Americans still don't seem to realize that ethanol has a net energy balance, he says.

Ethanol should be more attractive than ever to the American public after the oil well disaster in the Gulf of Mexico, he says.

But that's not the case, he says.

"It's surprising we're not doing better," he says of public opinion regarding ethanol.

Some critics will try to discredit the latest USDA report by claiming the department isn't impartial, Lamberty says.

But objective, fair-minded studies consistently find that ethanol has a net energy balance, he says.

"I'm just so frustrated that we need to prove this over and over again," he says.