Others have made this point, but it bears repeating. I wonder whether they did the same analysis for solar power, wind power, and hydrogen power. If they applied the same analysis, I suspect that they'd find that all three of these "sources" produced less energy than biofuels do.
The researchers included such factors as the energy used in producing the crop, costs that were not used in other studies that supported ethanol production, said Pimentel.
I also have to wonder whether they added some factor for the solar energy that allows all plants to grow. In reality, everything but nuclear power is a form of solar energy. The energy that we get from burning wood began as light energy that was converted to sugars in the leaves of a tree. Coal and oil are the same kind of energy except that the conversion process is longer. A researcher who really wanted to smear biofuels might add some factor to take account of the sun's energy used by the growing corn.
The study also omitted $3 billion in state and federal government subsidies that go toward ethanol production in the United States each year, payments that mask the true costs, Pimentel said.
This statement also casts doubt on the whole article. There's no term in a thermodynamics equation that includes a financial term. The financial cost of any part of the process has absolutely no bearing on whether the energy that comes from biofuels is greater than the energy required to produce biofuels.
Ethanol is an additive blended with gasoline to reduce auto emissions and increase gas' octane levels. Its use has grown rapidly since 2004, when the federal government banned the use of the additive MTBE to enhance the cleaner burning of fuel. About 3.6 billion gallons of ethanol were produced last year in the United States, according to the Renewable Fuels Association, an ethanol trade group.
The ethanol industry claims that using 8 billion gallons of ethanol a year will allow refiners to use 2 billion fewer barrels of oil. The oil industry disputes that, saying the ethanol mandate would have negligible impact on oil imports.
These paragraphs could be an example of conflicting statements where both are partially true and partially false. If the ethanol really increases octane, it could reduce consumption of crude oil by allowing more use of less valuable cuts of the crude oil. Refineries have to take steps to ensure that they can blend gasoline of the proper octane with the available feeds. If they just can't make the right stuff with what they have, they end up selling more by-products in other areas. Any addititive that allowed them to increase octane could help. On the other hand, the ethanol likely isn't as good as having the right blend of components in the crude oil.
Ethanol producers dispute Pimentel and Patzek's findings, saying the data is outdated and doesn't take into account profits that offset costs.
Now we have a skewed statement on the other side of the argument. The costs and profits are irrelevant to whether biofuels give more energy than is needed to produce them.
Another factor in the whole thing is whether the study looked at industrial-scale production or whether they looked only at bench-scale or pilot plant operations. Sometimes the energy required to produce a chemical in the lab is large in relation to the amount of chemical produced. However, when a production-scale plant is built and various heat inputs are balanced, the net energy may reverse.
Finally, if we can use nuclear power to produce biofuels for transportation, we may gain even if the biofuels require more energy to produce than they give. Hydrogen power will always require more energy to produce than it is capable of giving. That doesn't necessarily make it a bad transportation fuel. Biofuels may be the same way and should be considerably safer than hydrogen.
Bill
"There's no term in a thermodynamics equation that includes a financial term. "
Sure there is, it is a stand in for free energy costs which contain an entropy term. So you don't know what you are talking about.