The Price of Biofuels

[Ladywriter 7,783]

Making ethanol from corn is expensive. Better biofuels are years away from the gas tank. Farmers are reluctant to change their practices. But do we really have any alternative to biofuels?

It is not just the short-term economics of ethanol that concern agricultural experts. They also warn that corn-derived ethanol is not the "green fuel" its advocates have described. That's because making ethanol takes a lot of energy, both to grow the corn and, even more important, to run the fermentation facilities that turn the sugar gleaned from the corn kernels into the alcohol that's used as fuel. Exactly how much energy it takes has been the subject of intense academic debate in various journals during the last few years.

According to calculations done by Minnesota researchers, 54 percent of the total energy represented by a gallon of ethanol is offset by the energy required to process the fuel; another 24 percent is offset by the energy required to grow the corn. While about 25 percent more energy is squeezed out of the biofuel than is used to produce it, other fuels yield much bigger gains, says Stephen Polasky, a professor of ecological and environmental economics at Minnesota. Making etha*nol is "not a cheap process," he says. "From my perspective, the biggest problem [with corn ethanol] is just the straight-out economics and the costs. The energy input/output is not very good."

The high energy requirements of ethanol production mean that using ethanol as fuel isn't all that much better for the environment than using gasoline. One might think that burning the biofuel would release only the carbon dioxide that corn captures as it grows. But that simplified picture, which has often been conjured up to support the use of ethanol fuel, doesn't withstand closer scrutiny.

In fact, Polasky says, the fossil fuels needed to raise and harvest corn and produce ethanol are responsible for significant carbon emissions. Not only that, but the cultivation of corn also produces two other potent greenhouse gases: nitric oxide and methane. Polasky calculates that corn-derived ethanol is responsible for greenhouse-gas emissions about 15 to 20 percent below those associated with gasoline: "The bottom line is that you're getting a slight saving in terms of greenhouse-gas emissions, but not much."

If corn-derived ethanol has had little impact on energy markets and greenhouse-gas emissions, however, its production could have repercussions throughout the agricultural markets. Not only are corn prices up, but so are soybean prices, because farmers planted fewer soybeans to make room for corn.

http://www.technologyreview.com/Energy/19842/page1/

food should not be fuel

[Pchan 5,162]

I know of the Gober Gas project in India ... http://en.wikipedia.org/wiki/Gober_gas