by TreebeardsUncle » Thu 25 Jan 2007, 16:58:40
Here is an article that is at the bottom of the front section of the San Francisco Chronicle today:
"Energy experts knock ethanol as costly and inefficient source"
The article by David R. Baker starts off like this:
" Only one fuel - ethanol - can satisfy President Bush's plan to vastly expand America's use of gasoline substitutes, energy experts say.
And that might not be a good thing, they say.
In his State of the Union address Tuesday night, Bush said that within 10 years, he wants the United States to use five times as much alternative fuel as it does now. That step, coupled with tougher mileage standards on cars, would reduce gasoline usage by 20 percent, he said.
Ethanol is the only alternative fuel that can be produced in large enough qunatities to meet his mandate, many experts say. And, as it is made in the the United Sates, ethanol has serious drawbacks.
The vast majority of ethanol comes from corn. But diesel fuel powers the tractors that tends corn fields, natural gas runs the distilleries that produce ethanol, and more diesel is used to ship the finished product to market. The power you get out of corn ethanol, in other words, might just barely beat the power you put into it.
Scients have argued for years about how much of a net power gain corn ethanol provides, some insisting that it consumers more than it produces. The federal government, for its part, estimates that ethnaol gives about 1.6 units of energy for every unit that goes in. But even some researchers who agree say that the fuel doesn't provide much benefit in the end and that the nation shouldn't rely too heavily upon it to the detriment of other biofuels.
"That's really a step backward," said Daniel Kammen, an energy speicalist and co-director of the Berkely Institute of the Environment at UC Berkely. "We know that not all biofuels are created equal."
[Nor, does the article give a very positive endorsement of that pipe dream cellulosic ethanol.]
...
"This is still a technology that resides in laboratories and pilot projects," said Anthony Eggert , a research director with the UC Davis Institute of Transportation Studies.
...
[The article does give a bit more positive assessment for biodeisel though.]
The president specifically mentioned biodeisel as one alternative that could help wean America off oil. The fuel, which literally has been around as long as deisel engines, is twice as energy efficient as corn ethanol and can be made from a wide variety of natural, renewable sources, such as new and used vegetable oils and animal fats. But its use in the United States remains small, despite recent growth.
*****
So, what does the average barrel of oil have now in terms of EROI?
somewhere between 5 and 10
Would an EROI of 1.6 even "work." There isn't enough cropland in the US to run our current fleet on ethanol right, even if all the agricultural land was devoted to producing it? An EROI of 3.2 might be enough to run what, maybe half, of the current number of cars and trucks currently in use in the US?
Using trains instead of trucks for most freight transportation and requiring special licensing for suv drivers and pick up trucks to demonstrate real need to use the vehicles would help reduce excessive and unsustainable fuel consumption habits.