Hey Dan, please throw the dog a bone and give us some cites of the
efficiency of ethanol?

Ethanol Production Using Corn, Switchgrass, and Wood;
Biodiesel Production Using Soybean and Sunflower
http://www.oregon.gov/ENERGY/RENEW/B...hanol.2005.pdf

The research includes 2001, 2003 and 2005. Is that current enough?

The Ethanol Forum
http://www.oregon.gov/ENERGY/RENEW/Biomass/forum.shtml

National Corn Grower's Association
http://www.ncga.com/ethanol/main/energy.htm
"Ethanol opponents frequently cite a study by Cornell University’s Dr.
David Pimentel, who concluded that it takes 70 percent more energy to
produce ethanol than it yields. Pimentel’s findings have been
consistently refuted by USDA and other scientists who say his
methodology uses obsolete data and is fundamentally unsound."

Amazing, the USDA thinks ethanol is wonderful. As Hillary might say,
this requires one to suspend disbelief...

Dave Hinz wrote:
On Sun, 16 Sep 2007 19:07:58 -0400, ATP* wrote:
"Dave Hinz" wrote in message
...

You'll be providn' a cite for that claim, right?

http://www.news.cornell.edu/stories/...ostly.ssl.html

Ahhh, Pimentel.

Interesting thing about Pimentel. In 1994, he co-authored a paper which
stated "Solar energy technologies, paired with energy conservation, have
the potential to meet a large portion of future US energy needs".
http://dieoff.org/page84.htm

Not sure that that's feasable. Later on, the paper says:

"Ethanol. A wide variety of starch and sugar crops, food processing
wastes, and woody materials (Lynd et al. 1991) have been evaluated as
raw materials for ethanol production. In the United States, corn appears
to be the most feasible biomass feedstock in terms of availability and
technology (Pimentel 1991)."

In this very paper, is the nugget of his that keeps getting thrown
around, 16 years later, as if it's current: "The total fossil energy
expended to produce 1 liter of ethanol from corn is 10,200 kcal, but
note that 1 liter of ethanol has an energy value of only 5130 kcal.
Thus, there is an energy imbalance causing a net energy loss.
Approximately 53% of the total cost (55¢ per liter) of producing ethanol
in a large, modern plant is for the corn raw material (Pimentel 1991)."

Yet, further in the paper, they write:
"The most promising systems rely on distillation to bring the ethanol
concentration up to 90%, and selective-membrane processes are used to
further raise the ethanol concentration to 99.5% (Maeda and Kai 1991).
The energy input for this upgrading is approximately 1280 kcal/liter. In
laboratory tests, the total input for producing a liter of ethanol can
potentially be reduced from 10,200 to 6200 kcal by using membranes, but
even then the energy balance remains negative."

So even Pimentel knows, for at least 13 years, that with 13 year old
technology, it took 6200 kcal of energy input to produce the 5130 kcal
worth of ethanol. So his very own figures show an 82.7 percent
efficiency, with 13 year old technology. Also, these figures ignore
possible cogeneration or other uses of "waste" heat, and of the material
left after the fermentation. Brewery byproducts used as cattle feed,
for instance.

Now, if we'd power the ethanol plants with nuclear-generated
electricity, then even the 17% net energy loss that existed 13 years
ago, is a lot more attractive than what we're doing now.