Ethanol's Promise, New York Times, Editorial, 5/1/2006

[Coastie for Truth]

The political scramble to find quick answers to rising oil prices has produced one useful result, which is to get people talking about substitute fuels that could make us less vulnerable to market forces, less dependent on volatile Persian Gulf oil producers and less culpable on global warming.

That, in turn, has focused attention on the fuel that seems to have the best chance of replacing gasoline — ethanol. President Bush mentioned ethanol in his State of the Union address. Entrepreneurs like Bill Gates have begun investing in it. And every blue-ribbon commission studying energy has embraced ethanol as a fuel of the future. One leading environmental group, the Natural Resources Defense Council, predicts that ethanol, combined with other strategies, could replace all of the gasoline Americans would otherwise use by mid-century.

Until recently, the only ethanol anyone had heard about was corn-based ethanol, a regional curiosity that accounts for about 3 percent of the nation's fuel and suffers from its association with the agribusiness lobby and with presidential candidates hustling support in the Iowa primaries. What the experts are talking about now, however, is cellulosic ethanol, derived from a range of crops, native grasses like switchgrass and even the waste components of farming and forestry — in short, anything rich in cellulose. A Canadian company called Iogen, a leader in the field, makes its ethanol from wheat straw.

Like corn ethanol, cellulosic ethanol can be used in automobiles, so it is appealing as an answer to oil dependency. And both forms of ethanol are inherently superior to gasoline in terms of reducing global warming emissions, since the carbon dioxide they absorb while growing helps offset the carbon dioxide they produce when burned in a car's engine. Cellulosic ethanol is in fact much more useful than corn ethanol on this score, because it requires far less energy to produce and thus emits fewer greenhouse gases.


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[papau]

1. Excellent editorial :-)

:-)

[Kagemusha]

2. Is it less harmful to engines?

Though granted, this has my attention because the energy to produce corn ethanol made the entire issue completely ridiculous and rightfully laughed at, as para #3 notes above.

[stopbush]

3. Ethanol's dirty little secret: it takes one gallon of gas/oil to produce

1.05 gallons of ethanol.

That's right. There's a 5% gain in the total amount of fuel yielded in the production
of ethanol.

I'm sure that number will improve over time, but that's where we are today.

[Coastie for Truth]

4. I would have to disagree

That is a number used by Shell oil, based on the Pimentel and Patzek (Ethanol Production Using Corn, Switchgrass and Wood; Biodiesel Production Using Soybean and Sunflower , but you have to pay $30.00 to download the PDF.

Reasonable people - even reasonable chemical engineers can disagree.

Pimentel et al. assume the most energy intensive route at every "design decision point" One can use "petroleum refinery engineering" paradigms of thermal cracking and catalyzed combustion of sugar, distillation, etc. (all of the things we learned in the petroleum refinery centric chemical engineer curricula of the 1950's) and get to even 1.5 gallons of gasoline from crude per 1.0 gallon of gasoline from, e.g., corn.

That's the wrong way to go. Take a look at the latest version of "Bioprocess Engineering: Basic Concepts" by Michael L. Shuler and Fikret Kargi (not that it's "the best" - just that it's the one I have). And forget about zeolites and think "Saccharomyces cerevisiae" (yeast). And forget about distillation and think about membranes processes (dialysis, phoresis, and microfiltration). Now you are thinking like a pharmaceutical manufacturer, or a vintner, or a food processor - but you capital costs and energy costs are MUCH LOWER - and the Pimentel-Patzek number are wrong.

Lesson - don't import petroleum refinery engineering into a biochemical process.

Coastie, PhD (Chemical engineering - from the good old days).

[stopbush]

5. You would know. but that 5% yield is the number being thrown

around right now by the oil companies. It either needs to be challenged or embarced...or both.

As I said in my OP, this seems to be a fact now - it could change down the road. If it is not a fact
now (today, as I type), then please enlighten me. The last thing I want to do is to go around
spoputing inaccurate info.

Thanx!

:)

[Coastie for Truth]

6. Word on "The Street"

Pimentel and Patzek are funded by Shell Oil.

Lavie (a personal friend; he said that hybrids burn more gas because the mileage is so good that hybrid owners drive many many more miles) - funded by GM.

I am not an ethanol guy per se. I started out in nuke power (what do you expect of somebody who was in engineering school in the 1950's?) and coal to gasoline. Got into solar and electrics/hybrids "after Three Mile Island."

I took a 4 credit course in bioengineering about the time I officially retired - played around in pathology lab diagnostic equipment, then into bio fuels. But in my college years I was a frat house braumeister, vintner, and moonshiner. (I was no competition for the Anheuser Busch family, or for the Gallo Brothers. or for Jim Beame)