# OT: The value of Ethanol

Totally OT but like Global Warming, Ethanol is a political hot bed.
I read today that the National Renewable Energy Laboratory states that "Today" 1 Btu of fossil energy consumed in producing and delivering corn ethanol results in 1.3 Btu of usable energy in your fuel tank.
David Pimentel a Cornell University professor estimates that it takes approximately 1.3 gal. of oil to produce a single gallon of ethanol. That's 1.3 gallons of oil for 1 gallon of ethanol. By comparison, simply refining a gallon of oil results in multiple gallons of gasoline. One year ago refineries in California were able to produce gasoline at about 98 cents per gallon when oil was \$75 per barrel. So today California is producing gasoline at a cost of about \$1.30 per gallon. Keep in mind "that cost" is not only the oil cost but also the cost to refine the oil. Assuming that \$1.30 is strictly the cost of the oil needed to produce a gallon of gasoline, a barrel of oil probably yields about 2.3 gallons of gasoline, again assuming that the cost to refine the oil is \$0.
I suspect that if we simply built more refineries we would consume less oil and the price of gasoline would go down.
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Somehow, that doesn't make any sense. Maybe a gallon of oil can REFINE multiple gallons of gas?

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Robatoy wrote:

Well, now we know that you know as much about chemistry as you do about Israel.

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--John
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A 42 gallon barrel of crude will yield approx 44 gallons of product. But it sure as fuck isn't all gasoline. 50% if it really sweet crude max! So, as usual, you're wrong, John.
BTW, have you ever been to Israel?
r
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A 42 gallon barrel of crude will yield approx 44 gallons of product. But it sure as fuck isn't all gasoline. 50% if it really sweet crude max!
Bummer! Here I thought there was some cold fusion as well as hot cracking going on to make one barrel of crude feed a multitude....
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To put it mildly

Toss a few loaves of bread and a few fish to that formula while we're at it?
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A 42 gallon barrel of crude will yield approx 44 gallons of product.
Where do the extra two gallons come from?
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It is a volumetric expansion. kinda like popcorn or a small block of sugar becoming a giant puff of candy-cotton. I sort of understand it that way. More compact molecules are altered to become larger. The weight does not increase AFAICT.
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Robatoy wrote:

... But "product" ain't all gasoline by any stretch...
Has some info, I'm sure the API and DOE sites as well as the other government labs and the oil companies themselves will have as much as you wish to delve into.
It will vary from essentially none to maybe as much as 65% depending on the source of the crude and the processing. Overall, I'd be surprised if it were much over 50% although I did no exhaustive searching.
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.
Most certainly not. I already stated elsewhere in this thread that a decent, sweet crude can yield 40% gasoline, through basic distillation and some other cracking methods. The rest is LPG's and even asphalt. Industrial fuels like Bunker C etc. and a whole lot more crap.
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No way Jose! If we could get politics out of energy I think we would be much better off (a dream, I know).
Why corn? Washington corn lobbyists?
Why not cellulose or grass? Too bad their is no money in yard clippings! Or maybe their will be, one day. http://www.sciam.com/article.cfm?id=grass-makes-better-ethanol-than-corn
Cellulose: http://www.harvestcleanenergy.org/enews/enews_0505/enews_0505_Cellulosic_Ethanol.htm
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Another ethanol from grass article I just dug up (published yesterday) from Chemical and Engineering News (a darn good rag!).
http://pubs.acs.org/cen/news/86/i02/8602news3.html
And no, smoking grass doesn't solve our energy problem.
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Theres a lot of good possibilities for this. If nothing else small plants could be built for individual cities. My city has free yard waste pickup. Think of all the free energy that could generate to run public services.
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Leon wrote:

Pimentel uses some very questionable assumptions in including a very low yield number on ethanol/bushel feed material that has been refuted in several studies. The last DOE study I saw was 1.6 iirc, but it includes some waste byproducts (dry distillers grains) used in that figure.

That would indeed be a neat trick, but I'm pretty sure even the oil companies haven't repealed the Second Law...
...

You might suspect that, but you would be wrong. Adding refinery capacity would help potentially, but that doesn't address why oil futures have touched \$100 -- making more refining capacity available will not do a thing to quell demand nor settle the political situation in the oil-rich regions of the world.
Granted ethanol is _not_ the panacea but can be beneficial in filling in supplies and will continue to be less costly w/ time as both genetics and processing technologies improve combined w/ sufficient infrastructure to handle it more efficiently than at present.
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What does this have to do with entropy? :^)
I think you meant the Law of Conservation of Mass.
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Still that is a poor ratio when compaired to oil.

Oil futures have reached \$100 per barrel because we have been deceived that gasoline has to sell for almost \$3.00 per gallon. When you sell gasoline for \$3.00 per gallon you are not so pickey with what you pay for the raw materials to produce that gasoline. Even those sellling the oil when it was \$70 per barrel indicated that that price was absurdly high. Building more refineries would increase the supply of gasoline and drive down the proice. There is no shortage of oil, only the ability to turn it into gasoline and I am not so sure that is true either. I have not seen any gasoline lines like we had in the 70's.
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Leon wrote:

Sorry, I mixed metaphors...I don't know the DOE number for the estimated oil consumption; while reading I was thinking of the Btu out/Btu in net energy gain that Pimentel has also been ranting on since forever...that is the 1.6 number the the DOE analysis produced. It's improved since the date of that report as well...
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dpb wrote:

Has to do with splitting heavy molecules into lighter ones, a process called "cracking" in the industry. A pound of CH3 takes up more volume than a pound of C2H6.

Does that mean that liquor's gonna get cheaper?
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I take it you mean CH4 (methane) and not CH3 (free radical).
But aren't we talking about liquids in this case right (GASOLINE)? Density of octane is 0.69 g/mL. Density of crude (varies from oil field to oil field) 0.85 g/mL.
1 pound of crude (metric conversion, Ugh! 1lb = 453.5 g) = 657 mL = 0.17 gallon 1 pound of octane = 533.5 mL = 0.14 gallon
If you could convert ALL crude to octane (and you can't, you lose some to volatiles) you would only get 0.03 gallons more.
(Considering ONLY straight chain hydrocarbons here) Larger hydrocarbons (than octane) would have smaller densities and the difference would be even less. Smaller hydrocarbons than octane (that are still a liquid at 25 oC) include pentane (d = 0.626 g/mL), hexane (d = 0.655), and finally heptane (d = 0.684 g/mL).
Considering the smallest hydrocarbon that is still a gas (pentane d = 0.626) gives 724 mL 1 pound of pentane yields 0.19 gallons for a difference of (from crude) 0.02 gallons.
So in order to make an 'marginal' increase in volume per unit weight, you would have to convert most of your crude into the lighter (and still liquid) hydrocarbons like pentane.

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Larger hydrocarbons (than octane) would have LARGER densities and the difference would be even less.
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