Burning Corn Directly versus Ethanol

 http://talk.newagtalk.com/forums/thread-view.asp?tid=56367&mid=395888#M395888

EDIT: adding the summary at the top here since some don't like to read long posts. Below, I'm providing numbers showing that we're wasting our ability to use corn for about 3x over, and I'd like to have an honest discussion on here about it. My parents and my grandparents didn't waste, so why are we doing it? It should be clear just how much dumb decisions like turning corn into a liquid fuel while we're burning other better liquid and gaseous fuels for stationary power and heat is really costing society. Any thoughts, guys? Obviously, I'm open to corrections on the numbers.

EDIT: Per Chris SE ILL's suggestion on an apples to apples issue, adjusting the bushel of shelled corn for burning by reducing the original amount 59,765. Since this is required to produce the bushel, the entire amount is deducted directly off the bottom-line net after burn number to make 305,088-59,765 = 245,323. This is the most aggressive way to reflect it, instead of subtracting it off of the gross amount.

http://energy.cas.psu.edu/energycontent.html

This is to get a discussion started on what's been posted in a few threads below.

Corn makes a very good thermal heat generator when burned directly. Based on what's in this story, about 6,810*56=381,360 net BTUs (after the loss for evaporating the moisture in the corn), and a corn stove can probably put about 80% of that (in terms of efficiency) into your home. Total value in terms of BTUs is 381,360*0.8 = 305,088 BTUs net per bushel of corn. After adjustment for production, as above, the net overall is 245,323.

Now, compare that to ethanol. Let's assume that we get about 2.8 gallons of ethanol per bushel of corn. Is that about right? You guys are the expert on that number not me. I would like to see the average for ethanol producers, not what the single best ethanol plant does on its best day.

Assume the net ratio is about 1.67 for the yield producing ethanol. The BTUs per gallon are about 76,100, so the net yield is 76,100*(1.67-1)/1.67 = 30,531. I saw a figure in a paper that the adjusted value to account for distiller's grains, etc, should be about 38,500, and that's higher than what I got, so we'll use that.

At the very best, if we burned the stuff in an 80% efficient furnace, we'd have net BTUs - accounting for the conversion to ethanol - of 38,500*0.8*2.8 = 86,240. 86,240/245,323 = 35.15% of the energy we'd have gotten in terms of thermal energy if we'd have just burned it directly.

And instead, we put it in a car and get about 20% of the potential BTUs as mechanical energy. Who had this dumb idea, and why are we trying to make more than just a minimal oxygenate out of it?

To top it off, you have the greenies over your head bitching about the amount of carbon you're introducting into the atmosphere from burning natural gas at the ethanol plant. If you burn the corn directly, it's neutral, and you should be immune from morons like al gore (though I'm sure he's going to try to get some money out of you somehow, anyway).

I'd like to see an objective discussion about why we're trying to make a motor fuel out of ethanol rather than burning the corn directly. It just doesn't make any sense to me. We put all of these heavy fuels through our furnaces when they should be going into vehicles on the road, and we should be burning the corn to heat our houses.

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