The Strange Energy Budget of Ethanol Production

joeflies writes "The San Francisco Chronicle published an article regarding research on how much fuel is required to make Ethanol. The results indicate that it make take 6 times more energy than the end product delivers."

Comments

comparisons?

[TheClam]

Compare this to gasoline and hydrogen and you've got yourself a real article.

Re:comparisons?

[kherr]

Minnesota Department of Agriculture has a comparison of energy costs to produce different types of fuel. Treat this as a starting point for information.

People seem to forget that we don't pump oil out of the ground and into our gas tanks, it requires some serious refining. I've also heard that ethanol processing essentially removes the sugars from the corn, leaving a high-protein slurry that can be used as animal feed. Since it's high in protein and low in carbohydrates it's a more efficient feed and causes lower emissions from the cows. Heh.

The real future is not in corn

[1967mustangman]

Ethanol has long been a problem. The real insteresting prospect is the company up in Canada that is creating ethanol from the woddy portions of plants with a genetically modified bacteria see this slash dot story http://science.slashdot.org/article.pl?sid=05/01/0 7/1846247&tid=14

This is flawed.

[EvilMagnus]

"Taking grain apart, fermenting it, distilling it and extruding it uses a lot of fossil energy," he said. "We are grasping at the solution that is by far the least efficient.".

He ignores the fact that, if we wanted to, we *could* arrange the production chain so that it was not dependent on fossil fuel. You could build your farming and fermentation facilities to use solar or hydro power, for example.

Sure, it's fossil-intensive *now*. But it's also not a major energy source yet. If we needed to we could clean up the energy chain - there's no part of the process that requires fossil fuel sources.

Re:This is flawed.

[WolfWithoutAClause]

Nah. The real point behind all this is that in USA they make ethanol from corn, because they grow a lot of corn, and powerful lobbies have introduced a huge subsidy to use that source of ethanol to try to keep the cheap biofuel from Brazil off the market.

Of course the Brazilian biofuel comes from sugar beat and so forth, which actually is somewhat efficient and gives a net energy win; which is why Brazil have been able to run lots of their cars on it for quite a while now.

So what this paper is really saying is not that biofuel is a waste of time, but that 'The American Government are morons' with their stupid corn-based ethanol subsidy. But you knew that already, unless you're a corn farmer.

In a nutshell

[Linux_ho]

The author is using data from thirty-year-old production techniques to shoot down the new "buzz" about tomorrow's efficient ethanol production. At the same time, he is ignoring the current research that is generating the buzz: researchers are just now coming up with efficient ways to produce enzymes that can turn raw agricultural waste into ethanol. That means stuff like sawdust, wood pulp, cardboard, corn stems, yard waste etc can be turned into ethanol instead of going into landfills.

Data about how much energy it takes to grow corn is irrelevant, because we won't be using corn. We'll be using lawn clippings, or pulverized construction waste, or re-re-recycled paper, or whatever.

Re:not particularly relevant...

[Mr.Sharpy]

sure, as long as there's oil, ethanol doesn't really look efficient or affordable except as a fuel oxygenator. but if the oil reserves were to run out sometime soon, ethanol could be poured into most of our existing infrastructure and ease the transition. that's why it's important -- not because it's inherently superior to petroleum, but because it can be manufactured (from scratch) much more quickly.

Did you even read the article? You're missing the entire point! If the oil reserves run out you won't be able to get any ethanol to pour in your car either! Corn based ethanol requires far more energy in its production than it is capable of producing itself, almost all of which comes from fossil fuels. In fact, according to this article producing one unit of energy in ethanol requires 2.3 units of energy to produce. That's gotta come from somewhere, and right now its going to be fossil fuels.

The bottom line is that ethanol programs are, right now, nothing more than another farm subsidy. The politics such programs are beyond the scope of this article, but suffice it to say that touting ethanol as the solution to our energy problems is at best disingenuous, dishonest, and a potentially disasterous diversion from the real technologies we are going to need to maintain our current life styles in the future.

Re:Hmm

[jcorno]

According to TFA, they are including the energy used in producing the fuel used for growing and harvesting the grain and for making the fertilizers. This should probably be backed out of the equation because these activities will take place anyway - regardless of whether or not we're using ethanol.

No, they won't. Farmers don't grow corn they don't intend to sell, and manufacturers don't make fertilizer they don't intend to sell. Both have increased production expressly for this purpose. Without the ethanol market, the farmers would cut back to keep prices under control. Same for the fertilizer.

Re:This doesn't pass the smell test

[linuxwrangler]

I smell politics.

Good nose. And when the politicians are bought and paid for by Archer Daniels Midland and friends the result is government subsidies for corn-derived ethanol and a full-court press to keep Brazilian ethanol (sugar derived) out of the US (just google brazil ethanol imports).

Checking Slashdot's Sources

[Passman]

I agree, this did smell funny. So I went out and did some research.

It seems that the "scientist" in this story, Tad Patzek (a geologist), has been working for the oil industry quite a bit over the last few years. Odd that he should suddenly be switching his interest to agriculture and begin attacking Ethanol.

Or perhaps it all makes sense if you look at it from the correct prospective.

Re:Hmm

[jericho4.0]

" How much petroleum goes into petroleum production?"

Good question. In the early days of oil production, it took one barrel of oil to get ~50. Oil was easy to pump (not very deep), and of high quality (pick and choose your oilfield). Nowadays, one barrel of oil gets you somewhere around 5, less in some fields. The big exceptions to this are a few, very large, oilfields in Iraq, Saudi Arabia, and the former Soviet states. Some might find some insight into recent US foreign policy here.

Return On Energy is being affected by several factors. Oil is now deeper and stickier, and takes lots of force to suck out of the ground. The gushers have gushed. It is also of lower quality, and more energy is required to refine it.

The ROE calculation for a particular oilfield is difficult to do. Oil producers are very secretive about some numbers, so the margin of error is significant. But what is clear is that the ROE is dropping, and will continue to drop. When it hits 1:1, oil becomes useless.

I think the most interesting thing about this, is that we won't know until after the fact. Suddenly the worker will not have enough paycheck to get gas to go to work in the factory that makes refinery bits, or some convulted economic chain like that. Another reason the calculation is so hard to do.

If we were having an oil deathpool, I would guess 15 years.

biodiesel and ethanol are compatable

[bluGill]

Don't forget that biodiesel and ethanol come from different parts of the corn plant. (Substitute your favorite plant) Ethanol is made from sugar/starch. Biodiesel is made from oil. You can extract the oil, without affecting how much sugar/starch is in the product. Then turn the sugar/starch to ethanol.

Don't only is this study heavily biased against ethanol by using outdated data, it ignores the biodiesel production (which is somewhat rare), and that the by products are useful in their own right.

Ethanol alone doesn't need to be energy positive (though it is - if you farm with modern methods), so long as you account for the energy left after producing ethanol.